If You Believe That Blankets Keep You Warm...

"My girl, my girl, don't you lie to me,

tell me where did you sleep last night?

In the pines, in the pines, where the Sun don't ever shine,

I'll shiver the whole night through." -Leadbelly, among many other variations

It's already been a couple of months since I wrote about Global Warming, and was deluged with comments that (to be kind) objected to the scientific consensus that the Earth is getting warmer, and humans are very likely the cause.

So let's just take a look at the basic physics of how a warm object -- like a planet -- stays as warm as it does in a cold environment, like interstellar space.

Image credit: NASA/Messenger/Johns Hopkins U./Carnegie Inst. of Washington.

And let's do this by comparing it with a much more familiar warm object in a cold environment: humans being outside when it's cold.

Taking a look at the picture below, you can easily imagine that, despite having a normal human body temperature, these people will get cold quickly, and if they don't do something about it, they run the risk of freezing to death.

Image credit: Spencer Tunick / AFP.

And this is simple thermodynamics: a warm object in a cold environment radiates its heat away until it decreases its temperature to match the outside environment.

If you don't want to freeze to death, and you can't change the outside temperature, you've really only got two options. Either you can add heat to the warm object, so even as you radiate your heat away into the outside, you can maintain a constant body temperature and not freeze to death.

Image credit: Origin unknown; retrieved from Running on Words.

For a human body, you typically do this by burning your stores of chemical energy at a rapid rate. But over longer periods of time, this is a highly dubious method of staying warm. You are much better off taking the simplest route: trying to maintain the heat you already have!

Image credit: Kerry Milligan and David Preston's Travel Blog.

And you know how to do this: you wear clothes and wrap yourself in blankets! Your body is still going to radiate heat away into the outside, cold environment, but the blanket does two very important things to make it harder for that heat to leave you:

  1. The blanket is going to absorb the heat your body is radiating. By heating up to some intermediate temperature and being in the way of your radiation, it inhibits the rate of heat flow from your body to the outside environment, meaning you lose heat more slowly than you would otherwise. And...
  2. The blanket is partially reflective, meaning that some of the heat emitted from your body either gets reflected outright from the blanket back towards you or absorbed and re-emitted from the blanket back towards you.

Image credit: Post & Beam.

As anyone who's ever been underneath too many blankets can tell you, this can even make you too hot very quickly!

Now, for systems like blankets and insulated houses, you need to think about more than just radiation; you need to consider conduction and convection to get the details of heat flow right. But for a planet, this simple picture tells most of the story.

Image credit: Hive Studios and National Geographic.

Planets generate some of their own heat from radioactive materials in their interior, they receive the rest of their heat from the Sun, and they radiate that heat back into the cold depths of space.

And this simple model works incredibly well for predicting the temperatures on planets like Mercury and our own Moon.

Image credit: MESSENGER, NASA, JHU APL, CIW.

On Mercury, for example, the side facing the Sun gets very hot, as it absorbs the Sun's radiation and is extremely close to the Sun. The hottest daytime temperatures on the planet Mercury get up to a blistering 800 °F (427 °C), hot enough to boil the element mercury; hot enough to melt tin and lead.

But during the long nights, Mercury radiates its heat away, achieving lows of -270°F (-168°C), giving it the largest natural temperature swing of any known place in the Universe (so far).

But Mercury, the Moon, and other similar bodies in our Solar System behave in this simple, easily predictable manner because they have no atmosphere on them. Not every planet is like this, however.

Video credit: European Space Agency.

Because most planets have a blanket in the form of an atmosphere wrapped around them, as exemplified by Venus, above. Venus is perhaps the most extreme example of what happens if you wrap a thick blanket around a planet: the maximum temperature on Venus is 460 °C (860 °F), and despite taking more than 200 days to spin around once, Venus' temperature is the same whether it's day or night!

This is despite Venus seeing the Sun as only being one-quarter as bright as someone on Mercury does, and yet Venus is always hotter than Mercury, even comparing Venusian midnight with the hottest part of the Mercurian day! This atmospheric blanket -- made out of 96.5% carbon dioxide -- is what keeps Venus in its inferno-like state.

Image credit: NASA / International Space Station.

Now, knowing what happens on Mercury or Venus is nice, but it's time to ask the question of what's happening on the Earth. We definitely have an atmosphere, but it's very different from the one on Venus. (Thankfully!)

Our atmosphere is nearly all nitrogen and oxygen gases, which are practically transparent to both the light emitted by the Sun and the heat radiated by the Earth. But after nitrogen and oxygen, the next most common elements in our atmosphere are water vapor, argon, and carbon dioxide. While argon is also practically transparent to visible light and the Earth's thermal heat, both water vapor and carbon dioxide -- just as it does on Venus -- behave as a blanket on Earth, as you can see from their absorption spectra.

Image credit: T. Everth, retrieved from S. Deichman.

So a fair and accurate picture of our atmosphere is to treat it as a thin blanket, not nearly as effective (and oppressive) as Venus' atmosphere, but definitely as having a non-negligible impact on our temperature.

Well, what has been the effect of humans on the thickness of this blanket? While water vapor self-regulates its atmospheric density based on factors such as temperature, carbon dioxide does not. In fact, if we look at carbon dioxide density in our atmosphere, recently, and compare it with our carbon dioxide emissions since the start of the industrial revolution, here's what we find.

Image credit: Oak Ridge National Laboratory.

Without a doubt, we have increased the thickness of our blanket, albeit just by a little bit. Now, we can argue about, quantitatively, just how much of an impact this thicker blanket has on our temperature. Some argue that it's quite large, some argue that it's small enough that it doesn't matter, and while the models generally agree that a thicker CO2 blanket makes the Earth warmer, there isn't a consensus as to "how much." (See here for a roundup of the latest.)

But as far as the thickness of our blanket goes, we can see that it's increasing, and that more recently, it's increasing at an accelerating rate.

Wouldn't it make sense to look at the measured average temperature of the Earth during this time? Our reliable temperature records go back to about 1880, when widespread data from thermometers is first available. Let's take a look and see what we find.

Image credit: NASA GISS, retrieved from skepticalscience.com.

Now, I am fully aware that showing a correlation between the carbon dioxide levels in our atmosphere -- of which the rise is indisputably caused by man -- and the global average temperature doesn't necessarily mean that one caused the other.

But given what we know about carbon dioxide absorbing heat, given what CO2 atmospheres on other planets do, and given the disastrous effects that continued rising temperatures are having (to say nothing of the scientific consensus on the issue), don't you think -- at the very least -- it's time to stop putting on more blankets?

Image credit: Magda Wojtyra.

If you believe that blankets keep you warm, then it's inconsistent of you to believe that emitting carbon dioxide into the atmosphere cannot possibly cause a rise in the Earth's temperature. And if you still don't believe it, then I politely invite you to go to Venus.

(My kudos to Alex for his eloquent inspiration for this post.)

More like this

Great post Ethan. I will share this with my climate change denying friends who think because it still snows, the Earth cannot be warming. Thanks!!!

Cue the denialists in 7 posts (my best estimate)...

Heh. From that first graph, it's obvious how to open a new window...we need to get rid of all that horrible oxygen in the atmosphere!

(But it does make me wonder how much influence the oxygen catastrophe had on early climate.)

Nice article Ethan. I hope that these types of discussions will get the idea across to people who can't/won't understand the finer points of the science or the statistics.
And, kudos for the Leadbelly reference.

(I know this won't appeal to the "deny at all cost" group, so get prepared for incoherent rants from the likes of Neil Craig about how you're wrong and believe it because you're on the big-government conspiracy.)

Very interesting post. I think it would be useful to extend the metaphor a little bit - the nitrogen and oxygen as the skimpy negligee, it sure makes the Earth attractive, but it's not going to keep it warm. And in comparison, the blanket of water vapor and the blanket of CO2, with their comparative insulating effects, and how much thicker the blanket is now than pre-industrial revolution. One of the favorite arguments is, CO2 is such a small percentage of the atmosphere that doubling or tripling it can't have a significant effect. So - how much of the blanket is it?

Totally not the point, but sunspots have a significantly larger temperature swing (a "cold" spot at about 3000 K relative to the surface temperature on the sun of 5800 K is a swing of 2800 K, versus Mercury's 600 K).

By Tom Singer (not verified) on 30 Aug 2011 #permalink

The blanket analogy is used often, but of no use. The CO2 blanket doesn't cover the sun. It all comes down to the fact that it's very different whether you cover a source that is actually generating heat or just prevent a warm object from cooling using insulation. In the second case you will never ever get a temperature increase.

Yeah, the Leadbelly reference sucked me in.
I have the Mark Lanegan version - many thanks for the Wikipedia link, too: apparently Kurt Cobain played guitar for Mark Lanegan's recording of it - something I haven't known in 20 years of owning the CD. Maybe I should read liner notes.

As for explaining CO2's effects on climate change - it's a very neat exposition, but the Deniers seem unconvincable.

By Vince whirlwind (not verified) on 30 Aug 2011 #permalink

Hans,

But Venus still gets heat, both from its core and from the Sun, it's just lousy at radiating it away.

I'm a little curious as to how you would explain why Venus is the hottest planet in the Solar System, if you think this explanation is flawed?

Hans, on cue, is the first idiot to turn up.

The heat source is the Earth. The Earth is warm/space is cold. The Earth radiates heat into space. The blanket keeps us warm.

Meanwhile, the Sun continues to add energy to the earth. The blanket doesn't prevent the Sun's energy from reaching the Earth. The amount of energy reaching the Earth from the Sun remains relatively constant over time. The amount of energy leaving the earth reduces as the blanket gets thicker.

I'm fairly sure my 8-year-old has been able to grasp this simple concept for at least the last 3 years. What's *your* problem Hans?

By Vince whirlwind (not verified) on 30 Aug 2011 #permalink

@Vince - Oh don't be too harsh on Hans. We're really only the sum of our experiences aren't we? Just because Hans has been taught the wrong thing doesn't necessarily make it his fault. Always remember that it is easier to prejudice someone than it is to educate them.

Although I must admit I was having dinner last night and overheard somebody say "choosed" (instead of "chose") and I believe such an error to be completely unforgivable.

PeterC:
The two biggest errors of that type I hate for my stat students to make:

"loose" instead of "lose"
Using an apostrophe to say (essentially) "Look out, here comes an s" instead of its proper use

Sorry for the off-topic comment Ethan.

Well, the challenge is on: will Hans admit to his mistake?

By Vince whirlwind (not verified) on 30 Aug 2011 #permalink

Hans can't see the obvious point that visible light passes clear through our atmosphere (the blanket) and strikes the dark surface of the earth, where the light is converted to heat. The blanket is then opaque to that generated heat. (This is why people are nervous about the reflective polar ice melting into light-absorbing sea water.)

Also, we know that the CO2 is not natural by noting the changing ratio of 14C/13C in the CO2. The isotope ratio of CO2 emitted from life and other natural sources is different from that of burned fossil fuels. We can see the ratio over time approaching that of fossil CO2, telling us that CO2 from fossil fuels is definitely the source of the increased CO2.

By S. Williams (not verified) on 30 Aug 2011 #permalink

I'm not sure Hans was objecting to the idea of warming; it seems to me he was objecting to the analogy instead.

