ground-based lidar network to provide ozone and aerosol data for air-quality study and geo-cap...
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Ground-based Lidar Network to Provide Ozone and Aerosol Data for Air-quality Study and
GEO-CAP mission
AQRS, Nov. 17, 2011
Mike Newchurch1, Shi Kuang1, R. J. Alvarez3, John Burris2, John Hair5, Mike Hardesty3, A. O. Langford3, Stuart McDermid6, Tom McGee2, Brad Pierce4, Christoph Senff3, Lihua Wang1
1UAHuntsville 2NASA/GSFC3NOAA/ESRL 4University of Wisconsin5NASA/LaRC 6NASA/JPL
Outline• I. Motivation• II. Scientific investigations• III. Hardware configurations
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I. Motivation of lidar measurements
• GEO-CAPE will measure tropospheric gases and aerosols at ~8km and hourly resolution. Vertical resolution is on the order of 5-10km in the troposphere. This vertical resolution is inadequate to resolve laminar structures that characterize tropospheric ozone and aerosols. Furthermore, GEO-CAPE information content in the PBL will likely be inadequate to resolve the processes responsible for air quality variability. We seek, therefore, to augment the spaceborne measurements with a ground-based measurement system.• Ozonesondes are extensively used in various atmospheric chemistry studies because of their low upfront cost and well-characterized behavior. However, the whole process for a sonde launch typically requires four hours. And four-hour ozonesonde resolution is prohibitively expensive. We therefore consider lidars to provide the necessary spatial and temporal resolution.
JPL-Table Mountain Facilityhttp://tmf-lidar.jpl.nasa.gov/index.htm
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Comparison of the techniques for ozone observation
a For OMI tropospheric ozone retrieval [Liu et al. 2010], [Worden et al. 2007]. b For ground-based only. The airborne lidar system can measure ozone with a 600-m spatial resolution, e.g., [ Langford et al. 2011]. c For ground-base system, e.g., Sunnesson et al.1994; Proffitt and Langford 1997; Kuang et al. 2011. The temporal resolution is strongly related to the retrieval uncertainty. Generally longer integration time will reduce the uncertainty arising from statistical error. d The estimated cost is based on $800/launch and launching 6 sondes every day.e Fishman J. et al. manuscript, in prep.
Ozonesonde Ground-based lidar Sun-synchronousSatellite (OMI) a
Geostationary satellite (GEO-CAPE)e
Vertical resolution ~100m 100-1000m 10-14km
Spatial coverage Point Point b Global Land and coastlines over 10-60oN band
Spatial resolution N/A N/A b 13X48km at nadir 8km
Temporal resolution Typically 1 week, max 4 hr 2-30 min c Typically 1 day 1 hr
Meas. uncertainty 10% Typically 10% at the near range and 20% at the far range
6%-35%
Cost Typically $40k/year, max $1,752k/year d
~$200-300k/year for fixed station
high high
Major strength well-characterized, low up-front cost, good vertical resolution,
High temporal resolution, low cost for frequent routine measurement
global coverage , high accuracy on total column retrieval
High spatio-temporal resolution relative to sun-sny satellite
Major weakness Low temporal resolution Unable to measure ozone above thick cloud, higher up-front cost relative to sonde
Low vertical resolution (particularly limited to resolve PBL)
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O3 measurement with a 4-hour temporal resolution
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ozonesonde
Lidar ozone curtain with10-minute resolution
II. Scientific investigations addressed by the lidar network
May 01 May 02 May 03 May 04 May 05 May 06 May 07 May 08
May 3, 2010
Daytime PBL top collapsed
Model (RAQMS) validation (simulated by B. Pierce)
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May 4 May 5
May 6 (high PBL O3)
Missed
May 7
EPA surface
Co-located ceilometer backscatter
Low-level jet
Co-located wind profiler
Positive correlation of ozone and aerosol due to transport
Oct. 4, 2008
Kuang et al. Atmospheric Environment 2011
Aerosol
Lidar
O3 Transport: Nocturnal O3 enhancement associated with low-level jet
Oct. 2, 08
Oct. 3, 08
Oct. 1, 08
Oct. 5, 08 Oct. 6, 08
Oct. 4, 08
Surface O3 and convective boundary layer height
Higher increasing rate of the surface O3 due to the low-level transport on the previous day
10Local time
GOME total O3 Nov. 5
Stratospheric O3, zero RH
Sonde
Stratosphere-to-troposphere transport and its CMAQ Model simulation, Nov. 5, 2010
Huntsville
Lidar O3
Ozonesonde showing the high O3 and dry layer
Modeled by Arastoo Pour-Biazar
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High-resolution PBL lidar observation suggests both UV and Vis radiances required to capture significant PBL signal for satellite
Huntsville lidar observation on Aug. 4, 2010
Lidar obs. convolved with OMI UV averaging kernel---- unable to capture the highly variable ozone structure in PBL
Lidar obs. Convolved with OMI UV-Vis averaging kernel----Captures the PBL ozone structure. X. Liu et al.
TOPAZ applications
TexAQS 2006: Quantifying horizontal transport of O3 downwind from Houston and Dallas
Cross sections of ozone downwind of Houston measured with TOPAZ on 08/14/2006. Ozone fluxes are computed for each transect by integrating above-background ozone across the plume and multiplying with horizontal wind speed measured with radar wind profilers.
Ozone fluxes as a function of plume age downwind from Houston and Dallas (includes data from TexAQS 2000).
Senff, C. J. et al., 2010: Airborne lidar measurements of ozone flux downwind of Houston and Dallas, J. Geophys. Res., 115, D20307, doi:10.1029/2009JD013689.
TOPAZ applications
Pre-CalNex 2009: Orographic lifting & long-range transport of O3 originating in the Los Angeles Basin
SMOG model predictions (top) comparedwith TOPAZ lidar observations (bottom).
