Commercial fishermen along the Southwest Florida coast are reporting a massive dead zone that is almost devoid of marine life in an area of the Gulf of Mexico traditionally known as a rich fishing ground. [...] fishermen with decades on the water say they've often seen red tide but they've never seen anything like this — it doesn't have a foul smell, it isn't red tide and it isn't oil. They describe it as viscous and slimy water with what looks like spider webs in it. [...] And now fishermen from Fort Myers Beach to the Keys ... said there have been bigger fish kills that aren't making it onto government reports.

The largest, many say, occurred late last year about 30 miles off Tampa Bay. It had shrimpers pulling up netloads of dead and decaying fish off the bottom, they said.

Some shrimpers based on Fort Myers Beach worry that a recent and unexplained slew of flesh-destroying infections they've seen among their number may be related to problems in the Gulf.

The infection is diagnosed as cellulitis in three of their medical reports. They say it begins with a blister on the skin but swells to a large nodule before it erupts and then spreads. It can only be treated with stout antibiotics. [...] Grant Erickson, 48, owner of Fort Myers' Erickson and Jensen Seafood, has a fleet of eight boats. He said he, too, hadn't seen the likes of these infections in the business that his family has been in for a half-century.

The Earth's magnetic poles might be starting to flip say researchers who have seen strange anomalies in our planet's magnetic field.

The magnetic field is created by the flow of molten iron inside the Earth's core. These circulation patterns are affected by the planet's rotation, so the field normally aligns with the Earth's axis - forming the north and south poles.

But the way minerals are aligned in ancient rock shows that the planet's magnetic dipole occasionally disappears altogether, leaving a much more complicated field with many poles all over the planet. When the dipole comes back into force, the north and south poles can swap places.

The last reversal happened about 780,000 years ago, over a period of several thousand years. Now Gauthier Hulot from the Institute of Earth Sciences in Paris and his colleagues think they have spotted early signs of another reversal.

South African anomaly

The anomalies have already reduced the overall strength of the planet's magnetic field by about 10 per cent. If they continue to grow at the same rate, the Earth's dipole will disappear within just two millennia.

But Ørsted is the first satellite to take a snapshot of the Earth's magnetic field for 20 years, and such scant data makes it difficult to predict future shifts.

"We can't really tell what will happen," says Hulot. "But we speculate that we're in an unusual situation that might be related to a reversal."

Journal reference: Nature (vol 416, p 620)

Astronomers have detected signs of a supernova explosion and tied it to the output of even higher-energy radiation known as a gamma-ray burst. The discovery adds to evidence that suggests supernovae and gamma-ray bursts sometimes are linked.

Gamma-ray bursts, or GRBs as they are called, have remained largely mysterious since their discovery in the 1960s. They pack the electromagnetic output of many galaxies into a single flash that lasts seconds or less. If one occurred nearby, it could destroy life on Earth

The new study, which will be reported in the April 4 issue of the journal Nature, found hot gas containing elements such as magnesium, silicon and sulfur, which are common products of a supernova, an explosion that marks the end of a massive star's life. The gas was streaming outward from a known GRB site at one-tenth the speed of light.

James Reeves of the University of Leicester, UK, led the study. Reeves explained what he figures is going on, a scenario that other researchers have described previously:

As massive star nears the end of its life, it casts huge amounts of material into space. In a grand finale, a bubble of hot gas explodes outward. Material that's left behind is thought to collapse into a black hole. The whole mess rotates, and two jets of gamma rays and other emissions are shot out in opposite directions, along the axis of rotation.

"Eventually, the hot fireball from the [supernova] burst catches up with the dense material [previously] ejected from the massive progenitor star," Reeves said. "This material is heated up and produces the X-ray emission from those elements that we see in our observations."

Importantly, Reeves and his colleagues did not detect iron, as might have been suspected in the wake of a supernova. This is likely because there had not been enough time for iron to form via radioactive decay, he said, implying that the time between the supernova and the GRB is very short.

