Missing radioactive signals in Himalayan ice cores spells danger for part of AsiaNovember 19th, 2008 - 1:06 pm ICT by ANI
Washington, Nov 19 (ANI): Glaciologists have been unable to find the expected radioactive signals in the latest core they drilled from a Himalayan ice field, which suggests absence of accumulation of ice in the region, that could impact water resources for the people living in that part of Asia.
The researchers determined that the missing markers of radiation, remnants from atomic bomb tests a half-century ago, foretell much greater threat to the half-billion or more people living downstream of that vast mountain range.
It may mean that future water supplies could fall far short of whats needed to keep that population alive.
Researchers from the Byrd Polar Research Center explain that levels of tritium, beta radioactivity emitters like strontium and cesium, and an isotope of chlorine are absent in all three cores taken from the Naimonanyi glacier 19,849 feet (6,050 meters) high on the southern margin of the Tibetan Plateau.
Weve drilled 13 cores over the years from these high-mountain regions and found these signals in all but one this one, explained Lonnie Thompson, University Distinguished Professor of Earth Sciences at Ohio State University.
The absence of radioactive signals in the top portion of these cores is a critical problem for determining the age of the ice in the cores.
We rely on these time markers to date the upper part of the ice cores and without them, extracting the climate history they preserve becomes more challenging, Thompson said.
Tritium, an isotope of hydrogen, and chlorine-36 were also both absent from the Naimonanyi cores, according to Natalie Kehrwald, a doctoral student at Ohio State and lead author on the paper.
They were able, however, to find a small amount of a lead isotope, lead-210, which allowed them to date the top of the core.
We were able to get a date of approximately 1944 A.D., and that, coupled with the other missing signals, means that no new ice has accumulated on the surface of the glacier since 1944, Kehrwald said.
Thompson is worried about the possibility that other high-altitude glaciers in the region, like Naimonanyi, are no longer accumulating ice and the impact that could have on water resources for the people living in these regions.
According to Thompson, whats happening to the Naimonanyi glacier may be happening to many other high-altitude glaciers around the world.
I think that this has tremendous implications for future water supplies in the Andes, as well as the Himalayas, and for people living in those regions, he said.
When you think about the millions of people over there who depend on the water locked in that ice, if they dont have it available in the future, that will be a serious problem, he added. (ANI)
Tags: atomic bomb tests, beta radioactivity, byrd polar research, byrd polar research center, cesium, climate history, critical problem, earth sciences, emitters, ice cores, isotope, lonnie thompson, mountain regions, ohio state university, polar research center, southern margin, strontium, tibetan plateau, time markers, tritium