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Validation of Water Vapor Vertical Distributions Retrieved from MAX-DOAS over Beijing, China. REMOTE SENSING 2020. [DOI: 10.3390/rs12193193] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Water vapor vertical profiles are important in numerical weather prediction, moisture transport, and vertical flux calculation. This study presents the Multi-Axis Differential Optical Absorption Spectroscopy (MAX-DOAS) retrieval algorithm for water vapor vertical profiles and the retrieved results are validated with corresponding independent datasets under clear sky. The retrieved Vertical Column Densities (VCDs) and surface concentrations are validated with the Aerosol Robotic Network (AERONET) and National Climatic Data Centre (NCDC) datasets, achieving good correlation coefficients (R) of 0.922 and 0.876, respectively. The retrieved vertical profiles agree well with weekly balloon-borne radiosonde measurements. Furthermore, the retrieved water vapor concentrations at different altitudes (100–2000 m) are validated with the corresponding European Centre for Medium-range Weather Forecasts (ECMWF) ERA-interim datasets, achieving a correlation coefficient (R) varying from 0.695 to 0.857. The total error budgets for the surface concentrations and VCDs are 31% and 38%, respectively. Finally, the retrieval performance of the MAX-DOAS algorithm under different aerosol loads is evaluated. High aerosol loads obstruct the retrieval of surface concentrations and VCDs, with surface concentrations more liable to severe interference from such aerosol loads. To summarize, the feasibility of detecting water vapor profiles using MAX-DOAS under clear sky is confirmed in this work.
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Nehrir AR, Kiemle C, Lebsock MD, Kirchengast G, Buehler SA, Löhnert U, Liu CL, Hargrave PC, Barrera-Verdejo M, Winker DM. Emerging Technologies and Synergies for Airborne and Space-Based Measurements of Water Vapor Profiles. SURVEYS IN GEOPHYSICS 2017; 38:1445-1482. [PMID: 31997843 PMCID: PMC6956949 DOI: 10.1007/s10712-017-9448-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Accepted: 10/06/2017] [Indexed: 06/10/2023]
Abstract
A deeper understanding of how clouds will respond to a warming climate is one of the outstanding challenges in climate science. Uncertainties in the response of clouds, and particularly shallow clouds, have been identified as the dominant source of the discrepancy in model estimates of equilibrium climate sensitivity. As the community gains a deeper understanding of the many processes involved, there is a growing appreciation of the critical role played by fluctuations in water vapor and the coupling of water vapor and atmospheric circulations. Reduction of uncertainties in cloud-climate feedbacks and convection initiation as well as improved understanding of processes governing these effects will result from profiling of water vapor in the lower troposphere with improved accuracy and vertical resolution compared to existing airborne and space-based measurements. This paper highlights new technologies and improved measurement approaches for measuring lower tropospheric water vapor and their expected added value to current observations. Those include differential absorption lidar and radar, microwave occultation between low-Earth orbiters, and hyperspectral microwave remote sensing. Each methodology is briefly explained, and measurement capabilities as well as the current technological readiness for aircraft and satellite implementation are specified. Potential synergies between the technologies are discussed, actual examples hereof are given, and future perspectives are explored. Based on technical maturity and the foreseen near-mid-term development path of the various discussed measurement approaches, we find that improved measurements of water vapor throughout the troposphere would greatly benefit from the combination of differential absorption lidar focusing on the lower troposphere with passive remote sensors constraining the upper-tropospheric humidity.
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Affiliation(s)
| | - Christoph Kiemle
- DLR, Institut für Physik der Atmosphäre, 82234 Oberpfaffenhofen, Germany
| | - Mathew D. Lebsock
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 USA
| | - Gottfried Kirchengast
- Wegener Center for Climate and Global Change (WEGC) and Institute for Geophysics, Astrophysics, and Meteorology/Inst. of Physics, University of Graz, Graz, 8010 Austria
| | - Stefan A. Buehler
- Center for Earth System Research and Sustainability (CEN), Meteorological Institute, Universität Hamburg, 20146 Hamburg, Germany
| | - Ulrich Löhnert
- Institute for Geophysics and Meteorology, University of Cologne, Pohligstr. 3, 50969 Cologne, Germany
| | - Cong-Liang Liu
- National Space Science Center (NSSC), Chinese Academy of Sciences, 100190 Beijing, China
| | - Peter C. Hargrave
- School of Physics & Astronomy, Cardiff University, 5 The Parade, Cardiff, CF24 3AA UK
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Pal S, Behrendt A, Bauer H, Radlach M, Riede A, Schiller M, Wagner, G, Wulfmeyer V. 3-dimensional observations of atmospheric variables during the field campaign COPS. ACTA ACUST UNITED AC 2008. [DOI: 10.1088/1755-1315/1/1/012031] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Ostermeyer M, Kappe P, Menzel R, Wulfmeyer V. Diode-pumped Nd:YAG master oscillator power amplifier with high pulse energy, excellent beam quality, and frequency-stabilized master oscillator as a basis for a next-generation lidar system. APPLIED OPTICS 2005; 44:582-590. [PMID: 15726956 DOI: 10.1364/ao.44.000582] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
A pulsed, diode-laser-pumped Nd:YAG master oscillator power amplifier (MOPA) in rod geometry, frequency stabilized with a modified Pound-Drever-Hall scheme is presented. The apparatus delivers 33-ns pulses with a maximum pulse energy of 0.5 J at 1064 nm. The system was set up in two different configurations for repetition rates of 100 or 250 Hz. The beam quality was measured to be 1.5 times the diffraction limit at a pulse energy of 405 mJ and a repetition rate of 100 Hz. At 250 Hz with the same pulse energy, the M2 was better than 2.1. The radiation is frequency converted with an efficiency of 50% to 532 nm. This MOPA system will be the pump laser of transmitters for a variety of high-end, scanning lidar systems.