"The new results strengthen the link between GRBs and supernovae, and favor models where the GRB occurs within a few days after the supernova," said Herman Marshall of MIT, in writing an analysis of the paper for the journal.

The findings are supported, Marshall said, by other recent detections of iron in the X-ray afterglows of gamma-ray bursts. These earlier observations, made by NASA's Chandra X-ray Observatory and the XMM-Newton, were not conclusive on their own.

The new study used data collected by the Italian-run BeppoSAX satellite and the European Space Agency's XMM-Newton.

Robert Watson, one of the world's leading climate scientists, has been ousted from his job as chairman of the UN's Intergovernmental Panel on Climate Change. This followed the withdrawal of support by the US government, apparently at the behest of the oil company ExxonMobil, which had lobbied against him.

The frequently outspoken Watson is replaced by one of his vice-chairmen, a respected Indian science administrator, economist and former railway engineer, Rajendra Pachauri.

The vote, which took place at an IPCC meeting in Geneva on Friday, came as a surprise after there appeared strong backing for a British proposal for the two men to share the chair.

Colleagues say Pachauri is no patsy. If anything, coming from the developing world, his views are stronger than Watson's on the rich countries' responsibility for reducing the emissions of the greenhouse gases that cause global warming.

And his technical knowledge of how industry could clean up its act is certainly stronger than Watson's. He has been running the Tata Energy Research Institute, which works on this very topic, for the past 20 years. But he will be the first non-atmospheric chemist to take the job

Industry links

Pachauri also has a reputation for being less abrasive towards industry than Watson. He has been profiled on the web sites of both Ford and Unilever. However his main attribute for the US was not being Robert Watson.

Watson was born in Britain, but has worked in the US for many years. He has spoken very strongly about the need for action to combat global warming, enraging global warming sceptics.

Watson had spent three years as chair of the IPCC and had, until news of the US opposition emerged, been expected to achieve a second term without trouble - as did his predecessor the Swedish climate scientist Bert Bolin.

But he fell victim to an alliance between the US - which may have threatened to drop funding for the IPCC if he stayed on - and many developing world countries, who took the chance to appoint "one of their own" to the world's top climate science job. The vote, among government representatives, was 57 for Pachauri and 49 for Watson.

Few expect the scientific message of the IPCC to change as a result of the coup. But there are fears that it will be easier for the US, the world's largest polluter, to ignore the IPCC's message when it comes from an Indian.

And there are wider fears that, for the first time, the workings of the IPCC have become politicised. Once tainted, its strength as the "voice of science" on one of the great environmental issues of the day may never be quite the same again.

Kate Hampton, international climate co-ordinator for Friends of the Earth said: "The fossil fuel industry and the US government will be celebrating their success in kicking out Bob Watson, an experienced scientist who understood that urgent action is needed to tackle global climate change. The Bush administration and its friends would rather shoot the messenger than listen to the message."

The punishing drought covering nearly a third of the United States has the potential to cause severe water shortages along the East Coast this summer, create one of the worst wildfire seasons in the Southwest and hinder the nation's fragile economic recovery, drought experts say.

Although April showers have brought a deceptively green veneer to some drought-stricken regions, the National Oceanic and Atmospheric Administration warns that rainfall deficits are so severe in some parts of the country that it would take months of above-normal precipitation to end the drought.

Most of the attention has focused on the Northeast, where an unusually persistent high-pressure system produced record warm winter temperatures and kept away the winter storms that normally fill reservoirs, raise stream flows and moisten the soil. There were almost no major snowstorms this winter in the East, except for a big one that hit Buffalo, N.Y., in December.

The Northeast experienced its second driest September-to-February period in 107 years, and New Jersey, Delaware and Maryland experienced their driest February on record. New Hampshire, under a drought warning since last September, recorded its driest winter in the last 47 years and its warmest winter in 143 years. Maine matched its driest year in more than a century of record-keeping. And rain and snowfall in Washington, D.C., was 70 percent below normal for the September-to-February period, a 13-inch deficit.

Hundreds of private wells across Maine have dried up, keeping well-drilling companies working overtime. Water managers throughout the region have reported stream flows and reservoir levels of near-record lows.