However, the analogy does hold up. Most blankets are not impervious to external heat, which is why it does actually make sense, on a chilly day, to sit in front of the fireplace (or space heater) while wrapped in a blanket. The blanket does slow the heat considerably, but it doesn't stop it. Instead, what it does is it moderates the heat. You don't wind up with a hot front and a frozen butt. Sort of like Mercury, actually -- take off the blanket, and it's less pleasant. Put a blanket on, and you stay warm, but not too warm. Put another one on, and eventually you'll get too warm.

By Calli Arcale (not verified) on 30 Aug 2011 #permalink

Hans,

Car. Hot summer day.

If the blanket analogy is satisfying I get stuck with other problems.
We get radiation from the sun resulting in a temperature Ts at our surface (aprox. Stefan-Boltzmann). If there were no atmosphere it would be as cold as space above the surface. An atmospheric layer captures part of the energy and thus gets a temperature Ta. Thermodynamics for radiation between two layers says Ta can get as high as Ts, higher is not possible. So no 'blanket' above earth can get the surface to rise in temperature, we do get Ts for the whole atmosphere.

Hans,

You are doing the calculation for an object without an atmosphere and getting Ts.

You are postulating that an atmosphere will be at a temperature Ta that is in between Ts and 0, and then stating that the thing at Ta cannot make Ts hotter.

And that is why you need to understand the blanket analogy. It isn't about the difference in temperature between the layers (which confuses almost everyone who isn't a professional physicist, and some who are), it's about heat. If you can understand the heat, the temperature comes easily.

The Sun emits heat, the Earth holds it for a time, and then re-emits it into space. The total amount of heat on Earth at any given time determines its average temperature.

With me?

This is the calculation you did for Earth to arrive at your original Ts. The calculation is done here on wikipedia, where they arrive at a temperature for Earth of about -20 Celsius.

Now, this is for a planet without an atmosphere. Add an atmosphere in, and what happens? It holds the heat in for longer. That means more total heat on Earth at any given time, because it's got the Sun's heat that it had in your Ts calculation, plus a few percent of the heat from an earlier time, plus an even smaller percent of the heat from an even earlier time, etc. Hence, the temperature now is hotter than your calculation gave for Ts.

It's very straightforward to calculate Ts for Venus, the Earth, etc. And you can go outside and actually measure the temperature, and find that it's much hotter than that. That's the "blanket" effect I'm talking about, commonly known as the greenhouse effect, but it works more like an actual blanket than a greenhouse.

(And for those of you keeping score and counting links at home, yes, my own comment #16 got caught in my spam filter.)

Dean@10:

Surely that should be "look out, here come's an s"?

;)

Tangentially

First the global warming denialists, taught by the wonderful ExxonMobile funded denialists who were, cough, scientists, railed that global warming was a fraud.
Then...
When the evidence was too much for reasonable people to deny that global warming was happening...
One moment please while the goal posts are moved... there.
People didn't do it, the earth is heating naturally.
If you're still denying global warming, does that mean you didn't get the memo? The goal posts have been moved, people.

By Bill Minuke (not verified) on 30 Aug 2011 #permalink

Thanks for that simple and clear explanation. Yes, it is incredible that people deny such obvious logic. The question in my mind though, is what are the emotive forces that drive people to deny climate change? We know that the energy industry/lobbyists are feeding the denialist camp and that their compliant politicians exploit it.

But why has that denialist message resonated with the general population?
Could it simply be the fact that the average person cannot yet feel the change because it is buried in daily/yearly climate variation? That, unable to directly detect the change, it seems to contradict his 'commonsense' interpretation of the world? Add to that the fact that daily we examine the weather to make decisions about things like what clothes to wear. That makes each of us instant climate 'experts', more ready to trust our 'commonsense' interpretation over the undetectable (to the individual) predictions of the climate scientists. Then add to that the fact that weather forecasting has been for a very long time a rather imprecise science. This has conditioned us into believing that climate scientists are simply not that good at their jobs.

While the science is absolutely clear and indisputable, its message is being rejected. Blame will not solve the problem. It is only by understanding the source of the rejection that we can tailor the message to overcome the objections.

I have a completely different point about global warming, one that I think is too often skipped when discussing it. I'm a firm believer in global warming, I completely agree with everything in this post.

Imagine if cold fusion was invented. Free energy for all, in copious amounts. Imagine the transformative power this would have on the entire world's economy. I think it is fair to say, it would just change, absolutely everything. Try to imagine its effects on many parts of life, such as heating, transportation, electricity. In economic terms, this would eventually touch every part of life, as everything depends in the end on energy. It would be a revolution.

Here's my point - this has already happened! Exactly this revolution happened when fossil fuels were discovered. Today fossil fuels make up about 90% of human's energy consumption, and this is no accident. They offer huge amount of energy, very cheaply, and our entire new world has been built around them. I personally think, the reason the human condition has improved greatly in the last few centuries (right down to life expectancy), is not mainly because of advancements in science and technology, but mainly thanks to the discovery of fossil fuels, from where most other things follow.

My point here is, when people say we should stop using fossil fuels, in order to save the environment (a worthy goal!), they need to realize the scale of their request. Fossil fuels are the foundation of our entire modern society. Alternative energy, to put it mildly, is hard to accomplish. Again, it is worth it! But the scales are immense, and it is important to realize this. And we might need to accept, that alternative energy will never give the same cheapness to energy that fossil fuels gave. Which means, switching to them, would almost certainly have a negative effect on our economy and, eventually, humans' well being.

(I HIGHLY recommend the book "Without the Hot Air", freely downloadable, a no-nonsense physics numbers book discussing alternative energies)

(P.S. I actually understand why this discussion is frequently ignored, because we can't seem to get everyone past step ONE, which is realizing that there is a problem at all.)

I do have to accuse the American media for their part in the public's misunderstanding of problem of GW. In the medias general presentation of GW it is not taken seriously, is often openly ridiculed or when presented in a "balanced" story, it's often balanced by comparing a scientists statement with that of an unqualified denialist ( or worse a man on the street.) Given that most Americans aren't scientifically minded (present company excepted), I believe they adopt the view they hear most often.
Moreover, most people are swayed by anecdote rather than good science, so they'll generally believe a compelling story over the facts.
Additionally, since this has become such a political issue it quite overshadows the science, there is a lot of dogma in this fight now, facts and truth just stand in the way of dogma ( i.e. Climate Gate, a PR coup for denialists, even though every scientist involved was exonerated). To them I say, get your politics out of my science!

I do have to bite my tongue, for fairness sake, and support the role of the skeptic, but only when their facts and science are correct. Honest criticism is good for science. My opinion of the current situation is that it's been poisoned against the honest GW skeptic.

By Bill Minuke (not verified) on 30 Aug 2011 #permalink

And that is why you need to understand the blanket analogy.

So when someone says an atmosphere cooler than the surface must make the surface cooler, the response is: since a blanket is actually cooler than your body overall, you must believe the blanket makes you cooler than without it.

By Chris O'Neill (not verified) on 30 Aug 2011 #permalink

TO #21

From your post I gather you're in favor of continuing on the current course of burning fossil fuel; actually oil, I hope you're not advocating coal. The problem is we don't know if GW will be so destructive at some point ( i.e. scenarios: US breadbasket becomes a desert, hurricanes wipe out major cities) that it offsets the benefits of fossil fuels economically or worse GW plays out as a doomsday where it's just too hot to survive.

The other problem is that we're not really going to suffer from GW, we're passing that batton to our kids and their kids. Let them figure it out, that's not nice :)

Moreover, though and this is a biggy, the US consumes about 25% of the energy consumption of the world, but we have less than 5% of the population, what happens when India and China, start to consume at the levels that we do; let's not forget that they may not have the environment regulations that we have. They could argue that cleaning up their fuel would be an economic burden.

Also, oil will not last forever. Before we run out, should we be transitioning to a variety of renewable resources rather than dragging our feet until it's mostly all gone?

I think we can conserve energy and maintain a high standard of living and a powerful economy.

I'm not going to argue that gasoline isn't gold. Wind, waves, and sunlight are minor players. Coal is worse than oil; "Clean Coal" is just like safe poison, an oxymoron. I like nuclear, it's not polluting and less radioactive to the environment than coal, but it's politically untenable. But rather than say all of the alternatives are poor so let's stick with oil, I say, let's make a "Manhattan Project" level commitment to developing the next big clean energy.

I would like to see some numbers. If you give an economic argument, how much will we lose by using less fossil fuel or developing alternate sources?
On the flip side how much arable land will become desert, how much sea level land will disappear and a what time scale if GW happens at current levels.
More generally, what are the most likely pro's and con's of staying on our current path, alternately what are the best options for combating GW while still maintaining our standard of living.
#21 I'm not picking on you, I think these are valid questions and worth asking. Even if we didn't do anything about GW we should ask these questions.

By Bill Minuke (not verified) on 30 Aug 2011 #permalink

Look, it's an analogy. The usual point of an analogy is that it's comparable to a part of a larger, more complex thing, but it helps spread understanding of the more complex thing. If it weren't simpler, then you might as well just explain the more complex in detail. But, being a simplification of just a part, it doesn't catch every nuance.

So yeah, we don't usually have blankets that allow heat to flow one way more readily than the other. Hence, the analogy is imperfect. BFD.

By Randy Owens (not verified) on 30 Aug 2011 #permalink

"The blanket analogy is used often, but of no use. The CO2 blanket doesn't cover the sun."

Indeed not. It covers the earth.

An earth that is in a colder universe, just as our pale pink bodies are in a colder atmosphere.

If we blanketed the sun, we would not be able to get as much heat from the sun and we'd COOL.

"Thermodynamics for radiation between two layers says Ta can get as high as Ts, higher is not possible."

This is the inerrant screed of all denialists.

Hans, thermodynamics for radiation says that the NET radiation transfer between a hot and a cold body must be in the direction of decreasing temperature.

HOWEVER, this DOES NOT mean that a cooler body doesn't radiate.

Any body above absolute zero radiates energy.

And that cooler atmosphere will radiate to the warmer earth.

What happens when you increase the thermal energy input into a body, Hans?

See

http://scienceblogs.com/startswithabang/2011/07/what_the_wmap_image_mea…

For another deluded denialist unwilling to accept the incorrect results because they make them feel better.

"The question in my mind though, is what are the emotive forces that drive people to deny climate change?"

Avoiding blame.

For most.

Other major reasons include:

Religion (God Promised: NO MORE FLOODS).

Religion (God Wouldn't Do That To His Chosen (tm))

Religion (This Is The Rapture!)

Greed (My Job Depends On It)

Greed (My Pension Depends On It)

Hate (Green Enviro Nazi Communist Maoist Atheists!!!!! With Liberal Amounts Of Spittle)

Politics (Democrats Are For It? I'm Against It!)

Arrogance (How DARE You Tell Me What To Do!!!! More Spittle Please)

Fear (DO NOT WANT!!!)

But the biggest single one is the desire to be blameless. It's ALWAYS someone else's fault.

"Today fossil fuels make up about 90% of human's energy consumption, and this is no accident. They offer huge amount of energy, very cheaply"

As long as you don't clean up.

Tell me, how much is your life, and the life of your extended family, worth?

How cheap is life to you?

"the reason the human condition has improved greatly in the last few centuries (right down to life expectancy)"

See, for example, "Smog" in Wikipedia. See also the reducing life expectancy in the USA.

The change isn't oil, it's science, and for life sciences here in particular.

"Fossil fuels are the foundation of our entire modern society."

Indeed: just like slavery was the foundation of the Feudal Society. And Fossil fuels, like slavery, will be the downfall of our society. See, for example, the Greeks: killed by their slaver economy.

"Alternative energy, to put it mildly, is hard to accomplish."

Really? Please explain how, since there are many plans, and workable ones, to have a 100% renewable future. To supply 100% of the planet's energy needs you need solar panels 230km on a side. That's all.

In what way is this hard to accomplish?

"And we might need to accept, that alternative energy will never give the same cheapness to energy that fossil fuels gave."

See above, re: cleaning up. Onshore wind power is now cost comparative with coal (which is cheaper in power stations than oil).

Maybe you have to accept that alternative energy is cheaper. Maybe you need to accept that fossil fuels will run out.

"Which means, switching to them, would almost certainly have a negative effect on our economy"

See above.

"and, eventually, humans' well being."

See, again, about smog, etc.

Also look at Fukishama.

"I HIGHLY recommend the book "Without the Hot Air", freely downloadable, a no-nonsense physics numbers book discussing alternative energies"

Someone else recommended it. They didn't know that the maths were fiddled to make renewables impossible, since the writer wants nuclear power to be the next big thing.

His paper is a hatchet job, asserting that it is not what it in actual fact is: a load of hot air.

Bill: I would like to see some numbers. If you give an economic argument, how much will we lose by using less fossil fuel or developing alternate sources?

Look up the Stern Report.

@14 Stu

Airco! Problem solved.

The Pontifical Academy of Sciences (of the Roman Catholic Church) issued this statement:

We call on all people and nations to recognise the serious and potentially irreversible impacts of global warming caused by the anthropogenic emissions of greenhouse gases and other pollutants, and by changes in forests, wetlands, grasslands, and other land uses. We appeal to all nations to develop and implement, without delay, effective and fair policies to reduce the causes and impacts of climate change on communities and ecosystems, including mountain glaciers and their watersheds, aware that we all live in the same home. By acting now, in the spirit of common but differentiated responsibility, we accept our duty to one another and to the stewardship of a planet blessed with the gift of life. We are committed to ensuring that all inhabitants of this planet receive their daily bread, fresh air to breathe and clean water to drink as we are aware that, if we want justice and peace, we must protect the habitat that sustains us.

See also this statement to the May 11 2006 session of the U.N. Economic and Social Councilâs Commission on Sustainable Development

NASA should get a much bigger budget. It´s them who solved the CO problem aboard the Apollo-13 with non-matching parts and ducttape.
If someone can solve this it´s them!.

By Pragmatist (not verified) on 31 Aug 2011 #permalink

"The Pontifical Academy of Sciences (of the Roman Catholic Church) issued this statement:"

I didn't say that the institutions of religion is the cause of denial.

You asked what makes the people themselves deny AGW.

The reason for a large number of them is Religion.

Many christians disbelieve evolution, despite the RCC's statements that it is a factual description of reality. This is their religion. Unless you've canvassed a lot of christians and found a different answer.

Note also that Catholocism is one of several hundred different sects of christianity, never mind counting sects of religion as a whole.

To Bill, #24

Looks like you're mixing several different issues together in a confusing way. If we're talking about Global Warming, then CO2 emissions are the only issue, and all fossil fuels are identical. Differences in types of coal, oil, and natural gas are about particulate emissions (smog) and oxides of sulfur and nitrogen (acid rain). Not to say these aren't potentially issues, but don't get them confused with global warming.

Manhattan project... I see these types of ideas a lot from people who aren't engineers. You guys need to understand that you can't just throw money at any problem and make it go away. The Manhattan project and Apollo and other big-government projects were appropriate because the basic theory to make the end result happen was already known, and all that remained was to work out the engineering details. As far as replacing fossil fuels to a high enough degree and speed to affect Global Warming, there is no basic theory and no realistic project to throw money at.

Also note that the scales are very different - Manhattan produced a handful of atom bombs and Apollo produced a couple dozen rockets and capsules. Any solution to our energy problem is going to require at least thousands, probably tens of thousands, of generating plants, all with massive infrastructure. That means that if we want to actually offset CO2 emissions fast enough, we need something that works now, not something that might work at some point in the future, and nuclear fission is the only possible solution. We don't have time to figure out how to make something new work and then start a build-out.

I don't want to spend a lot of time getting into specifics here, but there's a reason why solar and wind power aren't replacing conventional power at a significant rate, and it sure isn't some imaginary oil company conspiracy.

"I don't want to spend a lot of time getting into specifics here, but there's a reason why solar and wind power aren't replacing conventional power at a significant rate"

Sorry, did you miss the news?

http://www.skepticalscience.com/michaels-mischief-2-opposing-climate-so…

"The U.S. solar power market grew a record 67% last year [2010], making it the fastest-growing energy sector"

"America's wind power industry installed 1,100 MW of new capacity in the first quarter of 2011 alone and entered the second quarter with another 5,600 MW under construction, the American Wind Energy Association (AWEA) reported today. The under-construction figure is nearly twice the megawatts that the industry reported at this time in both 2009 and 2010; moreover, two-thirds of those megawatts are already locked in under long-term power purchase agreements with electric utilities, indicating an enduring industry that has proven both nimble and strong through a range of economic and policy conditions."

The reason why wind and solar power isn't replacing conventional power at a significant rate is because you're not looking at what's going on.

See this report

The Church of England has used a meeting of global faith leaders and UN Secretary-General Ban Ki-moon to launch an environmental strategy for the next seven years.
The gathering took place on 2 November in Windsor and discussed commitments on climate change in the run-up to the worldâs political leaders meeting in Copenhagen in December.
Nine other faith groups have also made specific plans for their contribution to the struggle against human-assisted global warming.

Note also that Catholics are by far the largest Christian denomination.

They are by far one among hundreds.

They are also ignored by those against evolution.

So why is that?

I say religion.

You say "the pope says otherwise", but he's not THEIR faith. He's merely the pope.

But if you know why, then say. Your posting of the same ignored statement doesn't mean it isn't religion driving them.

We all know that congress has found a solution to the problem: Defund any program that generates accurate temperature data (like those replacing failing weather satellites). No data, no man made global warming, no problem; just like with the budget, it's not going be a problem before they got to enjoy their social security benefits.

"The Church of England has used a meeting of global faith leaders and UN Secretary-General Ban Ki-moon to launch an environmental strategy for the next seven years."

psmith: Note also that Catholics are by far the largest Christian denomination.

Yes. Note that the CofE isn't the RCC.

Note too that their religion and the pope are not the same thing.

#24

I actually didn't state my own position, because my own position is pretty much that of a coward. I don't believe enough in alternative energies to think they will solve everything, and I well aware that fuel is not sustainable, so basically I am just waiting for doomsday, with no real suggestions for solutions. (Nuclear? Maybe? Just a stopgap?)
I think we might be heading for a Malthusian catastrophe.
By the way, I am not from US. From Israel.

#29

"Tell me, how much is your life, and the life of your extended family, worth?"

Well, lots! That's why I'm having this discussion. I am very interested in the solutions.

"To supply 100% of the planet's energy needs you need solar panels 230km on a side. That's all. In what way is this hard to accomplish?"

Since I am a geek, let's work that out - The sun directly overhead gives 1kW/m^2. According to Wikipedia, world's power consumption is 1.5*10^13 W. Solar panels, from what I know, are 20% efficient. So, 230km^2 * 1kW/m^2 * 20% = 1.1*10^13 W - hey, that's just about enough! (If any of my numbers are wrong, please tell me!) But hey, the sun isn't shining directly overhead 24 hours a day... And we better build this thing very near the equator. We'll at least need twice as much area, which is about 106,000 km^2, which, for scale, is somewhat less than the area of the entire New York State (or, hey, just 1% of the Sahara desert).

As for price - umm, I can't seem to find the price of PV per area, help appreciated here. I found some odd website which mentions 80 USD for 1m^2. So, assuming that, for our 100,000 km^2 area, cost comes out 8 trillion USD (just a one time cost).

I'm in favor! 8 trillion USD, 1% of the Sahara, some HVDC to move the power around, and we can power the entire world. But I think you underestimate when you say "what's hard here". I don't expect this to be easy.

"Someone else recommended it. They didn't know that the maths were fiddled to make renewables impossible, since the writer wants nuclear power to be the next big thing. His paper is a hatchet job, asserting that it is not what it in actual fact is: a load of hot air."

I'm very interested! Can you give me some reference? (from what I recall from the book, he wasn't so much in favor of nuclear...)
(I'm a bit confused you called it a "paper". "Sustainable Energy: Without the Hot Air" is a book, by David MacKay. Are we talking about the same thing?)

The other reason people are denying global warming is that the consequence of global warming is that our lifestyle is not sustainable. There are people who hear global warming and think "I can't live without my car. Anything that claims I have to is a Communist/fascist/Muslim/alien plot." It's a weird form of affirming the consequent:

"If global warming is a lie, we don't have to change anything." They believe, or want to believe, that we don't have to change anything, so they conclude that global warming is a lie. The problem is that they don't actually know that we don't have to change anything. (That we might need to change things even if global warming wasn't happening is a separate problem.)

Congratulations. You've described the greenhouse effect. Yay.

Now explain the feedback loops that cause the Earth to warm more than 1 K per doubling of CO2. Difficulty: get the cloud part right. And then explain why there will be mass extinctions and end of human civilization within 100 years because CO2 hit 500 ppm.

When you've done that successfully, then I'll start crapping my pants and begging to pay double or triple for everything.

Holy shit! Juice is a fucking moron!

By Ema Nymton (not verified) on 31 Aug 2011 #permalink

Is there an accepted explanation for changes in global climate change into and out of the medieval warming period?

BTW, I am a climate change skeptic and I'd be happy to tell you all why. I remember during the 70s it was predicted that there would be an ice age. I remember during the 80s that some were saying that warming was supposed to have ended the world as we know it already. Climate change is a very complicated long term multi-factor problem. It's not so easy to bench this in a lab, eh? Computer models = garbage in, garbage out. Those who would vehemently paint all skeptics as idiots should take a closer look at their own objectivity.

It is not hard to remain a skeptic when all the other side has to say is "you are an idiot, can't you see what the CO2 does, you need to listen to us and make drastic changes to your lifestyle, the world is going to really end this time if you don't..." yada yada

So, why did the earth warm in the past? Answer me that. Why did it warm in the past, and where is the proof that today's warming is caused by industrialization and not caused by the same processes that caused warming in the past?

Juice @43,

Not being a climate scientist myself (and not being interested in becoming one), I can only listen to what those who do the climate modeling professionally have to say. The last I heard, the best estimates they were coming up with were somewhere between 3-4 °C of warming per CO2 doubling, with the "best-case-scenario" models leading to just under a 2 °C rise and the "worst-case-scenario" models showing around a 7 °C rise per doubling.

