通過氣候模擬分析,，研究人員指出,，在21世紀(jì)的進(jìn)程中，格陵蘭島和南極州冰原周圍的海洋亞表面溫度將分別升高 1.7℃~2℃和0.5℃~0.6℃,，這種變暖趨向?qū)?dǎo)致冰原的大量融化,、海平面的升高，新成果發(fā)表在7月在線出版的《自然—地球科學(xué)》期刊上,。
Jianjun Yin和同事利用19個基于中等排放水平的全新氣候模式,，模擬了21世紀(jì)的氣候變化。他們發(fā)現(xiàn)在海洋下200米~500米深處之間,，環(huán)繞兩個冰川的海洋溫度的變暖程度將大大超過目前的溫度變化,。
他們的模擬結(jié)果顯示，格陵蘭島周圍海洋的變暖程度將是全球平均水平的兩倍,，而南極洲附近海洋變暖程度只有全球平均水平的一半,。(生物谷 Bioon.com)
doi:10.1038/ngeo1189
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Different magnitudes of projected subsurface ocean warming around Greenland and Antarctica
Jianjun Yin; Jonathan T. Overpeck; Stephen M. Griffies; Aixue Hu; Joellen L. Russell; Ronald J. Stouffer
The observed acceleration of outlet glaciers and ice flows in Greenland and Antarctica is closely linked to ocean warming, especially in the subsurface layer1, 2, 3, 4, 5. Accurate projections of ice-sheet dynamics and global sea-level rise therefore require information of future ocean warming in the vicinity of the large ice sheets. Here we use a set of 19 state-of-the-art climate models to quantify this ocean warming in the next two centuries. We find that in response to a mid-range increase in atmospheric greenhouse-gas concentrations, the subsurface oceans surrounding the two polar ice sheets at depths of 200–500 m warm substantially compared with the observed changes thus far6, 7, 8. Model projections suggest that over the course of the twenty-first century, the maximum ocean warming around Greenland will be almost double the global mean, with a magnitude of 1.7–2.0 °C. By contrast, ocean warming around Antarctica will be only about half as large as global mean warming, with a magnitude of 0.5–0.6 °C. A more detailed evaluation indicates that ocean warming is controlled by different mechanisms around Greenland and Antarctica. We conclude that projected subsurface ocean warming could drive significant increases in ice-mass loss, and heighten the risk of future large sea-level rise.
