Climate Articles
Sundance film puts human face on climate change
The devastating impact of global warming on communities worldwide is the subject of a powerful Sundance documentary aiming to put a human face on climate change.
Michael Nash's film -- "Climate Refugees" -- is a compelling look at the millions of humans displaced by disasters arising from incremental and rapid ecological changes to the environment and more frequent extreme weather events such as hurricanses, cyclones, fires and tornadoes.
A conference to discuss the subject is to be held on Sunday at the sidelines of the Sundance Film Festival, the annual celebration of independent films in Utah which runs until January 31.
"Three years ago, people concerned about global warming were thinking about how long polar bears would survive," said Nash, whose film is being screened out of competition at Sundance.
"And the fact is that what's happening today is affecting tens of millions of people all over the world," Nash told AFP.
Nash's film includes interviews with experts, political leaders and officials from international and humanitarian organizations while traveling to all corners of the globe to explore the phenomenon.
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Melting Arctic Ice: What Satellite Images Don't See
For scientists studying the health of Arctic sea ice, satellite observations are absolutely essential for providing the big picture. It was satellites that revealed in September 2007 a record minimum ice coverage in the region — the result of a massive summer melt. And it was satellites that showed in 2008 and 2009 the modest recovery of late-summer Arctic ice that suggested to some that the specter of a totally ice-free polar ocean might be somewhat less imminent than feared.
But those high-altitude observations need occasional reality checks from scientists down on the surface. It was during one such on-the-ground research expedition last fall that David Barber, an Arctic climatologist at the University of Manitoba, got an unwelcome surprise.
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Water vapour could be behind warming slowdown
A puzzling drop in the amount of water vapour high in the Earth's atmosphere is now on the list of possible culprits causing average global temperatures to flatten out over the past decade, despite ever-increasing greenhouse-gas emissions.
Although the decade spanning 2000 to 2009 ranks as the warmest on record, average temperatures largely levelled off following two decades of rapid increases.
Researchers have previously eyed everything from the Sun and oceans to random variability in order to explain the pause, which sceptics have claimed shows that climate models are unreliable.
Now a team led by researchers at the National Oceanic and Atmospheric Administration (NOAA) in Boulder, Colorado, report that a mysterious 10% drop in water vapour in the stratosphere — the atmospheric layer that sits 10–50 kilometres above Earth's surface — since 2000 could have offset the expected warming due to greenhouse gases by roughly 25%. Just as intriguingly, their model suggests that an increase in stratospheric water vapour might have boosted earlier warming by about 30% in the 1980s and 1990s. The team's work is published online by Science today.
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Painting roofs white could cool cities - study
WASHINGTON, Jan 28 (Reuters) - Painting all the world's city rooftops white could significantly cool urban areas and perhaps ease the impact of global warming, according to a climate study released on Thursday.
Considered a fanciful notion by some critics, the white-roof idea was championed last year by U.S. Energy Secretary Stephen Chu, a Nobel Physics laureate, and research by scientists at the U.S. National Center for Climate Research indicates it has possibilities.
"Our research demonstrates that white roofs, at least in theory, can be an effective method for reducing urban heat," Keith Oleson, the study's lead author said in a statement. "It remains to be seen if it's actually feasible for cities to paint their roofs white, but the idea certainly warrants further investigation."
Climate change hits cities harder than rural areas because many urban surfaces, including dark-colored asphalt roads and tar-covered roofs, absorb heat from the sun. This creates so-called "heat islands" where temperatures can be 2-5 degrees F (about 1-3 degrees C) higher than in the countryside.
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Healing of ozone hole could aggravate global warming
The hole in the ozone layer is now steadily closing, but chances are that it could aggravate warming in the southern hemisphere, warns a new study.
The Antarctic ozone hole was once regarded as one of the biggest environmental threats, but the discovery of a previously undiscovered feedback shows that it has instead helped to shield this region from carbon-induced warming over two decades.
High-speed winds in the area beneath the hole have led to the formation of brighter summertime clouds, which reflect more of the sun's powerful rays.
