Three of the four models indicated (in accordance with O 2 evidence) that the tropics were approximately neutral while a net sink existed in ecosystems north of the tropics. ![]() ![]() During the 1980s the simulations indicate that terrestrial ecosystems stored between 0.3 and 1.5 Pg C yr -1, which is within the uncertainty of analysis based on CO 2 and O 2 budgets. After 1958, all analyses indicate a net uptake of carbon by terrestrial ecosystems, primarily because of the physiological effects of rapidly rising atmospheric CO 2. Up to 1958, three of four analyses indicated a net release of carbon from terrestrial ecosystems to the atmosphere caused by cropland establishment. Over the long-term (1920-1992), the simulations yielded a time history of terrestrial uptake that is consistent (within the uncertainty with a long-term analysis based on ice core and atmospheric CO 2 data. The concurrent effects of increasing atmospheric CO 2 concentration, climate variability, and cropland establishment and abandonment on terrestrial carbon storage between 19 were assessed using a standard simulation protocol with four process-based terrestrial biosphere models.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |