H11J-06:
A Mechanism for Land-Atmosphere Feedback Involving Planetary Wave Structures
Monday, 15 December 2014: 9:40 AM
Randal D Koster, NASA Goddard Space Flight Center, Global Modeling and Assimilation Office, Greenbelt, MD, United States, Yehui Chang, NASA/GSFC, Greenbelt, MD, United States and Siegfried D Schubert, Global Modeling and Assimilation Office, Greenbelt, MD, United States
Abstract:
While the ability of land surface conditions to influence the atmosphere has been demonstrated in various modeling and observational studies, the precise mechanisms by which land-atmosphere feedback occurs are still largely unknown – particularly the mechanisms that allow land moisture state in one region to affect atmospheric conditions in another region, perhaps a thousand kilometers away. Such remote impacts are examined here in the context of atmospheric general circulation model (AGCM) simulations, leading to the identification of one potential mechanism: the phase-locking and amplification of a planetary wave through the imposition of a spatial pattern of soil moisture at the land surface. This mechanism, shown here to be relevant in the AGCM, apparently also operates in nature, as suggested by supporting evidence found in reanalysis data.
