Climate research with the Atmospheric Infrared Sounder

The Atmospheric Infrared Sounder (AIRS) sounding suite, launched in 2002, is the most advanced atmospheric sounding system to date, with measurement accuracies far surpassing those of current operational weather satellites. From its sun-synchronous polar orbit, the AIRS system provides more than 300,000 all-weather soundings covering more than 90% of the globe every 24 hours. Usage of AIRS data products - available to all through the archive system operated by NASA - is spreading throughout the atmospheric and climate research community. An ongoing validation effort has confirmed that the system is very accurate and stable and is close to meeting the goal of providing global temperature soundings with an accuracy of 1 K per 1-km layer and water vapor soundings with an accuracy of 20% throughout the troposphere - surpassing the accuracy of radiosondes. This unprecedented data set is currently used for operational weather prediction in a number of countries, yielding significant positive impact on forecast accuracy and range. It is also enabling more detailed investigations of current issues in atmospheric and climate research. In addition to the basic soundings related to the hydrologic cycle, AIRS also measures a number of trace gases - the latest such product being the global distribution of carbon dioxide. We discuss some examples of recent research with AIRS data..