TY  - SER
AU  - Phetcharinthon Sriviha
AU  - Kazama,So
AU  - Loof,Rainer
AU  - Morishita,Hideharu
ED  - The Government of Australia,
TI  - Evaluation of evapotranspiration in Thailand using remote sensing data
T2  - Thesis
PY  - 1999///
CY  - Bangkok
PB  - Asian Institute of Technology
KW  - Evapotranspiration
KW  - Thailand
KW  - Remote sensing
N1  - A thesis submitted in partial fulfillment of the requirements for the degree of Master of  Engineering. School of Civil Engineering; Thesis (M.Eng.) - Asian Institute of Technology, 1999
N2  - Water balance method is used for the quantification of available water resources  potential for planning and decision making. In computing the water balance, whether for a  large or small area, the major factor in the equation is evapotranspiration, the problems,  encountered in the estimation of evapotranspiration are many, but are often simplified by point  estimates. The advent of Geographic Information System (GIS) and Remote Sensing have  made it possible to estimate the actual evapotranspiration on single parameter only. The  present study deals with the use of GIS and RS in five river basins, in the tropical region with  the monsoon.  The spatial variation of topography and vegetation coverage are estimated using GIS  and A VHRR (Advanced Very High Resolution Radiometer) sensor of NOAA (Nation  Oceanographic Atmospheric Administrator) satellite data respectively. NDVI (Normalized  Differential Vegetative Index) of each basin for both wet and dry season was calculated from  the reflectance of electromagnetic spectrum registered from the A VHRR satellite. The  monthly variation of rainfall, runoff and ground water storage change is investigated. The  wellknown rainfall-runoff Tank model is used to calibrate the hydrograph and to compute the  change in water storage. Putting these values in the water balance equation, monthly actual  evapotranspiration is computed. The least square method is carried out with the data set of  average NDVI in wet and dry season and actual evapotranspiration estimated from water  balance for all five basins to find out a relationship with a best fitted regression line. For  those, the logarithmic function is found more suitable for the estimation. This function is  applied to all basin to investigate the actual evapotranspiration distribution and produced  satisfactory result.
UR  - http://203.159.5.9/ait-thesis/detail.php?q=B12598
ER  -