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Satellite observations of atmospheric convection and gravity waves

Dr. L. Hoffmann, Forschungszentrum Jülich, JSC

On 4 May 2002 the National Aeronautics and Space Administration (NASA) launched the Aqua satellite aboard a Delta II rocket from Vandenberg Air Force Base, California, United States. The Aqua mission is part of NASA's Earth Observing System (EOS). Aqua is the first satellite in the `A-Train' constellation of satellites. Aqua operates at 705 km altitude in a Sun-synchronous polar orbit with 99 min period. Global coverage is achieved during 14.5 orbits per day. Six instruments on board Aqua monitor the global state of the Earth's atmosphere. The Atmospheric Infrared Sounder (AIRS) measures the thermal emissions of atmospheric constituents in the nadir and sub-limb observation geometry. AIRS applies a rotating mirror to carry out sub-limb scans in the across-track direction. A scan covers an across-track distance of 1700 km on the ground. AIRS provides Infrared spectra for nearly 3 million footprints per day. During its 10 year measurement period the satellite instrument provided about 50 TByte of data. This animation shows 8.1 micron brightness temperatures (color) from AIRS measurements on 1 January 2003. High brightness temperatures at 8.1 micron (red) indicate clear air conditions. Low values (blue) indicate the presence of clouds and convection.