An Examination of AIRS data during overshooting deep convection events observed from MODIS, CloudSat and CALIPSO data

Instruments onboard A-Train satellites provide a unique dataset for examining tropical deep convection that penetrates the stratosphere (referred to as overshooting events), toward clarifying stratospheric- tropospheric exchange of water vapor. The tropical deep convection events are detected using the MODIS/CloudSat joint data browser. Overshoots are determined by examining data from CloudSat and CALIPSO cloud top heights and comparing these values to the height of the tropical tropopause level. CloudSat and CALIPSO transects are then collocated with MODIS data. The MODIS brightness temperature differences between the 6.715 micrometer water vapor absorption line spectrum and the 11.08 micrometer atmospheric window are determined for all cases, revealing positive ?TB values for each event with a maximum ?TB of 5.16 K. The overshooting events are then examined using radiances within the water vapor absorption band measured by the high spectral resolution infrared sounder, AIRS to examine the detailed spectral signature that produces the positive brightness temperature differences. Results of this evaluation will be presented and the implications of this data on upper tropospheric/lower stratospheric humidity will be discussed.