climate change

climate change - Global Climate Change WASHINGTON (CNN:...

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Unformatted text preview: Global Climate Change WASHINGTON (CNN: March 19, 2002) -- A new giant iceberg, “B-22”, is adrift off Antarctica. -- broke off from the mainland into the Ross Sea. -- is about 53 x 40 miles (= size of Rhode Island.) Open Ocean (Ross Sea) B-22 -- One 183 x 22 miles ( = 2x size of Deleware) broke off near there in March of 2000. SO WHAT? WHO CARES? Ice Shelf An unusually high number of icebergs have calved from Antarctica in recent years all around Antarctica. Some researchers speculate there is a possible connection to global warming. Grinnell Glacier in Glacier National Park, Montana; photograph by Carl H. Key, USGS, in 1981. The glacier has been retreating rapidly since the early 1900's. The arrows point to the former extent of the glacier in 1850, 1937, and 1968. Mountain glaciers are excellent monitors of climate change; the worldwide shrinkage of mountain glaciers is thought to be caused by a combination of a temperature increase from the Little Ice Age, which ended in the latter half of the 19th century, and increased greenhouse-gas emissions. Could global warming be man-made through our emission of ‘greenhouse’ gasses? of HOW DOES GREENHOUSE GLOBAL WARMING WORK? HOW --Short wave (ultraviolet) incoming radiation heats earth; -- Long wave (infra red) outgoing radiation blocked by greenhouse gasses. If sea level rises 1 m, who would care? If 1. In Florida: (see lab exercises) 2. Island nations of the IndoPacific (e.g., Marshall Is., Maldives)? Will be inundated. 3. In China? 70 million people would have to be evacuated. 4. In Bangladesh? 32 million evacuated (1/5 of country would disappear). West Gulf Coast Delaware Bay Georgia Antarctic Ice Sheet Antarctic --99% covered in ice up to 2 miles thick East and West Antarctic Ice Sheets Antarctica with the ice removed The East Antarctic Ice Sheet is grounded above sea level. The West Antarctic Ice Sheet (WAIS): Is grounded up to 2000 m below sea level. Which do you think is the more stable and why? (see lab exercise) If the WAIS melts, sea level will rise 20 m. Who cares? In Florida? (see lab CDROM exercise) In Louisiana? ½ the state would be flooded. If all of the ice caps of the world melt, sea levels will rise 72 m (236 ft). 72 ). Who Cares? Who What do the tabloids say? Statue of Liberty What do scientists say? -- Liberty would hardly get her feet wet. -- but, SF’s Golden Gate Bridge will flood (is 220 ft above sea level). What are the long term trends? A scene from the medieval “Little Ice Age” What does history say? --Global temperatures are warmer today than anytime during the past 1000 yrs. Tree ring and instrumented temperature measurements In Antarctica today, scientists say: The Antarctic Peninsula, McMurdo area, and Southern Ocean are warming: Peninsula --up 4-5o C since 1940’s. --Fur and elephant seas are invading from the north. --ditto Gentoo and Chinstrap penguins, displacing Adélies [pix]. --glaciers are retreating. Adélie penguins (S. Wise, 2000) Conflicting science reports, austral summer, 2002: Conflicting Warming trends: Warming --A heat wave at McMurdo and South Pole Station, highest in 2 decades (Antarctic Sun, 1/25/02) --“The Southern Ocean is warming 2x as fast as the global ocean” (S. Gille, Nature, 2/14/02). Cooling trends: Cooling --The “Dry Valleys” near McMurdo Sound have cooled 1 o F in past 35 yrs (NSF, 1/17/02). --The thickness of the West Antarctic Iced Sheet has increased ( Nature, 1/17/02). “A virtual train wreck of information for climate researchers”. virtual Are these merely normal local weather effects? Scientists say: -- “Only long-term, worldwide studies can confirm global warming, its causes and likely effects” -- “More research is needed” What are scientists in the Department of Geology doing? What are scientists in the Geology Department’s Antarctic Marine Geology Research Facility doing? --have initiated “SHALDRIL” to study past ice sheet behavior on the Antarctic margins (beginning 2004) What is George Bush’s plan? --Reduce greenhouse gasses through incentives to business over the next 10 years. --Institute a largely voluntary plan that contrasts sharply with the tougher mandatory Kyoto (Japan) Protocol. --Reject the Kyoto Protocol because some developing countries are exempted from it. What does the opposition say? Sen. Jim Jeffords, Independent (Vermont) on Valentines Day, ‘02): Bush’s plan: -- "Is a love letter to the status quo and the polluting past.“ -- fails to acknowledge that the U.S. is responsible for emitting 25 percent of the world's greenhouse gasses (however, Europe accounts for most of the other 75%, so they aren’t overly enthusiastic about Kyoto either). The debate goes on…… Predicted Future Trends The future according to the Intergovernmental Panel on climate Change (IPPC): (see lab exercise). ...
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This note was uploaded on 10/23/2011 for the course GLY 1000 taught by Professor Parker during the Spring '11 term at FSU.

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