DOI: 10.5281/zenodo.2532028
title: The SPARC water vapour assessment II: Comparison of annual, semi-annual and quasi-biennial variations in stratospheric and lower mesospheric water vapour observed from satellites

description: Here we provide a NetCDF data set that contains the amplitudes and phases for the annual, semi-annual and quasi-biennial variations in stratospheric and lower mesospheric water vapour as observed by 30 satellite data sets. In addition, we combine the results from all data sets to provide average amplitudes and the corresponding standard deviations, among other.

The content description of the NetCDF file looks as follows:

netcdf results.amt-10-1111-2017 {<br>
dimensions:<br>
    dataset = 30 ;<br>
    string_length = 60 ;<br>
    latitude = 37 ;<br>
    bands = 2 ;<br>
    altitude = 59 ;<br>
variables:<br>
    char dataset_short(string_length, dataset) ;<br>
        dataset_short:standard_name = "data set" ;<br>
        dataset_short:long_name = "data set name" ;<br>
        dataset_short:description = "short label of data set" ;<br>
    char dataset_long(string_length, dataset) ;<br>
        dataset_long:standard_name = "data set" ;<br>
        dataset_long:long_name = "data set name" ;<br>
        dataset_long:description = "long label of data set" ;<br>
    double latitude(latitude) ;<br>
        latitude:standard_name = "latitude" ;<br>
        latitude:units = "degree_north" ;<br>
        latitude:minimum_value = "-90" ;<br>
        latitude:maximum_value = "90" ;<br>
        latitude:axis = "Y" ;<br>
        latitude:_CoordinateAxisType = "Lat" ;<br>
    double latitude_bands(bands, latitude) ;<br>
        latitude_bands:units = "degree_north" ;<br>
    double altitude(altitude) ;<br>
        altitude:standard_name = "altitude" ;<br>
        altitude:long_name = "pressure levels" ;<br>
        altitude:units = "hPa" ;<br>
        altitude:axis = "Z" ;<br>
        altitude:_CoordinateAxisType = "Alt" ;<br>
    double tropopause(latitude) ;<br>
        tropopause:standard_name = "tropopause" ;<br>
        tropopause:long_name = "tropopause pressure" ;<br>
        tropopause:description = "climatological tropopause pressure based on MERRA reanalysis data 2000 - 2014" ;<br>
        tropopause:units = "hPa" ;

// global attributes:<br>
        :summary = "this file contains the results published in Lossow et al. (2017)" ;<br>
        :url = "https://www.atmos-meas-tech.net/10/1111/2017/amt-10-1111-2017.html" ;<br>
        :project = "second SPARC water vapour assessment (WAVAS-II)" ;<br>
        :creator_name = "Stefan Lossow & Farahnaz Khosrawi" ;<br>
        :creator_email = "stefan.lossow@kit.edu & farahnaz.khosrawi@kit.edu" ;<br>
        :creator_email_supplemental = "stefan.lossow@yahoo.se & f.khosrawi@gmail.com" ;<br>
        :value_for_nodata = "NaN" ;<br>
        :date_created = "20190105T112425Z" ;

