High Resolution Measurements of the Tropical Tropopause Region by HIRDLS

The High Resolution Dynamics Limb Sounder (HIRDLS) was launched on the Aura satellite in July 2004. It was designed to make measurements of temperature, cloud particles, O3, H2O, and 8 other species with higher vertical resolution than previously possible. An unforeseen event occurred during launch that created an obstruction over most of the optical entrance aperture, creating a number of problems. After many months of work, a correction scheme has been developed that will permit much of the original capability to be recovered. To provide insight into the characteristics of this version of the data, the corrections for the effects of the oscillation of the blockage, the removal of the signal caused by the blockage, and the determination of the area remaining will be briefly noted. The results of initial data validation will be presented, including evidence for the vertical resolution of roughly 1 km for the data. These corrected data show the vertical structure of water vapor, high cirrus and ozone, and their relationship to the temperature, structure in the region of the tropical tropopause. The presentation will focus on the response of these quantities to tropical disturbances, especially the Asian Monsoon circulation.