The three reservoirs in the Catskill Mountains that send drinking water to New York City and Philadelphia hold only about half as much water as normal for this time of year. Baltimore's three reservoirs are normally 95 percent full this time of year, but are currently only about 60 percent full. The city is supplementing its water supply by withdrawing 140 million gallons of water a day from the Susquehanna River. Usually it doesn't take any water directly from the river.

The severe drought has led to widespread restrictions on lawn watering, car washing and the filling of swimming pools. Restaurants have been asked not to serve water except on request and homeowners have been asked to use brooms instead of hoses to wash driveways and sidewalks.

Violations of water restrictions in New York City, which has declared a drought emergency, are punishable by fines up to $1,000. The New Jersey Department of Environmental Protection, meanwhile, has ordered local water utilities to plug their leaks.

"I don't think we've had conditions like this in the Northeast for 30 to 40 years,'' said Bill Lauer, a water engineer with the American Water Works Association, which represents public and private water suppliers. "It's still early. The full impact isn't going to be felt until later this summer.''

Environmentalists are concerned that the vernal pools that usually form in the Northeast in spring and then dry up in the summer's heat are not appearing or are reduced in size this year. Salamanders and other amphibians rely on the pools for mating and egg-laying.

The greatest fear is that there will be severe water shortages by summer in some of the hardest-hit states. Meteorologists and hydrologists predict that sparse rainfall this spring, coupled with warm weather, could result in conditions comparable to the East Coast drought of 1963-1965, which drained many reservoirs and private wells.

Meanwhile, forecasters are watching an El Nino weather pattern developing over the Pacific. The last four El Ninos have resulted in drier-than-normal conditions in April through June in New England.

So far, forecasts predict a warmer-than-normal summer in much of the Mid-Atlantic region. Precipitation forecasts give an equal probability to greater-than-normal and lower-than-normal rainfall through July for much of the East Coast, except for Georgia, South Carolina and western North Carolina, where lower-than-normal rainfall is more likely.

While recent rainfall deficits have been the most extreme in the Mid-Atlantic, the Southeast and Maine have been in a dry spell since 1998.

There is only a 5 percent to 10 percent chance that rainfall between now and July will end drought conditions on the East Coast, said Richard Tinker, a drought specialist with NOAA's Climate Prediction Center.

"We're not in a lot of deep trouble yet, but what concerns everybody is that if you get dry periods during the summer, they will have an even greater effect than they would otherwise because you don't have reserves to fall back on,'' Tinker said.

The outlook isn't much better in a drought-plagued swath of the West extending from Montana south through Wyoming and Colorado, and across New Mexico, Arizona, and Southern Nevada to Southern California.

Southern California just had its driest winter ever. The National Weather Service recorded only 1.4 inches of rain at Lindbergh Field in San Diego from December through March, breaking a winter record that had stood since 1850.

In the West, where prolonged drought is more common than in the Northeast, the chief worry is that conditions will lead to a potentially devastating wildfire season. Colorado Gov. Bill Owens has asked the federal government to declare a drought emergency covering his entire state. With mountain snowpack at only 27 percent of normal, Owens said the state is facing some of the driest conditions in memory.

Some climatologists believe that frequent warm winters over the past decade may be increasing drought in the West by raising average temperatures in the upper reaches of mountains, thus reducing snowpack and the spring runoff that communities in the mountain states and desert Southwest rely on for water.

On the East Coast, which normally gets three to four times the rainfall of the arid West and Southwest, reservoirs are generally smaller and less able to accommodate prolonged drought.

"It's sort of human nature that if extreme events don't happen as frequently, memory slips and those types of communities are less well prepared for the future,'' said Robert Harriss (CQ), director of the environmental and societal impacts group at the National Center for Atmospheric Research.

"I think what we're going to see, that as water restrictions continue to become more widespread this summer, it's going to impact our economy in every single sector from building construction to food prices, and because water is linked tightly to electricity, it's going to potentially affect electricity prices.''

The drought could wind up increasing the consumer price index, the nation's inflation barometer, Harriss said.

