10:45 AM - 11:00 AM
[PEM12-25] The Whole Atmosphere Lidar: Obtaining wind and temperature profiles from ground to space by active remote sensing
★Invited Papers
Keywords:thermosphere, lidar, wind, temperature
In this presentation we will discuss the feasibility and prospects of a Whole Atmosphere Lidar which will allow vertically resolved measurements of wind and temperature from the ground to about 1000 km altitude. The unique capabilities of such an instrument, in particular the ability to measure profiles of neutral wind in the middle and upper thermosphere, will open a new window for studying space weather phenomena and vertical coupling in the atmosphere. However, given the substantial changes in density and atmospheric composition, lidars probing different atmospheric species have to be combined and technical challenges overcome. Fluorescence lidars probing the absorption lines of metallic atoms have been used to measure wind and temperature in the mesosphere/lower thermosphere (MLT) region for the last four decades. Extending the fluorescence lidar technique into the upper thermosphere requires targeting metastable helium because the number density of metallic species decreases rapidly with altitude above the MLT. At the German Aerospace Center (DLR) we built a pathfinder experiment, obtained profiles of metastable helium from about 350 to 1000 km altitude, and demonstrated the proof of concept for wind and temperature measurements in this altitude region. A calcium ion Doppler lidar that is currently in development at DLR will close the gap to the MLT. Below, measurements can be extended to the ground by conventional iron fluorescence and Rayleigh/Raman lidars. We will report on our development efforts, show results from our first thermospheric helium measurements, and provide a timeline for the implementation of the Whole Atmosphere Lidar.