[arts-users] Polarized brightness temperature
Dear ARTS community, I am currently using the HITRAN spectral database. May I ask what version of the hitran. par file can be read using the ReadHITRAN method? How can I obtain different versions of the hitran database from different historical periods? Is it only the latest that can be obtained from the official website? Looking forward to your reply！Thank you! Best wishes, Jiaan He
Re: [arts-users] Polarized brightness temperature
Hi Patrick， Thank you for your quick reply, the advice you provided is very helpful, thank you again very much! Best wishes, Jiaan He At 2023-10-18 01:11:31, "Patrick Eriksson" wrote: >Hi, > >The only way to get ARTS to do QV and QH automatically, is to use a >"system" denoted as metmm. You find it in folder > >arts/controlfiles/instruments/metmm > >It is not totally straightforward to use and the documentation is not >extensive. As far as I know, the documentation is basically the file >TestMetMM.arts. > >The sensor definitions are found in sub-folder sensor_descriptions. >Inside these QV and QH are denoted AMSU-V and AMSU-H. This assumes that >QH and Qv work in the same way for all cross-track microwave radiometer. >I assume this is true, but I am not 100% sure. > >Bye, > >Patrick > > > >On 2023-10-17 14:15, suifengbenpao2023 wrote: >> Dear ARTS community, >> >> >> ARTS provides calculation methods for vertical polarization and >> horizontal polarization. However, many sensors are now set up with QH >> and QV polarization. I simulated the brightness temperature of a >> satellite borne microwave radiometer channel at 23.8GHz (QH >> polarization) over the ocean using a one-dimensional atmosphere, and the >> first Stokes vector I obtained was close to the observed QH polarization >> brightness temperature. However, the simulated brightness temperature of >> H polarization （instrument_pol, [6] ) was significantly different from >> the observed QH brightness temperature, May I ask if it is possible to >> simulate the QH polarization of spaceborne radiometers through the H >> polarization of ARTS? Is it still possible that I input other variables >> incorrectly? >> >> >> Looking forward to your reply！Thank you! >> >> Best wishes, >> >> Jiaan He
Re: [arts-users] Polarized brightness temperature
Hi, The only way to get ARTS to do QV and QH automatically, is to use a "system" denoted as metmm. You find it in folder arts/controlfiles/instruments/metmm It is not totally straightforward to use and the documentation is not extensive. As far as I know, the documentation is basically the file TestMetMM.arts. The sensor definitions are found in sub-folder sensor_descriptions. Inside these QV and QH are denoted AMSU-V and AMSU-H. This assumes that QH and Qv work in the same way for all cross-track microwave radiometer. I assume this is true, but I am not 100% sure. Bye, Patrick On 2023-10-17 14:15, suifengbenpao2023 wrote: Dear ARTS community, ARTS provides calculation methods for vertical polarization and horizontal polarization. However, many sensors are now set up with QH and QV polarization. I simulated the brightness temperature of a satellite borne microwave radiometer channel at 23.8GHz (QH polarization) over the ocean using a one-dimensional atmosphere, and the first Stokes vector I obtained was close to the observed QH polarization brightness temperature. However, the simulated brightness temperature of H polarization （instrument_pol, [6] ) was significantly different from the observed QH brightness temperature, May I ask if it is possible to simulate the QH polarization of spaceborne radiometers through the H polarization of ARTS? Is it still possible that I input other variables incorrectly? Looking forward to your reply！Thank you! Best wishes, Jiaan He
[arts-users] Polarized brightness temperature
Dear ARTS community, ARTS provides calculation methods for vertical polarization and horizontal polarization. However, many sensors are now set up with QH and QV polarization. I simulated the brightness temperature of a satellite borne microwave radiometer channel at 23.8GHz (QH polarization) over the ocean using a one-dimensional atmosphere, and the first Stokes vector I obtained was close to the observed QH polarization brightness temperature. However, the simulated brightness temperature of H polarization （instrument_pol, [6] ) was significantly different from the observed QH brightness temperature, May I ask if it is possible to simulate the QH polarization of spaceborne radiometers through the H polarization of ARTS? Is it still possible that I input other variables incorrectly? Looking forward to your reply！Thank you! Best wishes, Jiaan He
Re: [arts-users] Polarized brightness temperature
Hi Patrick,Thank you for your help! I tried the method you provided and it shows that TBv=TB(I)+TB(Q),TBh=TB(I)-TB(Q). So does that mean TB(Q)=(TBv-TBh)/2. Not sure if I have to understand correctly? Note: TB stands for brightness temperature. Looking forward to your reply again, thanks! Sincerely， Jiaan He. At 2023-10-10 18:50:31, "Patrick Eriksson" wrote: >Hi, > >For theory, see Sec 5.7 of doi:10.1016/j.jqsrt.2011.03.001 >Note especially Eq 19. > >To automatically extract V and/or H inside ARTS, you need to use >sensor_responsePolarisation, with polarisations measured/wanted >specified by instrument_pol. > >Bye, > >Patrick > >On 2023-10-09 09:32, suifengbenpao2023 wrote: >> Dear ARTS community, >> >> >> Currently I am simulating H and V polarization brightness temperatures, >> but I found that the polarization calculation in the description is not >> the same as the traditional radiation calculation (Q=Iv-Ih), so how >> should I calculate the brightness temperatures of H and V polarization >> from the stokes vector of brightness temperatures? How is it derived? >> >> >> Looking forward to your reply！Thank you! >> >> Best wishes, >> >> Jiaan He
Re: [arts-users] Polarized brightness temperature
Hi, For theory, see Sec 5.7 of doi:10.1016/j.jqsrt.2011.03.001 Note especially Eq 19. To automatically extract V and/or H inside ARTS, you need to use sensor_responsePolarisation, with polarisations measured/wanted specified by instrument_pol. Bye, Patrick On 2023-10-09 09:32, suifengbenpao2023 wrote: Dear ARTS community, Currently I am simulating H and V polarization brightness temperatures, but I found that the polarization calculation in the description is not the same as the traditional radiation calculation (Q=Iv-Ih), so how should I calculate the brightness temperatures of H and V polarization from the stokes vector of brightness temperatures? How is it derived? Looking forward to your reply！Thank you! Best wishes, Jiaan He
[arts-users] Polarized brightness temperature
Dear ARTS community, Currently I am simulating H and V polarization brightness temperatures, but I found that the polarization calculation in the description is not the same as the traditional radiation calculation (Q=Iv-Ih), so how should I calculate the brightness temperatures of H and V polarization from the stokes vector of brightness temperatures? How is it derived? Looking forward to your reply！Thank you! Best wishes, Jiaan He
