Answer to Energy Crisis? Waste Not, Want Not
rudkla - 24. Okt, 11:38
Global Warming - Globale Erwaermung
Dienstag, 24. Oktober 2006
Montag, 23. Oktober 2006
Why are we looking for military solutions to ecological problems?
War Climates
https://ga3.org/ct/P720pgF1MRU2/
https://ga3.org/ct/P720pgF1MRU2/
rudkla - 23. Okt, 18:48
Global Warming Study Predicts Wild Ride
rudkla - 23. Okt, 11:25
Cracking up: Ice turning to water, glaciers on the move and a planet in peril
rudkla - 23. Okt, 10:42
Sonntag, 22. Oktober 2006
CLIMATE EXTREMES ARE COMING
rudkla - 22. Okt, 09:23
Samstag, 21. Oktober 2006
Ozone layer hole 'bigger than North America'
Sat 21 Oct 2006
ALEX MASSIE IN WASHINGTON
https://news.scotsman.com/scitech.cfm?id=1559032006
THE hole in the ozone layer above Antarctica has grown to the biggest recorded size - larger than the North American continent - say NASA scientists, who yesterday released dramatic images documenting its changes.
The hole is a region where there is severe depletion of the layer of ozone - a form of oxygen - in the upper atmosphere that protects life by blocking ultraviolet rays from the sun. Scientists say made-man gases such as bromine and chlorine cause the hole by damaging the layer.
Paul Newman, atmospheric scientist at NASA's Goddard Space Flight Centre in Greenbelt, Maryland, said: "From September 21 to 30, the average area of the ozone hole was the largest ever observed, at 10.6 million square miles."
The increased size of the hole was blamed on unusual weather patterns. If the stratospheric weather conditions had been normal, the ozone hole would be expected to reach about 8.9 to 9.3 million square miles.
However, colder temperatures result in larger and deeper ozone holes, while warmer temperatures lead to smaller ones.
And this year, the lower stratosphere was about nine degrees Celsius cooler than average. In addition to the vast area covered by the hole, what ozone there is in the skies above Antarctica is thinner than usual this year.
The ozone hole is considered to be the area with total column ozone below
220 "Dobson Units". A reading of 100 Dobson Units means that if all the ozone in the air above a point were brought down to sea-level pressure and cooled to freezing, it would form a layer 1cm thick. A reading of 250 Dobson Units translates to a layer about 2.5cm thick (about an inch).
Satellite measurements observed a low reading of 85 Dobson units of ozone earlier this month. In July, by contrast, the ozone layer had a thickness of 300 Dobson units.
"These numbers mean the ozone is virtually gone in this layer of the atmosphere," said David Hofmann, the director of the global monitoring division at the US National Oceanic and Atmospheric Administration's Earth System Research Laboratory. "The depleted layer has an unusual vertical extent this year, so it appears the 2006 ozone hole will go down as a record-setter."
However, despite the dramatic size of the hole, the long-term prognosis for the ozone layer is healthy.
While there are and will continue to be year-to-year variations in the extent of its coverage, scientists expect a slow but complete recovery by the year 2065.
"I don't think there's a risk of the ozone hole growing and destroying the world," said Ken Caldeira, of the Carnegie Institution of Washington's department of global ecology.
Although CFCs and other dangerous gases that damage the ozone layer can linger in the atmosphere for as long as two generations, the amount of such damaging gases released into the atmosphere peaked in 1995 and has been declining ever since.
This means that, in theory, the ozone layer will have a chance to recover, although at an extremely slow and gradual pace for the next decade. Scientists expect the hole to reduce by just 0.1 to 0.2 per cent a year for the next ten years, before bouncing back more swiftly in later years. NASA also reported that ice was melting in Greenland more quickly than it was being replaced and more rapidly than scientists had believed.
"The results show a dramatic speed-up in the rate of ice-mass loss since the 1990s," said NASA researcher Jay Zwally. "A very large change in a very short time."
