1. UAH Ground-based Ozone Lidar - A New NDACC Lidar Station Member NDACC Lidar Working Group Meeting, NASA/JPL, Table Mountain, CA Nov. 4, 2013 http://nsstc.uah.edu/atmchem Shi Kuang 1, Mike Newchurch 1, John Burris 2, Wesley Cantrell 1 1 UAHuntsville, 2 NASA/GSFC UAH Robert Cramer Research Hall

2. Outline 1. Introduction to the location 2. Introduction to the UAH O3 lidar instrument 3. Other synergistic instruments at UAH 4. Future plans

3. The Location Simulated and obs (circles) organic carbon at surface in 2010. Surrounded by large cities. Leibensperger et al. ACP 2012 [Cooper et al., 2007] Summertime upper tropospheric O3 maximum above Huntsville Overview (34.7250N, 86.6450W) 200m ASL ~100 clear days and ~100 cloudy days per year

4. Current UAH Ozone Lidar Configuration UAH O3 DIAL The UAH O3 DIAL currently measures O3 with two λ (289-299), three telescopes, and four altitude channels. This system profiles O3 up to ~12 km with a temporal resolution 2-10 min and a vertical resolution of 150-750 m. We have plans to add a third λ for more accurate PBL O3 retrievals. 1 4 Licel TR PMT 30Hz, 5-7 mJ/pulse 10cm 40cm Telescope 2 3 2.5cm 10% 90% 289/299 Beamsplitter Pin hole or iris x z 289/299 laser Solar & ND filters Pulse generator Photodiode Function generator 289/299 Gate Trigger

5. Laser Transmitter Upgraded the transmitter from dye lasers to Raman-shifted lasers for a more stable output, quicker initialization, and easier operation. Data after May 2013 are mostly taken with the 289- 299nm pair. Previous: 532 YAG pumped dye lasers (285-291nm) Current: 266 YAG pumped Raman- shifted (289-299nm) 266 Pump

6. Receiver and Detector 1’’ receiver (Ch-1) 100m-1km Laser outgoing mirror 16’’ receiver (Ch-4) 3-12km 4’’ receiver (Ch-2 and Ch-3) 500m-1.5km, 1-5km 3 telescopes and 4 photomultiplier (PMT) channels Measurable alt range Added a 1’’ channel in Feb. 2013.

7. Validation Figure 11. Comparison of the low-altitude (solid) and high-altitude (dash) channel aerosol-corrected retrievals with the coincident ozonesonde (dot) measurements. O 3 (10 12 molec cm -3 ) Alt (km) [Kuang et al. 2013 Applied Optics][Kuang et al. 2011a IEEE-TGRS] The retrieval accuracy ranges from better than 10% in the low and mid troposphere and better than 20% in the upper troposphere with 2-10 min temporal integration. 1.Against sondes in [Kuang et al. 2011a] 2.Preliminary results in [Kuang et al. 2013] 3.Confirmed by the extensive coincident lidar/sonde obs. in 2013 summer SEAC4RS.

8. Synergistic Instruments at UAH Ozonesonde, T, P, O3, RH, wind Courtesy of Kevin Knupp http://vortex.nsstc.uah.edu/mips/system/ Sfc Sodar Ceilometer 915 profiler MPR 915: SNR, vertical velocity, spectral width, horizontal wind, Doppler spectra Ceilometer: backscatter, cloud base height MPR: T, water vapor, cloud water Sodar: SNR, spectral width, horizontal wind Surface; T, RH, P, wind, solar radiation Source: [Karan and Knupp, 2006] Halo Doppler wind lidar: wind velocity, backscatter, scanning capability

9. Synergistic Instruments at UAH Image from the manufacture Surface O3 monitor, high temporal O3 mixing ratio Wisconsin HSRL (Ed Eloranta et al.) deployed at Huntsville in 2013 summer: backscatter, color ratio, depolarization ratio.

10. Future Plans 1. Taking data on the NDACC schedule and achieving data using the NDACC protocol. 2. Improving the retrieval precision by adding a third wavelength (283.6nm). 3. Adding 289nm narrow-band and 283- 289nm band-pass filters. 4. Continuing scientific studies using the ozone lidar data.

11. Backup Slides

12. Table 1. Characteristics of the UAH ozone lidar. Specification Transmitter Pump lasersNd:YAG, 30-Hz repetition rate, 25-30 mJ·pulse -1 at 266 nm Raman cell2.5 cm of diameter and 185 cm of length Raman gasesN2 and He for 283.6 nm, D2 and He/Ar for 289 nm, H2 and Ar for 299 nm, Emitted UV light 7-10 mJ·pulse -1 at 285 and 291 nm; 4-5 mJ·pulse -1 at 283.6 nm, ~7-ns pulse length and divergence<1 mrad for all laser beams Receiver Channel 1Channel 2Channel 3Channel 4 Diameter (cm)2.510 40 Focal length (m)0.12.3 4.5 Separation from the laser beams (cm)1020 50 FOV (mrad)104.3 1.5 Full overlap height (m)2090 1200 Light split percentage (%)1001090100 Solar blind filter Center wavelength at 286.4 nm with a 11-nm FWHM; 35% Transmittance at 285 nm and 20% Transmittance at 291 nm Neutral density filter transmittance10% 32%NA PMT typeHamamatsu R9880UHamamatsu R7400U Electron Tube9831QA Gated PMT delay (μs)001>10 Measurable height range (km)0.1-10.4-1.51-43-12 Signal Processing Channel 1Channel 2Channel 3Channel 4 Photoncounting250-MHz maximum counting rate Analog12-bit and 40-MHz analog-to-digital converter Fundamental range resolution (m)3.75 Actual range resolution due to average (m)* 22.54575150 * This is equal to the range interval for reported ozone.

13. Planned Configuration of the UAH Ozone Lidar Planned configuration for UAH O3 DIAL The UAH O3 DIAL currently measures O3 with two λ (289-299), three telescopes, and four altitude channels. We have plan to add a third λ for more accurate PBL O3 retrievals. This system profiles O3 up to ~12 km with a temporal resolution 2-10 min and a vertical resolution of 150-750 m.