'These clouds have acted like a mirror to the sun's rays, reflecting the sun's heat away from the surface to the extent that warming from rising carbon emissions has effectively been cancelled out in this region during the summertime,' said Ken Carslaw, professor at the University of Leeds, who co-authored the research.
'If, as seems likely, these winds die down, rising carbon dioxide emissions could then cause the warming of the southern hemisphere to accelerate, which would have an impact on future climate predictions,' he added.
The key to this newly-discovered feedback is aerosol -- tiny reflective particles suspended within the air that are known by experts to have a huge impact on climate.
Greenhouse gases absorb infrared radiation from the Earth and release it back into the atmosphere as heat, causing the planet to warm up over time. Aerosol works against this by reflecting heat from the sun back into space, cooling the planet as it does so.
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The Ozone Hole Is Mending. Now for the 'But.'
That the hole in Earth's ozone layer is slowly mending is considered a big victory for environmental policy makers. But in a new report, scientists say there is a downside: its repair may contribute to global warming.
It turns out that the hole led to the formation of moist, brighter-than-usual clouds that shielded the Antarctic region from the warming induced by greenhouse gas emissions over the last two decades, scientists write in Wednesday's issue of Geophysical Research Letters.
"The recovery of the hole will reverse that," said Ken Carslaw, a professor of atmospheric science at the University of Leeds and a co-author of the paper. "Essentially, it will accelerate warming in certain parts of the Southern Hemisphere."
The hole in the layer, discovered above Antarctica in the mid-1980s, caused wide alarm because ozone plays a crucial role in protecting life on Earth from harmful ultraviolet radiation.
The hole was largely attributed to the human use of chlorofluorocarbons, chemical compounds found in refrigerants and aerosol cans that dissipate ozone. Under an international protocol adopted in 1987, many countries phased out the compounds, helping the ozone to start reconstituting itself over the Antarctic.
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Warming alarms La. scientists
In a letter filled with citations of peer-reviewed scientific studies, 32 scientists -- including many working on the state's coastal restoration efforts -- told Louisiana Gov. Bobby Jindal that there's a direct link between the rising sea levels eroding the state's coastline and greenhouse gases produced by the state's industries.
"We believe that the scientific evidence is compelling that sea level is highly likely to rise at faster rates than in the recent past and that this poses severe threats to Louisiana's people, land and coastal ecosystems," said the letter signed by 32 scientists, including 27 from Louisiana universities. "We also believe that substantial scientific evidence shows that healthy coastal wetlands are a necessary ingredient for a sustainable system able to respond to sea-level rise, and are thus a critical part of effective flood and storm protection.
"The amount of sea-level rise that will be experienced depends on the future trajectory of societal greenhouse gas emissions," the letter said. "These emissions are increasing atmospheric and oceanic temperatures, which are leading to concerns about stronger hurricanes, a key vulnerability for Louisiana. It is therefore imperative that these factors be included in the development of policies on coastal protection and restoration, and that such integrated policies be strategically planned and urgently implemented."
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Iconic tall-grass prairie nears extinction, disappearing faster than before
WINNIPEG - The endless sea of shoulder-high prairie grass that greeted settlers of Manitoba's Red River valley centuries ago is near extinction and disappearing at an alarming rate, a new study has found.
Less than one per cent of Canada's original 6,000 square kilometres of tall-grass prairies remains - most of it in Manitoba. The fields are home to more than 1,000 different species and are partially responsible for mitigating potentially devastating spring flooding.
A new study published this month in the journal Biological Conservation has found that what little remains of the tall-grass prairie is disappearing faster than ever before. Nicola Koper, author of the study and ecologist at the University of Manitoba, found more than one-third of the remaining tall-grass prairies have disappeared since they were last surveyed in the 1980s.
Remaining patches of the unique Canadian ecosystem characterized by towering varieties of grass and flowers are being taken over by other species or deteriorating rapidly, she added.
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Methane Causes Vicious Cycle In Global Warming
Carbon dioxide is the gas we most associate with global warming, but methane gas also plays an important role. For reasons that are not well understood, methane gas stopped increasing in the atmosphere in the 1990s. But now it appears to be once again on the rise. Scientists are trying to understand why — and what to do about it.
