Generate Topographic Position Index (TPI) in Earth Engine

In this video, I will show you how to generate a multi-scale topographic position index (mTPI) using Earth Engine. mTPI is a measure of the relative elevation of a location compared to its surroundings. It can help identify ridges and valleys, as well as other landforms and physiographic patterns. To calculate mTPI, we need elevation data and moving window size. I will use the 30m SRTM DEM as the elevation data source, and seven different window sizes ranging from 1.2 km to 115.8 km.

I will use Earth Engine’s image processing functions to subtract the mean elevation within each window from the original elevation value, resulting in an mTPI image for each window size. Then I will visualize and compare the mTPI images using different color palettes and map layers. By the end of this video, you will learn how to create your own mTPI maps using Earth Engine and explore their applications for climate adaptation planning and ecological analysis.

[Jay_Shikoyeni]

Im trying to fo that but it is failing

[macleidivarnier]

Hi Ramadhan. Great aplication, congratulations. Im trying to do a twi index in GEE. Do you know some way to do this?