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Can Melting Antarctic Permafrost Help Push Global Warming?

How did ancient global warming occur and are we heading that way again? First, let’s just state the obvious and not carp on is it or isn’t it true. Our Earth goes through its own life-cycles, and it does grow warm and cool depending on so many variables that we, humans, can’t yet contemplate. Our scientists do the best they can with the information they can “see”, but there are so many other factors that play a part in these Earth changes. One example is the tilt of our Earth. Every twenty-thousand years or so, the earth wobbles in its orbit; this wobble tilts the Earth just right and wham! The Sahara Desert is now a tropical oasis. I was so excited when I first learned this, but we have at least another fifteen thousand years to go before the next ‘wobble’.

So is there a global warming. You bet there is. But, I do not believe it is caused just by humans, although we may play a small role in it, I honestly think we are entering one of Mother Earth’s changes. Such an event took place some fifty-five million years ago. During that change the world abruptly warmed by 5 degrees Celsius and turned the oceans acidic.

But how? That is the question scientists have been working on for over fourteen years, and may finally have an answer. The green-house gases needed may have gushed into the atmosphere from thawing permafrost in an ice-free Antarctica. Although this is still a theory, it is possible that extremely large stores of methane hydrates, created by rotted plants stored in coal, the mud in oceans and lakes and in soil can freeze and become huge storage vaults. As the permafrost melts, the gas is released.

So as we thaw permafrost today, it is releasing these greenhouse gasses back into the atmosphere. Once the tipping point is met and substantial melting occurs you can have a sudden explosion of methane gas gushing into the atmosphere.

The problem with this theory, just like any other, is how do you prove it.

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Posted by on July 1, 2012 in Earth Changes, Global Warming, Science

 

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Is Global Warming To Blame?

Pine Island Glacier

In mid-October 2011, NASA scientists working in Antarctica discovered a massive crack across the Pine Island Glacier, a major ice stream that drains the West Antarctic Ice Sheet. Extending for 19 miles (30 kilometers), the crack was 260 feet (80 meters) wide and 195 feet (60 meters) deep. Eventually, the crack will extend all the way across the glacier, and calve a giant iceberg that will cover about 350 square miles (900 square kilometers). This image from the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) instrument on NAS’s Terra spacecraft was acquired Nov. 13, 2011, and covers an area of 27 by 32 miles (44 by 52 kilometers), and is located near 74.9 degrees south latitude, 101.1 degrees west longitude.

Image Credit: NASA/GSFC/METI/ERSDAC/JAROS, and U.S./Japan ASTER Science Team

 
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Posted by on January 31, 2012 in Earth Changes, Global Warming, NASA, Photo, Science

 

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Arctic Sea Ice Continues Decline

Last month the extent of sea ice covering the Arctic Ocean declined to the second-lowest extent on record. Satellite data from NASA and the NASA-supported National Snow and Ice Data Center (NSIDC) at the University of Colorado in Boulder showed that the summertime sea ice cover narrowly avoided a new record low.

The Arctic ice cap grows each winter as the sun sets for several months and shrinks each summer as the sun rises higher in the northern sky. Each year the Arctic sea ice reaches its annual minimum extent in September. It hit a record low in 2007.

The near-record ice-melt followed higher-than-average summer temperatures, but without the unusual weather conditions that contributed to the extreme melt of 2007. “Atmospheric and oceanic conditions were not as conducive to ice loss this year, but the melt still neared 2007 levels,” said NSIDC scientist Walt Meier. “This probably reflects loss of multiyear ice in the Beaufort and Chukchi seas as well as other factors that are making the ice more vulnerable.”

Joey Comiso, senior scientist at NASA’s Goddard Space Flight Center in Greenbelt, Md., said the continued low minimum sea ice levels fits into the large-scale decline pattern that scientists have watched unfold over the past three decades.

“The sea ice is not only declining, the pace of the decline is becoming more drastic,” Comiso said. “The older, thicker ice is declining faster than the rest, making for a more vulnerable perennial ice cover.”

While the sea ice extent did not dip below the 2007 record, the sea ice area as measured by the microwave radiometer on NASA’s Aqua satellite did drop slightly lower than 2007 levels for about 10 days in early September, Comiso said. Sea ice “area” differs from extent in that it equals the actual surface area covered by ice, while extent includes any area where ice covers at least 15 percent of the ocean.

Arctic sea ice extent on Sept. 9, the lowest point this year, was 4.33 million square kilometers (1.67 million square miles). Averaged over the month of September, ice extent was 4.61 million square kilometers (1.78 million square miles). This places 2011 as the second lowest ice extent both for the daily minimum extent and the monthly average. Ice extent was 2.43 million square kilometers (938,000 square miles) below the 1979 to 2000 average.

This summer’s low ice extent continued the downward trend seen over the last 30 years, which scientists attribute largely to warming temperatures caused by climate change. Data show that Arctic sea ice has been declining both in extent and thickness. Since 1979, September Arctic sea ice extent has declined by 12 percent per decade.

“The oldest and thickest ice in the Arctic continues to decline, especially in the Beaufort Sea and the Canada Basin,” NSIDC scientist Julienne Stroeve said. “This appears to be an important driver for the low sea ice conditions over the past few summers.”
Climate models have suggested that the Arctic could lose almost all of its summer ice cover by 2100, but in recent years, ice extent has declined faster than the models predicted.

NASA monitors and studies changing sea ice conditions in both the Arctic and Antarctic with a variety of spaceborne and airborne research capabilities. This month NASA resumes Operation IceBridge, a multi-year series of flights over sea ice and ice sheets at both poles. This fall’s campaign will be based out of Punta Arenas, Chile, and make flights over Antarctica . NASA also continues work toward launching ICESat-2 in 2016, which will continue its predecessor’s crucial laser altimetry observations of ice cover from space.

 

 

 

 

 
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Posted by on October 9, 2011 in Earth Changes, Global Warming, NASA, Science

 

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