Methane gas comes from all sorts of sources including wetlands, rice paddies, cow tummies, coal mines, garbage dumps and even termites. Drew Shindell, at NASA's Goddard Institute in New York, says, "It's gone up by 150 percent since the pre-industrial period. So that's an enormous increase. CO2, by contrast, has gone up by something like 30 percent."
Molecule for molecule, methane is much more effective than carbon dioxide at trapping heat in the atmosphere. And that's just part of the trouble.
"Methane is much more complicated once it gets into the atmosphere than something like carbon dioxide is," Shindell says, "and that's because it reacts with a lot of different important chemicals."
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World's glaciers continue to melt at historic rates
Latest figures show the world's glaciers are continuing to melt so fast that many will disappear by the middle of this century
Glaciers across the globe are continuing to melt so fast that many will disappear by the middle of this century, the World Glacier Monitoring Service (WGMS) said today.
The announcement of the latest annual results from monitoring in nine mountain ranges on four continents comes as doubts have been cast on how much climate scientists have exaggerated the problem of glacier melt, which is seen as a leading indicator of how much the planet is heating up.
Last week the head of the Intergovernmental Panel on Climate Change (IPCC) apologised for "a paragraph" in its four-volume 2007 report which warned there was a "very high" risk that the Himalayan glaciers, on which at least half a billion of the world's poorest people depend for water, would disappear by 2035.
However the director of the WGMS, Professor Wilfried Haeberli, said the latest global results indicated most glaciers were continuing to melt at historically high rates.
"The melting goes on," said Haeberli. "It's less extreme than in years [immediately before] but what's really important is the trend of 10 years or so, and that shows an unbroken acceleration in melting."
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UN Panel Regrets Himalayan Exaggeration
The U.N. panel of climate scientists expressed regret on Wednesday for exaggerating how quickly Himalayan glaciers are melting in a report that wrongly projected that they could all vanish by 2035.
Glaciers in the Himalayan mountains are shrinking, but not by as much as climate scientists once stated.
Leaders of the Intergovernmental Panel on Climate Change (IPCC) "regret the poor application of well-established IPCC procedures in this instance", they said in a statement on the flaw in a paragraph of a 938-page scientific report.
They noted that the projection of a thaw by 2035 did not make it to the final summary for policymakers in its latest report in 2007. The summary projected a faster thaw in the coming years for glaciers from the Andes to the Alps.
India and some climate researchers have criticized the IPCC in recent days for over-stating the shrinking of Himalayan glaciers, whose seasonal thaw helps to supply water to nations including China and India.
A disappearance of the glaciers would badly disrupt flows in Asia that are vital for irrigation. The IPCC leaders said they were strongly committed to ensuring a high standard for the reports.
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Oceans 'under new threat'
Scientists are warning of the dangers of ocean acidification which is beginning to have an impact on the fundamental biology of marine ecosystems. In the 250 years since the start of the industrial revolution the acidity of the seas has increased by 30 percent.
Science correspondent Tom Feilden reports on an issue biologists have dubbed the "elephant in the corner" of the climate change debate.
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Global Cooling: What to Believe?
This winter some parts of the world are freezing in record cold conditions. Is this really what global warming looks like?
This winter, Britain has seen the longest cold spell in more than three decades, North America was hit by blizzards that brought frost to Florida, two dozen patients in a psychiatric hospital froze to death on the Caribbean island of Cuba. Surely, global warming has got to be a joke!
That is how the argument goes and the number of comments and articles that promote it around the world is growing. The UK's Daily Mail newspaper, among the most avid proponents of 'global cooling', even proclaimed the beginning of a "mini ice age".
How weird this must sound to an long-term climate trends.
"Nobody would discuss the problem of [Einstein's theory of] relativity in the media. But because we all experience the weather, we all believe that we can assess the global warming problem," complains the renowned German climate scientist Mojib Latif from the Leibniz-Institute for maritime sciences in Kiel.
