Potential of soil —moisture-estimating technology for monitoring crop yields and assessing drought impacts-case studies in the United States

This study examines the potential of the soil moisture estimates generated by satellite based microwave sensors. Two case studies pertaining to the Nebraska and California states of the United States are presented. In Nebraska, using the 1995–2010 data, the soil moisture estimates were found to be significantly correlated (Coeff. of correlation = 0.56) with the yield of maize, the main crop of Nebraska. In California, using the 1997–2013 data, the soil moisture estimates were found to be strongly positively correlated with precipitation (Coeff. of corr. = 0.77), and the yields of walnuts (Coeff. of corr. = 0.61), oranges (Coeff. of corr. = 0.40), lemons (Coeff. of corr. = 0.32), almonds (Coeff. of corr. = 0.31) and pistachios (Coeff. of corr. = 0.15). The reliability of these relationships could be improved by confining the analysis to counties that have significant number of acres planted for respective crops. It is concluded that the soil moistures estimates is an important source of the data that can be used for improving crop models and for assessing agricultural drought impacts and thereby improving drought management.