In a report published in Science magazine, researchers concluded that Greenland has lost 41 cubic miles of ice along its coast and gained only
14 miles from snowfall in its interior. Sea levels would rise 20ft if Greenland's icecap melted totally. Invisible barrier that protects planet from harmful solar rays
OZONE forms a protective layer high in the Earth's atmosphere, helping to reflect harmful rays from the sun.
Particles of ozone normally exist at levels of about 10 parts per million in a layer between nine to 30 miles above the ground.
However without this thin protective barrier virtually all forms of life from penguins to plants would be affected by ultraviolet radiation, which can cause skin cancer in humans and generally damages DNA, the fundamental building block of life.
Normally, there is a natural cycle of creation and destruction of ozone, a pale-blue gas with a pungent odour, but pollution can adversely effect this process. Warm temperatures on the ground tend to mean colder temperatures in the upper atmosphere, which exacerbates the problem.
Many of the ozone-damaging CFCs - once commonly used in refrigeration, air conditioning and industrial cleaning - were banned in 1985 by the Vienna Convention and in 1987 by the Montreal Protocol.
Related topic
* Climate change https://news.scotsman.com/topics.cfm?tid=52
Informant: binstock
--------
Ozone Hole, Double Record Breaker
NASA and National Oceanic and Atmospheric Administration (NOAA) scientists report this year's ozone hole in the polar region of the Southern Hemisphere has broken records for area and depth.
https://www.truthout.org/issues_06/102306EC.shtml
ALEX MASSIE IN WASHINGTON
https://news.scotsman.com/scitech.cfm?id=1559032006
THE hole in the ozone layer above Antarctica has grown to the biggest recorded size - larger than the North American continent - say NASA scientists, who yesterday released dramatic images documenting its changes.
The hole is a region where there is severe depletion of the layer of ozone - a form of oxygen - in the upper atmosphere that protects life by blocking ultraviolet rays from the sun. Scientists say made-man gases such as bromine and chlorine cause the hole by damaging the layer.
Paul Newman, atmospheric scientist at NASA's Goddard Space Flight Centre in Greenbelt, Maryland, said: "From September 21 to 30, the average area of the ozone hole was the largest ever observed, at 10.6 million square miles."
The increased size of the hole was blamed on unusual weather patterns. If the stratospheric weather conditions had been normal, the ozone hole would be expected to reach about 8.9 to 9.3 million square miles.
However, colder temperatures result in larger and deeper ozone holes, while warmer temperatures lead to smaller ones.
And this year, the lower stratosphere was about nine degrees Celsius cooler than average. In addition to the vast area covered by the hole, what ozone there is in the skies above Antarctica is thinner than usual this year.
The ozone hole is considered to be the area with total column ozone below
220 "Dobson Units". A reading of 100 Dobson Units means that if all the ozone in the air above a point were brought down to sea-level pressure and cooled to freezing, it would form a layer 1cm thick. A reading of 250 Dobson Units translates to a layer about 2.5cm thick (about an inch).
Satellite measurements observed a low reading of 85 Dobson units of ozone earlier this month. In July, by contrast, the ozone layer had a thickness of 300 Dobson units.
"These numbers mean the ozone is virtually gone in this layer of the atmosphere," said David Hofmann, the director of the global monitoring division at the US National Oceanic and Atmospheric Administration's Earth System Research Laboratory. "The depleted layer has an unusual vertical extent this year, so it appears the 2006 ozone hole will go down as a record-setter."
However, despite the dramatic size of the hole, the long-term prognosis for the ozone layer is healthy.
While there are and will continue to be year-to-year variations in the extent of its coverage, scientists expect a slow but complete recovery by the year 2065.
"I don't think there's a risk of the ozone hole growing and destroying the world," said Ken Caldeira, of the Carnegie Institution of Washington's department of global ecology.
