HR: 09:45h
AN: B21C-08    [Abstracts]
TI: Modeling impact of permafrost dynamics on carbon dioxide and methane cycling in northern high latitudes
AU: * Zhuang, Q
EM: qzhuang@purdue.edu
AF: Departments of Earth & Atmospheric Sciences and Agronomy, CIVL 550 Stadium Mall Drive, West Lafayette, IN 47907, United States
AB: Over the last several centuries, permafrost conditions in northern high latitudes have changed, and are likely to continue changing. A growing body of evidence indicates that the terrestrial ecosystems in the region are undergoing substantial changes associated with the warming that has been occurring during recent decades. The fate of the large amount of carbon stored in the region is uncertain under these changes. In this study, a process-based biogeochemistry model, coupled with a permafrost model, is used to estimate the budget of carbon dioxide and methane of the region for current climate conditions and for future scenarios by considering effects of permafrost dynamics and fire disturbances. The simulations indicate that currently the region is a net source of carbon to the atmosphere. Throughout this century, the region will most likely continue as a net source of carbon due to permafrost thawing and fire disturbances. In particular, the methane emissions will more than double the amount of current emissions. However, the coupled carbon and climate model simulations show that these emissions will exert relatively small radiative forcing on global climate system compared to large amounts of anthropogenic emissions. The further analysis suggests that the complex interactions of permafrost, fire, and topographical and hydrological changes should be considered in the future quantification of these gases budget for the region.
DE: 0414 Biogeochemical cycles, processes, and modeling (0412, 0793, 1615, 4805, 4912)
DE: 0426 Biosphere/atmosphere interactions (0315)
DE: 0428 Carbon cycling (4806)
DE: 0429 Climate dynamics (1620)
DE: 0439 Ecosystems, structure and dynamics (4815)
SC: Biogeosciences [B]
MN: 2007 Fall Meeting