An easy estimate is to simply look at the graphs above: CO2 has gone up by about 35% and the temperature has risen by about 0.8 °C over the past 130 years.

No one (that's sane) is contending that it will bring about the end of human civilization, merely that it will cause rapid worldwide changes in ecosystems (which are happening already), tremendous worldwide changes in agriculture (which are happening in many places, though thankfully not everywhere), and sea level rises that will make many of the world's largest cities uninhabitable (the physics of which is absurdly simple).

But it was my intention to describe the greenhouse effect; people still don't understand that this happens, and this is one of the simplest arguments I've come up with to explicate it.

@Mike:

The majority of papers during the 70's were actually about climate change and warming. The popular press (Time Magazine) put out an article about global cooling and that is all that laymen remember.

The 80's: You'll have to cite something. Most of the climate change papers from the 80's have to do with particulate reduction as well as N2 and CO reduction in urban areas.

Computer Models: You have a fine opinion, which has no scientific basis.

Past warming: Wasn't global (Mann, 2009). There was also a cooling in other areas that created an offset. From everything I've read, the warming was largely in the northern hemisphere, which created a feedback loop from thawing permafrost and reductions in arctic ice (fresh water). www.meteo.psu.edu/~mann/shared/articles/MannetalScience09.pdf

@JayK

I trust your point about the 70s. I was young then, and magazine covers are about all I remember. Gosh, those articles still float out once in a blue moon, too - about how an ice age can swoop over us in a matter of a couple of decades. Probably just to scare people.

My reference to "end of the world" talk in 80s was prompted, I am sure, by the politicization of this issue, which started occurring at that time. That is a horrible disservice to the science of what is going on. It really affects the credibility of it all when celebrities and politicians are obviously trying to scare people. I don't know that scientists were at fault there.

I don't concede the point on the computer models. I am a computer programmer. A model is a computer implementation of a set of assumptions and/or rules run against a bunch of data. The model is only as good as the rules. Garbage in = garbage out is a computer truism, and has been for years. I can make you a computer model to show you anything you want. Seriously.

I trust that models are getting better, but this is still a wicked complicated system. I wonder what the quantifiable margin of error is when you have dozens of factors that you know about, and perhaps some that you don't, in a system that you can't test so easily.

And my big question: How can it be known that factors triggering the medieval warming period aren't also at work today? Do we understand the natural rhythms of our climate enough? What about the match behind the affects of all the numerous natural processes that seem to be involved - CO2, other gases, clouds, currents, algae blooms, volcanoes, solar cycles, axis wobble, etc. The models get reduced to math, based on observations and guesses. So many factors in those models. In light that there appears to be natural rhythms (ice ages, et al) how do we know that man-made CO2 is the real cause of the current climate change.

I just don't see the science as 100% solved. It seems they really want me to believe what they really believe... But I'm an engineering type person, and I'm not convinced so far.

So do you all think I am whacked?

"I remember during the 70s it was predicted that there would be an ice age."

No, no it was not. There were (if memory of reviews serve me) a couple articles in magazines that talked about cooling, but the type of thing you imply - the body of scientific research saying OMG We're All Going To Freeze didn't happen.

"Computer models = garbage in, garbage out."

It can be, but with a variety of models from different sources giving similar results, that does not seem to be the case here. There is also good work being done to combine predictions from different climate models - as one recent example I'd suggest you look at the work Noel Cressie and his group at Ohio State are doing.

You have strong opinions. Many people do. A major difference is that you don't have any evidence on your side for support of yours. Just a question: what area of study have you done that gives you the knowledge to summarily dismiss the models? Healthy skepticism is good, but unless you can base it on, you know, knowledge, and give intelligent critiques of the issues, you aren't a skeptic, you're only a denier.

@JayK:

I read the article at www.meteo.psu.edu/~mann/shared/articles/MannetalScience09.pdf about the medieval warming period. Or tried! I didn't do any follow-up on their statistical sampling methods, etc. I noted where they had 1000 samples over 1500 years from multiple sources and used the last 100 years for calibrations. Sounds like they did the best with what they had. They seemed to explain these climate events in terms of similarities with la nina and ocean oscillations. It doesn't seem terribly authoritative when it comes to answering 'why?' This paper seems to quantify those events and describe how they fit existing models.

@dean:

I'm not a climate scientist. I don't think that should rule me out of the debate. Particularly when it is a political issue.

I did comment on the computer models. I have almost 30 years experience working with computers, most of those programming. I understand computers. I am curious about how those models work. I've heard quite a bit of tuning and fudge goes into them.

I'd like to give you a bit of advice. Science needs to do a better job of convincing people like me before I'll buy into making big economic changes over this. You say I am a denier like it is some kind of heresy. With that attitude all I have to say to you is: stick and stones, buddy. I'm still a skeptic. That's what I do. Are you a climate scientist? Can you point me - a layperson like billions of others - towards an answer to my question: Why did the medieval warming period happen? What is different between now and then? What about the ice ages? How do you know we are not rocketing into or out of an ice age? Ice ages were going on for tens of thousands of years. These are common sense questions - basic troubleshooting. Does climate science have good answers? If they don't, then I don't consider the science to be anywhere near done.

Explain or point me in the right direction. Something better than "you are not a scientist. you are a denier..."

Mike: in the 60s and 70s there was increasing pollution that reduced the light hitting the ground, lowering global temperatures. There was also a report that, if all else remained the same, natural variations in the earth's orbit (responsible for the last ice ages) would, in 15,000 (or possibly 120,000) years, put us in another ice age. These two things were confused, the assumptions and the time scale were ignored and the popular press reported it as 'New Ice Age Imminent!' What actually happened was that a lot of the pollution was cleaned up so we no longer have as much short-term cooling effect and the rise in CO2 has overwhelmed the effect of the Milankovitch cycles.

Meanwhile in science, it was generally expected that the CO2 effect would come to dominate and that a warming trend would be visible by the end of the century.

Computer models = garbage in, garbage out.

Why do you assume that climatologists are incompetent? If you had any decency you would either back up this claim of 'garbage in' or apologise.

where is the proof that today's warming is caused by industrialization and not caused by the same processes that caused warming in the past?

Science does not deal in proof. If you mean 'how good is the evidence', the basic physics and chemistry have been established for at least 50 years and should be easy to find on the internet. Search for 'physics of global warming' and pick a link that matches your level of expertise.

By Richard Simons (not verified) on 31 Aug 2011 #permalink

Thanks Ethan -- that is one of the best description of the CO2 problem that I have seen. It is really accessible.

Several things I would add:

1. The amount of energy the earth radiates into space is equal to the amount of energy it absorbs from the sun. We are in basic equilibrium. This means that when measured from space, the earth will radiate away the same amount of energy as a black body with a temperature of 255 C.

2. The reason that the surface is warmer than 255 C is the adiabatic lapse rate. Air cools as rises and warms as it sinks. (It is called the adiabatic lapse rate, but it deviates slightly from the perfect gas law for reasons that are a bit too complex to go into here). With the earth (and all planets), it is the adiabatic lapse that creates the thickness of the blanket keeping the surface warm.

3. Adding CO2 to the atmosphere raises the elevation in the atmosphere where CO2 radiates infrared energy into outer space. This is called the transparency point for CO2. This is the point where CO2 becomes optically dense for those IR wavelengths it absorbs when viewed from space.

4. The raising of the transparency point for CO2 will raise the location of where the Troposhere (lower atmosphere) ends and the Stratosphere begins. This is the point the transfer of thermal energy via the adiabatic lapse rate stops. This boundary between the Troposphere and the Stratosphere is called the Tropopause.

5. It is this increased thickness of the lower atmosphere that causes the increase in earth's surface temperature. It is the lower atmosphere which acts like a blanket. It slows the transfer of heat absorbed by the earth's surface from radiating away into space

6. Venus has a hugely thick lower atmosphere. Most of the solar flux is absorbed near the top of the atmosphere. The air from above sinks and warms making the fiery surface temperature (plus of course some solar flux getting down to the surface).

7. The funny thing about the adiabatic lapse rate is that the solar flux can be absorbed by the atmosphere as in the case of Venus, or by the surface as in the case of the earth, and in either case, the surface gets hotter.

8. Of course there are lots of complications like (a) water vapor absorbs a lot of the IR spectrum and the add temperature from CO2 will cause more evaporation which would normally warm the earth even more (this is called a positive feedback loop); and (b) it also produces more clouds which reflect sunlight away from the earth (this is called a negative feedback loop). These complications are what we pay climate scientists to study and run computer simulations about.

Bottom line, unless the laws of physics have suddenly changed, adding CO2 to the atmosphere will increase the temperature, but exactly how much is more complicated and requires modeling and computer simulations.

"6. Venus has a hugely thick lower atmosphere. Most of the solar flux is absorbed near the top of the atmosphere. The air from above sinks and warms making the fiery surface temperature (plus of course some solar flux getting down to the surface)."

In fact, the light on the surface of Venus is about the same as an overcast Earth day. It's still very bright under all that cloud.

"Is there an accepted explanation for changes in global climate change into and out of the medieval warming period?"

Yes.

http://en.wikipedia.org/wiki/Medieval_Warm_Period

Of course, YOU may not accept it, but then you never liked science.

"I remember during the 70s it was predicted that there would be an ice age."

http://www.youtube.com/watch?v=XB3S0fnOr0M

"I remember during the 80s that some were saying that warming was supposed to have ended the world as we know it already."

Who?

"Those who would vehemently paint all skeptics as idiots should take a closer look at their own objectivity."

Those being called idiots should look at their own objectivity to see if the charge is correct.

"So, why did the earth warm in the past? Answer me that."

CO2.

http://blogs.nasa.gov/cm/blog/whatonearth/posts/post_1262067702260.html

"and where is the proof that today's warming is caused by industrialization and not caused by the same processes that caused warming in the past?"

http://www.skepticalscience.com/empirical-evidence-for-global-warming.h…

Or short version: we're putting CO2 in the atmosphere.

Prove it's not changing the temperatures this time when it has done so in the past.

"Is there an accepted explanation for changes in global climate change into and out of the medieval warming period?"

Yes.

http://en.wikipedia.org/wiki/Medieval_Warm_Period

Of course, YOU may not accept it, but then you never liked science.

"I remember during the 70s it was predicted that there would be an ice age."

http://www.youtube.com/watch?v=XB3S0fnOr0M

"I remember during the 80s that some were saying that warming was supposed to have ended the world as we know it already."

Who?

"Those who would vehemently paint all skeptics as idiots should take a closer look at their own objectivity."

Those being called idiots should look at their own objectivity to see if the charge is correct.

"So, why did the earth warm in the past? Answer me that."

CO2.

http://blogs.nasa.gov/cm/blog/whatonearth/posts/post_1262067702260.html

"and where is the proof that today's warming is caused by industrialization and not caused by the same processes that caused warming in the past?"

http://www.skepticalscience.com/empirical-evidence-for-global-warming.h…

Or short version: we're putting CO2 in the atmosphere.

Prove it's not changing the temperatures this time when it has done so in the past.

"Difficulty: get the cloud part right."

That's what a GCM has. Here's one for you:

http://www.giss.nasa.gov/tools/modelE/

"And then explain why there will be mass extinctions and end of human civilization within 100 years because CO2 hit 500 ppm."

