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Title: Select strengths and biases of models in representing the Arctic winter boundary layer over sea ice: the Larcform 1 single column model intercomparison

We struggle to represent lower tropospheric temperature and moisture profiles and surface fluxes in Artic winter using weather and climate models, partly because they lack or misrepresent physical processes that are specific to high latitudes. Observations have revealed two preferred states of the Arctic winter boundary layer. In the cloudy state, cloud liquid water limits surface radiative cooling, and temperature inversions are weak and elevated. In the radiatively clear state, strong surface radiative cooling leads to the build-up of surface-based temperature inversions. Many large-scale models lack the cloudy state, and some substantially underestimate inversion strength in the clear state. The transformation from a moist to a cold dry air mass is modeled using an idealized Lagrangian perspective. The trajectory includes both boundary layer states, and the single-column experiment is the first Lagrangian Arctic air formation experiment (Larcform 1) organized within GEWEX GASS (Global atmospheric system studies). The intercomparison reproduces the typical biases of large-scale models: some models lack the cloudy state of the boundary layer due to the representation of mixed-phase microphysics or to the interaction between micro- and macrophysics. In some models, high emissivities of ice clouds or the lack of an insulating snow layer prevent the build-up ofmore » surface-based inversions in the radiatively clear state. Models substantially disagree on the amount of cloud liquid water in the cloudy state and on turbulent heat fluxes under clear skies. Finally, observations of air mass transformations including both boundary layer states would allow for a tighter constraint of model behavior.« less
 [1] ;  [2] ;  [3] ;  [4] ;  [5] ;  [2] ;  [6] ;  [7] ;  [8] ;  [8] ;  [4] ;  [9] ;  [10]
  1. Univ. of Reading (United Kingdom). Dept. of Meteorology
  2. NASA Goddard Inst. for Space Studies (GISS), New York, NY (United States)
  3. Univ. of Colorado and NOAA Earth System Research Lab., Boulder, CO (United States). Cooperative Institute for Research in Environmental Sciences (CIRES)
  4. Stockholm Univ. (Sweden). Dept. of Meteorology
  5. ETH Zurich (Switzerland). Inst. for Atmosphere and Climate
  6. National Center for Atmospheric Research, Boulder, CO (United States)
  7. European Centre for Medium-Range Weather Forecasts (ECNWF), Reading (United Kingdom)
  8. Wageningen Univ. (Netherlands). Meteorology and Air Quality Section
  9. NWP Research Center (RPN), Dorval, QC (Canada)
  10. Recherche en Prévision Numérique Atmosphérique, Environment Canada, Dorval Quebec Canada
Publication Date:
Grant/Contract Number:
FC02-97ER62402; GAP-654492; 863.10.010; 829.09.005
Accepted Manuscript
Journal Name:
Journal of Advances in Modeling Earth Systems
Additional Journal Information:
Journal Volume: 8; Journal Issue: 3; Journal ID: ISSN 1942-2466
American Geophysical Union (AGU)
Research Org:
University Corporation for Atmospheric Research (UCAR), Boulder, CO (United States); University of Corporation for Atmospheric Research, Boulder, CO (United States)
Sponsoring Org:
USDOE Office of Science (SC); National Science Foundation (NSF); Netherlands Organization for Scientific Research (NWO); National Aeronautic and Space Administration (NASA); European Research Council (ERC)
Country of Publication:
United States
OSTI Identifier:
Alternate Identifier(s):
OSTI ID: 1377370