Although CFCs and other dangerous gases that damage the ozone layer can linger in the atmosphere for as long as two generations, the amount of such damaging gases released into the atmosphere peaked in 1995 and has been declining ever since.
This means that, in theory, the ozone layer will have a chance to recover, although at an extremely slow and gradual pace for the next decade. Scientists expect the hole to reduce by just 0.1 to 0.2 per cent a year for the next ten years, before bouncing back more swiftly in later years. NASA also reported that ice was melting in Greenland more quickly than it was being replaced and more rapidly than scientists had believed.
"The results show a dramatic speed-up in the rate of ice-mass loss since the 1990s," said NASA researcher Jay Zwally. "A very large change in a very short time."
In a report published in Science magazine, researchers concluded that Greenland has lost 41 cubic miles of ice along its coast and gained only
14 miles from snowfall in its interior. Sea levels would rise 20ft if Greenland's icecap melted totally. Invisible barrier that protects planet from harmful solar rays
OZONE forms a protective layer high in the Earth's atmosphere, helping to reflect harmful rays from the sun.
Particles of ozone normally exist at levels of about 10 parts per million in a layer between nine to 30 miles above the ground.
However without this thin protective barrier virtually all forms of life from penguins to plants would be affected by ultraviolet radiation, which can cause skin cancer in humans and generally damages DNA, the fundamental building block of life.
Normally, there is a natural cycle of creation and destruction of ozone, a pale-blue gas with a pungent odour, but pollution can adversely effect this process. Warm temperatures on the ground tend to mean colder temperatures in the upper atmosphere, which exacerbates the problem.
Many of the ozone-damaging CFCs - once commonly used in refrigeration, air conditioning and industrial cleaning - were banned in 1985 by the Vienna Convention and in 1987 by the Montreal Protocol.
Related topic
* Climate change https://news.scotsman.com/topics.cfm?tid=52
Informant: binstock
--------
Ozone Hole, Double Record Breaker
NASA and National Oceanic and Atmospheric Administration (NOAA) scientists report this year's ozone hole in the polar region of the Southern Hemisphere has broken records for area and depth.
https://www.truthout.org/issues_06/102306EC.shtml
rudkla - 21. Okt, 16:24
Climate Change 'Will Cause Refugee Crisis'
rudkla - 21. Okt, 09:51
Freitag, 20. Oktober 2006
GREENLAND ICE SHEET ON A DOWNWARD SLIDE
NASA
October 19, 2006
https://www.nasa.gov/vision/earth/lookingatearth/greenland_slide.html
For the first time NASA scientists have analyzed data from direct, detailed satellite measurements to show that ice losses now far surpass ice gains in the shrinking Greenland ice sheet.
Using a novel technique that reveals regional changes in the weight of the massive ice sheet across the entire continent, scientists at NASA's Goddard Space Flight Center, Greenbelt, Md., report that Greenland's low coastal regions lost 155 gigatons (41 cubic miles) of ice per year between 2003 and 2005 from excess melting and icebergs, while the high-elevation interior gained 54 gigatons (14 cubic miles) annually from excess snowfall.
"With this new analysis we observe dramatic ice mass losses concentrated in the low-elevation coastal regions, with nearly half of the loss coming from southeast Greenland," said lead author Scott Luthcke of NASA Goddard's Planetary Geodynamics Laboratory. "In the 1990's the ice was very close to balance with gains at about the same level as losses. That situation has now changed significantly, with an annual net loss of ice equal to nearly six years of average water flow from the Colorado River."
The study is based on an innovative use of data from the Gravity Recovery and Climate Experiment (GRACE) satellite that reveals detailed information about where and when the Greenland ice mass has changed. Other recent studies using GRACE observations have reported continent-wide ice mass declines, but none has shown these changes in enough detail for scientists to investigate how much different areas of the ice sheet are losing.
To achieve this more-detailed view of the ice sheet's behavior, Luthcke and his colleagues used a technique that brings GRACE's global view of the Earth down to a more local and frequent view. The pair of GRACE satellites orbiting in close formation detect changes in the Earth's mass directly below them by measuring changes in the distance between the two satellites as the gravitational force of the mass causes each to speed up or slow down.