What happened to the coastline last time we were at 500ppm?

Oh, that's right: flooded.

Now, New Yorkers may find this slightly more worrying that "inconvenient". In fact, since the TEMPORARY flooding of New Orleans was considered a "Catastrophe", that seems to indicate a catastrophe here too.

"Since I am a geek, let's work that out "

Already been done:

http://www.realclimate.org/index.php/archives/2009/10/an-open-letter-to…

"As for price - umm, I can't seem to find the price of PV per area, help appreciated here."

Solar PV is the most expensive, but it's getting to be $1/W now.

The link I gave you earlier shows how the cost has gone down.

So your requirements would be 10 trillion dollars. A one-off payment, mind.

That's less than one fossil fuel company's turnover for a year!

"I'm very interested! Can you give me some reference? (from what I recall from the book, he wasn't so much in favor of nuclear...)"

Well of course. He can't SAY "It's lovely, is nuclear, lets go for it" since he proclaims he's got no pony in this fight and so he has to rely on excluding everything else but nuclear.

When only one option remains, there's no need to promote it directly.

Take, for example, his calculation on the energy density.

FOR NO REASON he uses a windfarm as entirely used AS A WINDFARM. I.e. no moo cows underneath. Then, because of this, he proclaims that 10% of the land area of the UK is the maximum, since we can't waste more than that on just power.

Fail number 1. We can farm under a wind turbine quite well.

Then he uses a smaller turbine. We have 75Mw turbines now. He uses 5 or 15MW ones.

Fail number 2.

After this cherry picking he then finds that we CAN produce our energy needs, so FOR NO REASON, he reduces the value again.

And now he's "proven" wind can't do it.

Fail number 3.

Then he forgets we actually DO get sunlight here in England.

Fail number 4.

"FOR NO REASON he uses a windfarm as entirely used AS A WINDFARM. I.e. no moo cows underneath. Then, because of this, he proclaims that 10% of the land area of the UK is the maximum, since we can't waste more than that on just power.

Fail number 1. We can farm under a wind turbine quite well."

In anecdotal support of this: a rural area of western michigan has a large number of turbines that coexist nicely with several farms. Most (not all, but most) of the landowners were quite pleased with leasing land and having neither to have it drilled for natural gas/oil or mined for gravel or other purposes. Are they noticeable on the landscape? Sure. I think they look cool, and when framed against a barn or collection of farm buildings they are great photo opportunities. I'm also sure some people do not like to see them. Point being: the farm land around and under them is still in use.

@wow:

(I very much appreciate the links, from you and others. I have been trying to read them all. This is such a blowout of an issue and can take so much time, I don't know how much more I can dive in right now. I do keep up with this topic and as time goes by I can see the science becoming better over the years. I'll look more into the computer models. This issue is too politicized. It's as bad as religion - i.e. those who would tell me to that I can't prove AGW wrong and therefore it must be right! Beyond all that BS does lie hard science. Interesting, complicated new science! I like keeping the discussion on that level.)

I read the material you linked to about the medieval warming period being caused by CO2:

http://en.wikipedia.org/wiki/Medieval_Warm_Period
http://blogs.nasa.gov/cm/blog/whatonearth/posts/post_1262067702260.html
http://www.skepticalscience.com/empirical-evidence-for-global-warming.h…

The first link offers no explanation, just a quantification of when and how warm.

The second link (I could not watch the video at work) - the summary states that this is about CO2 being the biggest factor going into climate change.

The third link state that humans are putting more CO2 into the atmosphere, CO2 traps heat, and it is getting warmer.

All together, they DO NOT explain the medieval warming period. If I take the above all as true (which I am willing to do at this point) I still do not have an explanation for the medieval warming period. The closest I get is CO2 causes all global warming, and must have caused the MWP. Do we have measurements of CO2 from that time, from ice cores or anything? Why did CO2 increase at that time? If CO2 did not increase during the MWP, what other factor(s) then caused the warming? If CO2 did increase, where did it come from? There was no industrialization then. If the climate could change so drastically in only parts of the world, how so? If we don't understand all of that complexity, how can we say that we definitely understand what is happening today? How do we know that human CO2 output is causing todays changes? How do we know todays climate change is not driven by a 500 year solar cycle, and/or multiple other factors (ocean currents, ice caps, feeback mechanisms, etc). How do we know that decreased human CO2 output will make enough of a difference to stop climate change?

All of these seem like reasonable questions to me.

I'm not sure why Mike ignored the paper I included, which explained that the MWA was not global and was limited to regions in the Northern Hemisphere. He also ignored that there was higher CO2 levels due to thawing permafrost (also lakebed emissions).

How do we know that CO2 output is causing today's changes? This is known as spectral absorption. Different gasses absorb and 'trap' different wavelength radiation. As UV energy travels through the atmosphere, relatively untouched (except for ozone), it strikes the earth and is converted to heat (infrared) energy. This energy is released back as infrared wavelengths. Carbon dioxide absorbs (traps) infrared wavelengths. We can measure the effect of increased CO2 in the atmosphere through energy balance equations from the ground, or more simple ones by satellite. The energy balance by satellite shows that less infrared is going out into space than UV energy is going into the atmosphere. That change in balance is correlated directly to increased CO2 densities in the atmosphere.

Here is one paper from 1968, you know, when you think all of those cooling papers came out:
www.meteo.mcgill.ca/~tremblay/Courses/ATOC530/Sellers.JAM.1969.pdf

And another from 2010:
Lacis, A. A., Schmidt, G. A., Rind, D., & Ruedy, R. A. (October 15, 2010). Atmospheric CO2: Principal control knob governing earth's temperature. Science, 330, 6002, 356-359.

"How do we know decreased human CO2 output will make enough of a difference to stop climate change"
We don't. We may have already tipped the balance and have caused enough positive feedback that the system becomes chaotic and our changes have little effect. Then again, I might just be a fatalist. Cleaning the environment now, however, may give us more time to develop technologies that further reduce our emissions.

"I'm not sure why Mike ignored the paper I included, which explained that the MWA was not global and was limited to regions in the Northern Hemisphere."

That would be because it "explained that the MWA was not global and was limited to regions in the Northern Hemisphere."...

"All together, they DO NOT explain the medieval warming period."

That's because they are NOT all explaining the medieval warming period.

YOU asked several questions. THEY answer those questions.

The MWP wasn't global:

"The Medieval Warm Period ('MWP),Medieval Climate Optimum, or "Medieval Climatic Anomaly" was a time of warm climate in the North Atlantic region"

(First link).

And within the first link, the link to the LIA, that the LIA was not global:

"However, the timing of maximum glacial advances in these regions differs considerably, suggesting that they may represent largely independent regional climate changes, not a globally-synchronous increased glaciation. "

And, since the end of the MWP was caused by entering into the LIA, the answer as to why we came out is the reason we went into the LIA, which is:

"Several causes have been proposed: cyclical lows in solar radiation, heightened volcanic activity, changes in the ocean circulation, an inherent variability in global climate, or decreases in the human population."

http://en.wikipedia.org/wiki/Little_Ice_Age#Causes

And a quick google can give you further links about why the regional MWP existed:

http://www.britannica.com/EBchecked/topic/175842/medieval-warm-period-M…

Given the ease of finding answers, why did you not look?

Mike: This issue is too politicized.

Yes, it's because political hacks keep coming up with BS like this:

Mike: It's as bad as religion - i.e. those who would tell me to that I can't prove AGW wrong and therefore it must be right!

Nope, you can't prove your assertion is correct, therefore you are wrong. Come back when you can prove your assertion is correct. Your complaint is political rhetoric, NOT scientific inquiry. A scientific inquiry would go "If I can't prove my theory correct, then it's wrong".

#59

"Solar PV is the most expensive, but it's getting to be $1/W now."

I got confused here, wasn't sure what "$1/W" is supposed to mean, if most of the cost is in a one-time investment. I understand it now, I think - building a PV farm, which is capable of giving 1kW (on average? on peak?), would cost $1000.

As for the book, it has been a few years since I've read it, so I'll have to re-look to check some of your points. One thing I do explicitly remember, is him mentioning that the size of the wind turbines doesn't matter, in that if you make em bigger, you have to place them further apart, and the physics works out that it doesn't matter (further calculated in the technical appendices). BTW, from his blog, I remember him saying he loves wind and thinks it's one of the best for Britain.

In general, do you think these fails kill the numbers (and conclusions) of the entire book? Or are they minor fixes? (I can personally say that I didn't come out of the book thinking "yay, nuclear is our only hope", so, if that was his goal, it wasn't terribly successful)

BTW, can you suggest another forum where we can continue this discussion (if you'd like)? Blog threads have a tendency to die out quickly...

Ethan
Excellent and simple explanation.

@16, @17 Ethan
Yes, yes.
And even Ethan gets caught in his spam filter.
I do to sometimes.
But I thank him for his effort. Just imagine what he keeps out. Yes double thank you.

@14 Stu
Yes!

@19 Bill
Very nice point, I accept global warming; which probably accounts for the fact that I didn't get the memo. Thanks.

Ethan, you can be as careful and try as hard as you want, and that certain sector will simply feel compelled to resist the idea (not to be confused with those wondering, just how much effect considering uncertainty in forcing factors, other cause/effect, etc.)

As someone who got their major in Earth Science, and has worked with geologists, the people who study this stuff, I do not believe in "global warming" but do believe that the Earth goes through natural climate change all throughout its history. I don't think humans are quite as big a deal in this whole thing, I think we're thinking pretty big of ourselves about a planet that millions of species have lived and died and gone extinct compared to the short amount of time we've lived here. I think that we can pollute, but if we do cause something so bad that people die out, the Earth will heal itself and new forms of life will evolve to replace us. As for the NASA data, what about this article? http://news.yahoo.com/nasa-data-blow-gaping-hold-global-warming-alarmis…

Please,

Stop with this nonsense.

"The blanket is going to absorb the heat your body is radiating".

...

@Hans, your math and view is OK.

Hannes, are you denying that blankets keep you warm?

Ethan, you said

"You are postulating that an atmosphere will be at a temperature Ta that is in between Ts and 0, and then stating that the thing at Ta cannot make Ts hotter."

Yes, as the example here.

"It isn't about the difference in temperature between the layers, it's about heat. If you can understand the heat, the temperature comes easily."

Yes an energy generating source builds up temperature, but then you need a temperature difference to get the energy transported elsewhere. This gradient sets the net flux (=e*sigma*A(T1^4-T2^4). With earth receiving a fixed flux from the sun, how can T2 (earth) change if T2 is set by radiation only?

"The Sun emits heat, the Earth holds it for a time, and then re-emits it into space. The total amount of heat on Earth at any given time determines its average temperature.
With me?"

Yes

"This is the calculation you did for Earth to arrive at your original Ts. The calculation is done here on wikipedia, where they arrive at a temperature for Earth of about -20 Celsius.
Now, this is for a planet without an atmosphere"

It is with an atmosphere, you can see this as the albedo used is 0.3.

"Add an atmosphere in, it holds the heat in for longer. That means more total heat on Earth at any given time, because it's got the Sun's heat that it had in your Ts calculation, plus a few percent of the heat from an earlier time, plus an even smaller percent of the heat from an even earlier time, etc. Hence, the temperature now is hotter than your calculation gave for Ts."

