HR: 1340h
AN: B33B-1202 [Abstracts]
TI: Joint Statistical and Dynamical Assessment of Simulated Vegetation Feedbacks on Climate Over the Boreal Forests
AU: Notaro, M
EM: mnotaro@wisc.edu
AF: Center for Climatic Research, UW Madison, 1225 West Dayton Street, Room 1103,
Madison, Wi 53076, United States
AU: * Liu, Z
EM: zliu3@wisc.edu
AF: Center for Climatic Research, UW Madison, 1225 West Dayton Street, Room 1103,
Madison, Wi 53076, United States
AB:
Vegetation feedbacks over Asiatic Russia are assessed through a combined statistical and dynamical approach
in a fully coupled atmosphere-ocean-land model, FOAM-LPJ. The dynamical assessment is comprised of initial
value ensemble experiments in which the forest cover fraction is initially reduced over Asiatic Russia, replaced by
grass cover, and then the climatic response is determined. The statistical feedback approach, adopted from
previous studies of ocean-atmosphere interactions, is applied to compute the feedback of forest cover on
subsequent temperature and precipitation in the control simulation. Both methodologies indicate a year-round
positive feedback on temperature and precipitation, strongest in spring and moderately substantial in summer.
Reduced boreal forest cover enhances the surface albedo, leading to an extended snow season, lower air
temperatures, increased atmospheric stability, and enhanced low cloud cover. Changes in the hydrological cycle
include diminished transpiration and moisture recycling, supporting a reduction in precipitation. The close
agreement in sign and magnitude between the statistical and dynamical feedback assessments testifies to the
reliability of the statistical approach. This study supports the previous finding of a strong positive vegetation
feedback on air temperature over Asiatic Russia in the observational record.
DE: 1631 Land/atmosphere interactions (1218, 1843, 3322)
DE: 1843 Land/atmosphere interactions (1218, 1631, 3322)
DE: 3322 Land/atmosphere interactions (1218, 1631, 1843)
SC: Biogeosciences [B]
MN: 2007 Fall Meeting