Synthetic Aperture Radar (SAR) is an interesting, albeit definitely non-trivial, remote sensing technology. As an actively sensing technology1 that is independent of both weather and of lighting conditions2. This property makes them a very interesting option for continuous monitoring tasks.
Depending on the wavelength used, SAR can penetrate vegetation, forests, ice, soil and even some structures and give us information about the conditions beneath. Polarization modes (upon emission and reception of signals) can highlight structural information. Through more advanced concepts such as interferometric SAR or InSAR3, we can measure very small deformations of the Earth’s surface from space, for example in volcanic or earthquake regions.
EarthByte Lab has compiled a small collection of sources for open SAR data. It features “usual suspects” such as Copernicus, NASA, USGS, but also covers newer and less known options, such as Umbra. The listed use cases are too generic to be very helpful, in my opinion, but the notes on availability and, of course, the access links are a good resource if you want to look into SAR.
If you aren’t yet familiar with SAR, you may also appreciate the brief explanatory video below.