Hi Facundo, > I am writing again because I did that I said in the previous mail and > retrieved ozone profiles are not bad, but the residual (yf-y) is not > around zero...It goes down to around 0.3 (the shape is good, but goes > down). It happens when I introduce the error related to T and H2O, and > also when I introduce only T or only H2O. Residual are very similar in > this 3 cases (T and H2O, T or H2O). When I do not include these errors > (only considering noise) it does not happen. I was looking for what is > wrong and I could not find it. Do you have any suggestion about it?
This is not easy to answer without having all the details at hand. Exactly how you calibrate the measurements, exact retrieval settings etc. Some questions: * What do you mean with good shape of the residual? * Do you make a non-linear retrieval? With T or H2O you might need to iterate to find the exact solution. * Do you include any POLYFIT? To include POLYFIT is quite standard, to reflect that your calibration newer is perfect. It is likely that the complete spectrum is wrong with roughly 1K just due to calibration issues. > On the other hand, what is exactly the use of the variable 'xnorm'? It is a feature to avoid numerical problems if your quantities have very different values. If you use Qpack, this is activated automatically, when could be needed. Bye, Patrick _______________________________________________ qpack mailing list [email protected] https://www.sat.ltu.se/mailman/listinfo/qpack
