20240912 15430100 1.0 TRUE Stream Power Index (SPI) SPI measures the erosive power of surface runoff and thus, the index is a predictor variable of areas susceptible to debris-flow processes. The SPI map was generated using the following equation: SPI=ln(A*tan(S)), where A is the local upslope catchment area draining through a certain pixel in square meters and S is the local slope gradient in degrees. SPI ranges in the study area from -6.3 (yellow) to 19.1 (red).