Instrument Status and Science Plans for the Na Lidar at ALOMAR

1. Instrument Status and Science Plans for the Na Lidar at ALOMAR Biff Williams and Dave Fritts NorthWest Research Associates Colorado Research Associates Division in collaboration with Ulf-Peter Hoppe, Tim Dunker, JørgenØsterpart University of Oslo, Norway/FFI Sandra Blindheim and ALOMAR staff Andoya Rocket Range A collaboration of NWRA/CoRA, FFI/U. Tromso, ALOMAR Observatory, and Andoya Rocket Range. We thank IAP for the use of their 1.8m telescopes. The Na lidar has been supported by AFOSR contract F49620-03-C-0045, by NSF grants ATM-0137354, ATM-0137555, and ATM-0436703, and NASA contract NAG5-02036.

2. Introduction Raw data, 15sec integration, winter • The sodium lidar at ALOMAR in Norway (69N, 16E) has made measurements of the temperature, sodium density and radial wind profiles near the mesopause since August 2000. • Transmits 3 frequencies to measure Doppler shift and broadening of atmospheric Na resonance fluorescence. • Similar to other wind-temperature Na lidars operated by USU and UIUC, but with four times the telescope area. • The altitude range is approximately 78 to 105 km in winter and 85 to 97 km in summer. NWRA/CoRA ASAC 2011

3. Data Statistics • 1,588 hours of data in 10 years of operation • Observing hours was increasing with time, but back to average in 2010 with 137 hours of operation • 2009 best year with 289 hours of data as well as highest signal levels to date (500 counts/shot => 1,500 counts/sec/km) • 2008 second best year with 250 hours of data • Failures of resonator sum frequency crystal in seed laser in 2003 and 2007 ASAC 2011

4. Instrument Status • YAG pump laser: • Jan 2009: problems with YAG seeder. Affected temperature calibration but not winds. • Sep 2009: YAG seeder replaced => improved seeding • Will change from 50Hz to 30Hz to reduce heat load in laser and make synchronization easier with other lidars. • 589nm seed laser • PPLN waveguide module installed at ALOMAR in Mar 2010 and is operational. • Seed power increased a factor from 7mW to 30-70mW. • Output pulsed power increased by factor of 3-4 from 100-300mW to 300-1000mW => Back to specified pulse power levels • With 1.8m telescopes, two 500mW beams -> ~1K,1m/s photon noise error in 1min,1km integration in winter • Bernd Kaifler added a real-time pulsed spectrum and chirp measurement using 1GHz etalon and camera borrowed from IAP in 2009. Work in progress to add CW spectrum in between shots. Need to operate more consistently. ASAC 2011

5. New 4 beam system • 3x improved pulse output power => saturation of PMT’s in winter • Wind vector for DORIS => point large telescopes at 20E and 20N most of time • Fix new 91 cm telescope at 20 degrees off zenith to the west => fulltime option for momentum flux • Primary mirror mount installed, fiber holder at prime focus to be installed this week • Added pickoff mirror and fiber to 1m ozone lidar mirror to use with a zenith beam • Split 1W Na beam using beam splitters on flip mounts • Winter, 4 beams: 500mW for 20W, 250mW for 20E, 125mW for 20N, 125mW for zenith • Summer, 2 beams: 500mW for 20W, 500mW for 20N ASAC 2011

6. Renewal proposal for US lidar consortium • Proposal will be submitted today for 5 year renewal for US support of Na lidar through NSF Upper Atmosphere Facilities • Same funding source as ISR’s (Arecibo, Sondestrom, etc.) • Includes all US wind-temperature sodium lidars (NWRA, UIUC, USU, CU) • Focus on data and observations requested by outside users • Open data policy for US funded observations (not including FFI/U. Oslo/ARR funded observations) • Small guest investigator program: travel money for science collaborations in Boulder or for US users to go to ALOMAR • Adds funding to support PhD student to help with operations, analysis, and science -> looking for student now • Separate proposal already funded for a student to analyze Na lidar and Tmapper data from ALOMAR and Cerro Pachon, Chile. Also looking for a student for this ASAC 2011

7. Research Council of Norway support • Ulf Hoppe received a 2 year grant through U. Oslo • 60% funding level • Can continue to pay 1 ALOMAR unit per year. • Focus on collaboration with CARE II and DLR • Suggestions from ASAC for other priorities? • Jorgen Osterpart submitted Master’s thesis last week “Na lidar measurements during the ECOMA/Geminids campaign with focus on Na peak density and temperature” • Tim Dunker will submit Master’s thesis in May ASAC 2011

8. Current science topics • ECOMA Rocket Campaign– U. Hoppe, T. Dunker, J. Østerpart • Sporadic Na Layers – U. Hoppe, T. Dunker, J. Østerpart • Large vertical winds – B. Williams, D. Fritts • Zonal momentum flux – B. Williams, D. Fritts • DORIS + Na winds -> Wind Vector Profiles from 15-105 km – J. Hildebrand, G. Baumgarten • Comparison with Tromso Na lidar (T. Tsuda) • Gravity waves and ripples with Na Imager (S. Suzuki) and Tmapper (M. Taylor) ASAC 2011

9. ECOMA2010 • ECOMA 8 was launched at 03:24 UT 13 Dec 2010. • The sodium layer splits up into two branches • The upper part is most prominent at ~ 90 to 93 km • The lower part oscillates around 87 to 88 km. • The split lasts from 03:40 UT -04:23 UT (total 43 min). ASAC 2011

10. ECOMA2010 • The Richardson number plot exhibits instability (Ri < 0.25) in the same time and region as the main layer split-up. • Zonal and meridional wind profiles show wind-shears, e.g. 13 m/s per km in zonal wind speed. ASAC 2011

11. Waves near buoyancy period ASAC 2011

12. Waves near buoyancy period ASAC 2011

13. Large vertical winds • Hotpay2 rocket campaign • Data resolution: 1min, 3km • Wave properties: • 8min period, • long vertical wavelength • 30m/s vertical wind amplitude. • Na density and temperature consistent with vertical winds ASAC 2011

14. Large vertical winds • Hotpay2 rocket campaign • Data resolution: 1min, 3km • Wave properties: • 8min period, • long vertical wavelength • 30m/s vertical wind amplitude • Na density and temperature consistent with vertical winds ASAC 2011