48-h (solid) and 60-h (dotted) forward trajectories suggesting long-range transport aloft of O3 from Los Angeles to Utah and Colorado.
Langford, A. O., et al., 2010: Long-range transport of ozone from the Los Angeles Basin: A case study, Geophys. Res. Lett., doi:10.1029/2010GL042507.
Stratospheric contribution to high surface ozone in Colorado during springtime A.O. Langford, K.C. Aikin1, C.S. Eubank1, E.J Williams1
Chemical Sciences Division ESRL, NOAA, Boulder, Colorado USA 1also at Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, Colorado, USA.
Langford NOAA/ESRL/CSD
Stratospheric
Tropospheric
E.J. Williams
Surface O3 and CO anticorrelatedLangford NOAA/ESRL/CSD
CDPHE and NPS monitors
Surface O3 increased from 55 to 100 ppbv in RMNP!
Langford NOAA/ESRL/CSD
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JPL/TMF ozone & water vapor lidars
Ozone (left) and water vapor (Right) with 10 minute resolution showing the progression of a stratospheric intrusion and the anti-correlation between ozone and water.
O3 H2O
S. McDermid slides
III. Sites and the hardware configurations
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UAHNASA/LaRC
JPL/TMF
NOAA/ESRL
Initiative sites of the ground-based lidar network to provide O3 and aerosol data for air-quality study
and GEO-CAP mission
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NASA/GSFC
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UAHuntsville future configuration
1. 3- λ ( 284-289-299) system to minimize aerosol interference
2. Adding a 1-inch mini receiver channel to reduce the lowest measurement altitude to ~100m from the current 500m
Alt (km)
5
10
15
20
0H2
283.6
D2
289
N2
299
3mJ 9mJ 6mJ
30mJ30mJ
Small Receiver
Large Receiver
YAG266
30mJ
Dual DIAL and Higher resolution
Raman cell
YAG266
YAG266
Mini Receiver
Schematic diagram of the future transmitters, wavelength pairs, and their measurement ranges. Different colors refer to the different PMT channels.
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Diagram of the future receiving system- 3 receiver channels covering 0.1-12km
TOPAZ: NOAA’s airborne Ozone/Aerosol Lidar(TOPAZ = Tunable Optical Profiler for Aerosols and oZone)
• Compact, light-weight, all solid state lidar
• 3 tunable UV wavelengths
• Designed for nadir-looking deployment on NOAA Twin Otter
• Measures ozone and aerosol backscatter profiles
• Altitude coverage: from near the surface up to 5 km MSL
• Resolution (O3): 90 m vertical, 600 m horizontal
• Precision (O3) : 2-15 ppb
TOPAZ modifications for ground-based, scanning operation
1. Invert telescope to zenith-looking
2. Install in truck with roof top scanner
Scan strategy & expected performance of ground-based TOPAZ
Anticipated instrument performance
Time resolution: 1 min per angle; 5 min per scan sequence Range/altitude resolution: 90 m; 3 – 90 m Range/altitude coverage: 400 m – 4 km; 17 m – 4 km AGL Precision: 1 – 10 ppb (SNR and range dependent)
90º
10º
2º
17 m AGL
~4 km AGL
3-angle scan sequence designed to provide composite O3 profiles from 17 m to approx. 4 km AGL. Horizontal stares will be performed occasionally.
Deployments of ground-based TOPAZ in FY 2012
1. Uintah Basin Ozone Study (UBOS)
The UBOS study is designed to examine in detail the role of local atmospheric chemistry and meteorology in producing high wintertime O3 concentrations in the Uintah Basin in NE Utah.
TOPAZ will provide horizontal and vertical profiles of ozone as well as estimates of boundary layer height.
Time frame: February/March 2012
2. Local measurements (Boulder, Fritz Peak)
TOPAZ will measure vertical profiles of ozone at regular intervals at NOAA/ESRL in Boulder or at the Fritz Peak Observatory to a) provide a vertical context for the routine surface O3 observations in the greater Denver area and b) extend the record of mid-tropospheric ozone profile measurements by Langford et al. from the 1990s.
Time frame: April – September 2012
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LaRC ozone lidar
Telescope
Lidar ControlDAQ System
Receiver Box
Laser Transmitter
1. Ground-based, but can be modified to a mobile system2. Tunable two wavelengths within 282-313 nm for O3 measurement3. 527nm for aerosol measurement
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GSFC tropospheric ozone lidar
Schematic of the Non-Linear Optics bench within the laser. The Nd-YAG laser is mounted upside down on the underside of the NLO bench. The 1064 nm pump beam enters the NLO bench at the lower right.
Comparison of the target configurations of the O3 lidars at different sites
Site Characteristics Strength Weakness
JPL/TMF Quadruple YAG pumped raman laser, 3-λ,3-receiver
355nm channel measuring aerosol
Fixed location, Limited daytime measurements
NOAA/ESRL Nd:YLF pumped Ce:LiCAF tunable 2-λ,1-receiver, scanning, mobile
Tunable wavelength, Scanning, mobile
Only 2-λ, potential aerosol interference, limited alt measurement range
UAHuntsville Quadruple YAG pumped raman laser, 3-λ,3-receiver
Low PBL measurement, dual-DIAL removing aerosol effect
Fixed location, limited alt measurement range during daytime
NASA/GSFC High freq. OPO, 2-λ,1-receiver Tunable wavelength, can be mobile
Potential aerosol interference
NASA/LaRC Nd:YLF pumped Ce:LiCAF tunable 2-λ,1-receiver, scanning, mobile
Tunable wavelength, Scanning, mobile
Only 2-λ, potential aerosol interference, limited alt measurement range
Conclusion