Glaciers And Ice Caps Dominate for the Sea Level Rise This Century.By the scientists at the National Center for Atmospheric Research (NCAR) and the University of Arizona, by 2100 the Arctic summers may be as warm as they were nearly 130,000 years ago when sea levels rose to 20 feet (6 meters) higher than they are today!! For the year 2025 the range might become from 5
to 21 inches above current sea level, while estimates of the rise by 2100 range from 2 to ll
feet. The glaciers and ice caps are currently contributing about 60 percent of the world’s ice to the oceans and it is well known now that Greenland is nowadays contributing about 28 percent of the total global sea rise from ice loss!
“One reason for this study is the widely held view that the Greenland and Antarctic ice sheets will be the principal causes of sea-level rise,” said Meier, former INSTAAR director and professor in geological sciences.
Using satellites to measure changes in elevation, Curt Davis, MU professor of electrical and computer engineering, and his team of researchers observed 7.1 million kilometers of the ice sheet for the period from 1992 to 2003. For this period they discovered that the ice sheet’s interior was gaining mass by about 45 billion tons per year, which was enough to slow sea level rise by .12 millimeters per year. NASA’s Cryospheric Processes Program and the National Science Foundation’s Antarctic Glaciology Program, suggests that increased precipitation was somehow or likely cause of the gain.
“While this is a dynamic, complex process and does not seem to be a direct result of climate warming, it is likely that climate acts as a trigger to set off this dramatic response,” said Anderson, also an INSTAAR researcher. More information on this global warming and climate changing topic here
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August 11th, 2007 at 6:12 am
As our teacher said, Stratigraphic and sedimentological data are presented from a region likely to directly record the evolution of the East Antarctic ice sheet. (We was up on this topic for one semester!!)Along the western margin of the Lambert graben, which now drains ~1 x 106 km2 or one-eighth of the total area of the East Antarctic ice sheet, extensive remnants of Cenozoic glaciomarine fjordal sediment, known as the Pagodroma Group, are preserved as far as several hundred kilometers inland from the open coast. (tell me,is it real?!?)The sediments resemble those produced by tidewater glaciers in the Arctic, rather than those of modern Antarctica. Four separate formations of the Pagodroma Group, spanning the interval from early Miocene (or older) to Pliocene or early Pleistocene are preserved; the oldest and highest crop out at nearly 1500 m above sea level. Each formation was deposited in close proximity to an ice margin grounded on the fjord bottom during major recessional phases of the Lambert Glacier. Underlying each formation is a glacially cut erosion surface. Each surface records a separate stage of fjord excavation when ice expanded onto the continental shelf in Prydz Bay. Evidence from offshore drilling in Prydz Bay and these data indicate fluctuations of the Lambert Glacier terminus in excess of 500 km in Neogene time, thereby reflecting large changes in the volume of the ice sheet. Depositional episodes were succeeded by phases of uplift totalling more than 1500 m.
August 11th, 2007 at 6:16 am
These are among the surprising results of a study of ice-mass changes from 1992-2002, which just appeared in the Journal of Glaciology. The study, which went counter to many expert estimates, is based on the most precise satellite altimetry data ever gathered, using the European Remote-sensing Satellites ERS-1 and 2, and other observations.Check it out!
August 11th, 2007 at 6:24 am
Yeah, in the 19th Century, geologists had noted a wide array of observations which indicated that the Northern Hemisphere had passed through one or more cycles of glaciation. As i know, these obervations were correlated over different parts of the Earth, it appeared that a sheet of ice had moved down from Greenland and the Polar region, burying the northern parts of North America and Eurasia in ice from one to two miles thick. About 13,000 years ago, it was near the star Vega in the constellation Lyra. The term “precession of the equinox” comes from the fact that ancient astronomers observed a gradual change in the alignment of the Sun against the background of stars, as it rose on the first day of Spring (vernal equinox) and that’s just another point of view or start line of this studying.. Greetings to your team.
-r-
August 11th, 2007 at 6:37 am
I have found these days report where was shown that “the Greenland ice sheet is thinning at the margins (-42 ± 2 Gt a-1 below the equilibrium-line altitude (ELA)) and growing inland (+53 ± 2 Gt a-1 above the ELA) with a small overall mass gain (+11 ± 3 Gt a-1; -0.03 mm a-1 SLE (sea-level equivalent)).” Likewise, they say that “the ice sheet in West Antarctica (WA) is losing mass (-47 ± 4 Gt a-1) and the ice sheet in East Antarctica (EA) shows a small mass gain (+16 ± 11 Gt a-1) for a combined net change of -31 ± 12 Gt a-1 (+0.08 mm a-1 SLE).” Hence, they report that “the contribution of the three ice sheets to sea level is +0.05 ± 0.03 mm a-1.” Furthermore, although not impacting sea level, they note that “the Antarctic ice shelves show corresponding mass changes of -95 ± 11 GT a-1 in WA and +142 ± 10 Gt a-1 in EA.” Do you know what it means,guys?!!
Only hopes for higher public interest anxiety overtaking the rising climate changes should keep our chances in real proportions!