Reply to comment by Jozsef Szilagyi on 'Assessing interannual variability of evapotranspiration at the catchment scale using satellite-based evapotranspiration data sets'

摘要

We would like to thank J. Szilagyi for his comment [Szilagyi, 2012] and for providing us an opportunity to restate the ideas of our paper [Cheng et al., 2011] about the interannual ET variability at the catchment scale. Using satellite-based evapotranspiration (ET) data sets, we found that a linear relationship can better characterize the interannual relationship between ET/P and PET/P (where P is annual precipitation, ET is evapotranspiration, and PET is annual potential ET estimated by Priestley and Taylor [1972]) than a nonlinear single-parameter Budyko-type curve for a particular catchment [Budyko, 1958]. Furthermore, we discussed the main controlling factors of the linear relationship, including filter effect of soil water, physiological responses of vegetation to climatic variability, and human interferences to the catchment water cycle.