Significant population growth in recent decades and widespread urban sprawl have magnified the effects of drought by increasing demand for water, experts say.

"A lot of communities along the East Coast and in the Southwest seriously have to take a step back and look at how much they can continue to grow,'' said Mark Svoboda, a climatologist at the National Drought Mitigation Center at the University of Nebraska.

"They are taxing the system in some cases to the point where it doesn't take a drought of the magnitude of (those in) the '60s or the '30s or the '50s, depending upon where you are, to have major impacts because you are a lot more vulnerable.''

On the Net:

National Drought Mitigation Center - http://drought.unl.edu/ndmc/

PADUCAH, Kentucky (CNN) -- Tornadoes swept through southeastern Missouri, Illinois, western Kentucky and Maryland on Sunday, killing at least six people and damaging dozens of buildings, authorities said.

The twister system in the Midwest killed three people in three states early Sunday, while three others died in Maryland when a tornado touched down there Sunday night.

The pattern of damage in the Midwest led authorities to suspect that a single tornado -- not several -- caused most of the destruction early Sunday, said Jim Packett, a meteorologist with the National Weather Service in Paducah. Packett said that authorities will not definitively know which twister or twisters caused the damage for several days.

"We may end up with a tornado path length of over 100 miles, if it all pans out like we think," said Packett, noting there was damage in at least 10 Midwest counties.

An F3 tornado -- about 4 miles long and packing winds up to 180 miles an hour, average strength for such a storm -- touched down around 12:40 a.m. (1:40 a.m. EDT) about 5 miles southwest of Marble Hill, Missouri, Packett said.

The twister killed a 12-year-old boy in Marble Hill, about 90 miles south of St. Louis, and injured 16 others, a sheriff's dispatcher said.

In Dongola, Illinois, about 30 miles south of Carbondale, the tornado killed an elderly woman outside her mobile home, a sheriff's dispatcher said. Six others were injured and "a number" of homes and businesses were damaged, said Packett.

The storm caused damage in Illinois' Pope and Johnson counties as it made its way east and to the state's southern tip, said Packett. It then crossed the Ohio River into western Kentucky, causing damage in Livingston, Crittenden and Hopkins counties.

The twister blew 46 full freight cars off the railroad tracks in Providence before hitting Caldwell County, around Princeton, where 29 people were taken to the hospital and a number of homes and mobile homes were destroyed, according to Packett.

Officials in Breckinridge County, Kentucky, said a man was killed outside his mobile home on the southwest side of Irvington, about 40 miles southwest of Louisville. The storm also damaged a subdivision on the south side of town.

"There was a pretty good-size motor home turned upside down on a boat," said Breckinridge Sheriff's Deputy Sandra Wood.

'It was a roar, and then I saw the funnel'

The tornado Sunday night in southern Maryland killed three people and injured dozens of others. The twister slammed into businesses and houses, forcing people into shelters, according to government and weather officials.

The tornado went through a 12-mile area, said Nina Voehl of the Charles County Sheriff's Office, starting in the small town of La Plata and going east through what is largely a rural area with a lot of farmland. After passing through the town of Benedict, the system plowed across the Patuxent River and entered Calvert County. The weather system produced golf-ball sized hail all along the way.

Two people were killed in La Plata in Charles County, about 25 miles south of Washington, Charles County officials said. One was in a residence and the other was in a vehicle at the corner of Routes 301 and 6. Another was killed in Hallowing Point near Prince Frederick in next-door Calvert County, said Don Hall, the county's emergency management director.

Charles County Commissioner Murray Levy said he saw the tornado touch down not far from his home, just outside La Plata.

"I'd never heard anything like that in my life," he said. "My wife and I were on the back porch and she said, 'Do you hear that?' And it was a roar, and then I saw the funnel, and then it touched down just to the east of our house."

About 12 people from Charles County were taken to trauma centers in the region and at least 81 people from the county were sent to area hospitals for treatment, Voehl said.

At least 35 people were staying at a shelter set up at local high school in Charles County and 11 families in Calvert County have been put up by the Red Cross in hotels, Maryland officials said.

