The wrath of 2007: America's great drought

The irony will be lost on no-one. As George Bush, at the latest G8 summit, finally appeared to concede that there is such a thing as climate change and that the US will have to join the rest of the world in doing something about it, temperatures in the US are soaring and America is facing its worst summer drought since the Dust Bowl years of the Great Depression.

From the mountains and desert of the West, now into an eighth consecutive dry year, to the wheat farms of Alabama, where crops are failing because of rainfall levels 12 inches lower than usual, to the vast soupy expanse of Lake Okeechobee in southern Florida, which has become so dry it actually caught fire a couple of weeks ago, a continent is crying out for water.

In the south-east, usually a lush, humid region, it is the driest few months since records began in 1895. California and Nevada, where burgeoning population centres co-exist with an often harsh, barren landscape, have seen less rain over the past year than at any time since 1924. The Sierra Nevada range, which straddles the two states, received only 27 per cent of its usual snowfall in winter, with immediate knock-on effects on water supplies for the populations of Las Vegas and Los Angeles.

For the moment there will be no obvious signs of change as the farmers are well protected by subsidies and emergency funds, and the only visible sign that something might be amiss are the hosepipe bans being imposed on eastern cities.

But the long term implications should escape nobody.

Climatologists see a growing volatility in the south-east's weather - today's drought coming close on the heels of devastating hurricanes two to three years ago. In the West, meanwhile, a growing body of scientific evidence suggests a movement towards a state of perpetual drought by the middle of this century. "The 1930s drought lasted less than a decade. This is something that could remain for 100 years," said Richard Seager a climatologist at Columbia University and lead researcher of a report published recently by the government's National Oceanic and Atmospheric Administration (NOAA).

While some of this year's dry weather is cyclical - California actually had an unusually wet year last year, so many of the state's farmers still have plenty of water for their crops - some of it portends more permanent changes. In Arizona, the tall mountains in the southern Sonoran desert known as "sky islands" because they have been welcome refuges from the desert heat for millennia, have already shown unmistakable signs of change.

Predatory insects have started ravaging trees already weakened by record temperatures and fires over the past few years. Animal species such as frogs and red squirrels have been forced to move ever higher up the mountains in search of cooler temperatures, and are in danger of dying out altogether. Mount Lemmon, which rises above the city of Tucson, boasts the southernmost ski resort in the US, but has barely attracted any snow these past few years.

At the recent G8 Summit, George Bush continued to act as if this is a problem that can be sorted some way down the line by technological advances, implying that our lifestyles can stay the same and technology will take care of everything else.

But, just as droughts are starting to hit Australia, there is every indication that the US too is starting to feel climate change's effects.

"A lot of people think climate change and the ecological repercussions are 50 years away," Thomas Swetnam, an environmental scientist at the University of Arizona in Tucson, told The New York Times a few months ago. "But it's happening now in the West. The data is telling us that we are in the middle of one of the first big indicators of climate change impacts in the continental United States." Across the West, farmers and city water consumers are locked in a perennial battle over water rights - one that the cities are slowly winning. Down the line, though, there are serious questions about how to keep showers and lawn sprinklers going in the retirement communities of Nevada and Arizona. Lake Powell, the reservoir on the upper Colorado River that helps provide water across a vast expanse of the West, has been less than half full for years, with little prospect of filling up in the foreseeable future.

According to the NOAA's recent report, the West can expect 10-20 per cent less rainfall by mid-century, which will increase air pollution in the cities, kill off trees and water-retaining giant cactus plants and shrink the available water supply by as much as 25 per cent.

Georgian farmers are already saying that they may lose as many as two thirds of the state's celebrated peaches this year, thanks to the driest spring on record followed by a devastating frost. So the effects of climate change are beginning to be felt now, and this is obviously not a problem that can be passed to future generations or made to wait for technological advances.

When George Bush came into office, he came in denying that such a thing as climate change existed. The reality is now making itself felt all across America.

Like anything climatical, the changes will make themselves known subtly at first. But, eventually scientists say, what we regard as unusually dry periods will reveal themselves to be the new norm.

Scientists in Australia recently questioned the use of the word "drought" to describe what was taking place there, as the word "drought" describes an unusual period of water shortage that is eventually naturally corrected. That, is not they say, what we are witnessing.

The early 21st century drought is the most severe in terms of flow deficit in more than a century. The current drought also has produced the lowest flow period in the record, with an average of only 5.4 MAF for 2001-2003. In contrast, the drought of the Dust Bowl years between 1930 and 1937 produced an average of 10.2 MAF. The predicted inflow into Lake Powell for 2004 is 49% of the long-term average (5.6 MAF), which indicates that the early 21st century drought is on-going.

According to the U.S. Geological Survey, the latest drought is the worst to occur in North America in the last five hundred years.

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Tags: water shortage, global warming, climate change, America, United States, drought, Bush, Republicans