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Affiliation(s)
- Martin Ostermeyer
- Institute of Physics, University of Potsdam, Potsdam 14469, Germany.
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Flentje H. Water vapor heterogeneity related to tropopause folds over the North Atlantic revealed by airborne water vapor differential absorption lidar. ACTA ACUST UNITED AC 2005. [DOI: 10.1029/2004jd004957] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Sprenger M. Tropopause folds and cross-tropopause exchange: A global investigation based upon ECMWF analyses for the time period March 2000 to February 2001. ACTA ACUST UNITED AC 2003. [DOI: 10.1029/2002jd002587] [Citation(s) in RCA: 137] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Offermann D, Schaeler B, Riese M, Langfermann M, Jarisch M, Eidmann G, Schiller C, Smit HGJ, Read WG. Water vapor at the tropopause during the CRISTA 2 mission. ACTA ACUST UNITED AC 2002. [DOI: 10.1029/2001jd000700] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- D. Offermann
- Department of Physics; University of Wuppertal; Wuppertal Germany
| | - B. Schaeler
- Department of Physics; University of Wuppertal; Wuppertal Germany
| | - M. Riese
- Institute of Chemistry and Dynamics of the Geosphere; Research Center Juelich GmbH; Juelich Germany
| | - M. Langfermann
- Daimler-Benz-Aerospace; Dornier GmbH; Friedrichshafen Germany
| | - M. Jarisch
- Department of Physics; University of Wuppertal; Wuppertal Germany
| | | | - C. Schiller
- Institute of Chemistry and Dynamics of the Geosphere; Research Center Juelich GmbH; Juelich Germany
| | - H. G. J. Smit
- Institute of Chemistry and Dynamics of the Geosphere; Research Center Juelich GmbH; Juelich Germany
| | - W. G. Read
- Jet Propulsion Laboratory; Pasadena California USA
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Wulfmeyer V, Walther C. Future performance of ground-based and airborne water-vapor differential absorption lidar. I. Overview and theory. APPLIED OPTICS 2001; 40:5304-5320. [PMID: 18364811 DOI: 10.1364/ao.40.005304] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
The performance of a future advanced water-vapor differential absorption lidar (DIAL) system is discussed. It is shown that the system has to be a direct-detection system operating in the rhovarsigmatau band of water vapor in the 940-nm wavelength region. The most important features of the DIAL technique are introduced: its clear-air measurement capability, its flexibility, and its simultaneous high resolution and accuracy. It is demonstrated that such a DIAL system can contribute to atmospheric sciences over a large range of scales and over a large variety of humidity conditions. An extended error analysis is performed, and errors (e.g., speckle noise) are included that previously were not been discussed in detail and that become important for certain system designs and measurement conditions. The applicability of the derived equation is investigated by comparisons with real data. Excellent agreement is found.
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Bruneau D, Quaglia P, Flamant C, Meissonnier M, Pelon J. Airborne Lidar LEANDRE II for Water-Vapor Profiling in the Troposphere. I. System description. APPLIED OPTICS 2001; 40:3450-3461. [PMID: 18360370 DOI: 10.1364/ao.40.003450] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
The airborne differential absorption lidar LEANDRE II, developed for profiling tropospheric water-vapor mixing ratios, is described. The emitter is a flash-lamp-pumped alexandrite laser, which operates in a double-pulse, dual-wavelength mode in the 727-736 nm spectral domain. Two 50-mJ successive on-line and off-line pulses with an output linewidth of 2.4 x 10(-2) cm(-1) and a spectral purity larger than 99.99% are emitted at a 50-mus time interval. The spectral positioning is controlled in real time by a wavemeter with an absolute accuracy of 5 x 10(-3) cm(-1). The receiver is a 30-cm aperture telescope with a 3.5-mrad field of view and a 1-nm filter bandwidth. These instrument characteristics are defined for measuring the water-vapor mixing ratio with an accuracy better than 0.5 g kg(-1) in the first 5 km of the atmosphere with a range resolution of 300 m, integration on 100 shots, and an instrumental systematic error of less than 2%. The sensitivity study and first results are presented in part II [Appl. Opt. 40, 3462-3475 (2001)].
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Saito Y, Weibring P, Edner H, Svanberg S. Possibility of Hard-Target Lidar Detection of a Biogenic Volatile Organic Compound, nu-Pinene Gas, Over Forest Areas. APPLIED OPTICS 2001; 40:3572-3574. [PMID: 18360386 DOI: 10.1364/ao.40.003572] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
The absorption spectrum of alpha-pinene gas, a biogenic volatile organic compound, was directly measured with a pulsed mid-infrared laser. The maximum absorption wavelength was found to be ~3.42 mum, and an absorption cross section of 4.8 x 10(-23) m(2) molec(-1) was obtained. A simple theoretical calculation with the measured spectral data showed that several hundreds of parts in 10(12) (ppt) of alpha-pinene gas in forest-mountain areas over a range of ~10 km were detectable by a long-path-averaged hard-target absorption lidar. Requirements for system development were also discussed.
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