Storm system knocks down buildings in Virginia

Strong winds and hefty hail battered Bedford County, Virginia, on Sunday afternoon, damaging at least 50 homes but causing no major injuries, officials said.

The system knocked down a number of buildings in Bedford, a city of 70,000 about 20 miles east of Roanoke, said county Sheriff Mike Brown.

Authorities shut down the downtown area and a number of streets "just in case anybody had looting on their mind," Brown said.

National Weather Service meteorologist Jim Hudgins said the storm, which moved through the area around 4:30 p.m., could have been a tornado or just strong winds. The Virginia storms did belong to a different band of storms than the one that caused a tornado in Maryland, he said.

Most of the damage happened along Route 460, a major four-lane highway linking Roanoke and Lynchburg that runs through the center of town, Brown said. The Red Cross was on the scene and the local Wal-Mart was serving food, he said.

Most supernovae occur when large stars run out of fuel and then collapse under their own weight. As atoms in the star are squeezed together, they rebound outwards, blowing off energy in a dazzling and dangerous display lasting several weeks.

But this one is different. Called HR 8210, it is a humble white dwarf, a star that has run out of fuel and should be too small to produce a supernova. But it may not stay that way. First, it is not alone, but is orbiting a companion star in a typical binary system. And it is 1.15 times the mass of our Sun, which for a white dwarf is a whopper.

The system was first logged in 1993 but little attention was paid to it. Then when Harvard student Karin Sandstrom investigated HR 8210 for a college paper this year, she discovered that it is only just shy of the Chandrasekar limit - the mass at which it would be big enough to go supernova. That makes it the best and by far the closest supernova candidate discovered so far.

The crunch will come when HR 8210's companion begins to run out of fuel. As it expands to form a red giant star, its outer layers will be dumped onto HR 8210, pushing it over the Chandrasekar limit. "Our initial idea was that this might happen very soon," says Sandstrom's supervisor Dave Latham.

But do not panic yet. "Very soon" could mean hundreds of millions of years in the future. And that is just as well, because we are only 150 light years away from HR 8210 at present - well short of the 160 to 200 light years thought to be the minimum safe distance from a supernova. If it did let fly, the high-energy electromagnetic radiation and cosmic rays it released would destroy Earth's ozone layer within minutes, giving life little chance of survival.

This would not be the first time a supernova has changed the course of life on Earth. In 2001, Jesus Maiz-Apellaniz and colleagues from the Space Telescope Science Institute in Baltimore, Maryland, found a "smoking gun" supernova remnant, in the group of stars known as the Scorpius- Centaurus association.

The timing of the supernova corresponds to an otherwise mysterious deposit of heavy isotopes in deep Earth cores and to a mass marine extinction two million years ago. At the time, Scorpius-Centaurus was around twice as far away from Earth as HR 8210 is now.

Fortunately, it will take time for HR 8210 to accumulate the mass it needs. Preliminary calculations by Rosanne di Stefano at the Harvard-Smithsonian Center suggest this may take hundreds of millions of years. By that time it will be much further away, she says, though she still needs to confirm exactly how far. "I want to be sure I'm right."

But will similar stars threaten us before then? "The fact that there's such a system so close to us suggests maybe these objects are not so rare," says Latham.

A solar flare has silenced Japan's first Mars probe, cutting communications with Earth. Japanese officials say the spacecraft's computers can be reconfigured to fix the problem - but this may take six months.

Communications with Nozomi were severed on 21 April, but this was only revealed on Friday by Japan's Education Ministry, which oversees the country's space program.

Sudden explosions on the surface of the Sun release electromagnetic energy and energetic particles. These solar flares can cause disruption to electronics systems on board satellites and even some electronic and power systems on Earth.

Yoshihisa Nemoto of Education Ministry said the computer systems aboard Nozomi are still intact and engineers will work to repair them. Nemoto added that the spacecraft remains on course to reach Mars in December 2003.

