Q: Is this new technology?
A: : In the 1970s there was some discussion about polarimetry, but aerosols were not a popular remote sensing topic at the time. Kuo-Nan Liou, one of the fathers of atmospheric radiative transfer, previously suggested flying polarimeters to sense ice clouds because we were having a difficult time with regular radiometers. The French space agency CNES flew a coarse-resolution polarimeter on the POLDER satellite, and NASA flew one on the Glory satellite that failed to reach orbit. So, we're just opening this door but it has a lot of potential.
The PODEX experiment is about developing an area of technology and remote sensing and getting it ready for space. If you look back two to six years before Terra, NASA flew simulators for the purpose of preparing for the MODIS instrument and to work on algorithm development for MODIS data. We're now trying to do that for the next generation of technology that we plan to fly in the early 2020s. We're not simply re-flying Terra or Aqua. This is a major step toward new technology to reduce errors and uncertainties in aerosol and cloud observations from space.
Q: Why fly three polarimeters?
A: PODEX is an experiment to provide a basis to push each of the existing polarimeter designs to greater maturity. The data we collect will greatly facilitate algorithm development data processing that allows us to derive geophysically relevant aerosol and cloud properties. This is where the real value of the measurements resides. For a satellite mission, we also need to be able to quickly process large volum
|Contact: Kathryn Hansen|
NASA/Goddard Space Flight Center