Yes, so you agree it's not about the radiation but about a heat capacitor at work. Greenhouse gasses can't hold radiation.

This comes closer to what I have in mind, the atmosphere retains heat (as thermal motion, by SW absorption and surface/ocean interactions) but there cannot be a heat effect from a radiative blanket with a fixed flux.

But the real heat capacitor is the oceaan covering 70% of earth. Radiation will be absorbed up to 100 meters deep, and this does'nt get emitted (right away) and that's where the energy buid up occurs. A lot of this heat also has to work it's way out through the insulating atmosfeer.
So ocean and atmosphere act as a imaginary greenhouse, delaying emission of incoming radiation by transfering it in thermal motion in a huge capacitor.

Wow @27

Yes, it's net radiation reducing as dT declines
Yes, any body above absolute zero radiates energy.
Yes, that cooler atmosphere will radiate to the warmer earth.
But still earth surface will not get warmer

"What happens when you increase the thermal energy input into a body, Hans?"
We both know that answer, but where do you think does energy above that from the sun emerges from then?

Hans@74: What do you think happens when the rate of energy going in stays the same, while the rate of energy going out decreases?

While I do not fully disagree, there are still facts that science overlooks in creating the value of human intervention of global temperature. For instance, is the proximity of the sun (we are the closest we have been in many centuries) responsible for any increase? Or, hasn't the earth been warming since the last ice age? How did man do that one? Not to mention all the just plain bad science we have to deal with daily. Daily temps are up because nightly temps are up, in populated areas. What about the unpopulated areas? NASA has (without trumpets blaring) a thermal model that indicates the global temp increase is less than one third of what popular science claims. So, who is correct?

Conserve, recycle, re-use and give it up. Man is to infinitesimal to damage the earth, we can only destroy ourselves.

By Mark McCurley (not verified) on 01 Sep 2011 #permalink

Tristan@75
The energy going out can't decrease. Energy in = energy out, photons don't know time.

I made an error in my analysis @52. For the Venus system to work, some solar energy needs to make it to the surface. Not much does. Maybe 5 to 10% of the visible spectrum, and virtually 0% on the remainder of the solar spectrum. Still, this is more than enough to power the adiabatic lapse rate.

Some energy will be transferred upward via radiation instead of adiabatic expansion, but not much, and it will be frequency specific.

to #35

Looks like you're mixing several different issues together in a confusing way. If we're talking about Global Warming, then CO2 emissions are the only issue

Not exactly, coal generates slightly more C02 than oil. Natural gas about half as much.
Just as importantly, you shouldn't over simplify, the fuel you choose has effects apart from GW, coal is generally worse than oil in terms of overall pollution, so I want to distinguish between oil and coal as a result.

Manhattan project... I see these types of ideas a lot from people who aren't engineers

Until now, I guess. I agree that you can't start to build something until you know what direction to go into, but, so find the direction, this is a big deal, there are many avenues that need to be tried, we need a DARPA type program for energy that funds hundreds/thousands of little projects and filters up the most promising ones. We need leaders in government directing a plan that has tax incentives for developing new energy technologies ( we had this in the eighties and all sorts of weird/fun technologies were tried, but they went away because not enough time was permitted for these to flourish before the tax benefits were eliminated), free education for the brightest scientists and engineer candidates who work on energy technologies for the first N years after their undergrad,grad and Doctoral work. I could keep going but you get the picture. Rather than being a drain, this kind of approach would most likely be a net benefit to the economy.
if we want to actually offset CO2 emissions fast enough, we need something that works now, not something that might work at some point in the future
The problem with this statement is that you conclude that since we don't have anything now, we should do nothing, which means on average a 2% yearly increase in energy consumption.
and it sure isn't some imaginary oil company conspiracy. Except for the lizard people running the government, and the fact that the 911 truthers planted Obama's birth certificate in Roswell, I don't go much for conspiracy theories. Take these for what they're worth, the photons they are written on ( metaphorically )

http://www.ucsusa.org/news/press_release/ExxonMobil-GlobalWarming-tobac…

http://www.guardian.co.uk/environment/2009/jul/01/exxon-mobil-climate-c…

By Bill Minuke (not verified) on 01 Sep 2011 #permalink

While there are no panaceas, natural gas would seem to be a good transitional fuel away from coal/oil. Yes methane is also a green house gas. We do use it currently and it contributes to GW. Even so every joule of energy we generate with natural gas produces 1/2 of the C02 that coal/oil does. So it's a step in the right direction.

My guess is that reducing carbon emissions won't be via one big break through, but, lots of smaller steps. (Even so a fusion powered flying car would be nice.)

By Bill Minuke (not verified) on 01 Sep 2011 #permalink

Hans @78: well, there's your problem. At equilibrium, energy in = energy out. In general, however, the energy balance equation is (rate of energy accumulation) = (rate of energy in) - (rate of energy out). An atmosphere which is transparent to visible light while capable of absorbing and re-emitting and/or reflecting infrared light reduces the rate of energy out while leaving the rate of energy in unchanged - thus leading to a net accumulation of energy, and hence increase in temperature. This increase in temperature in turn increases the rate of energy out; the temperature will thus increase to eventually reach a new equilibrium where the rate of output once again equals the rate of input.

"Yes methane is also a green house gas."

It can be produced from biotic sources as opposed to fossil sources.

We can cut energy requirements 40% and see no problems or reductions in "quality of life" (unless your life is meaningless without an SUV).

Solar and wind are excellent replacements and, since the supply more closely matches demand, we don't need the overproduction of energy to have a load-match reserve to spin up on demand to anywhere near the same degree, reducing our "nameplate capacity" even further.

The only problem for the man-in-the-street with renewables is that they appear to be eco-hippy nonsens and that won't do: if they agree to these power sources, they'd be agreeing with eco hippies!!!

"For instance, is the proximity of the sun (we are the closest we have been in many centuries) responsible for any increase?"

No.

Part of the reason is that we're moving away from the sun over the recent centuries. Another part is that it is a lesser effect than the location of the landmasses at aphelion and perihelion.

"Or, hasn't the earth been warming since the last ice age?"

No, we're leaving the last ice age and are due (as in long past the midway point of transition) to enter a new ice age.

The other reason why not is that the temperature doesn't rise "because we're leaving an ice age", the causation is "we leave an ice age because temperatures are increasing".

"How did man do that one?"

He didn't. However, there is evidence of species extinction millions of years before man. So how did man mange to make the Dodo extinct?

Therefore the question is pointless.

"Not to mention all the just plain bad science we have to deal with daily."

Yes, indeed. However, you seem to have not only brought that bad science into your life, you're also ensuring its promulgation in your post.

It's the plain bad science that is trying to throw confusion over the fact of AGW.

"Daily temps are up because nightly temps are up, in populated areas."

Daily temps are up because the daytime temperatures are up too.

"What about the unpopulated areas?"

It's the same there. Nighttime temps up, daytime temps up.

"NASA has (without trumpets blaring) a thermal model that indicates the global temp increase is less than one third of what popular science claims. So, who is correct?"

Unless you tell us what model you're on about, who can say?

However, I can say that YOU are incorrect: There is no model that says that.

"One thing I do explicitly remember, is him mentioning that the size of the wind turbines doesn't matter, in that if you make em bigger, you have to place them further apart"

This is wrong too.

The turbine is VERTICAL.

The actual figures don't accord to that either: the power of a bigger turbine goes up faster than the shadow does.

"BTW, from his blog, I remember him saying he loves wind and thinks it's one of the best for Britain."

But he says it can't be used for Britain. At least one of those statements is wrong.

"In general, do you think these fails kill the numbers (and conclusions) of the entire book? "

Yes.

Yes an energy generating source builds up temperature, but then you need a temperature difference to get the energy transported elsewhere. This gradient sets the net flux (=e*sigma*A(T1^4-T2^4).

Yup. It's made of two parts:

e*sigma*A*T1^4 leaving the hotter body, cooling it
e*sigma*A*T2^4 leaving the cooler body and warming the hotter body.

"With earth receiving a fixed flux from the sun, how can T2 (earth) change if T2 is set by radiation only?"

Because you're deliberately getting the bodies wrong.

T1 = earth's temperature
T2 = atmposphere's temperature.

YOUR version has the earth warming up the Sun!

Which IS true, but if your complaints were genuine, would be FAR more ridiculous.

"Yes, so you agree it's not about the radiation but about a heat capacitor at work."

And how does that heat capacitor work? It radiates energy. To the earth and outside, whereas before, without a "capacitor", the earth just radiated outside.

This means that with the capacitor, you now have extra radiation coming in to the earth.

What happens when you increase the energy a body absorbs, hans?

"Yes, it's net radiation reducing as dT declines"

But we're putting energy into the earth's thermal resevior: it's called "the sun's radiation". You may have noticed it, it's the big burny hot bright thing in the sky during the daytime.

Therefore dT doesn't have to decline.

"Yes, any body above absolute zero radiates energy."

Well done.

"Yes, that cooler atmosphere will radiate to the warmer earth."

Good. We're getting close to the truth now.

"But still earth surface will not get warmer"

Why not? The earth was getting the sun's radiation before and now it's getting the sun's radiation AND the atmosphere's radiation.

Maybe you think 1+1=1.

""What happens when you increase the thermal energy input into a body, Hans?"
We both know that answer"

I don't think we both know.

YOU, apparently, think that when you increase the thermal energy input into a body, it DOESN'T get warmer. You just said that a sentence earlier, in plain old black and white!

"but where do you think does energy above that from the sun emerges from then?"

Could you try that in english?

The closest I can render it into actual sense is: "where you do think the energy above that from the sun comes from?", the answer to which is: the atmosphere.

It IS at a temperature, correct, Hans?

It's above absolute zero, correct, Hans?

And haven't you agreed that a body above absolute zero will radiate energy, Hans?

Therefore that extra radiated energy above that produced by the sun comes from the atmosphere surrounding the earth.

"The energy going out can't decrease.

Posted by: Hans | September 2, 2011 12:18 AM"

"Yes, it's net radiation reducing as dT declines

Posted by: Hans | September 1, 2011 10:40 PM"

Hans disagrees with Hans.

The argument ensuing should be entertaining!

"or the Venus system to work, some solar energy needs to make it to the surface. Not much does. Maybe 5 to 10% of the visible spectrum"

Reno, IIRC, the surface flux on Venus' surface is something of the order of 600+W/m^2 at midday on the equator, average something north of 150W/m^2.

Remember, Venus is quite a lot closer to the sun than we are, and the images from the venera craft show quite a lot of daytime brightness:

http://mentallandscape.com/V_DigitalImages.htm

In post #20 I asked the question what were the emotive forces that drive denial of climate change. Predictably the Atheist Fundamentalists tried to blame religion. But knee jerk responses like this are not useful discussion.

Naomi Oreskes and Erik Conway have written an insightful book, The Merchants of Doubt. This book describes how corporations have mobilised contrarian scientists to sow doubt in the public mind on a variety of issues, the latest of which is climate change. The book devotes a lot of material to the climate change denialists and is important for understanding the reasons for public distrust of climate change.