Scientists like Latif have learned to be suspicious about their instincts and look at their data. So what does the data say for the winter of 2009/10?
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NASA Climatologist Gavin Schmidt Discusses the Surface Temperature Record
Gavin Schmidt, a climatologist at NASA's Goddard Institute for Space Studies (GISS) in New York City, studies why and how Earth's climate varies over time. He offered some context on the annual surface temperature record, a data set that's generated considerable interest -- and some controversy -- in the past. GISS updated its surface temperature record with 2009 data this week, and reported that the last decade was the warmest on record.
NASA's Earth Science News Team: Every year, some of the same questions come up about the temperature record. What are they?
Gavin Schmidt: First, do the annual rankings mean anything? Second, how should we interpret all of the changes from year to year -- or inter-annual variability -- the ups and downs that occur in the record over short time periods? Third, why does NASA GISS get a slightly different answer than the Met Office Hadley Centre does? Fourth, is GISS somehow cooking the books in its handling and analysis of the data?
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Is Antarctica Melting?
There has been lots of talk lately about Antarctica and whether or not the continent's giant ice sheet is melting. One new paper 1, which states there's less surface melting recently than in past years, has been cited as "proof" that there's no global warming. Other evidence that the amount of sea ice around Antarctica seems to be increasing slightly 2-4 is being used in the same way. But both of these data points are misleading. Gravity data collected from space using NASA's Grace satellite show that Antarctica has been losing more than a hundred cubic kilometers (24 cubic miles) of ice each year since 2002. The latest data reveal that Antarctica is losing ice at an accelerating rate, too. How is it possible for surface melting to decrease, but for the continent to lose mass anyway? The answer boils down to the fact that ice can flow without melting.
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Global warming 'speeds' up gas emissions
Rising temperatures are not just a sign of climate change but are also a cause of it, a new study has suggested.
Higher temperatures on the surface of the earth are fuelling a further increase in emissions of methane, Edinburgh University experts found.
Methane is a greenhouse gas which is more potent than carbon dioxide.
The study indicated warmer temperatures in regions which were at higher latitudes increased methane - exacerbating global warming.
Scientists studying atmospheric levels of methane from the world's largest source of the gas, wetlands such as paddy fields, marshes and bogs, found that emissions were increasing in line with rising temperatures.
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Century-Old Antarctic Station Shows Warming
Weather data from the past 107 years have revealed a warming trend since the 1950s.
* More than 100 years of weather data are showing a warming pattern.
* An ozone hole and climate change is behind this trend.
Records of more than a century of weather data from the southern hemisphere's oldest, coldest weather station have revealed an extraordinary burst of warming since 1950 -- but it's not all caused by global warming.
The base at the Islas Orcadas, a remote band of land that looks as if it's been whipped off the tip of the Antarctic Peninsula, was founded by Scots in 1903, and has been manned by Argentines ever since, all of whom collected daily weather data.
That longevity is paying off in terms of getting a better grasp of southern climate changes, explains NOAA climate researcher Susan Solomon and her colleagues in the Jan. 2010 issue of the Journal of Climate.
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Unusual Arctic warmth as north hemisphere shivers
While much of the Northern Hemisphere has shivered in a cold snap in recent weeks, temperatures in the Arctic soared to unusually high levels, U.S. scientists reported.
This strange atmospheric pattern is caused by natural variability and not by rising levels of greenhouse gases. However, it could affect Arctic ice which in turn may impact global warming, said Mark Serreze, director of the U.S. National Snow and Ice Data Center in Colorado.
"It's very warm over the Arctic, with air temperatures locally at 10 to 15 degrees F (5.6 to 8.4 degrees C) warmer than they should be in certain areas," Serreze said in a telephone interview on Monday.
This contrasts with record or near-record cold over much of the eastern United States and Canada, Europe and Asia for the last two weeks of December and the first days of January, the data center reported.
It's due to a large area of high pressure over the Arctic, and a big area of low pressure at the mid-latitudes, where much of the Northern Hemisphere's population is concentrated.
