Adjusting a model to estimate humidity content of soil by using TVDI in the State of Sinaloa, Mexico

Abstract

There are various direct and indirect methods used to estimate soil humidity. In remote perception or tele-detection, the TVDI, (Temperature-Vegetation Dryness Index), may be used, which uses terrestrial surface temperatures, and vegetation indexes as input standards. The proposal of this work is to present a quick manner of readjusting those figures where water bodies undergo some dry degree of the soil for the whole area of study. Four years were selected (2003, 2006, 2009 and 2012), the TVDI was estimated with input of MODIS products. An adjustment value was proposed based on the difference of the mean, and standard deviation of water bodies; this figure is applied to the resulting product, which lead to establish that water bodies show a humidity saturation of their soil. Adjustment values are different for each year of study. Humidity content is consistent to expected variability according to the various uses of soil and vegetation. Results agree with drought reports to the State of Sinaloa.