Friday, May 07, 2004

A number of recent reports have documented the rising temperature of the atmosphere and the effects that it is having on local climates.
New data 'confirms' global warming reports that scientists have found compelling new evidence for global warming, finally demolishing the argument of sceptics who have denied the phenomenon is real. New analysis of satellite data has revealed that temperatures in a critical part of the atmosphere are rising much faster than previously thought, strengthening the worldwide consensus that the earth is warming up. The findings, details of which are published today in the journal Nature, provide one of the final pieces of proof that global warming is taking place and that it is a human phenomenon.

At the same time A NASA satellite has captured record-breaking temperatures in Southern California, showing land that had baked to 70° Celsius just a day before the season's first wildfires ignited.

The Moderate Resolution Imaging Spectroradiometer (MODIS), which measures 36 bands of radiation from infrared to ultraviolet, snapped the image on Sunday when the Aqua satellite it flies on passed overhead. Aqua and its complementary satellite, Terra, image the entire planet every one to two days.

Temperatures in the air reached 40° C in Long Beach, nearly twice the city's average. The heat wave was exacerbated by a high pressure system falling north rather than south of the state, which brought in winds from deserts east of California.

In Arizona, the climate changes are changing the forests forever. Forget talk of global warming and speculation of what it might do in 50 years, or 100. Here and across the West, climate change already is happening. Temperatures are warmer, ocean levels are rising, the snowpack is dwindling and melting earlier, flowers bloom earlier, mountain glaciers are disappearing and a six-year drought is killing trees by the millions.

Outside Cody, Wyo., an entire forest has been killed by the drought and beetles. "It used to be a nice spruce forest," said Kurt Allen, a Forest Service entomologist. "It's gone now. You're not going to get those conditions back for 200 or 300 years. We're really not going to have what a lot of people would consider a forest."

In the southwest, global warming may be combining with a return to more natural climate conditions, with disastrous results. Scientists who study tree rings and ocean temperatures say, the development of the modern urbanized West — one of the biggest growth spurts in the nation's history — may have been based on a colossal miscalculation. That shift is shaking many assumptions about how the West is run. Arizona, California, Colorado, Nevada, New Mexico, Utah and Wyoming, the states that depend on the Colorado River, are preparing for the possibility of water shortages for the first time since the Hoover Dam was built in the 1930's to control the river's flow. The top water official of the Bush administration, Bennett W. Raley, said recently that the federal government might step in if the states could not decide among themselves how to cope with dwindling supplies, a threat that riled local officials but underscored the growing urgency.

Some of the biggest water worries are focused here on Lake Powell, the vast blue diamond of deep water that government engineers created in one of the driest and most remote areas of the country beginning in the 1950's. From its inception, Lake Powell, the nation's second-largest artificial lake, after Lake Mead in Nevada, was a powerful symbol across the West. Some saw it as a statement of human will and know-how, others of arrogance.

Powell, part of the Glen Canyon National Recreation Area, has lost nearly 60 percent of its water and is now about the size it was during the Watergate hearings in 1973, when it was still filling up. White cliffs 10 stories high, bleached by salts from the lake and stranded above the water, line its side canyons. Elsewhere, retreating waters have exposed mountains of sediment.

In the Pacific Northwest an unusually dry spring has melted snowpack in Washington's mountains and throughout the West at a troubling rate, causing heightened concern for drought conditions and forest fire danger, according to government officials and climate experts.

This week's snowpack measurements in the Cascades show little or no snow in areas that usually have several inches, hydrologists say. While it may give hikers a jump on the season, it does not bode well for water supplies, stream flows, fish, agriculture or forests, many say.

"It is extremely dry out there. The level of concern is very high," said Todd Myers, spokesman for the state Department of Natural Resources, charged with fighting fires on state and private lands.

Throughout the country the impact of global warming is already being felt. "We see an increase in overall precipitation of 5 to 10 percent over the past century, but the increase is especially prominent since the 1970s," said Tom Karl, director of the National Climatic Data Center in Ashville, N.C.

"But then if you look more closely at how precipitation is coming about, what we're seeing is that the increase is coming primarily through an increase in frequency and intensity of heavy and very heavy precipitation events," Karl said.

The increase in severe storms has been particularly dramatic in farm states _ Iowa, Missouri, Illinois, Nebraska, South Dakota and Wisconsin _ raising the potential for increased soil erosion and storm-water runoff from cropland.

"You hear a lot of stories from farmers and others that there has been a lot more damage _ 'This storm washed out my gullies' or 'This storm broke my terraces,' " said Craig Cox, executive director of the Soil and Water Conservation Society.

There has also been a marked increase in Atlantic hurricanes since the mid-1990s. From 1944 and 1996, there were an average of 9.8 hurricanes or tropical storms a year. But between 1995 and 2002, the average was 13.3. Last year, there were 16 named storms.

Some of the most dramatic effects have been on northern lakes. Water levels in Lake Michigan and Lake Huron, for example, started dropping in 1997 and have experienced their greatest decline in the shortest time since record-keeping began in 1860. Greater evaporation is believed to be the primary cause.

Lake Michigan levels are now 4 feet below normal and shipping has been severely hindered. Marinas have had to dredge to keep boats afloat and nuclear-power plants have had to extend their pipes to reach water for cooling.

In New England, Lake Champlain freezes over an average of eight days later in the winter than it did a century ago. Between 1815 and 1950, the lake failed to freeze over completely only six times; since 1950 it has failed to freeze more than 25 times.

Global warming is making itself felt in many great and small ways. Time is growing short to do anything about it.


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