8 posts
Map earthquake damage from free Sentinel-1 radar in Python. Compute the log ratio and a z-score against a pre-event stack for Antakya after the February 2023 Türkiye earthquakes, aggregate to a 200 m grid, and score the map against 730 destroyed buildings mapped in OpenStreetMap.
Estimate surface soil moisture from free Sentinel-1 radar in Python with the TU Wien change-detection method. Build dry and wet references per orbit, map relative soil moisture at 100 m, and test it honestly against four COSMOS-UK stations and their rain gauges.
Write the classic SAR speckle filters (boxcar, Lee, refined Lee, enhanced Lee, Frost and Gamma-MAP) in NumPy and SciPy, run them on Sentinel-1 over Rutland Water, and compare them by equivalent number of looks, edge preservation and speed.
Map volcano deformation with Sentinel-1 InSAR in Python: stream free COMET LiCSAR interferograms of the Svartsengi volcanic system in Iceland, read wrapped and unwrapped phase and coherence, count fringes, convert phase to line-of-sight millimetres, and combine ascending and descending tracks into vertical and east–west motion, checked against GNSS.
Map ground subsidence with Sentinel-1 InSAR in Python: stream 170 real interferograms of Mexico City, convert unwrapped phase to millimetres of line-of-sight motion, mask low coherence, invert a small-baseline network into a time series, and cross-check the velocity with MintPy.
Monitor crops through cloud with free Sentinel-1 radar. Build VV, VH and VH/VV ratio time series for 247 fields in Cambridgeshire, beat speckle by field-averaging, read the growth signatures of winter wheat and oilseed rape, and compare with the gaps that cloud leaves in Sentinel-2 NDVI.
Detect ships in free Sentinel-1 SAR imagery with a cell-averaging CFAR detector written in NumPy and SciPy: mask the land, set a threshold from a speckle model, cluster detections into targets, reject wind turbines, sidelobes and ambiguities, compare VV with VH and export the vessels as GeoJSON.
Map the 2022 Sindh floods with free Sentinel-1 radar from the Microsoft Planetary Computer: convert backscatter to decibels, remove speckle with a Lee filter, pick a water threshold with Otsu's method, and measure the flood extent and how it receded over seven months.