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IMPORTANT NEWS
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30th July, 2006
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21st July, 2006
With hockey sticks in hand, U.S. legislators skeptical of global warming fired shots last week at what has become an iconic image in the debate. But their attack failed to change the outcome of the contest. Instead, scientists and politicians of every stripe agreed that the world is warming and that global warming is a serious issue. They also agreed to disagree about what's causing it.
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19th July, 2006
The local effect of atmospheric aerosols can be greater than the greenhouse effect
A scientist at the Weizmann Institute of Science and his colleagues caused a storm in the atmospheric community when they suggested a few years back that tiny air-borne particles, known as aerosols, may be one of the main culprits causing climate change – having, on a local scale, an even greater impact than the greenhouse gases effect. Attempts to understand how these particles influence clouds have generated many uncertainties. A new paper by Dr. Ilan Koren of the Environmental Studies and Energy Research Department and Dr. Yoram Kauffman of the NASA/Goddard Space Flight Center, USA,* published in Science Express online, weaves together two opposing effects of atmospheric aerosols to provide a comprehensive picture of how they may be affecting our climate.
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18th July, 2006
The European Alps could lose some 80 percent of their glacier cover by the end of this century, if summer air temperatures rise by 3 oC. And if temperatures increase by 5 degC, the Alps would become almost completely ice-free by 2100. These are the conclusions of numerical modeling experiments by scientists from the University of Zurich, Switzerland. The study will be published 15 July in Geophysical Research Letters, a journal of the American Geophysical Union.
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2nd July, 2006
The Antarctic ozone hole's recovery is running late. According to a new NASA study, the full return of the protective ozone over the South Pole will take nearly 20 years longer than scientists previously expected.
Scientists from NASA, the National Oceanic and Atmospheric Administration and the National Center for Atmospheric Research in Boulder, Colo., have developed a new tool, a math-based computer model, to better predict when the ozone hole will recover.
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2nd July, 2006
Scientists testing the deep geologic disposal of the greenhouse gas carbon dioxide are finding that it's staying where they put it, but it's chewing up minerals. The reactions have produced a nasty mix of metals and organic substances in a layer of sandstone 1550 meters down, researchers report this week in Geology. At the same time, the CO2 is dissolving a surprising amount of the mineral that helps keep the gas where it's put. Nothing is leaking out so far, but the phenomenon will need a closer look before such carbon sequestration can help ameliorate the greenhouse problem, say the researchers.
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30th June, 2006
The last decades of the 20th century were most likely warmer than any comparable period in the past 1000 years, a National Research Council (NRC) panel announced at a press briefing here last week. The expert committee thus confirms the outlines of the near-iconic 'hockey stick' temperature curve--a long cooling followed by a sharp warming during the past millennium--that had become a favorite target of greenhouse contrarians. But the committee also says the evidence in parts of the stick is fuzzier than the public and many scientists might have thought.
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19th April, 2006
Earth’s plant life will not be able to “store” excess carbon from rising atmospheric carbon dioxide levels as well as scientists once thought because plants likely cannot get enough nutrients, such as nitrogen, when there are higher levels of carbon dioxide, according to scientists publishing in this week’s issue of the journal Nature.
That, in turn, is likely to dampen the ability of plants to offset increases in atmospheric carbon dioxide.
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19th April, 2006
A research consortium funded by the National Science Foundation (NSF) and led by the Scripps Institution of Oceanography at the University of California, San Diego, has successfully sent a fleet of aerial drones through the pollution-filled skies over the Indian Ocean, thereby achieving an important milestone in the tracking of pollutants responsible for dimming Earth's atmosphere.
The instrument-bearing autonomous unmanned aerial vehicles (AUAVs) completed 18 successful data-gathering missions in the vicinity of the Maldives, an island chain nation south of India, said Scripps scientist V. Ramanathan.
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31st March, 2006
Startling amounts of ice slipping into the sea have taken glaciologists by surprise; now they fear that this century's greenhouse emissions could be committing the world to a catastrophic sea-level rise
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31st March, 2006
Meteorological observations show that surface temperature of the western side of the Antarctic Peninsula has increased at a rate faster than that of any other region on Earth in the last 50 years. However, there have been few statistically significant surface temperature changes across the rest of Antarctica, which may even have cooled slightly in some places during recent decades. In order to help provide a more complete picture of how temperatures in the Antarctic troposphere have changed, Turner et al. (p. 1914) examined recently released radiosonde data from 1971 to 2003. The Antarctic middle troposphere has warmed by 0.5°C or more per decade during the winters during that time. Although this rise has been detected, its cause is still unknown.