group: AO {<br>
  dimensions:<br>
      latitude = 37 ;<br>
      altitude = 59 ;<br>
      dataset = 30 ;<br>
  variables:<br>
      double amplitude(dataset, altitude, latitude) ;<br>
          amplitude:standard_name = "amplitude" ;<br>
          amplitude:long_name = "amplitude of the AO variation" ;<br>
          amplitude:description = "regression model is given by Eq. (1) in the manuscript; amplitude calculation based on Eq. (2)" ;<br>
          amplitude:units = "ppmv" ;<br>
      double phase(dataset, altitude, latitude) ;<br>
          phase:standard_name = "phase" ;<br>
          phase:long_name = "phase of the AO variation" ;<br>
          phase:description = "regression model is given by Eq. (1) in the manuscript; phase calculation based on Eq. (3)" ;<br>
          phase:units = "month" ;<br>
      double offset(dataset, altitude, latitude) ;<br>
          offset:standard_name = "offset" ;<br>
          offset:long_name = "offset component of the regression model" ;<br>
          offset:description = "regression model is given by Eq. (1) in the manuscript; meant for calculation of relative amplitudes" ;<br>
          offset:units = "ppmv" ;<br>
      double screening(dataset, altitude, latitude) ;<br>
          screening:standard_name = "screening" ;<br>
          screening:long_name = "screening for the amplitude and phase data" ;<br>
          screening:description = "screening matrix for the amplitude and phase data to calculate the standard deviations described in Sect. 3.3; 1 means screening; 0 means no screening" ;<br>
          screening:units = "" ;<br>
      double phase_difference(dataset, altitude, latitude) ;<br>
          phase_difference:standard_name = "phase difference" ;<br>
          phase_difference:long_name = "phase difference with respect to the reference data set" ;<br>
          phase_difference:reference_data_set_short = "MLS" ;<br>
          phase_difference:reference_data_set_long = "Aura/MLS v4.2" ;<br>
          phase_difference:description = "phase difference has been adapted so that it not exceeds the [-6,6] months interval by adding +/- 12 months; has been calculated after the screening" ;<br>
          phase_difference:units = "month" ;<br>
      double amplitude_standard_deviation(altitude, latitude) ;<br>
          amplitude_standard_deviation:standard_name = "standard deviation of amplitude" ;<br>
          amplitude_standard_deviation:long_name = "standard deviation of amplitude over all data sets" ;<br>
          amplitude_standard_deviation:description = "standard deviation calculation based on Eq. (6)" ;<br>
          amplitude_standard_deviation:units = "ppmv" ;<br>
      double amplitude_mean(altitude, latitude) ;<br>
          amplitude_mean:standard_name = "mean amplitude" ;<br>
          amplitude_mean:long_name = "mean amplitude over all data sets" ;<br>
          amplitude_mean:description = "mean calculation based on Eq. (6)" ;<br>
          amplitude_mean:units = "ppmv" ;<br>
      double amplitude_relative_standard_deviation(altitude, latitude) ;<br>
          amplitude_relative_standard_deviation:standard_name = "relative standard deviation of amplitude" ;<br>
          amplitude_relative_standard_deviation:long_name = "relatuve standard deviation of amplitude " ;<br>
          amplitude_relative_standard_deviation:description = "relavtive standard deviation calculation based on Eq. (6); uses \"amplitude_mean\" as reference" ;<br>
          amplitude_relative_standard_deviation:units = "ppmv" ;<br>
      double phase_difference_standard_deviation(altitude, latitude) ;<br>
          phase_difference_standard_deviation:standard_name = "standard deviation of phase difference" ;<br>
          phase_difference_standard_deviation:long_name = "standard deviation of phase difference over all data sets" ;<br>
          phase_difference_standard_deviation:description = "standard deviation calculation based on Eq. (7)" ;<br>
          phase_difference_standard_deviation:units = "month" ;<br>
      double phase_difference_mean(altitude, latitude) ;<br>
          phase_difference_mean:standard_name = "mean of phase difference" ;<br>
          phase_difference_mean:long_name = "mean of phase difference over all data sets" ;<br>
          phase_difference_mean:description = "mean calculation based on Eq. (7)" ;<br>
          phase_difference_mean:units = "month" ;<br>
  } // group AO