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Major Antarctic glacier is 'past its tipping point'
A major Antarctic glacier has passed its tipping point, according to a new modelling study. After losing increasing amounts of ice over the past decades, it is poised to collapse in a catastrophe that could raise global sea levels by 24 centimetres.
Pine Island glacier (PIG) is one of many at the fringes of the West Antarctic ice sheet. In 2004, satellite observations showed that it had started to thin, and that ice was flowing into the Amundsen Sea 25 per cent faster than it had 30 years before.
Now, the first study to model changes in an ice sheet in three dimensions shows that PIG has probably passed a critical "tipping point" and is irreversibly on track to lose 50 per cent of its ice in as little as 100 years, significantly raising global sea levels.
The team that carried out the study admits their model can represent only a simplified version of the physics that govern changes in glaciers, but say that if anything, the model is optimistic and PIG will disappear faster than it projects.
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Strongest winter storm in at least 140 years whallops Southwest U.S.
The most powerful low pressure system in 140 years of record keeping swept through the Southwest U.S. yesterday, bringing deadly flooding, tornadoes, hail, hurricane force winds, and blizzard conditions. We expect to get powerful winter storms affecting the Southwest U.S. during strong El Niño events, but yesterday's storm was truly epic in its size and intensity. The storm set all-time low pressure records over roughly 10 - 15% of the U.S.--over southern Oregon, and most of California, Nevada, Arizona, and Utah. Old records were broken by a wide margin in many locations, most notably in Los Angeles, where the old record of 29.25" set January 17, 1988, was shattered by .18" (6 mb). Bakersfield broke its record by .30" (10 mb). The record-setting low spawned an extremely intense cold front that rumbled thought the Southwest, and winds ahead of the cold front reached sustained speeds of hurricane force--74 mph--last night at Apache Junction, 40 miles east of Phoenix. Wind gusts as high as 94 mph were recorded in Ajo, Arizona, and a Personal Weather Station in Summerhaven (on top of Mt. Lemmon next to Tucson) recorded sustained winds of 67 mph, gusting to 86 mph, before the power failed. Prescott recorded sustained winds at 52 mph, gusting to 67 as the cold front passed, and high winds plunged visibility to zero in blowing dust on I-10 connecting Phoenix and Tucson. The storm spawned one possible tornado in Arizona, which touched down at 8:32 pm MST in Phoenix near Desert Ridge Mall. No damage or injuries were reported. If verified, it would be only the 7th January tornado in Arizona since record keeping began in 1950.
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231-mph NH wind gust is no longer world's fastest
CONCORD, N.H. - First the Old Man, now the Big Wind. New Hampshire's Mount Washington has lost its distinction as the site of the fastest wind gust ever recorded on Earth, officials at the Mount Washington Observatory said Tuesday.
The concession came three days after the World Meteorological Organization posted a snippet on its Web site saying a panel of experts reviewing extreme weather and climate data turned up a 253 mph gust on Australia's Barrow Island during Cyclone Olivia in 1996.
That tops the 231 mph record set atop Mount Washington on April 12, 1934.
"It's obviously a big disappointment. Having the world record for over six decades was such a part of the soul of this organization and for fans of Mount Washington around the country," said Scot Henley, the observatory's executive director.
The official title at issue is "highest wind gust ever recorded on the surface of the Earth by means of an anemometer." But to most people in New Hampshire, it was simply "the Big Wind," a source of pride in a state that also revered its Old Man of the Mountain, a rock outcropping that appeared to be a man's profile and was featured on the state's quarter.
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(Heart)Breaking News From The United States of Ostriches
The Yale School of Forestry and Environmental Studies released the results of a new national survey on public responses to climate change. This report finds that public concern about global warming has dropped sharply since the fall of 2008:
* The percentage of Americans who think global warming is happening has declined 14 points, to 57 percent.
* The percentage of Americans who think global warming is caused mostly by human activities has dropped 10 points, to 47 percent.
* Only 50 percent of Americans now say they are "somewhat" or "very worried" about global warming, a 13-point decrease.
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