Remote sensing - Topics

How do modern surveys remove a phantom island that older charts still show Which emerging geographic technologies are overhyped right now? Before and after imagery of a dam failure: what should you actually look for? Is it legal to publish satellite imagery of a sensitive military site? How do you calibrate a satellite index against measurements taken on the ground? Where can you download free global elevation data at 30 metre resolution? How do you date a satellite image when the web page gives no capture date? How can the shadow in an aerial photograph reveal the height of a building? How scientists map the seafloor with sonar and satellite gravity How do you read a false-colour satellite image and know what the red patches mean? Why is Google Earth imagery of some cities years newer than imagery of others? How close is real-time mapping to being genuinely useful in disaster response? How satellite altimetry measures the height of the ocean to the centimetre Why do free satellite archives have gaps over the oceans and the poles? Lidar vs photogrammetry for mapping terrain under dense forest: which wins? Are survey drones replacing manned aircraft for mapping work? Which national aerial imagery portals are worth using for free high-resolution photos? How do you spot a newly built structure in two images taken at different times? What is the practical difference between a satellite image and an aerial photograph? Can illegal logging really be caught from satellite pictures alone? Landsat or Sentinel for a thirty-year land cover study: which archive fits better? Passive vs active remote sensing: what is the practical difference? How the major land cover classifications disagree about what counts as forest How soil moisture measured by satellite improves flood forecasts What counts as geographic technology beyond GIS and GPS? What do the individual bands of a Sentinel-2 image actually measure? What does ground truth mean when you are validating a geographic dataset? How has the satellite era changed what counts as a geographical fact? NDVI explained: why does the vegetation index mislead during a drought? What GIS and remote sensing competitions ask students to build What are the limits of catching small-scale illegal mining by satellite? Land cover vs land use: why a satellite image cannot tell you who farms a field