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23rd March, 2006
NASA scientists have found that a major form of global air pollution involved in summertime “smog” has also played a significant role in warming the Arctic.
In a global assessment of the impact of ozone on climate warming, scientists at the NASA Goddard Institute for Space Studies (GISS), New York, evaluated how ozone in the lowest part of the atmosphere changed temperatures over the past 100 years. Using the best available estimates of global emissions of gases that produce ozone, the GISS computer model study reveals how much this single air pollutant, and greenhouse gas, has contributed to warming in specific regions of the world.
According to this new research, ozone was responsible for one-third to half of the observed warming trend in the Arctic during winter and spring. Ozone is transported from the industrialized countries in the Northern Hemisphere to the Arctic quite efficiently during these seasons. The findings have been accepted for publication in the American Geophysical Union’s Journal of Geophysical Research-Atmospheres.
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27th January, 2006
As 2005 draws to a close, climate scientists are making their annual pronouncements on how its temperatures compare to historical records. And although this year is among the warmest ever recorded, small differences in the claims highlight the uncertainty of such rankings.
Depending on whom one believes, 2005 will end up just above or below 1998 as the hottest year on record. Most significant, climate scientists say, is that this year's readings occurred without the help of a major El Niño event. 'In just seven years, the background global temperature has increased to a level equal to the peak in the 1997–98 El Niño,' says James Hansen, a researcher at NASA's Goddard Institute for Space Studies in New York City.
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27th January, 2006
The year 2005 was likely the hottest year in more than a century. According to a study by the NASA Goddard Institute for Space Studies (GISS) examining temperatures around the world, 2005 was either the warmest or tied for the warmest ever recorded. According to the GISS team, global warming is now 0.6°C (about 1°F) over the past 30 years, and 0.8°C (about 1.4°F) over the past 100 years.
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3rd January, 2006
Dutch scientists are putting together remarkable maps showing pollution over Europe and other regions of the globe.
Using the US space agency's Aura satellite, the team can look right down to the troposphere, the lowest part of the atmosphere where we all live.
The Ozone Monitoring Instrument (Omi) and other key equipment on Aura can build a daily picture of air quality
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15th December, 2005
The year 2005 marks the twentieth anniversary of the discovery of the ozone hole and the first full year that NASA’s Aura satellite has provided detailed images of the hole. Aura was launched in 2004 to monitor the Earth’s atmosphere, including the health of the delicate ozone layer. The Ozone Monitoring Instrument on Aura collected the data used to create this image on September 11, 2005, when the ozone hole covered 27 million square kilometers—its peak size for the season. Deep blue shows where ozone levels were low enough to be considered part of the ozone hole. New research shows that the ozone layer may be slower in recovering than previously thought.
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9th November, 2005
If humans continue to use fossil fuels in a business as usual manner for the next several centuries, the polar ice caps will be depleted, ocean sea levels will rise by seven meters and median air temperatures will soar 14.5 degrees warmer than current day.
These are the stunning results of climate and carbon cycle model simulations conducted by scientists at the Lawrence Livermore National Laboratory. By using a coupled climate and carbon cycle model to look at global climate and carbon cycle changes, the scientists found that the earth would warm by 8 degrees Celsius (14.5 degrees Fahrenheit) if humans use the entire planet’s available fossil fuels by the year 2300.
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26th October, 2005
Storms will dump heavier rain and snow around the world as Earth’s climate warms over the coming century, according to several leading computer models. Now a study by scientists at the National Center for Atmospheric Research (NCAR) explains how and where warmer oceans and atmosphere will produce more intense precipitation. The findings recently appeared in Geophysical Research Letters, a publication of the American Geophysical Union.
The greatest increases will occur over land in the tropics, according to the study. Heavier rain or snow will also fall in northwestern and northeastern North America, northern Europe, northern Asia, the east coast of Asia, southwestern Australia, and parts of south-central South America during the 21st century.
