pgleick | January 16, 2014 Figure 1: Monthly average precipitation showing the seasonality of precipitation in different parts of California, from the iconic California Water Atlas.
California has a “Mediterranean” climate, which means that each year it has a concentrated rainy season, followed by a long temperate and dry period. California’s rainy season typically runs from early October to late March, with very little precipitation outside of these months. (Figure 1 shows the average monthly rainfall for California.) It is now early 2014 and the rains have not come, for the third year in a row. While the …
pgleick | December 4, 2013Just to provide a little perspective, here are the latest data and a graph on atmospheric carbon dioxide, with information going back 800,000 years. Present day is on the far right ("You are here"). The data come from the atmospheric monitoring program of the Scripps Institution of Oceanography, La Jolla, California and can be found here.
I've also noted the approximate period when homo sapiens first appeared -- thought to be around 150,000 to 200,000 years ago. During all human existence, pre-industrial levels of CO2 never exceeded around 275 parts per million (ppm). They touched 400 ppm…
pgleick | December 3, 2013Water policy and water problems always seem to be someone else’s responsibility. Those farmers who use all the water; the guy down the street who lets his sprinklers run all over the sidewalk; the Central Valley cities that don’t even have water meters; the environmentalists who are demanding water for some inconsequential fish we can’t even eat; those swimming pool owners in hot Los Angeles.
The reality, of course, is that water problems belong to all of us. We all contribute in various ways through our choices of appliances, or diets, or Congressional representatives, or gardens. And every…
pgleick | November 7, 2013In the 20th century, water policy seemed easy: figure out another source of water to satisfy some projected demand, and find the money to build it. The money was almost always federal “pork barrel” funding for big water projects, or occasionally state bond financing. The vast number of dams built in the United States (see the figure) is an indication of how extensively this approach was used. But the leveling off of the curve below also shows that traditional dam construction can no longer be considered the only solution to our water problems. Moreover, most major water projects were designed…
pgleick | October 14, 2013Snow. Glaciers. Icecaps, River flows. All of these are vulnerable to climate change, especially rising temperature. This isn't just theory. It’s now observable fact.
Scientists worry about the growing threat of climate change because the global climate is tied to everything that society cares about: human and environmental health, food and industrial production, water availability, extreme events, and more. Figuring out how all these pieces tie together is difficult. And many of us, from scientists to the public to policy makers, have only a partial understanding of the true implications of…
pgleick | September 27, 2013The latest in a long series of science summaries on climate change from the Intergovernmental Panel on Climate Change (IPCC) has just been released. While the report has a massive amount of information in it, related to a wide range of geophysical implications of climate change, here are some of the key water-related findings for precipitation, evaporation, glaciers, ice mass, and more. While many other findings are reported that have hydrologic implications (such as all the findings related to temperature and warming), I have not usually included them here. Definitions of the confidence of…
pgleick | August 19, 2013
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…
pgleick | July 16, 2013
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…
pgleick | June 27, 2013For some time now, proponents of the controversial practice of hydraulic fracturing or “fracking” have claimed there was little or no evidence of real risk to groundwater. But as the classic saying goes: “the absence of evidence is not evidence of absence” of a problem. And the evidence that fracking can contaminate groundwater and drinking water wells is growing stronger with every new study.
As most people now know, fracking is a method for enhancing the production of natural gas (or oil, or geothermal energy wells). Fracking involves injecting fluids -- typically complex mixes of water and…
pgleick | June 20, 2013With Matthew Heberger. This is a version of a post from the blog "Pacific Institute Insights"
How much water is there in America’s rivers, and where is it? Perhaps unsurprisingly, people have little sense of how their local water resources compare in size to other water resources. “Is that a big river? A little river?”
One of us [Gleick] grew up along the Hudson River on the East Coast, and encountered rivers that seemed to be about the same size: the Susquehanna, the Delaware, the Potomac. Anyone living in the West working on water issues becomes more familiar with the Colorado, the…
pgleick | June 10, 2013There is a long history of conflicts over water – the Pacific Institute maintains an online, searchable chronology of such conflicts going back 5,000 years. There were dozens of new examples in 2012, in countries from Latin America to Africa to Asia. (A full update for 2012 has been posted.) Access to water and the control of water systems have been causes of conflict, weapons have been used during conflicts, and water systems have been the targets of conflict.
