Dear Pauline, Just because the reviewer wrote LWP, I don't think you have to retrieve exactly LWP. Maybe the reviever meant "liquid water" when he/she wrote LWP!?
In fact, the most efficient way the estimate LWP is the retrieve the LWC profile. If my memory is correct, Rodgers makes a point of this in his book. Let me also make the point that a LWP of e.g. 0.3 mm will have different impact on the temperature retrieval if the water is found between e.g. 0-1 km, or 5-6 km. What matters is in fact the LWC profile. Bye, Patrick On 09/07/15 11:54, Pauline Martinet wrote: > Dear everybody, > > Sorry for all my questions these last days, I have two projects with > Qpack and I have to deal with both of them at the same time. > > I am reviewing an article using Qpack but the reviewer asks me to > simultaneously retrieve the liquid water path (LWP) with the temperature. > > I would like to modify the routine oem.m of Qpack to minimize the cost > function with respect to the liquid water path and not the liquid water > content profile. > > I have some ideas in mind: when I am in the oem.m routine like: > > 1) Modify the B matrix to only have one value for LWP instead of > background errors for the whole liquid water content profile > 2) After the computation of the Jacobians for the liquid water content > profile, change it to only have one value of Jacobians (delta TB with > respect to LWP) > 3) after finding the xstep that minimizes the cost function, go back > from the LWP increment to an increment on the whole liquid water content > profile. > Then, the new x profile is found, no modification for the convergence > test should be done. > > I do not know if it is more complicated then that as I do not know well > how the whole Qpack is coded, I mainly know this oem.m routine. > > Does anyone have ever done such a modification ? If not, does anyone > could help me doing it alone ? > and do you think it would take a lot of time. I only have 4 weeks to > send back my reviews. If it sounds too complicated, I will try > to explain to the reviewer this is not possible with the current version > of Qpack. > > Thank you very much in advance ! > > Best regards, > > Pauline > > ----- Météo-France ----- > Dr. Pauline Martinet > Chercheur CNRM/GMEI/LISA > [email protected] > Fixe : +33 561079031 > Site web: www.sites.google.com/site/martinetpauline31 > <https://www.sites.google.com/site/martinetpauline31/> > > > > _______________________________________________ > qpack mailing list > [email protected] > https://www.sat.ltu.se/mailman/listinfo/qpack > _______________________________________________ qpack mailing list [email protected] https://www.sat.ltu.se/mailman/listinfo/qpack
