population

Populations around the world face many severe water challenges, from scarcity to contamination, from political or violent conflict to economic disruption. As populations and economies grow, peak water pressures on existing renewable water resources also tend to grow up to the point that natural scarcity begins to constrain the options of water planners and managers. At this point, the effects of natural fluctuations in water availability in the form of extreme weather events become even more potentially disruptive than normal. In particular, droughts begin to bite deeply into human well-being…
(Photo: Peter Gleick 2008) The recent severe drought in the Western United States -- and California in particular -- has shined a spotlight on a range of water-management practices that are outdated, unsustainable, or inappropriate for a modern 21st century water system. Unless these bad practices are fixed, no amount of rain will be enough to set things right. Just as bad, talking about many of these bad practices has been taboo for fear of igniting even more water conflict, but the risks of water conflicts here and around the world are already on the rise and no strategy that can reduce…
Over the past three years (and indeed, for 10 of the past 14 years) California has experienced a particularly deep drought. How bad is the drought? Is it the worst in the instrumental record? The worst in over a century? The worst in 1200 years? The worst “ever”? And why has it been so bad? There is no single definition of “drought.” Drought, most simply defined, is the mismatch between (1) the amounts of water nature provides and (2) the amounts of water that humans and the environment demand. As the National Drought Mitigation Center puts it: “In the most general sense, drought originates…
  Dropping water levels in Lake Mead, behind Hoover Dam. (Source: Peter Gleick 2013) It is no surprise, of course, that the western United States is dry. The entire history of the West can be told (and has been, in great books like Cadillac Desert [Reisner] and Rivers of Empire [Worster] and The Great Thirst [Hundley]) in large part through the story of the hydrology of the West, the role of the federal and state governments in developing water infrastructure, the evidence of droughts and floods on the land, and the politics of water allocations and use. But the story of water in the West…
Life has been growing on Earth for about 4 billion years, and during that time there have been a handful of mass extinctions that have wiped out a large percentage of complex lifeforms.  Asteroid impact, volcanic eruption, climate change, anoxia, and poison have dispatched untold numbers of once-successful species to total oblivion or a few lucky fossils.  Species also die off regularly for much less spectacular reasons, and altogether about 98% of documented species no longer exist. Cry me a river, you say, without all that death there would have been no gap for vertebrates, for mammals, for…
The evidence from real-world observations, sophisticated computer models, and research in hundreds of different fields continues to pile up: human-caused climate change is already occurring and will continue to get worse and worse as greenhouse-gas concentrations continue to rise. Because the climate is connected to every major geophysical, chemical, and biological system on the planet, it should not be surprising that we are learning more and more about the potential implications of these changes for a remarkably wide range of things. And while it is certainly possible – even likely – that…
One day, sometime around the middle of this century, during the lifetime of people now alive, the population of the planet will be smaller than it was the day before. Global population growth is slowing, will level off, and one remarkable day, decline. This day will mark the dividing line – the definitive transition – between a world dominated by the concept of exponential, inexorable growth to one that has the opportunity to come to grips with true long-term global sustainability. Ever since the dawn of humanity, the population of the planet has been growing (ok, some quibblers may point out…
On April 2nd, I posted three iconic graphs showing some of the clear observational evidence that we’re changing the climate. That post produced a substantial, and largely thoughtful response, and a request for more information and data along these lines. Here are three more, along with a bonus fourth, all with a theme of exponential growth – the powerful force that is behind much of the concern about climate change and many other environmental and social challenges. Figures like these are increasingly called “hockey stick” curves, after the work of Professor Michael Mann and others in the…
Chances are you already have a strong opinion on this subject.  There's a great deal of noise, mostly but not wholly on the American right about the dangers of fertility decline.  Jonathan Last's book  _What To Expect When No One is Expecting_ and Ross Douthat's recent lament about American women's TFR (total fertility rate - the reason men aren't mentioned is that men don't count in fertility calculations) is down to 1.87 children.  Both writers predict fairly dire outcomes - economic stagnation a la Japan, a benefits crisis as insufficient new workers arrive.  Moreover, for Douthat and…
I read an interesting article today on how eating insects may save the world. The rationale: eating insects are not only nutritious (high in protein and fat), but would also help to save the Earth's resources as the human population continues to expand. According to Aaron T. Dossey, a biochemist, entomologist, and founder and owner of All Things Bugs, humans consume ~40% of potential terrestrial productivity and livestock currently takes up ~30% of the Earth's land (pasture and growing feed). With the growing population of humans, food consumption will necessarily increase. He sees insects…