To achieve this more-detailed view of the ice sheet's behavior, Luthcke and his colleagues used a technique that brings GRACE's global view of the Earth down to a more local and frequent view. The pair of GRACE satellites orbiting in close formation detect changes in the Earth's mass directly below them by measuring changes in the distance between the two satellites as the gravitational force of the mass causes each to speed up or slow down.
Standard GRACE data products infer local mass changes from a global data set of these satellite measurements. The new study used only data from over the Greenland region.
"With this new detailed view of the Greenland ice sheet, we have come a long way toward resolving the differences among recent observations and what we know about how the ice sheet behaves," said co-author Waleed Abdalati, head of Goddard's Cryospheric Sciences Branch. "A consistent picture from the different data sets is emerging."
"The seasonal cycle of increased mass loss during the summer melt season and growth during winter is clearly captured," said co-author Jay Zwally, ICESat project scientist. The new results also capture more precisely where changes are taking place, showing that the losses of ice mass are occurring in the same three drainage systems where other studies have reported increased glacier flow and ice-quakes in outlet glaciers.
GRACE is a joint partnership between NASA and the German Aerospace Center, Deutsches Zentrum für Luft und Raumfahrt. The satellites, launched in 2002, are managed by the Jet Propulsion Laboratory.
Continued monitoring in the future is needed to determine whether this ice loss is a long-term trend, the authors point out. The new study appears in Science Express, the advance edition of the journal Science, on Oct. 19.
Informant: NHNE
October 19, 2006
https://www.nasa.gov/vision/earth/lookingatearth/greenland_slide.html
For the first time NASA scientists have analyzed data from direct, detailed satellite measurements to show that ice losses now far surpass ice gains in the shrinking Greenland ice sheet.
Using a novel technique that reveals regional changes in the weight of the massive ice sheet across the entire continent, scientists at NASA's Goddard Space Flight Center, Greenbelt, Md., report that Greenland's low coastal regions lost 155 gigatons (41 cubic miles) of ice per year between 2003 and 2005 from excess melting and icebergs, while the high-elevation interior gained 54 gigatons (14 cubic miles) annually from excess snowfall.
"With this new analysis we observe dramatic ice mass losses concentrated in the low-elevation coastal regions, with nearly half of the loss coming from southeast Greenland," said lead author Scott Luthcke of NASA Goddard's Planetary Geodynamics Laboratory. "In the 1990's the ice was very close to balance with gains at about the same level as losses. That situation has now changed significantly, with an annual net loss of ice equal to nearly six years of average water flow from the Colorado River."
The study is based on an innovative use of data from the Gravity Recovery and Climate Experiment (GRACE) satellite that reveals detailed information about where and when the Greenland ice mass has changed. Other recent studies using GRACE observations have reported continent-wide ice mass declines, but none has shown these changes in enough detail for scientists to investigate how much different areas of the ice sheet are losing.
To achieve this more-detailed view of the ice sheet's behavior, Luthcke and his colleagues used a technique that brings GRACE's global view of the Earth down to a more local and frequent view. The pair of GRACE satellites orbiting in close formation detect changes in the Earth's mass directly below them by measuring changes in the distance between the two satellites as the gravitational force of the mass causes each to speed up or slow down.
To achieve this more-detailed view of the ice sheet's behavior, Luthcke and his colleagues used a technique that brings GRACE's global view of the Earth down to a more local and frequent view. The pair of GRACE satellites orbiting in close formation detect changes in the Earth's mass directly below them by measuring changes in the distance between the two satellites as the gravitational force of the mass causes each to speed up or slow down.
Standard GRACE data products infer local mass changes from a global data set of these satellite measurements. The new study used only data from over the Greenland region.
