% IMPORTANT: The following is UTF-8 encoded.  This means that in the presence
% of non-ASCII characters, it will not work with BibTeX 0.99 or older.
% Instead, you should use an up-to-date BibTeX implementation like “bibtex8” or
% “biber”.

@ARTICLE{Woiwode:901998,
      author       = {Woiwode, Wolfgang and Dörnbrack, Andreas and Polichtchouk,
                      Inna and Johansson, Sören and Harvey, Ben and Höpfner,
                      Michael and Ungermann, Jörn and Friedl-Vallon, Felix},
      title        = {{T}echnical note: {L}owermost-stratosphere moist bias in
                      {ECMWF} {IFS} model diagnosed from airborne {GLORIA}
                      observations during winter–spring 2016},
      journal      = {Atmospheric chemistry and physics},
      volume       = {20},
      number       = {23},
      issn         = {1680-7324},
      address      = {Katlenburg-Lindau},
      publisher    = {EGU},
      reportid     = {FZJ-2021-03964},
      pages        = {15379 - 15387},
      year         = {2020},
      abstract     = {Numerical weather forecast systems like the ECMWF IFS
                      (European Centre for Medium-Range Weather Forecasts –
                      Integrated Forecasting System) are known to be affected by a
                      moist bias in the extratropical lowermost stratosphere (LMS)
                      which results in a systematic cold bias there. We use
                      high-spatial-resolution water vapor measurements by the
                      airborne infrared limb-imager GLORIA (Gimballed Limb
                      Observer for Radiance Imaging of the Atmosphere) during the
                      PGS (POLSTRACC/GW-LCYCLE-II/SALSA) campaign to study the LMS
                      moist bias in ECMWF analyses and 12 h forecasts from
                      January to March 2016. Thereby, we exploit the
                      two-dimensional observational capabilities of GLORIA, when
                      compared to in situ observations, and the higher vertical
                      and horizontal resolution, when compared to satellite
                      observations. Using GLORIA observations taken during five
                      flights in the polar sub-vortex region around Scandinavia
                      and Greenland, we diagnose a systematic moist bias in the
                      LMS exceeding $+50 \%$ (January) to $+30 \%$ (March) at
                      potential vorticity levels from 10 PVU (∼ highest
                      level accessed with suitable coverage) to 7 PVU. In the
                      diagnosed time period, the moist bias decreases at the
                      highest and driest air masses observed but clearly persists
                      at lower levels until mid-March. Sensitivity experiments
                      with more frequent temporal output, and lower or higher
                      horizontal and vertical resolution, show the short-term
                      forecasts to be practically insensitive to these parameters
                      on timescales of < 12 h. Our results confirm that the
                      diagnosed moist bias is already present in the initial
                      conditions (i.e., the analysis) and thus support the
                      hypothesis that the cold bias develops as a result of
                      forecast initialization. The moist bias in the analysis
                      might be explained by a model bias together with the lack of
                      water vapor observations suitable for assimilation above the
                      tropopause.},
      cin          = {IEK-7},
      ddc          = {550},
      cid          = {I:(DE-Juel1)IEK-7-20101013},
      pnm          = {2112 - Climate Feedbacks (POF4-211)},
      pid          = {G:(DE-HGF)POF4-2112},
      typ          = {PUB:(DE-HGF)16},
      UT           = {WOS:000599523900003},
      doi          = {10.5194/acp-20-15379-2020},
      url          = {https://juser.fz-juelich.de/record/901998},
}