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26th October, 2005
New evidence from climate records of the past provides some of the strongest indications yet of a direct link between tropical warmth and higher greenhouse gas levels, say scientists at the University of California, Santa Barbara. The present steady rise in tropical temperatures due to global warming will have a major impact on global climate and could intensify destructive hurricanes like Katrina and Rita.
The new evidence linking past tropical ocean temperatures to levels of atmospheric greenhouse gases is published in this week’s Science Express, the on-line publication of the journal Science. The authors are Martin Medina-Elizalde, graduate student in the Department of Earth Science and the Interdepartmental Program in Marine Science at UC Santa Barbara, and David Lea, professor in UCSB’s Department of Earth Science and the Marine Science Institute.
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26th October, 2005
The most comprehensive climate model to date of the continental United States predicts more extreme temperatures throughout the country and more extreme precipitation along the Gulf Coast, in the Pacific Northwest and east of the Mississippi.
The climate model, run on supercomputers at Purdue University, takes into account a large number of factors that have been incompletely incorporated in past studies, such as the effects of snow reflecting solar energy back into space and of high mountain ranges blocking weather fronts from traveling across them, said Noah S. Diffenbaugh, the team’s lead scientist. Diffenbaugh said a better understanding of these factors—coupled with a more powerful computer system on which to run the analysis—allowed the team to generate a far more coherent image of what weather we can expect to encounter in the continental United States for the next century. Those expectations, he said, paint a very different climate picture for most parts of the country.
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5th October, 2005
According to the calculations of scientists at the Max Planck Institute for Meteorology in Hamburg, over the next century the climate will change more quickly than it ever has in the recent history of the earth. These results come from the latest climate model calculations from the German High Performance Computing Centre for Climate and Earth System Research.
The global temperature could rise by up to four degrees by the end of the century. Because of this warming, the sea level could rise on average by as many as 30 centimeters (11.8 inches). The scientists expect that under certain conditions, the sea ice in the arctic will completely melt. In Europe, summers will be drier and warmer, and this will affect agriculture. The winters will become warmer and wetter. Another consequence of the heated atmosphere will be extreme events like heavy precipitation with floods.
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5th October, 2005
At least 10 to 30 percent of global warming measured during the past two decades may be due to increased solar output rather than factors such as increased heat-absorbing carbon dioxide gas released by various human activities, two Duke University physicists report.
The physicists said that their findings indicate that climate models of global warming need to be corrected for the effects of changes in solar activity. However, they emphasized that their findings do not argue against the basic theory that significant global warming is occurring because of carbon dioxide and other “greenhouse” gases.
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21st September, 2005
Warming in the Arctic is stimulating the growth of vegetation and could affect the delicate energy balance there, causing an additional climate warming of several degrees over the next few decades. A new study indicates that as the number of dark-colored shrubs in the otherwise stark Arctic tundra rises, the amount of solar energy absorbed could increase winter heating by up to 70 percent. The research will be published 7 September in the first issue of the Journal of Geophysical Research-Biogeosciences, published by the American Geophysical Union.
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21st September, 2005
An Earth System model developed by researchers at the University of Illinois at Urbana-Champaign indicates that the best location to store carbon dioxide in the deep ocean will change with climate change.
The direct injection of carbon dioxide deep into the ocean has been suggested as one method to help control rising carbon dioxide levels in the atmosphere and mitigate the effects of global warming. But, because the atmosphere interacts with the oceans, the net uptake of carbon dioxide and the oceans’ sequestration capacity could be affected by climate change.
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21st September, 2005
Humans have been tinkering with greenhouse gas levels in Earth’s atmosphere for at least 2,000 years and probably longer, according to a surprising new study of methane trapped in Antarctic ice cores conducted by an international research team.
The study showed wild gyrations of methane from biomass burning from about 1 A.D. to present, said Dominic Ferretti, lead study author and a University of Colorado at Boulder researcher with a joint appointment at the National Institute of Water and Atmospheric Research, or NIWA in Wellington, New Zealand. Scientists had expected to see slowly increasing concentrations of methane, a major greenhouse gas produced primarily by burning and anaerobic activity from agriculture, livestock and natural sources, up until the onset of the Industrial Revolution in the late 1700s, he said.
