Author
SENAY, GABRIEL - Us Geological Survey (USGS) | |
Gowda, Prasanna | |
BOHMS, S - Us Geological Survey (USGS) | |
Howell, Terry | |
MAREK, THOMAS - Texas Agrilife Research | |
VERDIN, JIM - Us Geological Survey (USGS) |
Submitted to: Meeting Abstract
Publication Type: Abstract Only Publication Acceptance Date: 9/15/2010 Publication Date: 9/28/2010 Citation: Senay, G., Gowda, P., Bohms, S., Howell, T.A., Marek, T.H., Verdin, J.P. 2010. Integrating MODIS and Landsat Data Using the Simplified Surface Energy Balance Approach to Estimate Actual Evapotranspiration at Multiple Scales [abstract]. Remote Sensing and Hydrology Symposium, September 27-30, 2010, Jackson Hole, Wyoming. 2010 CDROM. Interpretive Summary: Technical Abstract: Estimating actual evapotranspiration (ETa) in space and time is critical for developing useful basin water balance models and for monitoring vegetation water use and drought severity analysis. In this study, we combined MODIS and Landsat thermal data using a 'time-limited' stable fractional relationship concept to take advantage of the greater spatial resolution of Landsat data and the greater temporal resolution of MODIS. We validated our approach using data from four weighing lysimeters from Bushland, Texas. Landsat and MODIS images acquired from the 2006 and 2007 growing seasons were processed to produce ET fractions. ET fractions were multiplied by a reference ET collected at a weather station close to the lysimeters. We found a strong correlation (r > 0.9) between modeled ETa and lysimeter measurements of ET. The study shows the potential application of combining MODIS and Landsat data for an effective characterization of ETa in time and space. The findings have implications for setting up a methodology to quantify and monitor vegetation water use at multiple temporal and spatial scales on an operational basis. |