|NIETO, H. - Collaborator|
|SONG, L. - Collaborator|
|Kustas, William - Bill|
|PRUEGER, J.H. - US Department Of Agriculture (USDA)|
|GONZALEZ-TEJADA, P. - Collaborator|
|TORRES, A. - Collaborator|
|MCKEE, M. - Collaborator|
Submitted to: BARC Poster Day
Publication Type: Abstract Only
Publication Acceptance Date: 5/15/2015
Publication Date: 5/29/2015
Citation: Nieto, H., Song, L., Kustas, W.P., Alfieri, J.G., Prueger, J., Gonzalez-Tejada, P., Torres, A., Mckee, M. 2015. Estimation of water and energy fluxes over complex landscapes. Two Source Energy Balance modelling using very high resolution thermal and optical imagery in vineyards and wooded rangelands. BARC Poster Day.
Technical Abstract: Modelling the water and energy balance at the land surface is a crucial task for many applications related to crop production, water resources management, climate change studies, weather forecasting, and natural hazards assessment. To improve the modelling of evapotranspiration (ET) over structurally heterogeneous landscapes such as vineyards and open wooded rangelands we will make use of remote sensing data at very high spatial resolution (less than 1m) acquired from an Unmanned Aerial Vehicle (UAV) and manned aircraft over sites in Spain and California. A remote sensing-based ET model that combines multi-angular with multi-temporal visible/near-infrared and thermal-infrared measurements, based on the flexibility of airborne data in flying at different times of the day and the analysis of overlapping imagery, will be described. The main hypothesis of this approach is that by combining multi-angular with multi-temporal observations, it is possible to obtain accurate estimates of soil evaporation and canopy transpiration. The multi-temporal thermal-infrared observations allows the applications of a time-differencing in land surface temperature (LST), which minimizes the errors in LST retrieval, while the multiple angles and the very detailed spatial resolution permits the estimation of soil and canopy temperatures as well as the land surface properties needed in ET models to partition energy fluxes between soil and plant canopy components. This approach builds upon the state-of-the-art Two Source Energy Balance (TSEB) models, combined with Radiative Transfer Models (RTM) and inversion techniques in order to improve the characterization of biophysical properties of the land surface that play a critical role in affecting ET, such as leaf area index and albedo as well as canopy height, cover and architecture. Preliminary results show there are significant advantages in using very high resolution remote sensing data for heterogeneous agricultural landscapes allowing for better monitoring of ET and water management related to irrigation scheduling and crop production assessment. However, further research is needed to investigate the effects of such heterogeneous canopies on the radiation regime, turbulent transport of heat and water, and heat advection from adjacent bare soil areas.