HR: 0800h
AN: H31E-0696 [Abstracts]
TI: Study of vegetation effects on land-atmospheric interaction using the Weather Research and Forecasting model and MODIS data
AU: Hong, S
EM: bryan.s.hong@gmail.com
AF: University of South Carolina, Department of Geologicial Sciences, Columbia, SC 29201,
United States
AU: * Lakshmi, V
EM: vlakshmi@geol.sc.edu
AF: University of South Carolina, Department of Geologicial Sciences, Columbia, SC 29201,
United States
AU: Small, E E
EM: Eric.Small@colorado.edu
AF: University of Colorado, Department of Geological Sciences, Boulder, CO 80309, United
States
AU: Chen, F
EM: feichen@ncar.ucar.edu
AF: National Center for Atmospheric Research, Research Application Lab, Boulder, CO 80307,
United States
AB:
Land-atmospheric interactions have been an important issue in weather and climate modeling.
Evapotranspiration (ET) is a major feedback from the land surface to the atmosphere and we analyze land
surface processes simulated from the Noah (National Centers for Environmental Prediction – Oregon State
University – Air Force - National Weather Service Office of Hydrology) Land Surface Model (Noah LSM) coupled
with a generic mesoscale model in the Weather Research and Forecasting (WRF) framework. The International
H2O project (IHOP) area is the study domain chosen due to the availability of ground observations. Soil moisture
and skin surface temperature (TSK) initializations are tested for the model improvement through the comparison
to the ground observation data from the 9 Integrated Surface Flux Facilities (ISFF) over the IHOP area. Three days
are selected during the study period - DRY1, WET, and DRY2. The relationship between TSK and Normalized
Difference Vegetation Indices (NDVI) is assessed to investigate biophysical effects on ET and the model
sensitivity to different model initialization. This study indicates that the soil moisture initialization improves soil
moisture simulations but causes overestimations of ET in vegetated areas. We further test the parameterization
of vegetation fraction derived from daily or semi-monthly Moderate Resolution Imaging Spectroradiometer
(MODIS) NDVI to improve the model sensitivity to soil moisture variations. In addition, we evaluate the applicability
of vegetation water content which is not involved in the surface flux algorithm but substantially influential on ET.
DE: 0315 Biosphere/atmosphere interactions (0426, 1610)
DE: 1843 Land/atmosphere interactions (1218, 1631, 3322)
DE: 1846 Model calibration (3333)
DE: 1855 Remote sensing (1640)
SC: Hydrology [H]
MN: 2007 Fall Meeting