Nozomi was launched in July 1998 and was supposed to reach Mars a year later. An orbit correction manoeuvre in December 1998 used up too much fuel, however, throwing the probe off course and delaying its arrival by four years.

The spacecraft cost 11 billion yen ($88m) and will study the Mars's upper atmosphere and ionosphere, focusing on the effect of solar wind. It will also return images to Earth. There are 14 different instruments aboard Nozomi, including a Neutral Mass Spectrometer built by NASA.

The images were first recognised over 50 years ago, but were then lost after doubts were cast on their authenticity.

Now, one German scientist, Dr Michael Rappenglueck, of Munich University, says it is time the pictures were reassessed.

And there could be other surprises awaiting archaeologists, he believes, when they look not at the walls of prehistoric painted caves, but at the floor.

The faces on this page were discovered carved on the floor of a cave at La Marche in the Lussac-les-Chateaux area of France.

The cave system was discovered in 1937 by French scientist Leon Pencard, who excavated it for five years. Over 1,500 slabs were found on which images were etched.

The pictures are difficult to interpret. Sometimes several images are superimposed on one another. But to the trained and expectant eye they reveal extraordinary wonders.

From the La Marche caves there are lions, bears, antelope, horses - and 155 lifelike human figures.

These images of "real people" - male and female faces, people in robes, hats and boots - may date back 15,000 years. This was long before the rise of the great civilisations and a time when Europe was firmly in the grip of an Ice Age.

If correct, this would make them far older, for example, than the symbolic face recently recognised, carved into a rock at Stonehenge.

"They have been completely overlooked by modern science," Dr Rappenglueck told BBC News Online. "They were mentioned in a few books many decades ago and dismissed as fakes - and since then nothing."

The portraits were carved into limestone slabs that were then carefully placed on the floor.

The illustrations are not the stick-like figures seen in prehistoric cave paintings ¿ such as the images in the more famous Lascaux cave system that probably date back 17,000 years; or at Chauvet that go back more than 30,000 years.

However, it has sometimes been asked why the animals painted on the walls of such caves are so much more lifelike than the human forms depicted with them.

Could it be because the more sophisticated human pictures were placed on the floor, asks Dr Rappenglueck?

If so, such treasures on the floors of other prehistoric caves may have been accidentally destroyed.

One of the first things that archaeologists used to do when examining such caves was to level and strengthen the floor, not thinking that what was under their feet could be just as significant as what was on the cave walls.

In Lascaux, for example, the floor was obliterated to make way for visitors in the 1950s. There is no way of knowing if anything significant was destroyed.

Dr Rappenglueck speculates that many archaeological wonders could have been covered up.

"On the floors of one cave I noticed a series of pits arranged in the shape of the Pleiades (also known as the Seven Sisters) star cluster," he said.

Drawings of the Pleiades have been found by Dr Rappenglueck on the walls of many Neolithic caves in several parts of Europe, but until now no cosmic marks had been found on cave floors.

He speculates that the small holes could have been filled with animal fat and set alight mimicking the flickering stars in the sky.

"Perhaps this is the origin of the candlelit festivals of the Far East where lighted candles are held in the shape of the Pleiades. Perhaps it is a tradition that stretches back tens of thousands of years into our Stone Age past."

In a stark shift for the Bush administration, the United States has sent a climate report to the United Nations detailing specific and far-reaching effects that it says global warming will inflict on the American environment.

In the report, the administration for the first time mostly blames human actions for recent global warming. It says the main culprit is the burning of fossil fuels that send heat-trapping greenhouse gases into the atmosphere.

But while the report says the United States will be substantially changed in the next few decades — "very likely" seeing the disruption of snow-fed water supplies, more stifling heat waves and the permanent disappearance of Rocky Mountain meadows and coastal marshes, for example — it does not propose any major shift in the administration's policy on greenhouse gases.

It recommends adapting to inevitable changes. It does not recommend making rapid reductions in greenhouse gases to limit warming, the approach favored by many environmental groups and countries that have accepted the Kyoto Protocol, a climate treaty written in the Clinton administration that was rejected by Mr. Bush.

