What does AATSR tell us?
The information from AATSR is generated at several levels, ranging from counts of brightness temperature at the top of the atmosphere to global scale monthly averages of surface parameters, notably surface temperature, measured at thermal infrared wavelengths and surface reflectance, measured at selected visible and near infrared wavelengths. There is also a great deal of information about clouds, particularly their temperature and some of their optical characteristics. The main qualities of AATSR data which underpin its scientific importance are its excellent calibration, its dual view of the Earth's surface that can provide additional information about the atmosphere, its stability and its exceptionally precise image quality.
AATSR's capabilities mean that it has clear science drivers in several areas, primarily relating to the detection of climate change. The main scientific priorities to be addressed by AATSR can be grouped into five categories:
- Climate change
- Ocean processes
- Land surface processes
- The atmosphere, including clouds and aerosols
- The cryosphere
Climate change research will inevitably show considerable overlap with the other categories. Also, of these five categories, investigation of the atmosphere with AATSR observations is the science area that is developing most rapidly at present and the cryosphere is probably the least exploited area in the current AATSR exploitation programme.
For AATSR, climate change is undoubtedly the highest scientific priority, despite the fact that it encompasses all the others listed above.