HIRDLS high resolution measurements of the tropical tropopause layer

The High Resolution Dynamics Limb Sounder (HIRDLS) was designed to make measurements of temperature, cloud particles, O3, H2O, and 8 other species with higher vertical resolution than previously possible. During launch on the Aura satellite an unforeseen event occurred that created an obstruction over most of the optical entrance aperture, severely impacting the instrument's nominal performance. After a significant amount of work, an improved correction scheme has been developed that permits much of the original capability to be recovered. Results of data validation showing high precision and low systematic errors for temperature, ozone, and water vapor, as well as reliable detection of high cirrus, demonstrate the capabilities of the retrievals of the corrected radiances,.

Most of the presentation will be spent showing results of applying the data to investigate the vertical structure of temperature, water vapor, high cirrus and ozone in the tropical tropopause layer (TTL). The presentation will focus on the seasonal and longitudinal variations of this structure, and its response to tropical disturbances, especially the Asian Monsoon.