The new document, "U.S. Climate Action Report 2002," strongly concludes that no matter what is done to cut emissions in the future, nothing can be done about the environmental consequences of several decades' worth of carbon dioxide and other heat-trapping gases already in the atmosphere.

Its emphasis on adapting to the inevitable fits in neatly with the climate plan Mr. Bush announced in February. He called for voluntary measures that would allow gas emissions to continue to rise, with the goal of slowing the rate of growth.

Yet the new report's predictions present a sharp contrast to previous statements on climate change by the administration, which has always spoken in generalities and emphasized the need for much more research to resolve scientific questions.

The report, in fact, puts a substantial distance between the administration and companies that produce or, like automakers, depend on fossil fuels. Many companies and trade groups have continued to run publicity and lobbying campaigns questioning the validity of the science pointing to damaging results of global warming.

The distancing could be an effort to rebuild Mr. Bush's environmental credentials after a bruising stretch of defeats on stances that favor energy production over conservation, notably the failure to win a Senate vote opening the Arctic National Wildlife Refuge to exploratory oil drilling.

But the report has alienated environmentalists, too. Late last week, after it was posted on the Web site of the Environmental Protection Agency, private environmental groups pounced on it, saying it pointed to a jarring disconnect between the administration's findings on the climate problem and its proposed solutions.

"The Bush administration now admits that global warming will change America's most unique wild places and wildlife forever," said Mark Van Putten, the president of the National Wildlife Federation, a private environmental group. "How can it acknowledge global warming is a disaster in the making and then refuse to help solve the problem, especially when solutions are so clear?"

Scott McClellan, a White House spokesman, said, "It is important to move forward on the president's strategies for addressing the challenge of climate change, and that's what we're continuing to do."

Many companies and trade groups had sought last year to tone down parts of the report, the third prepared by the United States under the requirements of a 1992 climate treaty but the first under President Bush.

For the most part, the document does not reflect industry's wishes, which were conveyed in letters during a period of public comment on a draft last year.

The report emphasizes that global warming carries potential benefits for the nation, including increased agricultural and forest growth from longer growing seasons, and from more rainfall and carbon dioxide for photosynthesis.

But it says environmental havoc is coming as well. "Some of the goods and services lost through the disappearance or fragmentation of natural ecosystems are likely to be costly or impossible to replace," the report says.

The report also warns of the substantial disruption of snow-fed water supplies, the loss of coastal and mountain ecosystems and more frequent heat waves. "A few ecosystems, such as alpine meadows in the Rocky Mountains and some barrier islands, are likely to disappear entirely in some areas," it says. "Other ecosystems, such as Southeastern forests, are likely to experience major species shifts or break up into a mosaic of grasslands, woodlands and forests."

Despite arguments by oil industry groups that the evidence is not yet clear, the report unambiguously states that humans are the likely cause of most of the recent warming. Phrases were adopted wholesale from a National Academy of Sciences climate study, which was requested last spring by the White House and concluded that the warming was a serious problem.

A government official familiar with the new report said that it had been under review at the White House from January until mid-April, but that few substantive changes were made.

Without a news release or announcement, the new report was shipped last week to the United Nations offices that administer the treaty and posted on the Web (www.epa .gov/globalwarming/publications /car/).

A senior administration official involved in climate policy played down the significance of the report, explaining that policies on emissions or international treaties would not change as a result.

Global warming has become a significant, if second-tier, political issue recently, particularly since James M. Jeffords, the Vermont independent, became chairman of the Senate Environment and Public Works Committee last year. Mr. Jeffords has criticized the president's policy.

The new report is the latest in a series on greenhouse gases, climate research, energy policies and related matters that are required of signatories to the United Nations Framework Convention on Climate Change, which was signed by Mr. Bush's father and ratified by the Senate.

The convention lacks binding obligations to reduce gas emissions like those in the Kyoto Protocol.

Mr. Bush and administration officials had previously been careful to avoid specifics and couch their views on coming climate shifts with substantial caveats. The president and his aides often described climate change as a "serious issue," but rarely as a serious problem.

