LAND SURFACE PROCESSES DEVELOPED OVER HETEROGENEOUS LANDSCAPES ARE FUNDAMENTAL TO ATMOSPHERIC CONDITIONS. HOWEVER DUE TO THEIR HIGH COMPLEXITY LAND SURFACE PROCESSES ARE NOT WELL REPRESENTED IN MOST COUPLED LAND-ATMOSPHERE MODELING SYSTEMS. THIS BECOMES AN ISSUE FOR ATMOSPHERIC MODELING OVER AREAS WITH HIGHLY VARIABLE LAND SURFACE CONDITIONS. ONE OF THE EXAMPLES IS THE NORTH AMERICANMONSOON (NAM) REGION OVER THE SOUTHWEST US AND NORTHERN MEXICO. PREVIOUS HYDROLOGIC MODELING EFFORTS OVER A MOUNTAINOUS BASIN IN THE NAM REGION SHOW THAT SPATIAL PATTERNS OF LAND SURFACE TEMPERATURE VARY DRAMATICALLY FROM LATE-SPRING TO LATE-SUMMER WHICH COULD POTENTIALLY ALTER MESOSCALE THERMAL CIRCULATIONS AND RAINFALL GENERATION. INSPIRED BY THIS HYDROLOGIC MODELING STUDY WE ARE INTERESTED IN EXPLORING LAND SURFACE PATTERNS AT REGIONAL SCALES AND ASSESSING THEIR IMPACT ON LAND-ATMOSPHERIC INTERACTIONS THROUGH NUMERICAL MODELING AND SPATIAL ANALYSES OF REMOTE SENSING PRODUCTS. THE MODELING TOOL WE WILL TEST IS WRF-NOAH-MP A FULLY COUPLED HYDROLOGIC AND ATMOSPHERIC MODELING SYSTEM DEVELOPED BY THE NATIONAL CENTER FOR ATMOSPHERIC RESEARCH. THE MODEL DOMAIN IS LOCATED IN THE SIERRA MADRE OCCIDENTAL REGION OF NORTHERN MEXICO WHERE EXISTING INSTRUMENTATION FACILITIES AND DATA COLLECTION EFFORTS WILL BE USED FOR MODEL EVALUATION. TO TEST THE LAND SURFACE MODEL PERFORMANCE OF WRF-NOAH-MP WE WILL CONDUCT A MODEL INTERCOMPARISON EXPERIMENT BETWEEN THE LAND SURFACE MODEL NOAH-MP AND A HIGH-RESOLUTION HYDROLOGIC MODEL TRIBS WHICH HAS BEEN APPLIED AND INTENSIVELY VERIFIED OVER OUR STUDY REGION. MEANWHILE BOTH LAND SURFACE MODELS WILL BE TESTED AGAINST SITE OBSERVATIONS AND REMOTELY SENSED PRODUCTS (E.G. MODIS AND ASTER LAND SURFACE TEMPERATURE). ONCE CONFIDENCE IN THE NOAH-MP SIMULATION IS ACHIEVED WE WILL USE IT TO EXPLORE THE SEASONAL EVOLUTION OF HYDROLOGIC CONDITIONS WITH RESPECT TO TERRAIN SOIL AND VEGETATION AT THE REGIONAL SCALE. TO TEST THE IMPACT OF SEASONAL VEGETATION GREENING ONE OF THE CHARACTERISTIC PHENOMENA IN THE NAM REGION SIMULATIONS WITH AND WITHOUT REMOTELY-SENSED VEGETATION PARAMETERS WILL BE COMPARED. TO QUANTIFY THE IMPACT OF LAND SURFACE PROCESSES ON THE ATMOSPHERE WE WILL THEN UTILIZE THE FULLY-COUPLED VERSION OF WRF-NOAH-MP. TIME-VARYING VEGETATION PARAMETERS DERIVED FROM REMOTE SENSING PRODUCTS WILL BE INGESTED TO CAPTURE THE SEASONAL VEGETATION EVOLUTION. SENSITIVITY ANALYSES WITH VARYING LAND SURFACE SPECIFICATIONS WILL BE CONDUCTED TO QUANTIFY THE PATTERNS AND MAGNITUDE OF SURFACE CONDITIONS NECESSARY TO ENHANCE/SUPPRESS MOUNTAINVALLEY CIRCULATIONS AND RAINFALL GENERATION. MEANWHILE THE IMPORTANCE OF VEGETATION DATA INGESTION FOR LAND SURFACE MODELING AND NUMERICAL WEATHER PREDICTION (NWP) WILL BE IDENTIFIED. SUBSEQUENTLY FULLY-COUPLED SIMULATIONS WILL BE USED FOR TESTING THE ABILITY OFWRF-NOAH-MP TO CAPTURE INTRASEASONAL RAINFALL GENERATION AND HYDROLOGIC RESPONSES OVER COMPLEX TERRAIN. THROUGH THE PROPOSED WORK WE EXPECT THAT ENHANCED LAND SURFACE PHYSICS (E.G. TERRAIN ROUTING OF SURFACE AND SUBSURFACE FLOW TERRAIN EFFECTS ON RADIATION AND LAND SURFACE TEMPERATURE TIME-VARYING VEGETATION COVER) IN WRF-NOAH-MP WILL YIELD IMPROVED PREDICTION AS COMPARED TO OPERATIONAL MODEL FORECASTS AND REANALYSIS-DERIVED FIELDS. SINCE WRF-NOAH-MP IS A RECENTLY-RELEASED COMMUNITY FRAMEWORK AND HAS NOT BEEN BROADLY TESTED THIS PROPOSED WORK WILL DIRECTLY BENEFIT THE ATMOSPHERIC AND HYDROLOGIC SCIENCE COMMUNITIES. THE DYNAMIC VEGETATION INPUTS WILL PROMOTE THE APPLICATION OF MODIS DATA IN LAND-ATMOSPHERE INTERACTION STUDIES AND NWP. THE EVALUATION OF MODEL-SIMULATED LAND SURFACE CONDITIONS AGAINST OBSERVATIONS (IN-SITU AND REMOTELY-SENSED) WILL PREPARE FUTURE DATA ASSIMILATION EFFORTS FOR NWP MODELS RELATED TO VEGETATION AND LAND SURFACE TEMPERATURE. IN ADDITION THE PROPOSED MODELING FRAMEWORK AND APPLICATIONS ARE POTENTIALLY USEFUL FOR COMPARISON TO NEW REMOTE SENSING MISSIONS AIMED AT PRECIPITATION AND SOIL MOISTURE.