MŸller, Omar V. , CEVARCAM - Universidad Nacional del
Litoral, Argentina, Ernesto H. Berbery, ESSIC - University of Maryland, USA,
and Domingo Alcaraz-Segura,
Departamento de Biolog’a Vegetal y Ecolog’a, Universidad de Almer’a, Spain
Land surface processes
vary from energy and water exchange with the atmosphere on short time scales to
changes in soil moisture, vegetation structure and phenology on longer
timescales. However, WRF model represents vegetation with land cover types
fixed in time. Hence, they are insensitive to any vegetation variability.
In order to include
biosphere processes and their effects over the atmosphere, we examine the
advantages of using Ecosystem Functional Types (EFTs) as a replacement of
conventional land cover types. EFTs are groups of ecosystems that share
functional characteristics in relation to the exchanges of matter and energy
between the biota and the physical environment. EFTs are defined on a yearly
basis, therefore, they can reproduce vegetation changes resulting from either
land use or natural changes.
Long-term simulations
with conventional land cover representation were compared with simulations
using EFTs as lower boundary conditions during the drought of 2008 in
southestern South America. The results show the model sensitivity to vegetation
variability, reducing the precipitation bias over the drought region and
another region of large precipitation to the north. This suggests that a better
representation of surface processes could enhance the system predictability.