The report contains some caveats of its own, but states that the warming trend has been under way for several decades and is likely to continue.

"Because of the momentum in the climate system and natural climate variability, adapting to a changing climate is inevitable," the report says. "The question is whether we adapt poorly or well."

Several industry groups said the qualifications in parts of the report were welcome, but added that the overall message was still more dire than the facts justified and would confuse policy makers.

Dr. Russell O. Jones, a senior economist for the American Petroleum Institute who wrote a letter to the Environmental Protection Agency a year ago seeking to purge projections of specific environmental impacts from the report, said it was "frustrating" to see that they remained.

"Adding the caveats is useful, but the results are still as meaningless," Dr. Jones said.

DENVER, Colorado (CNN) -- Officials issued a plea Tuesday for 800 more firefighters to join those battling what has been called the largest wildfire in Colorado history, which had burned nearly 90,000 acres by nightfall.

The firefighters responding from across the country will join more than 500 who have been fighting the so-called Hayman fire since the weekend.

Fanned by northeasterly winds, the blaze consumed 10,000 acres Tuesday and threatened Denver's southern suburbs, said Joe Colwell, a spokesman for the interagency force fighting the fire.

Wednesday could bring similar conditions, he said late Tuesday.

"We have an extreme potential for growth," Colwell said. "It's hard to predict what this thing will do."

By day's end, the fire had destroyed 21 homes and 510 other structures since it began Saturday.

The fire, which sprung from an illegal campfire, had forced families to evacuate from 1,500 homes, and 2,500 more homes were threatened, Colwell said. He was not sure how many people had been evacuated.

Firefighters had contained about 5 percent of the blaze by day's end, Colwell said

At least 205 people are dead, and hundreds more are missing, in catastrophic floods in north-western China which some local reports describe as the worst in the area for more than a century.

The area has seen a week of torrential rain, and in the worst affected area - south of the city of Xian - close to half a metre of rain fell in two days, in what is normally an arid part of China.

Rivers that had been dry for years turned into raging torrents, sweeping away roads, destroying tens of thousands of homes, and bringing down a railway bridge in Xian just three minutes after a train crossed it.

Chinese Premier Zhu Rongji has warned that worse flooding may take place this summer, while several tens of thousands of soldiers have joined rescue operations in at least seven provinces.

Meanwhlie, Beijing has approved millions of yuan of emergency funding to help shore up river banks and relocate Chinese who lost their homes in the deluge.

While inspecting the provinces of Hubei, Hunan, Jiangxi and Anhui, earlier this week, Zhu asked officials to prepare for "even more severe flooding than that of 1998."

Thousands perished in the floods four years ago, described as the worst in at least half a century.

SHOW LOW, Arizona (CNN) -- A massive wildfire threatened Friday to draw in a smaller blaze and create a gargantuan burn in east-central Arizona that could blacken more than 300,000 acres, firefighters said.

Winds of 40 mph whipped the 120,000-acre Rodeo fire, already labeled Arizona's worst ever by Gov. Jane Dee Hull, into a frenzy and pushed it to the northeast.

"The fire's going to raise its head and get up and run today," said fire information officer Jim Paxon. "We are very much not in control. Nature is in control."

Paxon said officials revised their estimate of the fire's size up from 85,000 acres to 120,000 acres after high-altitude infrared photography showed a greater area burning than seen during a visual estimate done earlier by experts in a helicopter closer to the ground.

Officials feared winds could shift to the east and drive the Rodeo fire toward more populated areas, Paxon said. The blaze has already forced the evacuation of several thousand people.

SHOW LOW, Arizona (CNN) -- A monstrous wildfire that has burned more than 330,000 acres crept toward the largely abandoned town of Show Low Monday and charred more than 100 homes in its path.

President Bush plans to stop in Arizona on his way Tuesday to the G-8 summit in Canada to get an aerial tour of the Rodeo-Chediski fire that has forced the evacuation of about 30,000 residents along eastern Arizona's Mogollon Rim.

He will be briefed by emergency and rescue teams and will visit with families and firefighters. (Full story)