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24th August, 2005
Climate change could be good news for Scottish farmers, according to ESRC funded research at the University of Stirling. Rising temperatures and increased carbon dioxide levels could mean increased yields and a boost to local economies, according to Professor Nick Hanley, who led the project. The research findings are based on a series of interlinked models, which analyzed the effects of projected changes in Scotland’s weather on land use, regional economies and biodiversity. The possible effects of reform to the EU Common Agricultural Policy (CAP) were also taken into account.
‘We were quite surprised to find that global warming is not necessarily a bad thing,’ says Nick Hanley. ‘Rising temperatures will permit farmers to grow more productive, faster developing crops and increase the intensity of livestock farming. At the same time, the extra carbon dioxide in the atmosphere will reduce the need for artificial fertilizers and this will offset any negative economic effects of climate change.’
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24th August, 2005
The noxious haze that prompted Malaysian officials to declare an air quality emergency in many locations in early August 2005 had eased after a shift in the winds and rain cleared the air. The haze was being generated by intense forest fires burning in Sumatra. Smoke began to build up over Malaysia on August 2, 2005, closing schools and businesses in the worst haze crisis since 1997-1998, the Associated Press reported. The haze lifted starting on August 13, though the fires were still burning.
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17th August, 2005
For the first time, new climate observations and computer models provide a consistent picture of recent warming of the tropical atmosphere.
Over the past decade, scientific evidence from a variety of sources has implicated human-caused increases in greenhouse gases as a major driver of recent climate change. A key argument used to rebut such findings relates to satellite records of temperature change in the troposphere—the lowest layer of Earth’s atmosphere.
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17th August, 2005
The impact of global warming has become obvious in high latitude regions, including Alaska, Siberia and the Arctic, where melting ice and softening tundra are causing profound changes. But, contrary to popular belief, the most serious impact in the next century likely will be in the tropics, says a group of researchers headed by a University of Washington (UW) ecologist.
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17th August, 2005
A new NASA-funded study finds that predicted increases in precipitation due to warmer air temperatures from greenhouse gas emissions may actually increase sea ice volume in the Antarctic’s Southern Ocean. This adds new evidence of potential asymmetry between the two poles, and may be an indication that climate change processes may have different impact on different areas of the globe.
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10th November, 2004
Wind farms can change the weather, according to a model of how these forests of giant turbines interact with the local atmosphere. And the idea is backed up by observations from real wind farms.
Somnath Baidya Roy from Princeton University, and his colleagues modelled a hypothetical wind farm consisting of a 100 by 100 array of wind turbines, each 100 metres tall and set 1 kilometre apart.
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10th November, 2004
International action to cut greenhouse gases is on the way, a leading British expert on the environment believes.
Sir Crispin Tickell, a former diplomat and government adviser, says urgent action is needed because climate change is more serious even than terrorism.
Many in the US administration are 'in a state of denial', he says, but other US attitudes on climate are changing fast.
In a speech in Cambridge Sir Crispin says he thinks the world will finally act together to confront the threat.
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10th November, 2004
With a little help from good weather, air in Los Angeles was the cleanest on record this year, regulators said Thursday.
Still, the region's air quality remained the worst in the nation by one key measure, said Sam Atwood, a spokesman for the South Coast Air Quality Management District.
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10th November, 2004
Methane, a gas that contributes to warming our planet, is produced by natural processes and human activities. Increased amounts of methane and other greenhouse gases in our atmosphere are warming the Earth beyond its average temperature. Carbon, heat and moisture are known to influence methane production by single-celled bacteria, called Archaea. Under normal conditions, these microbes consume organic carbon in the soil for energy and release methane as a byproduct. Many types of bacteria thrive in the wetland environment. When acid rain drops sulfate onto wetlands, another type of bacteria that reduce sulfates are able to out compete the Archaea, limiting the total production of methane.
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29th October, 2004
Recent storms, droughts and heat waves are probably being caused by global warming, which means the effects of climate change are coming faster than anyone had feared, climate experts said on Thursday.
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13th October, 2004
Climate experts have cautioned that a reported consecutive annual jump in the quantity of carbon dioxide in the atmosphere might be an anomaly, without ruling out it was a sign of rapid global warming.
