% 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{Strelnikova:891694,
      author       = {Strelnikova, Irina and Almowafy, Marwa and Baumgarten, Gerd
                      and Baumgarten, Kathrin and Ern, Manfred and Gerding,
                      Michael and Lübken, Franz-Josef},
      title        = {{S}easonal {C}ycle of {G}ravity {W}ave {P}otential {E}nergy
                      {D}ensities from {L}idar and {S}atellite {O}bservations at
                      54° and 69°{N}},
      journal      = {Journal of the atmospheric sciences},
      volume       = {78},
      number       = {4},
      issn         = {1520-0469},
      address      = {Boston, Mass.},
      publisher    = {American Meteorological Soc.},
      reportid     = {FZJ-2021-01675},
      pages        = {1359 - 1386},
      year         = {2021},
      abstract     = {We present gravity wave climatologies based on 7 years
                      (2012–18) of lidar and Sounding of the Atmosphere using
                      Broadband Emission Radiometry (SABER) temperatures and
                      reanalysis data at 54° and 69°N in the altitude range
                      30–70 km. We use 9452 (5044) h of lidar observations at
                      Kühlungsborn [Arctic Lidar Observatory for Middle
                      Atmosphere Research (ALOMAR)]. Filtering according to
                      vertical wavelength (λz < 15 km) or period (τ < 8 h) is
                      applied. Gravity wave potential energy densities (GWPED) per
                      unit volume (EpV) and per unit mass (Epm) are derived. GWPED
                      from reanalysis are smaller compared to lidar. The
                      difference increases with altitude in winter and reaches
                      almost two orders of magnitude around 70 km. A seasonal
                      cycle of EpV with maximum values in winter is present at
                      both stations in nearly all lidar and SABER measurements and
                      in reanalysis data. For SABER and for lidar (with λ < 15
                      km) the winter/summer ratios are a factor of ~2–4, but are
                      significantly smaller for lidar with τ < 8 h. The
                      winter/summer ratios are nearly identical at both stations
                      and are significantly larger for Epm compared to EpV. Lidar
                      and SABER observations show that EpV is larger by a factor
                      of ~2 at Kühlungsborn compared to ALOMAR, independent of
                      season and altitude. Comparison with mean background winds
                      shows that simple scenarios regarding GW filtering, etc.,
                      cannot explain the Kühlungsborn–ALOMAR differences. The
                      value of EpV decreases with altitude in nearly all cases.
                      Corresponding EpV-scale heights from lidar are generally
                      larger in winter compared to summer. Above ~55 km, EpV in
                      summer is almost constant with altitude at both stations.
                      The winter–summer difference of EpV scale heights is much
                      smaller or absent in SABER and in reanalysis data.},
      cin          = {IEK-7},
      ddc          = {550},
      cid          = {I:(DE-Juel1)IEK-7-20101013},
      pnm          = {211 - Die Atmosphäre im globalen Wandel (POF4-211)},
      pid          = {G:(DE-HGF)POF4-211},
      typ          = {PUB:(DE-HGF)16},
      UT           = {WOS:000641862000021},
      doi          = {10.1175/JAS-D-20-0247.1},
      url          = {https://juser.fz-juelich.de/record/891694},
}