The clouds were bluish-grey with a distinctive cellular pattern of pouches.
They were hanging under another cloud base -- a sure sign of rain to come.
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| ©Mark Smith |
| Menacing sky: mammatus clouds herald an approaching cold front. |
Earth Changes
It was a rare sight over Melbourne, with eye-catching mammatus clouds drifting in from the west.
The clouds were bluish-grey with a distinctive cellular pattern of pouches.
They were hanging under another cloud base -- a sure sign of rain to come.
The clouds were bluish-grey with a distinctive cellular pattern of pouches.
They were hanging under another cloud base -- a sure sign of rain to come.
The Himalaya, the "Roof of the World", source of the seven largest rivers of Asia are, like other mountain chains, suffering the effects of global warming. To assess the extent of melting of its 33 000 km2 of glaciers, scientists have been using a process they have been pioneering for some years. Satellite-imagery derived glacier surface topographies obtained at intervals of a few years were adjusted and compared. Calculations indicated that 915 km2 of Himalayan glaciers of the test region, Spiti/Lahaul (Himachal Pradesh, India) thinned by an annual average of 0.85 m between 1999 and 2004. The technique is still experimental, but it has been validated in the Alps and could prove highly effective for watching over all the Himalayan glacier systems. However, the procedure for achieving a reliable estimate must overcome a number of sources of error and approximation inherent in satellite-based observations.
The researchers started by retrieving satellite data for two periods, 2000 and 2004. A digital field model was extracted for each of them, representing the topography of a ground reference point in digital form and therefore usable in computerized processing. The earliest topography of the area studied was provided by NASA which observed 80% of the Earth's surface during the Shuttle Radar Topographic Mission of February 2000. Then, in November 2004, two 2.5 m resolution images of the same area taken at two different angles were acquired especially by the French satellite Spot5 in the framework of an ISIS (CNES) project.
The researchers started by retrieving satellite data for two periods, 2000 and 2004. A digital field model was extracted for each of them, representing the topography of a ground reference point in digital form and therefore usable in computerized processing. The earliest topography of the area studied was provided by NASA which observed 80% of the Earth's surface during the Shuttle Radar Topographic Mission of February 2000. Then, in November 2004, two 2.5 m resolution images of the same area taken at two different angles were acquired especially by the French satellite Spot5 in the framework of an ISIS (CNES) project.
Tropics and subtropics may develop new climates.
A new climate modeling study forecasts the complete disappearance of several existing climates in tropical highlands and regions near the poles, while large swaths of the tropics and subtropics may develop new climates unlike any seen today.
In general, the models show that existing climate zones will shift toward higher latitudes and higher elevations, squeezing out the climates at the extremes--tropical mountaintops and the poles--and leaving room for unfamiliar climes and new ecological niches around the equator.
The work, by researchers at the University of Wisconsin-Madison and the University of Wyoming, appears online in the journal Proceedings of the National Academy of Sciences (PNAS) during the week of March 26. The National Science Foundation (NSF) funded the research.
The most severely affected parts of the world span both heavily populated regions, including the southeastern United States, southeastern Asia, and parts of Africa, and known hotspots of biodiversity, such as the Amazonian rainforest and African and South American mountain ranges.
A new climate modeling study forecasts the complete disappearance of several existing climates in tropical highlands and regions near the poles, while large swaths of the tropics and subtropics may develop new climates unlike any seen today.
In general, the models show that existing climate zones will shift toward higher latitudes and higher elevations, squeezing out the climates at the extremes--tropical mountaintops and the poles--and leaving room for unfamiliar climes and new ecological niches around the equator.
The work, by researchers at the University of Wisconsin-Madison and the University of Wyoming, appears online in the journal Proceedings of the National Academy of Sciences (PNAS) during the week of March 26. The National Science Foundation (NSF) funded the research.
The most severely affected parts of the world span both heavily populated regions, including the southeastern United States, southeastern Asia, and parts of Africa, and known hotspots of biodiversity, such as the Amazonian rainforest and African and South American mountain ranges.
LOS ANGELES - Volatile weather swept through Southern California on Tuesday, delivering downpours, hail, snow, and fierce winds that capsized boats and toppled power lines and trees. Nearly 160,000 customers lost power.
Mount St. Helens may be following the example of Kilauea in Hawaii with magma being replaced from a reservoir beneath the volcano as fast as it emerges as lava at the surface, scientists say.
While the two volcanoes are different in many respects, St. Helens appears to have become an "open system" as its dome building eruption that began in the fall of 2004 continues at a pace that has been unchanged for the past year, said Daniel Dzurisin, a geologist at the U.S. Geological Survey's Cascades Volcano Observatory.
