TY - JOUR
T1 - A model of the coupled dynamics of climate, vegetation and terrestrial ecosystem biogeochemistry for regional applications
AU - Smith, Benjamin
AU - Samuelsson, Patrick
AU - Wramneby, Anna
AU - Rummukainen, Markku
PY - 2011
Y1 - 2011
N2 - Regional climate models (RCMs) primarily represent physical components of the climate system, omitting vegetation dynamics, ecosystem biogeochemistry and their associated feedbacks. To account for such feedbacks, we implemented a novel plant individual-based vegetation dynamics-ecosystem biogeochemistry scheme within the RCA3 RCM. Variations in leaf area index (LAI) of seven plant functional type (PFTs) in response to physical forcing and evolving vegetation state feed back to climate via adjustments in surface energy fluxes and surface properties. In an ERA-40- driven simulation over Europe, the model reproduces the recent past climate with comparable accuracy to the standard RCM. Large-scale patterns of LAI, net primary production and vegetation composition were comparable with observations, although winter LAI was systematically overestimated compared to satellite estimates. Analysis of the ERA-40 simulation and an A1B climate-change simulation revealed considerable covariation among dynamic variables of the physical climate and vegetation. At a Mediterranean site, periodic soil water limitation led to fluctuations in leaf cover and a likely positive feedback to near-surface temperature. At an alpine site, rising temperatures led to forest advance onto tundra areas, reducing albedo and effecting a likely positive feedback on temperature. Climate–vegetation coupling was less pronounced but still apparent at intermediate temperate and boreal sites.
AB - Regional climate models (RCMs) primarily represent physical components of the climate system, omitting vegetation dynamics, ecosystem biogeochemistry and their associated feedbacks. To account for such feedbacks, we implemented a novel plant individual-based vegetation dynamics-ecosystem biogeochemistry scheme within the RCA3 RCM. Variations in leaf area index (LAI) of seven plant functional type (PFTs) in response to physical forcing and evolving vegetation state feed back to climate via adjustments in surface energy fluxes and surface properties. In an ERA-40- driven simulation over Europe, the model reproduces the recent past climate with comparable accuracy to the standard RCM. Large-scale patterns of LAI, net primary production and vegetation composition were comparable with observations, although winter LAI was systematically overestimated compared to satellite estimates. Analysis of the ERA-40 simulation and an A1B climate-change simulation revealed considerable covariation among dynamic variables of the physical climate and vegetation. At a Mediterranean site, periodic soil water limitation led to fluctuations in leaf cover and a likely positive feedback to near-surface temperature. At an alpine site, rising temperatures led to forest advance onto tundra areas, reducing albedo and effecting a likely positive feedback on temperature. Climate–vegetation coupling was less pronounced but still apparent at intermediate temperate and boreal sites.
KW - carbon cycle (biogeochemistry)
KW - climatic changes
KW - computer simulation
KW - vegetation dynamics
UR - http://handle.westernsydney.edu.au:8081/1959.7/uws:48426
U2 - 10.1111/j.1600-0870.2010.00477.x
DO - 10.1111/j.1600-0870.2010.00477.x
M3 - Article
SN - 0280-6495
VL - 63
SP - 87
EP - 106
JO - Tellus Series A: Dynamic Meteorology and Oceanography
JF - Tellus Series A: Dynamic Meteorology and Oceanography
IS - 1
ER -