Comparison of two satellite-based rainfall algorithms using Pacific atoll raingage data

Abstract

The linear regression relationship between monthly areal rainfall and the highly reflective cloud index agrees with earlier results. However, the GEOS precipitation index (GPI), which was calibrated using radar rainfall data obtained from the eastern tropical Atlantic, produces biased areal rainfall estimates over most of the tropical Pacific. However, its precision is greater than the highly reflective cloud index, perhaps due to the GPI's larger spatial dimensions. With the incorporation of calibration coefficients determined in this study, the GPI will produce unbiased estimates of areal rainfall for the tropical Pacific region. -from Authors