Algal Clues to Antarctic Ice Shelf Ages
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چکیده
1111 Algal Clues to Antarctic Ice Shelf Ages The naturally high variability of sea ice extent in Antarctica and the short duration of instrumental records have combined to obscure any clear record of sea ice coverage change. Curran et al. (p. 1203; see the Perspective by Wolff) present an ice core record of methanesulfonic acid, a species produced by algae living at the edges of ice shelves, which they show is related to the position of the nearby winter-spring sea ice edge observed in satellite data. They use this relation to reconstruct changes in regional sea ice extent during the last 155 years and show that the modern decline began in the 1950s.
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تاریخ انتشار 2003