Water vapour profiles from Raman lidar automatically calibrated by microwave radiometer data during HOPE

Abstract. In this paper, we present a method to derive water vapour profiles from Raman lidar measurements calibrated by the integrated water vapour (IWV) from a collocated microwave radiometer during the intense observation campaign HOPE in the frame of the HD(CP)2 initiative. The simultaneous observation of a microwave radiometer and a Raman lidar allowed an operational and continuous measurement of water vapour profiles also during cloudy conditions. The calibration method provides results which are in a good agreement with conventional methods based on radiosondes. The calibration factor derived from the proposed IWV method is very stable with a relative uncertainty of 5 %. This stability allows for the calibration of the lidar even in the presence of clouds using the calibration factor determined during the most recent clear sky interval. Based on the application of this approach, it is possible to retrieve water vapour profiles during all non-precipitating conditions. A statistical analysis shows a good agreement between the lidar measurements and collocated radiosondes. The relative biases amount to less than 6.7 % below 2 km.

[1]  David D. Turner,et al.  Automated Retrievals of Water Vapor and Aerosol Profiles from an Operational Raman Lidar , 2002 .

[2]  David N. Whiteman,et al.  Raman Lidar Measurements During the International H2O Project , 2006 .

[3]  Albert Ansmann,et al.  Continuous monitoring of the boundary-layer top with lidar , 2008 .

[4]  A. Bucholtz,et al.  Rayleigh-scattering calculations for the terrestrial atmosphere. , 1995, Applied optics.

[5]  A. Ansmann,et al.  Independent measurement of extinction and backscatter profiles in cirrus clouds by using a combined Raman elastic-backscatter lidar. , 1992, Applied optics.

[6]  David N. Whiteman,et al.  Atmospheric water vapor measurements: Comparison of microwave radiometry and lidar , 1992 .

[7]  Albert Ansmann,et al.  Relative-humidity profiling in the troposphere with a Raman lidar. , 2002, Applied optics.

[8]  Ina Mattis,et al.  RAMSES: German Meteorological Service autonomous Raman lidar for water vapor, temperature, aerosol, and cloud measurements. , 2012, Applied optics.

[9]  Chitra Sivaraman,et al.  Simultaneous analog and photon counting detection for Raman lidar. , 2009, Applied optics.

[10]  D. Easterling,et al.  Observations: Atmosphere and surface , 2013 .

[11]  R. Philipona,et al.  Raman Lidar for Meteorological Observations, RALMO – Part 2: Validation of water vapor measurements , 2012 .

[12]  Lucas Alados-Arboledas,et al.  Tropospheric water vapour and relative humidity profiles from lidar and microwave radiometry , 2013 .

[13]  P. Di Girolamo,et al.  The water vapour intercomparison effort in the framework of the Convective and Orographically‐induced Precipitation Study: airborne‐to‐ground‐based and airborne‐to‐airborne lidar systems , 2011 .

[14]  Christopher D. Barnet,et al.  Water Vapor Measurements by Howard University Raman Lidar during the WAVES 2006 Campaign , 2010 .

[15]  Steven E. Koch,et al.  An Overview of the International H2O Project (IHOP_2002) and Some Preliminary Highlights , 2004 .

[16]  Clemens Simmer,et al.  A network suitable microwave radiometer for operational monitoring of the cloudy atmosphere , 2005 .

[17]  A. Ansmann,et al.  Aerosol-type-dependent lidar ratios observed with Raman lidar , 2007 .

[18]  Albert Ansmann,et al.  Portable Raman Lidar Polly XT for Automated Profiling of Aerosol Backscatter, Extinction, and Depolarization , 2009 .

[19]  S. Clough,et al.  Dry Bias and Variability in Vaisala RS80-H Radiosondes: The ARM Experience , 2003 .

[20]  Beat Schmid,et al.  Evaluation of daytime measurements of aerosols and water vapor made by an operational Raman lidar over the Southern Great Plains , 2006 .

[21]  T. Nagai,et al.  Comparisons of Raman Lidar Measurements of Tropospheric Water Vapor Profiles with Radiosondes, Hygrometers on the Meteorological Observation Tower, and GPS at Tsukuba, Japan , 2007 .

[22]  Susanne Crewell,et al.  Accuracy of cloud liquid water path from ground‐based microwave radiometry 1. Dependency on cloud model statistics , 2003 .

[23]  D. Summa,et al.  Multiparameter Raman Lidar Measurements for the Characterization of a Dry Stratospheric Intrusion Event , 2009 .

[24]  S. H. Melfi,et al.  Raman lidar system for the measurement of water vapor and aerosols in the Earth's atmosphere. , 1992, Applied optics.

[25]  Lindsay J. Bennett,et al.  The Convective and Orographically‐induced Precipitation Study (COPS): the scientific strategy, the field phase, and research highlights , 2011 .

[26]  Vincenzo Cuomo,et al.  CIAO: the CNR-IMAA advanced observatory for atmospheric research , 2010 .

[27]  Susanne Crewell,et al.  Principles of Surface-based Microwave and Millimeter wave Radiometric Remote Sensing of the Troposphere , 2006 .

[28]  A. Tompkins.  A Prognostic Parameterization for the Subgrid-Scale Variability of Water Vapor and Clouds in Large-Scale Models and Its Use to Diagnose Cloud Cover , 2002 .

[29]  Susanne Crewell,et al.  Accuracy of Boundary Layer Temperature Profiles Retrieved With Multifrequency Multiangle Microwave Radiometry , 2007, IEEE Transactions on Geoscience and Remote Sensing.

[30]  D. Dionisi,et al.  Calibration of a Multichannel Water Vapor Raman Lidar through Noncollocated Operational Soundings: Optimization and Characterization of Accuracy and Variability , 2010 .

[31]  R. Engelmann,et al.  Comparison of Raman Lidar Observations of Water Vapor with COSMO-DE Forecasts during COPS 2007 , 2011 .

[32]  David N Whiteman,et al.  New Examination of the Traditional Raman Lidar Technique II: Evaluating the Ratios for Water Vapor and Aerosols , 2013 .

[33]  S. Twomey,et al.  Aerosols, clouds and radiation , 1991 .

[34]  B. Soden,et al.  WATER VAPOR FEEDBACK AND GLOBAL WARMING 1 , 2003 .

[35]  Mariana Adam,et al.  Systematic distortions in water vapor mixing ratio and aerosol scattering ratio from a Raman lidar , 2007, SPIE Remote Sensing.

[36]  L. Mona,et al.  Characterization of the variability of the humidity and cloud fields as observed from a cluster of ground‐based lidar systems , 2007 .

[37]  C. Weitkamp.  Lidar, Range-Resolved Optical Remote Sensing of the Atmosphere , 2005 .

[38]  Zhien Wang,et al.  Raman Lidar Measurements during the International H2O Project. Part II: Case Studies , 2006 .

[39]  D. Shindell,et al.  Anthropogenic and Natural Radiative Forcing , 2014 .

[40]  David N. Whiteman,et al.  A Comparison of Water Vapor Measurements Made by Raman Lidar and Radiosondes , 1995 .

[41]  David D. Turner,et al.  Twenty-Four-Hour Raman Lidar Water Vapor Measurements during the Atmospheric Radiation Measurement Program’s 1996 and 1997 Water Vapor Intensive Observation Periods , 1999 .