group: SAO {<br>
  dimensions:<br>
      latitude = 37 ;<br>
      altitude = 59 ;<br>
      dataset = 30 ;<br>
  variables:<br>
      double amplitude(dataset, altitude, latitude) ;<br>
          amplitude:standard_name = "amplitude" ;<br>
          amplitude:long_name = "amplitude of the SAO variation" ;<br>
          amplitude:description = "regression model is given by Eq. (4) in the manuscript; amplitude calculation based on Eq. (2)" ;<br>
          amplitude:units = "ppmv" ;<br>
      double phase(dataset, altitude, latitude) ;<br>
          phase:standard_name = "phase" ;<br>
          phase:long_name = "phase of the SAO variation" ;<br>
          phase:description = "regression model is given by Eq. (4) in the manuscript; phase calculation based on Eq. (3)" ;<br>
          phase:units = "month" ;<br>
      double offset(dataset, altitude, latitude) ;<br>
          offset:standard_name = "offset" ;<br>
          offset:long_name = "offset component of the regression model" ;<br>
          offset:description = "regression model is given by Eq. (4) in the manuscript; meant for calculation of relative amplitudes" ;<br>
          offset:units = "ppmv" ;<br>
      double screening(dataset, altitude, latitude) ;<br>
          screening:standard_name = "screening" ;<br>
          screening:long_name = "screening for the amplitude and phase data" ;<br>
          screening:description = "screening matrix for the amplitude and phase data to calculate the standard deviations described in Sect. 3.3; 1 means screening; 0 means no screening" ;<br>
          screening:units = "" ;<br>
      double phase_difference(dataset, altitude, latitude) ;<br>
          phase_difference:standard_name = "phase difference" ;<br>
          phase_difference:long_name = "phase difference with respect to the reference data set" ;<br>
          phase_difference:reference_data_set_short = "MLS" ;<br>
          phase_difference:reference_data_set_long = "Aura/MLS v4.2" ;<br>
          phase_difference:description = "phase difference has been adapted so that it not exceeds the [-3,3] months interval by adding +/- 6 months; has been calculated after the screening" ;<br>
          phase_difference:units = "month" ;<br>
      double amplitude_standard_deviation(altitude, latitude) ;<br>
          amplitude_standard_deviation:standard_name = "standard deviation of amplitude" ;<br>
          amplitude_standard_deviation:long_name = "standard deviation of amplitude over all data sets" ;<br>
          amplitude_standard_deviation:description = "standard deviation calculation based on Eq. (6)" ;<br>
          amplitude_standard_deviation:units = "ppmv" ;<br>
      double amplitude_mean(altitude, latitude) ;<br>
          amplitude_mean:standard_name = "mean amplitude" ;<br>
          amplitude_mean:long_name = "mean amplitude over all data sets" ;<br>
          amplitude_mean:description = "mean calculation based on Eq. (6)" ;<br>
          amplitude_mean:units = "ppmv" ;<br>
      double amplitude_relative_standard_deviation(altitude, latitude) ;<br>
          amplitude_relative_standard_deviation:standard_name = "relative standard deviation of amplitude" ;<br>
          amplitude_relative_standard_deviation:long_name = "relatuve standard deviation of amplitude " ;<br>
          amplitude_relative_standard_deviation:description = "relavtive standard deviation calculation based on Eq. (6); uses \"amplitude_mean\" as reference" ;<br>
          amplitude_relative_standard_deviation:units = "ppmv" ;<br>
      double phase_difference_standard_deviation(altitude, latitude) ;<br>
          phase_difference_standard_deviation:standard_name = "standard deviation of phase difference" ;<br>
          phase_difference_standard_deviation:long_name = "standard deviation of phase difference over all data sets" ;<br>
          phase_difference_standard_deviation:description = "standard deviation calculation based on Eq. (7)" ;<br>
          phase_difference_standard_deviation:units = "month" ;<br>
      double phase_difference_mean(altitude, latitude) ;<br>
          phase_difference_mean:standard_name = "mean of phase difference" ;<br>
          phase_difference_mean:long_name = "mean of phase difference over all data sets" ;<br>
          phase_difference_mean:description = "mean calculation based on Eq. (7)" ;<br>
          phase_difference_mean:units = "month" ;<br>
  } // group SAO

group: QBO {<br>
  dimensions:<br>
      latitude = 37 ;<br>
      altitude = 59 ;<br>
      dataset = 30 ;<br>
  variables:<br>
      double amplitude(dataset, altitude, latitude) ;<br>
          amplitude:standard_name = "amplitude" ;<br>
          amplitude:long_name = "amplitude of the QBO variation" ;<br>
          amplitude:description = "regression model is given by Eq. (5) in the manuscript; amplitude calculation based on Eq. (2)" ;<br>
          amplitude:units = "ppmv" ;<br>
      double phase(dataset, altitude, latitude) ;<br>
          phase:standard_name = "phase" ;<br>
          phase:long_name = "phase of the QBO variation" ;<br>
          phase:description = "regression model is given by Eq. (5) in the manuscript; phase is derived as the shift of the QBO regression fit for which the correlation with the Singapore (1N, 104E) winds at 50 hPa maximises" ;<br>
          phase:units = "month" ;<br>
      double offset(dataset, altitude, latitude) ;<br>
          offset:standard_name = "offset" ;<br>
          offset:long_name = "offset component of the regression model" ;<br>
          offset:description = "regression model is given by Eq. (5) in the manuscript; meant for calculation of relative amplitudes" ;<br>
          offset:units = "ppmv" ;<br>
      double screening(dataset, altitude, latitude) ;<br>
          screening:standard_name = "screening" ;<br>
          screening:long_name = "screening for the amplitude and phase data" ;<br>
          screening:description = "screening matrix for the amplitude and phase data to calculate the standard deviations described in Sect. 3.3; 1 means screening; 0 means no screening" ;<br>
          screening:units = "" ;<br>
      double phase_difference(dataset, altitude, latitude) ;<br>
          phase_difference:standar