Note: I wrote a slightly different piece under this title on ye olde blogge back in August, but given the emphasis on discussion of contraception going on, I thought it was worth reiterating and mulling over further. When your specialty as a foster family is taking large sibling groups, you hear a lot of stuff you'd rather not. The typical comment involves forced sterilization, and it is hard sometimes not to have a little sympathy. Of the kids we've taken or been called about, we've had three groups of five and three of four, and almost all have involved very young mothers, sometimes with…
One of our families favorite things to do is check out old cemetaries - my kids love to read gravestones and talk about the stories that came behind them. I love cemetaries - I find them comforting in an odd way, although I'm not fully sure I can explain why, and I'm glad that my children have the same passion for historical records and also the same pleasure in knowing something about lives before ours. Walking in old graveyards is also always a reminder of how fortunate I am. Most graveyards have a "children's" section, or family stones record the brief and incredibly short lives of…
On the 31st of October we will officially reach 7 billion people on the earth. Over the next week or two we'll be talking a lot about population issues, and I wanted to start by doing a light revision of an article I wrote some years ago about a concept a lot of people don't grasp very well - the idea of demographic transition and what it means. The term "Demographic Transition" describes the movement of human populations from higher initial birth rates to a stabilzed lower one, and seems to be a general feature of most societies over the last several hundred years. Initially, birth rates…
From Yale Environment 360, more questions about future UN population projections: For now, we can indeed be highly confident that world population will top 7 billion by the end of this year. We're close to that number already and currently adding about 216,000 people per day. But the United Nations "medium variant" population projection, the gold standard for expert expectation of the demographic future, takes a long leap of faith: It assumes no demographic influence from the coming environmental changes that could leave us living on what NASA climatologist James Hansen has dubbed "a…
On Casaubon's Book, Sharon Astyk asks if we can stomach a new kind of cuisine— in case, you know, a massive volcanic eruption wipes out all our staple grains. Instead of wheat, corn and rice, "we probably would begin getting comfortable with acorn pancakes and turnip stew with taro dumplings." But Sharon says that even barring catastrophe, "something *is* happening, something disastrous. The wheat is being grown often on dry prairie soils that should never be plowed at all. The corn and soybeans are being grown continuously in the midwest at a high cost to both topsoil and the ability of…
There are ten children in my house, but six of them are phantoms. No, we haven't gotten a foster placement or heard anything new since the two weeks in August when we were asked to take two separate groups of five kids each. Both of those placements fell through, and there has been nothing since, which is sort of the problem. I have little patience with being expectant, whether pregnant or waiting for a foster placement, and the six (this is a totally arbitrary number that I'm using only because it represents the number of van seats, and thus the maximum placement we could take) "ghost…
Fill in the blanks: It is customary in the popular media and in many journal articles to cite a projected _________ figure as if it were a given, a figure so certain that it could virtually be used for long-range planning purposes. But we must carefully examine the assumptions behind such projections. And forecasts that ________ is going to level off or decline this century have been based on the assumption that the developing world will necessarily follow the path of the industrialized world. That is far from a sure bet. That comes from an essay at Yale's e360. Given that you're reading a…
Hi Folks - Back from the wedding and shivaree, and catching up...slowly. Tired and have much farm stuff to catch up on as well, so bear with me one more day. In the meantime, Fred Pearce has a great essay in Nature on what's wrong with the UN population revisions that anticipate 10+billion by the end of the century. As you'll remember, I'm pretty dubious about the underlying assumptions of the model as well - it doesn't have anything to do with the real constraints we're facing. The Pearce article is well worth a read, even though I don't agree with all of his assumptions about the…
A recent email I received was pretty typical - I won't quote it here because the person meant well, but the sum up was this - they laud my decision to adopt, argue that I should have done it earlier, and point out that adoption is the solution to the population crisis. People who want children should just adopt, rather than giving birth. In the spirit of my discussion of the new suggestion that the world will hit 10 billion, I thought this was a good subject to take up. Now as usual, I'm not going to recite my discussion of why I have four biological kids - and I'm not going to argue that…
The fact that the mid-range projections for world population rose by nearly a billion people this week should have garnered a lot more attention than it did. The UN offers biennial updates of its world population estimates, and for the last few years, the mid-range (ie, the most likely scenario) has suggested that the world will peak around 9.2 billion people near the middle of this century, and then slowly begin to decline. The 2010 estimate, however, found that the decline is no longer considered likely, and that by 2100, the world may have as many as 10.1 billion people. This raises a…