For the first time, carbon dioxide levels in the atmosphere rose by more than two parts per million for two years running, from 2000 to 2001, according to figures recorded by a US scientist and published in the British press.
Climate experts said that the figures may be an anomaly but that they raised the alarm that climate change may be happening faster than previously believed and that governments around the world should take notice.
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13th October, 2004
While Antarctica has mostly cooled over the last 30 years, the trend is likely to rapidly reverse, according to a computer model study by NASA researchers. The study indicates the South Polar Region is expected to warm during the next 50 years.
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13th October, 2004
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11th October, 2004
It has been a long wait since the Kyoto protocol was signed in the early hours of 11 December 1997. Next year, if Russia sticks to the commitment it made last week, the treaty will at last come into force. And that will allow the world to get on with what really matters: drawing up the successor to Kyoto.
For if ardent greens and out-and-out sceptics can agree on anything, it is that Kyoto will not even come close to solving the problem of climate change. It is, as the UN Environment Programme director Klaus Toepfer said in a statement last week, “only the first step in a long journey”.
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6th October, 2004
Scientists are working to understand why the lower atmosphere isn't heating up as fast as some global warming models predict.
How could the globe be warming and not warming at the same time?
That's the riddle posed to climatologists by satellite and radiosonde (balloon-borne instrument for making atmospheric measurements) data which show that while the Earth's surface has been warming over the past decades, the lowest layer of the atmosphere shows a weaker warming trend.
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15th September, 2004
Britain's Tony Blair pledged on Tuesday to force international action on global warming, despite the reluctance of big powers like the United States.
Blair promised to make the issue a centerpiece of Britain's presidency of the G8 industrialized countries in 2005 and laid out a three-point international strategy to tackle a phenomenon he said could become 'irreversible in its destructive power.'
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15th September, 2004
Millions of people across the globe are set to die early due to extreme weather events such as floods and heat waves caused by climate change, a British scientist said Tuesday.
Professor Mike Pilling cited the heatwave in Europe last year that killed thousands of people from a combination of heat exhaustion and an increase in atmospheric pollution.
'We will experience an increase in extreme weather events,' he told reporters at the annual meeting of the British Association for the Advancement of Science. 'There are predictions of a 10-fold increase in heat waves.
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15th September, 2004
The smudges of dark blue on this Envisat-derived ozone forecast trace the start of what has unfortunately become an annual event: the opening of the ozone hole above the South Pole.
'Ever since this phenomenon was first discovered in the mid-1980s, satellites have served as an important means of monitoring it,' explained José Achache, ESA Director of Earth Observation Programmes. 'ESA satellites have been routinely observing stratospheric ozone concentrations for the last decade.
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15th September, 2004
Recovery of a new ice core in Antarctica that extends back 740,000 years -- nearly twice as long as any other ice core record -- is extremely important and will help scientists better understand the Earth's climate and issues related to global warming, according to a University of Colorado at Boulder professor.
The new ice core, announced June 9 by the European Project for Ice Coring in Antarctica, or EPICA, reaches far enough back in time to give scientists 'a first shot at looking at climate and greenhouse gases during interglacial periods when humans had nothing to do with climate change,' said geological sciences Professor James White.
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8th September, 2004
Don't tell the health and safety people but Dr Bunsen Honeydew and his trusty assistant, Beaker, have topped a poll of the UK's favourite cult TV boffins.
The crazy duo whose experiments usually end up destroying their Muppet Labs facility received a third of the votes.
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5th September, 2004
A technique borrowed from the surface physics community is helping chemists and atmospheric scientists understand the complex chemical reactions that occur on low-temperature ice.
Researchers at the Georgia Institute of Technology have used electron-stimulated desorption to study chemical reactions in icy surfaces. The work could lead to a better understanding of chemical reactions taking place in Antarctica, as well as in stratospheric ice crystals.
Known as electron-stimulated desorption (ESD), the technique uses low-energy electrons to locally probe surfaces, differentiating their characteristics from those of the bulk material below them. Using ESD, researchers at the Georgia Institute of Technology have demonstrated that hydrochloric acid (HCl) quickly dissociates upon contact with icy surfaces – even at temperatures well below 100 degrees Kelvin, conditions seen naturally only in the outer solar system.
