1. CALIPSO and LITE Data for Space-based DWL Design and Data Utility Studies: Research Plans: Part II Dave Emmitt, Simpson Weather Associates Dave Winker, Yongxiang Hu, Langley Research Center David Bowdle, University of Alabama in Huntsville Presented at: Meeting of the Working Group on Space-Based Lidar Winds Monterey, California, February 5-8, 2008

2. PREVIOUS AEROSOL BACKSCATTER STUDIES FOR SATELLITE WIND LIDARS NOAA: WindSat NASA/NOAA: GLOBE RSRE/USAF: SABLE/GABLE Community Model: Background/Enhanced SWA/LaRC: LITE/IceSat Backscatter/CLFOS Analyses

3. extend to other aerosol compositions and morphologies

4. extend to shorter wavelengths

5. Layer Detection Sensitivity: CALIPSO, 532 nm Day-night sensitivity differences are small, especially for low clouds Assuming layer thickness  = 300 m and lidar ratio= 20 horizontal averaging scales of CALIPSO standard data products: 1/3, 1, 5, 20, 80 km 532 nm backscatter (/km/sr)532 nm optical depth (/km)

6. Minimum Detectable Backscatter CALIPSO (532 nm vs. 1064, averaging to 20 km and 80 km) 1064 channel predicted to be slightly more sensitive than 532 at low altitude, but aerosol backscatter also tends to be lower at 1064.

7. Minimum Detectable Backscatter LITE vs. CALIPSO (532 nm, night, averaging to 20 km, 80 km) At night, LITE 532 nm is more sensitive than CALIPSO 532 nm. Due to larger LITE FOV and filter passband, daytime performance is similar. CALIPSO 1064 detector is better than LITE 1064 detector, so advantage of LITE is less than at 532 nm.

8. Minimum Detectable Backscatter CALIPSO (532 nm, night) Benefit of averaging to 500 km horizontal, 240 m vertical

9. QUESTIONS FOR THE LWG GLOBE/SABLE/GABLE was the only historical aerosol measurement program that was designed to characterize background aerosol backscatter in the middle and upper troposphere, in a manner suitable for inputs to simulations of satellite-based Doppler wind lidars that rely on aerosol wind tracers. These background studies were completed almost two decades ago.  How much has the backscatter background changed in two decades?  How much will the backscatter background change before future missions?  How would those changes affect OSSE’s for Doppler wind lidars?