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Pauly RM, Yorks JE, Hlavka DL, McGill MJ, Amiridis V, Palm SP, Rodier SD, Vaughan MA, Selmer PA, Kupchock AW, Baars H, Gialitaki A. Cloud Aerosol Transport System (CATS) 1064 nm Calibration and Validation. ATMOSPHERIC MEASUREMENT TECHNIQUES 2019; 12:6241-6258. [PMID: 33414857 PMCID: PMC7786814 DOI: 10.5194/amt-12-6241-2019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
The Cloud-Aerosol Transport System (CATS) lidar on board the International Space Station (ISS) operated from 10 February 2015 to 30 October 2017 providing range-resolved vertical backscatter profiles of Earth's atmosphere at 1064 and 532 nm. The CATS instrument design and ISS orbit lead to a higher 1064 nm signal-to-noise ratio than previous space-based lidars, allowing for direct atmospheric calibration of the 1064 nm signals. Nighttime CATS Version 3-00 data were calibrated by scaling the measured data to a model of the expected atmospheric backscatter between 22 and 26 km above mean sea level (AMSL). The CATS atmospheric model is constructed using molecular backscatter profiles derived from Modern-Era Retrospective analysis for Research and Applications, Version 2 (MERRA-2) re-analysis data and aerosol scattering ratios measured by the Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP). The nighttime normalization altitude region was chosen to simultaneously minimize aerosol loading and variability within the CATS data frame, which extends from 28 km to -2 km AMSL. Daytime CATS Version 3-00 data were calibrated through comparisons with nighttime measurements of the layer integrated attenuated total backscatter (iATB) from strongly scattering, rapidly attenuating opaque cirrus clouds. The CATS nighttime 1064 nm attenuated total backscatter (ATB) uncertainties for clouds and aerosols are primarily related to the uncertainties in the CATS nighttime calibration technique, which are estimated to be ~9%. Median CATS V3-00 1064 nm ATB relative uncertainty at night within cloud and aerosol layers is 7%, slightly lower than these calibration uncertainty estimates. CATS median daytime 1064 nm ATB relative uncertainty is 21% in cloud and aerosol layers, similar to the estimated 16-18% uncertainty in the CATS daytime cirrus cloud calibration transfer technique. Coincident daytime comparisons between CATS and the Cloud Physics Lidar (CPL) during the CATS-CALIPSO Airborne Validation Experiment (CCAVE) project show good agreement in mean ATB profiles for clear-air regions. Eight nighttime comparisons between CATS and the PollyXT ground based lidars also show good agreement in clear-air regions between 3-12 km, with CATS having a mean ATB of 19.7 % lower than PollyXT. Agreement between the two instruments (~7%) is even better within an aerosol layer. Six-month comparisons of nighttime ATB values between CATS and the Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) also show that iATB comparisons of opaque cirrus clouds agree to within 19%. Overall, CATS has demonstrated that direct calibration of the 1064 nm channel is possible from a space based lidar using the atmospheric normalization technique.
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Affiliation(s)
- Rebecca M Pauly
- Science Systems and Applications Inc., Lanham, 20706, United States
| | - John E Yorks
- NASA Godard Space Flight Center, Greenbelt, 20771, United States
| | - Dennis L Hlavka
- Science Systems and Applications Inc., Lanham, 20706, United States
| | - Matthew J McGill
- NASA Godard Space Flight Center, Greenbelt, 20771, United States
| | - Vassilis Amiridis
- National Observatory of Athens, Institute for Astronomy, Astrophysics, Space Application and Remote Sensing, Athens, Greece
| | - Stephen P Palm
- Science Systems and Applications Inc., Lanham, 20706, United States
| | - Sharon D Rodier
- Science Systems and Applications Inc., Hampton, 23666, United States
| | | | - Patrick A Selmer
- Science Systems and Applications Inc., Lanham, 20706, United States
| | | | - Holger Baars
- Leibniz Institute for Tropospheric Research (TROPOS), Leipzig, Germany
| | - Anna Gialitaki
- National Observatory of Athens, Institute for Astronomy, Astrophysics, Space Application and Remote Sensing, Athens, Greece
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Huang J, Hsu NC, Tsay SC, Holben BN, Welton EJ, Smirnov A, Jeong MJ, Hansell RA, Berkoff TA, Liu Z, Liu GR, Campbell JR, Liew SC, Barnes JE. Evaluations of cirrus contamination and screening in ground aerosol observations using collocated lidar systems. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/2012jd017757] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Su J, McCormick MP, Liu Z, Lee RB, Leavor KR, Lei L. Transmittance ratio constrained retrieval technique for lidar cirrus measurements. OPTICS LETTERS 2012; 37:1595-1597. [PMID: 22555749 DOI: 10.1364/ol.37.001595] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
This letter describes a lidar retrieval technique that uses the transmittance ratio as a constraint to determine an average lidar ratio as well as extinction and backscatter coefficients of transparent cirrus clouds. The cloud transmittance ratio is directly obtained from two adjacent elastic lidar backscatter signals. The technique can be applied to cirrus measurements where neither the molecular scattering dominant signals above and below the cloud layer are found nor cloudfree reference profiles are available. The technique has been tested with simulated lidar signals and applied to backscatter lidar measurements at Hampton University, Hampton, Virginia.
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Affiliation(s)
- Jia Su
- Center for Atmospheric Sciences, Department of Atmospheric and Planetary Sciences, Hampton University, Hampton, Virginia 23668, USA
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Vaughan MA, Liu Z, McGill MJ, Hu Y, Obland MD. On the spectral dependence of backscatter from cirrus clouds: Assessing CALIOP's 1064 nm calibration assumptions using cloud physics lidar measurements. ACTA ACUST UNITED AC 2010. [DOI: 10.1029/2009jd013086] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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McGill MJ, Vaughan MA, Trepte CR, Hart WD, Hlavka DL, Winker DM, Kuehn R. Airborne validation of spatial properties measured by the CALIPSO lidar. ACTA ACUST UNITED AC 2007. [DOI: 10.1029/2007jd008768] [Citation(s) in RCA: 132] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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