"With this new detailed view of the Greenland ice sheet, we have come a long way toward resolving the differences among recent observations and what we know about how the ice sheet behaves," said co-author Waleed Abdalati, head of Goddard's Cryospheric Sciences Branch. "A consistent picture from the different data sets is emerging."
"The seasonal cycle of increased mass loss during the summer melt season and growth during winter is clearly captured," said co-author Jay Zwally, ICESat project scientist. The new results also capture more precisely where changes are taking place, showing that the losses of ice mass are occurring in the same three drainage systems where other studies have reported increased glacier flow and ice-quakes in outlet glaciers.
GRACE is a joint partnership between NASA and the German Aerospace Center, Deutsches Zentrum für Luft und Raumfahrt. The satellites, launched in 2002, are managed by the Jet Propulsion Laboratory.
Continued monitoring in the future is needed to determine whether this ice loss is a long-term trend, the authors point out. The new study appears in Science Express, the advance edition of the journal Science, on Oct. 19.
Informant: NHNE
rudkla - 20. Okt, 22:02
Earth as a different planet
October 18, 2006
https://pubs.acs.org/subscribe/journals/esthag-w/2006/oct/science/cc_earth.html
Drastic changes are only 1 °C away, a team led by a NASA scientist concludes.
The earth is the warmest it has been in the past 10,000 years, according to a new analysis that warns of serious changes ahead.
Global surface temperature has increased by about 0.2 °C per decade in the past 30 years, researchers note in the September 25 issue of Proceedings of the National Academy of Sciences. This warming is larger in the Western Equatorial Pacific than in the Eastern Equatorial Pacific, a change that may have increased the likelihood of strong El Niño events, such as those of 1983 and 1998.
The paper, by James Hansen of NASA’s Goddard Institute for Space Studies and colleagues from Columbia University Earth Institute; Sigma Space Partners, Inc.; and the University of California, Santa Barbara, updates an analysis of surface-temperature change based on instrumental data and observed temperature change made in the 1980s.
The team predicts that if temperatures rise 1 °C, changes will occur rapidly and result in a “different” planet. “Given that a large portion of human-made CO2 will remain in the air for many centuries, sensible policies must focus on devising energy strategies that greatly reduce CO2 emissions,” the team concludes.
Informant: binstock
https://pubs.acs.org/subscribe/journals/esthag-w/2006/oct/science/cc_earth.html
Drastic changes are only 1 °C away, a team led by a NASA scientist concludes.
The earth is the warmest it has been in the past 10,000 years, according to a new analysis that warns of serious changes ahead.
Global surface temperature has increased by about 0.2 °C per decade in the past 30 years, researchers note in the September 25 issue of Proceedings of the National Academy of Sciences. This warming is larger in the Western Equatorial Pacific than in the Eastern Equatorial Pacific, a change that may have increased the likelihood of strong El Niño events, such as those of 1983 and 1998.
The paper, by James Hansen of NASA’s Goddard Institute for Space Studies and colleagues from Columbia University Earth Institute; Sigma Space Partners, Inc.; and the University of California, Santa Barbara, updates an analysis of surface-temperature change based on instrumental data and observed temperature change made in the 1980s.
The team predicts that if temperatures rise 1 °C, changes will occur rapidly and result in a “different” planet. “Given that a large portion of human-made CO2 will remain in the air for many centuries, sensible policies must focus on devising energy strategies that greatly reduce CO2 emissions,” the team concludes.
Informant: binstock
rudkla - 20. Okt, 18:46
Refugees, Disease Big Risk From Global Warming
The world is not doing enough to combat global warming which, left unchecked, could trigger a mass movement of people and have serious consequences for security and health. Experts have said that millions of people in densely populated, low-lying, developing countries such as Bangladesh and parts of China, Indonesia and Vietnam might be forced to move by rising sea levels.
https://www.truthout.org/issues_06/101906EC.shtml
https://www.truthout.org/issues_06/101906EC.shtml
rudkla - 20. Okt, 18:22