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5th September, 2004
A common mineral can remove carbon dioxide from combustion gases, but in its natural state, it is glacially slow. Now, a team of Penn State researchers is changing serpentine so that it sequesters the carbon dioxide from fossil fuel burning in hours, not eons.
“Serpentine naturally sequesters carbon dioxide over geologic time, but it is too slow to help us,” says Dr. M. Mercedes Maroto-Valer, assistant professor of energy and geo-environmental engineering and program coordinator for sustainable energy, the Energy Institute.
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5th September, 2004
This image shows a global map of nitrogen dioxide (NO2) in the troposphere (lower atmosphere) in 2003 ... NO2 (along with other Nitrogen oxides) is a highly reactive gas that is one of the six common air pollutants ... The primary sources of NO2 are motor vehicles, electric utilities, and other industrial, commercial, and residential sources that burn fuels.
The principal sources of NO2 in this image are large, populous urban areas. In addition, heavily industrialized areas, and even individual power plants, are sources of the gas. Biomass burning produces lower concentrations of NO2 that are typically spread over wide areas.
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23rd August, 2004
Air quality scientist Jim Szykman begins his story with a tone that suggests “You’re not going to believe this, but…” He describes how in late summer of 2002, an area of high atmospheric pressure settled in over the industrial Midwest south of Lake Michigan. The soot, smoke, and gases from regional power plants that consistently have some of the country’s highest emission rates began to pile up in the hot, humid, stagnant air. The Environmental Protection Agency’s air quality index values began to exceed 100—a level considered unhealthy for people with lung or heart conditions.
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16th August, 2004
As the scientists have reported in the renowned scientific journal, Physical Review Letters, since 1940 the mean sunspot number is higher than it has ever been in the last thousand years and two and a half times higher than the long term average. The temporal variation in the solar activity displays a similarity to that of the mean temperature of the Earth. These scientific results therefore bring the influence of the Sun on the terrestrial climate, and in particular its contribution to the global warming of the 20th century, into the forefront of current interest.
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15th August, 2004
A hypertext history of how scientists came to (partly) understand what people are doing to change the Earth's climate.
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1st August, 2004
NEW YORK (AP) -- Eight states and New York City are suing five of the nation's power companies to force them to decrease carbon dioxide emissions that contribute to global warming, New York Attorney General Eliot Spitzer said Wednesday. - from the CNN website
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21st July, 2004
An international team of scientists has completed the first comprehensive study of the ocean storage of carbon dioxide derived from human activity, called anthropogenic carbon dioxide, CO2, based on a decade-long survey of global ocean carbon distributions in the 1990s.
The findings, along with those detailed in a companion paper on the impacts of anthropogenic CO2 on the chemistry of the oceans and the potential response of marine animals and plants to changes in CO2 levels, will be published in the July 16 issue of the journal Science.
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14th July, 2004
A powerful new instrument heading to space this Saturday is expected to send back long-sought answers about greenhouse gases, atmospheric cleansers and pollutants, and the destruction and recovery of the ozone layer. Only a cubic yard in size but laden with technical wizardry, the High-Resolution Dynamic Limb Sounder (HIRDLS) will measure a slew of atmospheric chemicals at a horizontal and vertical precision unprecedented in a multi-year space instrument.
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7th July, 2004
The Hollywood film The Day After Tomorrow that is currently 'taking the world by storm', depicts a complete shut-down of the Gulf Stream resulting in a massive global storm that throws the northern hemisphere into an ice age in a matter of days.
This is a media release from the International Geosphere-Biosphere Programme (IGBP).
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7th July, 2004
Widespread fires in West Central Africa produced high levels of pollution that drifted westward over the Atlantic Ocean in June 2004.
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25th February, 2004
The highest layers of the Earth's atmosphere are cooling and contracting, most likely in response to increasing levels of greenhouse gases, according to a new study by scientists at the Naval Research Laboratory (NRL). This contraction could result in longer orbital lifetimes for both satellites and hazardous space debris.
In a paper to be published February 5 in the Journal of Geophysical Research - Space Physics, John Emmert, Michael Picone, Judith Lean, and Stephen Knowles report that the average density of the thermosphere has decreased by about 10 percent during the past 35 years. The thermosphere is the highest layer in the atmosphere, and begins at an altitude of about 90 kilometers [60 miles].
