1. A Comparison of Doppler Lidar and Weather Balloon Wind Speed Profiles Patrick Selmer Research and Discover – UNH Advisors: Dr. Ivan Dors and Dr. James Ryan

2. Tackling the Data Void Space LIDAR vs Radiosonde Winds Source of both images and quote: Space-based Doppler Winds LIDAR: A Vital National Need. “The high value of tropospheric wind for improved weather prediction and climate studies is highlighted by the fact that it is ranked as the highest priority unmet measurement by NPOESS/IPO, a joint office representing DOD, NOAA and NASA.”

3. GroundWinds Program Develop & demonstrate remote sensing Doppler LIDAR technologies capable of measuring wind speeds from satellite Improve weather forecasting: Make the 5-day forecast as accurate as today’s 3-day forecast Bartlett, NHMauna Loa, HI Source: GroundWinds Web Page

4. Objectives Compare LIDAR and Weather Balloon wind profiles quantitatively Characterize inherent differences between the two measurement techniques Extract any other useful information from the comparison

5. LIDAR Time Averaged Fixed (ground) Remote Sensor Azimuth Sampled Doppler LIDAR vs. Weather Balloon Characteristic Differences Weather Balloon Instantaneous Drift (wind) In Situ Single Sampled

6. Comparative Measurements December 11, 2002 Adapted from Jumper Spatial Overlap Image to scale Balloon 1 Balloon 2 Balloon 3

7. Comparative Measurements Temporal Overlap Time UTC December 11 th local, 12 th UTC Adapted from Jumper 349 1 379394409379364349379 394 379364 2 34 5 67 89 10 1112 (Weather Balloons)

8. Wind Speed Comparison Can be thought of as the average error per altitude for a given pair of wind profiles Fit Error SSR = Σ(U lidar – U rad ) 2 n

9. Method of Comparison The 12-azimuth LIDAR data set was split-up to provide numerous wind profiles for comparison 1-3 12 Total Azimuth Scans 10 Sets of Three9 Sets of Four 2-43-54-6…10-121-42-53-64-7…9-12

10. Predictions Agreement between the wind profiles will improve with 1.Increased LIDAR azimuth angle span 2.Increased temporal overlap of measurements 3.Increased number of azimuths

11. Azimuth Span Anticipate better agreement with larger spans

12. Temporal Overlap Anticipate better agreement with coincident measurements Both 3 and 4-azimuth profile results Balloon 3 Launch

13. Conclusions Agreement increased with scanning range Agreement was not time-dependent –Steady atmosphere or not a dominant effect Agreement increased with the number of azimuth angles used –Using all twelve azimuths gave the best match

14. Special thanks to Dr. Ivan Dors for providing data and software and for all his help and support. I would also like to thank Dr. Jim Ryan, Dr. George Hurtt, and the entire Research and Discover team for making this presentation possible Acknowledgements

15. References Burroughs, John. "Data Coverage." Integrated Global Radiosonde Archive (IGRA). NESDES, 20 Aug. 2008. Web. 26 July 2009.. Institute for the Study of Earth, Oceans and Space University of New Hampshire. GroundWinds. University of New Hampshire. Web. 29 July 2009.. Jumper, George Y. Hawaii 2002 Thermosonde Campaign. Rep. Hayes, Paul, et al. Space-based Doppler Winds LIDAR: A Vital National Need. Rep. 2005. Print.