One especially disturbing example of a major conflict, with complicated but direct connections to water, has developed over the past…
pgleick | June 6, 2013One 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…
pgleick | June 2, 2013The Nile River – river of legend – is not just a river in Egypt. It is the lifeblood of 11 different African nations and the longest river in the world, extending over 6,500 kilometers long and draining a watershed of over 3 million square kilometers. The eleven nations that share the Nile are Egypt, Ethiopia, the Sudan and South Sudan, Kenya, Eritrea, the DR of Congo, Tanzania, Uganda, Burundi, and Rwanda.
The river is really two major rivers: the White Nile and the Blue Nile, which meet near Khartoum and become the mainstem of the Nile, flowing north to Egypt and the Mediterranean. The…
pgleick | May 10, 2013The planet has passed a disturbing landmark, a marker on a continuing highway to climate disruption. On May 9th, the NOAA and the Mauna Loa observatory reported that atmospheric CO2 levels touched 400 parts per million. Before humans started burning fossil fuels, they were around 280 parts per million.
Mauna Loa measurements of carbon dioxide. From http://keelingcurve.ucsd.edu/
The last time atmospheric CO2 was at 400 parts per million was during the ancient Pliocene Era, three to five million years ago, and humans didn’t exist.
Global average temperatures were 3 to 4 degrees C warmer…
pgleick | May 10, 2013The Colorado River, recently named America’s most endangered river, supports millions of people in the American Southwest and northwest Mexico and helps irrigate millions of acres of land. It is shared by seven states in the U.S. and Mexico, through a complex series of legal agreements and treaties.
Yet every drop of water on the river is accounted for, used, reused, and transpired away, and today, no water reaches the Colorado River delta in an average year. Quite simply, demands on the river exceed the river’s average supply, and this problem is projected to get worse as populations…
pgleick | May 9, 2013Municipalities are trying to find ways of dealing with the scourge of plastic bottles in their garbage, and with falling revenues from many sources. Plastic bottles have become a significant fraction of total garbage volume, and raise collection, handling, and landfill costs when they are not recycled. In 2011, according to NAPCOR (the National Association for PET Container Resources) 5.5 billion pounds of PET plastic bottles were available for recycling, but most of those bottles were not recycled.
One answer: impose a tax on bottled water.
Fewer than 1 in 3 of all PET bottles are recycled,…
pgleick | April 25, 2013The numbers are in for 2012, and they are shocking. The Beverage Marketing Corporation, which tracks sales and consumption of beverages, is reporting that sales of bottled water grew nearly 7 percent between 2011 and 2012, with consumption reaching a staggering 30.8 gallons per person. And since I (and some of you) consume almost zero bottled water every year, there are people out there drinking far more than the average.
Thirty-six years ago, this industry didn’t exist. Americans drank fewer than two gallons of bottled water per year, and almost all of that was in the form of water from big…
pgleick | April 22, 2013We live on solid ground, but the truth is, our planet is mostly covered in water. The famous writer Arthur C. Clarke noted this when he said, “How inappropriate to call this planet Earth when it is quite clearly Ocean.”
Today is Earth Day, when we celebrate the planet, and in particular the functioning ecosystem that supports all life, including our own. In recognition of Earth Day, here is a short piece about bottled water in the United States and most developed countries, with some basic facts that should help any readers still in doubt about the downsides of that industry.
The Money…
pgleick | April 10, 2013On 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…
pgleick | April 2, 2013Here are three iconic graphs (unfortunately, there are many, many more) showing just some of the clear observational evidence that we're changing the climate.
The first is the atmospheric concentration of carbon dioxide, measured at the Mauna Loa observatory in Hawaii. It shows the little ups and downs in concentration that varies with the seasons, but also the inexorable rise in this powerful greenhouse gas. There are now thousands of stations measuring these gases.
The second is the deviation from global average temperatures over the past 130 years. It also shows the natural variability (…