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28th January, 2004
Eleven Earth and space scientists say that a recent paper attributing most climate change on Earth to cosmic rays is incorrect and based on questionable methodology. Writing in the January 27 issue of Eos, published by the American Geophysical Union, Stefan Rahmstorf of the Potsdam Institute for Climate Impact Research and colleagues in Canada, France, Germany, Switzerland, and the United States challenge the cosmic ray hypothesis.
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10th December, 2003
Each August in southern Africa, literally thousands of people equipped with lighters or torches go out into the African savanna, a region dotted with villages and teaming with animals, and intentionally set the dry grasslands ablaze. Long plumes of smoke rise across the continent like hundreds of billowing smokestacks, and herds of animals are sent scurrying across open grassland. Though all these activities are vital to life in Africa, they have a downside in the form of pollution. During fire season, a thick pall of smoke chokes the southern Africa skies for weeks each year. The smoke is laced with a number of gases such as nitrogen oxides, carbon monoxide, and hydrocarbons. These gases react with the intense heat and sunlight to form ozone. Unlike high-flying stratospheric ozone, ground level, tropospheric ozone can lead to a number of respiratory diseases, destroy lung tissue, and cause serious damage to crops. When present in the middle to upper troposphere, the molecules trap thermal radiation emanating from the Earth in the same way as carbon dioxide and other greenhouse gases do. In fact, up to 20 percent of the warming experienced by the Earth over the past 150 years is thought to be from ozone.
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5th November, 2003
Although the large fires that ravaged Southern California in late October 2003 are now under control, they can be blamed for the polluted air that is spreading over the Western States and into the Pacific Ocean. In addition to ash and smoke, the fires released carbon monoxide into the atmosphere as they burned.
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23rd October, 2003
The industrial pollutant ozone, long known to be harmful to many kinds of plants, can also affect the very earth in which they grow.
Researchers at Michigan Technological University and the North Central Research Station of the USDA Forest Service have discovered that ozone can reduce soil carbon formation--a measure of the amount of organic matter being added to the soil. Their findings are published in the Oct. 16 issue of the journal Nature.
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15th October, 2003
This year’s Antarctic ozone hole is the second largest ever observed, according to scientists from NASA, the National Oceanic and Atmospheric Administration (NOAA), and the Naval Research Laboratory (NRL). The Antarctic ozone “hole” is defined as thinning of the ozone layer over the continent to levels significantly below pre-1979 levels. Ozone blocks harmful ultraviolet “B” rays. Loss of stratospheric ozone has been linked to skin cancer in humans and other adverse biological effects on plants and animals.
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22nd September, 2003
Controversial satellite data analysis fuels global warming debate.
Nature Science Update
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8th September, 2003
An ice core recently shipped from Antarctica has yielded its first, eagerly awaited results. The tests confirm that the 3200-metre core dates back at least 750,000 years, making the ice the oldest continuous core ever.
Gases and particles trapped in the layers of an ice core provide information about the Earth's climate and atmosphere. Oxygen and hydrogen isotopes reveal the temperature when the ice formed, for example, while high carbon dioxide and methane levels indicate periods of global warming.
New Scientist September 03
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8th September, 2003
Contrary to common belief, the greenhouse effect may have more to do with water in our atmosphere than gases such as carbon dioxide.
Physics World May 2003
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27th August, 2003
Until about 30 years ago, atmospheric scientists believed that all of the ozone in the lower atmosphere (troposphere) intruded from the upper atmosphere (stratosphere), where it formed by the action of sunlight on oxygen molecules. The work of atmospheric chemists during the 1970s dramatically altered that view. Now we understand that more than half of the ozone in the troposphere comes from chemical interactions within the troposphere itself.
Low Level Ozone - Images from NASA Earth Observatory
This map, derived from satellite data, shows tropospheric ozone distribution in June, July, and August from 1979 to 2000. Considerably more ozone pollution exists in the Northern Hemisphere than in the Southern Hemisphere year round
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31st July, 2003
Almost 30 years after it was first reported that pollutants were destroying the Earth's protective ozone layer, there is clear evidence that the global CFC ban has had an impact.
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