While the two volcanoes are different in many respects, St. Helens appears to have become an "open system" as its dome building eruption that began in the fall of 2004 continues at a pace that has been unchanged for the past year, said Daniel Dzurisin, a geologist at the U.S. Geological Survey's Cascades Volcano Observatory.
Unique climates and the species that inhabit them may disappear from the Earth entirely due to global warming, computer models suggest.
Changes in regions such as the Peruvian Andes, portions of the Himalayas and southern Australia could have a profound impact on indigenous plants and animals, said John W. Williams, assistant professor of geography at the University of Wisconsin, Madison.
The findings are being published in this week's online edition of the Proceedings of the National Academy of Sciences.
Changes in regions such as the Peruvian Andes, portions of the Himalayas and southern Australia could have a profound impact on indigenous plants and animals, said John W. Williams, assistant professor of geography at the University of Wisconsin, Madison.
The findings are being published in this week's online edition of the Proceedings of the National Academy of Sciences.
A team of nearly 50 researchers has determined that an algae bloom known as red tide was responsible for the earlier deaths of animals off the Florida coast.
The research team found that the mysterious deaths of scores of turtles, bottlenose dolphins and manatees back in 2005 off the southwest coast of Florida was likely caused a neurotoxin that was emitted from the red tide, The Washington Post said.
The Working Group on Marine Mammal Unusual Mortality Events study determined that brevetoxin was the likely culprit in the deaths after examining 130 stranded dolphins.
The research team found that the mysterious deaths of scores of turtles, bottlenose dolphins and manatees back in 2005 off the southwest coast of Florida was likely caused a neurotoxin that was emitted from the red tide, The Washington Post said.
The Working Group on Marine Mammal Unusual Mortality Events study determined that brevetoxin was the likely culprit in the deaths after examining 130 stranded dolphins.
Greenland is not known for hurricanes, but the frigid land mass does host some of the strongest - and most mysterious - winds on the planet. Now scientists say the bizarre winds could be linked to weather and climate phenomena far from the icy realm.
After two weeks of flying head-on into hurricane-force winds that whipped recently around the southern tip of Greenland, a group of scientists has a better idea of just how these winds relate to broader weather patterns, global ocean circulation and climate.
Weather experts have only really known about these so-called tip jets for less than a decade, and most of what they knew was from satellite data. The team of scientists, as part of the International Polar Year effort, recently sought to go airborne for a close-up look at the roaring winds.
After two weeks of flying head-on into hurricane-force winds that whipped recently around the southern tip of Greenland, a group of scientists has a better idea of just how these winds relate to broader weather patterns, global ocean circulation and climate.
Weather experts have only really known about these so-called tip jets for less than a decade, and most of what they knew was from satellite data. The team of scientists, as part of the International Polar Year effort, recently sought to go airborne for a close-up look at the roaring winds.
MOGADISHU -- A tsunami hit the coast of the self-autonomous region of Puntland in northeast Somalia, a local official confirmed on Monday, saying three people are missing and presumed dead.
Al Gore likes to present himself as a tribune of science, warning the world of imminent danger. But he is more like an Old Testament prophet, calling on us to bewail our wrongful conduct and to go and sin no more. He starts off with the science. The world's climate, he reports, is getting warmer. This accurate report is, however, not set in historic context. World climate has grown warmer and cooler at various times in history. Climate change is not some unique historic event. It is the way the world works.
Not this time, Gore says. What's different is that climate change is being driven by human activity -- to wit, increasing carbon dioxide emissions. Which means, he says, that we have to sharply reduce those emissions. But what the scientists tell us is that some proportion of climate change is caused by human activity and some proportion by natural causes -- and that they can only estimate what those proportions are. The estimates they have produced have varied sharply. The climate change models that have been developed don't account for events of the recent past, much less predict with precision events in the future.
Not this time, Gore says. What's different is that climate change is being driven by human activity -- to wit, increasing carbon dioxide emissions. Which means, he says, that we have to sharply reduce those emissions. But what the scientists tell us is that some proportion of climate change is caused by human activity and some proportion by natural causes -- and that they can only estimate what those proportions are. The estimates they have produced have varied sharply. The climate change models that have been developed don't account for events of the recent past, much less predict with precision events in the future.
Comment: Climate change is real, and it is a threat, it is just that the reasons behind it are not the ones given by Al Gore and others. To know more check out the article "Climate Change Swindlers and the Political Agenda".