When new sensor coefficient files are generated for recently launched satellites, are the coefficient files compatible with previous versions of CRTM? For example, will coefficient files for new sensors work in the older CRTM v2.1.3?
Depends on the sensor. Some do, and some don’t. Newer versions of legacy sensors (ATMS, AMSU, ABI, etc.) may work. However, we generally recommend updating your version of CRTM, because there have been many science and accuracy updates since v2.1.3.