"Predictably the Atheist Fundamentalists"

You were asked for examples of such atheist fundamentalists, but were unable.

Oopsie.

You posted that the RCC said that AGW was wrong.

This is correct, they did so.

You then inferred (please correct if you make no such inference) that religion could NOT be the reason why people deny AGW.

This is incorrect.

If this is a problem for you, I would suggest that you take up my challenge and explain why AGW denial which has had senators in the USA say that AGW was false because God promised (in the chapter about the Great Flood) that there would be no more flooding.

You will need all the luck and ignorance you can find to manage that, but I wish you all the best in that endeavour.

"The Merchants of Doubt. This book describes how corporations have mobilised contrarian scientists to sow doubt in the public mind"

This isn't going to explain how those not driving corporations believe that AGW is wrong.

It doesn't even say that religion ISN'T a reason.

Just that there are a multiplicity of reasons, of which Religion is one.

As I said earlier:

Religion.

Greed.

Fear.

Self-love.

Politics.

Are reasons for AGW denial.

NOTHING you've posted denies the role of religion in AGW denial.

Maybe the problem you have, psmith, is that you asked for reasons why people deny AGW as merely a rhetorical device and do not, in actual fact, want to know why.

Because you do not wish to know that religion is a big reason why people deny AGW.

Great post, Ethan!

I've heard both religious and non-religious individuals deny climate change; the religious ones will state something to the effect of "God gave us dominion over the Earth so we can do what we like." Often these are the same individuals who have "gone forth and multiplied", so their children, grandchildren, etc. will be dealing with the consequences of their arrogance. I have scientist colleagues who also deny climate change, and their "rationale" seems to be that they don't want to have to change their behavior.

Even many of those who do accept climate change science and predictions resist modifying their behavior, particularly if it involves giving something up, or making life less convenient. No one wants to give up frequent air travel, which has a huge carbon footprint, if it's a significant component of their job, or if they just enjoy jetting around the globe for meetings and vacations. Public transportation is not a viable option for me, and I'm not willing to cycle the seven miles to work and back, because there are loads of traffic and no bike lanes (and it's been eleventy hundred degrees here for the last several months). So I continue to drive my old (though well-maintained) Honda to and from work each day. But I can see how my relatively short (compared to others in this area) commute is not sustainable in the long run, when everyone else is doing the same.

Hans, as you are fond of pointing out, the Steffan-Boltzman relationship for thermal radiation means that the power radiated (watts), goes at the T1^4-T2^4. If the quantity of heat radiated has to go up (because the Earth's surface is receiving more heat from the Sun plus re-radiated from the atmosphere), then the temperature of the Earth has to go up to radiate more heat in the same amount of time. The temperature of space is staying the same, the temperature of the Earth must go up.

"Public transportation is not a viable option for me, and I'm not willing to cycle the seven miles to work and back, because there are loads of traffic and no bike lanes"

Which is a self-fulfilling prophesy.

Particularly depressing for a nation that prided itself on it's CAN-DO! attitude, it's now "someone can do it, not me!" attitude.

Seven miles is about as far as I'd be prepared to do (a little further if it's fairly flat). And most people will manage a one-hour or even nearly 2-hour commute, so it seems like 40-minutes if you're actually doing the work is acceptable, yes?

But it won't happen.

Until americans realise that sometimes they HAVE to be told what to do. Not because they can't or won't do it, but that so many others will wait until someone else does before they do it, so everyone's in gridlock.

If they'd been less proud of a pioneer spirit, their lack in this regard might be more acceptable, but when one proclaims independence but reneges on the consequences, it's rather hypocritical.

This isn't to say that any other first worlder isn't able to improve immensely, but the USA has a sort of hate-on for changing for the sake of others.

An example is the resistance to using a "clothesline" to dry their clothes in the USA. I use it when absolutely necessary (i.e. I've run out and need a clean set of clothes in a hurry in winter, when it takes a couple of days to dry off).

Stunned amazement that a "clothesline" can dry clothes in anything like an acceptable time is the response for the vast majority of americans.

But a practice quite common in Europe.

Hans, do you and similar realize that you are disagreeing with the basic concept that a planet with an atmosphere is warmer than it would be without one - that is the basic "greenhouse effect" which is not the additional concept that *extra* CO2 has some particular effect on temperature. Almost no one denies the former, it's like evolution. The current "debate" in any reasonable sense isn't about those basics, it's "how much" effect extra ingredients in the atmosphere have, how much other things like cloud changes can modify that, feedbacks, etc. You should realize that. The Moon is colder on average (integrated temperature over time over area) than the Earth, even at same distance from Sun. Doesn't that tell you something?

It doesn't tell him something he's willing to listen to, Neil.

@Mike: Analysis of gas bubbles trapped in Antarctic ice cores prove that the current atmospheric greenhouse gas concentrations are higher than they've been at any point in the past 650,000 years. Completely swamping any consideration of the so-called MWP and so-called LIA, each of which have not to my knowledge been demonstrated to have stretched beyond northern Europe anyway.

Oded: Consider this. What will happen to the price of oil in the near future? We have passed peak oil; we are in a global recession. If the economy picks up, and Brazil's, China's, and India's growing middle class continue to want middle class luxuries, what happens to oil as it gets more difficult to produce and the demand increases? Now, please consider what happens to the price of wind and solar as the technology spreads, and demand increases - the economy of scale. As for nuclear, it is as expensive as ever. Nobody has been blocking nuclear development - not in the US anyway. It's too expensive for sane investors to gamble on. The cheaper path means moving to renewables ASAP.

And of course, (this has been covered in some posts) there is the price we all pay by a downgraded environment. Last month, in August, the US has already seen a record set on the price of damage done by weather events. And that was before Irene... I live in the border between wet and dry areas of the US; we have so far seen minimal effects of global warming here. But - ironically - the Texans are subsidizing, through drought and heat and loss of cattle and crops, the cheap gasoline that I burn in my daily commute to work. I'd rather subsidize, through taxes, their transition to solar. They have lots of sun.

The next 30 years will not go well.

Solar and wind are excellent replacements and, since the supply more closely matches demand

That's just not true in the case of wind. Wind generation is a random variable.

By Waiting for a … (not verified) on 02 Sep 2011 #permalink

> Wind generation is a random variable.

As is demand.

See again: "since the supply more closely matches demand" and reconsider your assertions.

"Nobody has been blocking nuclear development - not in the US anyway."

Not *entirely* true. The USA has been blocking nuclear development all over the globe. Iran, North Korea, etc. Heck, one complaint against Iraq having nuclear power was "They have so much oil! They don't need nuclear obviously, so therefore there is a sinister motive!" whilst "forgetting" that the coal reserves (and tar sands) exist in the USA as the second(?) largest world reserves of fossil fuels, yet THEY have had nuclear all the way back to the Texas Oil era.

Tristan @82
"In general, however, the energy balance equation is (rate of energy accumulation) = (rate of energy in) - (rate of energy out)."

Where and how can radiation be captured as radiation?
It's the matter in the ocean where energy is accumulating.

"An atmosphere which is transparent to visible light while capable of absorbing and re-emitting and/or reflecting infrared light reduces the rate of energy out while leaving the rate of energy in unchanged - thus leading to a net accumulation of energy, and hence increase in temperature."

The radiation can't be accumulating in the atmosphere. For radiation it's a system with multiple layers that differ in temperature. When adding layers, existing layers rise in temperature forced by the flux and preventing energy from accumulating.

"This increase in temperature in turn increases the rate of energy out; the temperature will thus increase to eventually reach a new equilibrium where the rate of output once again equals the rate of input."

Right, all in all the temperature of the effective layer has to go up. This layer is somewhere in Ta, and Ts does not change. That is what I said in the beginning.

Wow, cast aside the dogmatism of Atheist Fundamentalism and follow the evidence. Read the Merchants of Doubt and be surprised. Naomi Oreskes and Erik Conway have meticulously assembled the evidence and created a carefully reasoned case. We need to understand the reasons for opposition to climate change so that we can dismantle the objections. Clinging to outdated arguments about religion might satisfy some argumentative instinct but it is wholly ineffective when dealing with the problems of climate change.

wow@86

"Yup. It's made of two parts:

e*sigma*A*T1^4 leaving the hotter body, cooling it
e*sigma*A*T2^4 leaving the cooler body and warming the hotter body."

Yes, that is the long version of what I wrote.

"Because you're deliberately getting the bodies wrong.

T1 = earth's temperature
T2 = atmposphere's temperature."

No, radiation behaves the same for every layer to layer in the system. I started with this one in particular because it's the heat source.

"YOUR version has the earth warming up the Sun!
Which IS true, but if your complaints were genuine, would be FAR more ridiculous."

So, does the earth heat up the sun yes or no?

"This means that with the capacitor, you now have extra radiation coming in to the earth."

Extra radiation in to earth from what extra energy source?

"What happens when you increase the energy a body absorbs, hans?"

Indeed that's it, it's the energy the ocean body absorbs and that holds thermal heat that. So you see Ts is not strictly set by a radiation balance.

Hans, you seem hopelessly confused. Yes, the top of the atmosphere (where the radiation released is no longer reabsorbed) is the obvious place to apply a radiation balance between Earth and space.

Energy gets to that point from the Earth's surface by a combination of convection, conduction and radiation. Increasing opacity to IR does two things: 1: increases the height of the effective radiating layer, and so increasing the distance that convection and conduction have to work over; and 2: reduces the rate at which radiation can transfer energy from the ground to this layer.

So, the surface warms up - not because the atmosphere is absorbing all the energy, but because it's acting as an insulator reducing the rate at which the surface can shed energy.

An analogy: a lightbulb does not generate energy. It takes energy (in this case electricity) from outside, and converts it to heat which it radiates away as a combination of visible and infrared light. What do you think would happen to the temperature of the lightbulb filament if you were to wrap the bulb in reflective foil insulation?

wow@87

"But still earth surface will not get warmer.

Why not? The earth was getting the sun's radiation before and now it's getting the sun's radiation AND the atmosphere's radiation."

See 102.

"where you do think the energy above that from the sun comes from?", the answer to which is: the atmosphere."

The atmosphere is not generating energy. It holds thermal energy, so again this prevents us from looking at the system as a pure radiative balance.

daedalus2u@94

"Hans, If the quantity of heat radiated has to go up (because the Earth's surface is receiving more heat from the Sun plus re-radiated from the atmosphere), then the temperature of the Earth has to go up to radiate more heat in the same amount of time. The temperature of space is staying the same, the temperature of the Earth must go up."

So you say we have H sun in, and H sun + H atmosphere out. The radiative balance is then Hs = Hs + Ha, does that seem correct?

There is heat stored in the ocean/atmosphere as thermal energy that in time leaves as radiation. Radiation by itself cannot accumulate.

Neil B@96

"Hans, do you and similar realize that you are disagreeing with the basic concept that a planet with an atmosphere is warmer than it would be without one - that is the basic "greenhouse effect"

That is just what i'm pointing at. Look at the last part @74, and it's not just the atmosphere but even moere the ocean.

There's no need to worry about oil and natural gas running out, with peak oil already happened and peak gas probably already happened, and consumption of both skyrocketing as countries such as China and India industrialise to gain the 'good life' the West has enjoyed for so long because of the abundant cheap energy.

