Dear ARTS community, I have been interested in the issue of atmospheric radiative transfer simulation and inversion, where the simulation and inversion are basically built on ARTS, rather than calling ARTS via QPACK. however, I have recently run into a couple of problems, and I am asking for your advice. 1. Recently, I've been using ERA5 to reanalyze data and simulate bright temperature data from the Meteosat microwave thermometer. I constructed a 3D clear sky model, 3D cloud and rain models are currently more difficult, to simulate bright temperatures by matching atmospheric profiles to sensor latitude and longitude and orientation. The sensor model uses sensor_responseGenericAMSU, however, I found that the simulated bright temperature will have a large deviation from the actual, even up to 20 K. I think there is something wrong with this, have you ever had or seen related research, and what do you think the problem is? 2. The HITRAN database has a clear source of use, whereas Perrin, which is often used, is mixed, do you have a reference for this? 3. Regarding the Jacobi matrix for gases, I often express it in "rel" units, but how should it be represented in a graph? Something like K (kg/kg) I??d appreciate any tips on the best way to do this! Thanks in advance, Best wishes ZC
