Location: Soil and Water Management Research
Project Number: 3090-13000-014-29
Start Date: Feb 15, 2013
End Date: Jul 31, 2014
Surface Energy Balance System (SEBS) will be used for mapping ET with a daily, monthly, and seasonal time-step with both MODIS (250-1000 m) and Landsat 5 TM (30-120 m) satellite data. Remote sensing database will be screened to remove images with cloud cover. We will use MODIS and Landsat TM/ETM+ data acquired during 2000-2009 for estimating daily, monthly, and seasonal ET maps. MODIS images will be used for mapping ET for the entire study area. However, the Landsat TM data will be used for locations where high resolution ET data is needed for site-specific full life cycle analysis. We will use weather and reference ET data from the Texas High Plains ET (TXHPET) network for the Texas High Plains, University of Oklahoma's Mesonet data for Oklahoma. Selection of the reference ET stations will be based on the quality of the data and locations. Two Source Model (TSM) model will be applied on the Landsat data to derive evaporation and transpiration maps separately. Since ground observations (lysimetric measurements) of ET for assessing the accuracy are available only for the Texas High Plains, vigorous accuracy assessment of ET maps will be done for that region only. For Oklahoma and Kansas regions of the Southern High Plains, SEBS-based ET maps as observations in evaluating TSM-based evaporation and transpiration maps. MODIS-based ET maps will be evaluated using the Landsat-based ET maps as high-resolution Landsat data most likely to yield relatively accurate ET maps. SEBS and TSM will be evaluated by comparing daily ET against lysimetric measurements.