There's plenty of coal, enough for at least 150 years at present rates of consumption.

When the oil and gas runs out, we can just stick a lump of coal in the gas tanks of our cars, trucks and ships, and everything will be fine ...

By Wayne Robinson (not verified) on 02 Sep 2011 #permalink

@Tristan

We started with blankets which keep you warm. The blankets are thin and usually from cotton (not alu/silver).

You talk about reflective foil or insulation. You forget (suppressing) convection here.

A blanket keeps you warm because the hotter air is kept around the body closely. The hotter molecules are bounced back from the blanket. There is an amount of energy loss involving radiation here, but it is not the main reason for keeping you warm (if the temperature differences are not too great).
Our body can compensate for the radiation loss.

It is not the refection or insulation of a blanket that keeps you warm. Suppressing convection is more important here. The slowing of transport of heat is not caused by a change of "speed" of any photons involved. There is a mechanism at work here that translates molecular energy absorption (photons) to movement on macro scale. Photon exchanges are delayed that way by collisionless kinetics between molecules.

I like your posting because you show "Work" can be transported and (when it appears) energy is created in the form of heat/photons. It is a truly remarkable property of this universe that makes this transport of work/energy possible.

"You forget (suppressing) convection here."

But a single thin sheet will stop 100% of the convection coming from your body, Hannes.

Therefore why do you put a THICK blanket on in the winter when a thin sheet will stop 100% of the convection?

BECAUSE YOU KNOW YOU'RE TALKING BULLSHIT.

"No, radiation behaves the same for every layer to layer in the system. I started with this one in particular because it's the heat source."

You're talking bollocks again, hanny.

T1 is the temperature of the earth. T2 is the temperature of the atmosphere. Therefore, the cooler atmosphere is warming the ground.

"Indeed that's it, it's the energy the ocean body absorbs and that holds thermal heat that."

Hmmm. Another gish gallop.

Earlier you insisted they were the temperature of the sun and the earth.

Now you're saying that the ocean is T2.

Well, the ocean is cooler than the air, but you seem happy to consider that the ocean is warming the land here.

I guess you'll clutch any straw to pretend that the greenhouse effect doesn't exist, won't you.

"So you see Ts is not strictly set by a radiation balance."

It is for the earth system: there's nothing other than radiation.

""But still earth surface will not get warmer.

Why not? The earth was getting the sun's radiation before and now it's getting the sun's radiation AND the atmosphere's radiation."

See 102."

I did. Your statement "The radiation can't be accumulating in the atmosphere." in there is complete bullshit. It is accumulating in the atmosphere.

This is called "air temperature rising". And doesn't have anything to disprove my statement. You know you've got nothing so you're pretending to have answered when you have completely made stuff up.

"The atmosphere is not generating energy."

Yes it is. It's called "thermal radiation".

"It holds thermal energy,"

Yes, and it lets go of it through radiation, for example. And at the top, there's ONLY radiation to lose that thermal energy through.

"Radiation by itself cannot accumulate."

Now you're writing strawmen.

So sad, you lunatic.

""Hans, do you and similar realize that you are disagreeing with the basic concept that a planet with an atmosphere is warmer than it would be without one - that is the basic "greenhouse effect"

That is just what i'm pointing at."

We know.

That's why we believe you're a nut.

I'll use small words:

YOU ARE WRONG.

PS where's your proof that absolute zero has to reduce over time?

I don't really get how CO2 traps heat.

I get how an atmosphere traps heat-- heat trying to escape Earth to space is delayed, and scattered in random directions (some back at Earth). I don't really get how CO2 changes this. Is it somehow changing the ratio of heat radiated out vs back in, or is it just holding the heat longer before re-radiating?

By BlackFlag (not verified) on 10 Sep 2011 #permalink

sez blackflag: "I don't really get how CO2 traps heat.
"I get how an atmosphere traps heat-- heat trying to escape Earth to space is delayed, and scattered in random directions (some back at Earth). I don't really get how CO2 changes this. Is it somehow changing the ratio of heat radiated out vs back in, or is it just holding the heat longer before re-radiating?"
For an airless body like the Moon, things are pretty simple; sunlight in a wide range of different wavelengths falls on the body, the body heats up, the body radiates infrared-wavelength energy. Key point: Wide range of wavelengths on the input side; narrow range of wavelengths on the output side. Now, let's say you surround that airless body with something that absorbs energy in the infrared range a lot better than it absorbs energy in the visible range. If you do that, it's going to affect the output side a lot more than it does the input side, right? So with an infrared-specialized 'blanket' around your airless body, that airless body is going to get pretty much the same amount of energy input, but its energy output is going to drop. Same energy in, plus less energy out, equals the airless body keeping more energy to itself, hence that airless body will get hotter.
As it happens, CO2 is something that absorbs infrared-wavelength energy a lot better than it does visible-wavelength energy. So the more CO2 there is in Earth's atmosphere, the more infrared-wavelength energy gets trapped, hence the hotter Earth gets.
Does that clarify things, BlackFlag?

Perhaps the insulating properties of the CO2 atmosphere on Venus has something to do with the fact that the ATMOSPHERIC PRESSURE ON VENUS IS 93 TIMES HIGHER THAN ON EARTH? Venus is 30% closer to the sun, and has an albedo of 2/3 of earth so obviously it will absorb more solar radiation.

Anthropogenic global warming cannot be proven for a hundred different reasons. The earth is not a laboratory and there are no controls for the experiment.

I am a scientist and I know lots of other scientists who are just as skeptical. The science is not settled. Popular opinion on global warming seems fanatical. If we were truly objective, we would not quash opinions that we don't agree with but would instead try to present a scientific proof for our position. It cannot be done.

Wow:

> Wind generation is a random variable.

As is demand.

A lot of good that does if the correlation is zero.

See again: "since the supply more closely matches demand" and reconsider your assertions.

You should take your own advice.

reducing our "nameplate capacity" even further.

Wind generation always needs higher nameplate capacity than fuel-powered generators if it is going to replace them.

By Waiting for a … (not verified) on 12 Sep 2011 #permalink

> A lot of good that does if the correlation is zero.

It isn't. The correlation is quite good.

http://www.youtube.com/watch?v=llIbjC49Fjs

> You should take your own advice.

I did. You didn't.

> Wind generation always needs higher nameplate capacity than fuel-powered generators if it is going to replace them.

False.

Black flag, your answer is the statement you made that you say you've "understood".

Radiation is intercepted by CO2. When it's reradiated, it can go in any direction, including straight back. Without that GHG in the way, the radiation goes straight out.

False scientist Jeffrey: "Perhaps the insulating properties of the CO2 atmosphere on Venus has something to do with the fact that the ATMOSPHERIC PRESSURE ON VENUS IS 93 TIMES HIGHER THAN ON EARTH"

Nope.

The pressure cannot cause temperature to maintain. As any schoolboy scientist knows, when you increase the pressure on a body of gas, the volume decreases and that adiabatic contraction and expansion causes no change in temperature.

You are NOT a scientist and your assertion that other scientists are similarly "skeptical" is false.

> A lot of good that does if the correlation is zero.

It isn't. The correlation is quite good.

http://www.youtube.com/watch?v=llIbjC49Fjs

So the correlation is so good that storage schemes are necessary? Doesn't sound like quite good correlation to me. Asking other generators to vary their output doesn't sound like quite good correlation either.

> You should take your own advice.

I did. You didn't.

You didn't.

> Wind generation always needs higher nameplate capacity than fuel-powered generators if it is going to replace them.

False.

True.

By Waiting for a … (not verified) on 14 Sep 2011 #permalink

"So the correlation is so good that storage schemes are necessary?"

Is that what you think? Because I never said that. So apparently you think that has to be so.

"You didn't."

Yes I did. I even gave you a link.

Pity that you couldn't actually think, but rather used your "gut instinct" rather than your brain.

> > Wind generation always needs higher nameplate capacity than fuel-powered generators if it is going to replace them.

> False.

> True.

False.

Nuclear power? Ask San Diego. Or France. Even without catastrophic loss nuclear only gets 60% nameplate efficiency.

Pity you can't actually use the brain for what it's designed for.

"So the correlation is so good that storage schemes are necessary?"

Is that what you think? Because I never said that.

Your link said it. Do you normally use proof by irrelevant citation?

"You didn't."

Yes I did. I even gave you a link.

Yes I know, your proof by irrelevant citation.

Pity that you couldn't actually think, but rather used your "gut instinct" rather than your brain.

What a hypocrite.

> > Wind generation always needs higher nameplate capacity than fuel-powered generators if it is going to replace them.

> False.

> True.

False.

Nuclear power? Ask San Diego. Or France. Even without catastrophic loss nuclear only gets 60% nameplate efficiency.

So what do you think the average output of a wind turbine is compared with its nameplate? Nothing like 60%. And the reliable output is less than the average.

Pity you can't actually use the brain for what it's designed for.

I haven't got anything useful out of your brain yet.

By Waiting for a … (not verified) on 19 Sep 2011 #permalink

"Yes I know, your proof by irrelevant citation."

While you gave no citation and here are yet again asserting that the citation is irrelevant. Did you even look at the Greenman Video? He gives the names of the primary sources.

My problem is I gave you a citation that you didn't like.

"So what do you think the average output of a wind turbine is compared with its nameplate? Nothing like 60%."

I notice that you don't know what it is.

As I said, the concordance between demand and supply is higher.

And since wind is hugely over supplied, so what if we have to build twice as much nameplate power?

Ask Japan whose windfarms were still working to provide energy when their nuclear power station was FUBAR.

You're getting nothing from by brain because you don't like the facts, not because there are no facts at all.

To answer your question, there's a small wind farm on Shetland that has achieved a world record of 58% capacity over the course of a year. Offshore farms are pushing towards 40%.

And there are more efficiency gains to be made.

Oh, and Solar CHP is over 70% now.

Nuclear is barely managing 60%, if you ignore the 100% downtime of, for example, Three Mile Island, Chernobyl, Fukijama, and the other permanent nuclear accident sites.

just want to say. Space is not 'cold'. Not in the sense we mean it any way. There is no thermal radiation in space and planets do NOT radiate heat into space unless they have and are losing their atmosphere. Mercury's side gets cold because the heat is absorbed by the planet (and Mercury's day is very long so the dark side doesn't get hot while it radiates the heat inward.

I'm sure the author is aware of this but I saw no explanation of this in the article and using the term 'radiates' may be confusing to a layman because the way it's used colloquially refers to heat transfer via motion (convection). Indeed heat is all objects in vacuum SLOWLY lose heat via electromagnetic radiation (infra red for lower temps, visible light for medium to higher temps and ultraviolet for the highest energies)

But this process is VERY SLOW. In other words to put my point into perspective, if you were launched into space without a suit and survived you would feel comfortable temperature wise and would feel 'cold at all'. You would die from the lack of oxygen/ pressure and yes if you survived those too somehow lack of water/food or radiation before you 'froze'. Which would only happen after your body heat was 'radiated' away as infrared light.

" planets do NOT radiate heat into space unless they have and are losing their atmosphere"

Nope, 100% wrong there old boy.

This article is great! :)