A validation article by M. Diao and co-authors, published in the Journal of Geophysical Research, makes a comparison between AIRS/AMSU-A water vapour and temperature data with in situ aircraft measurements in the UTLS. They found that the absolute percentage difference between satellite and aircraft observations ranged between 20-60% and 1.0-2.5K, for water vapour and temperature observations, respectively. Land retrievals were found to be biased colder and drier than ocean retrievals at the UTLS, and no significant difference between hemispheres was found. Find the full abstract here.