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Title: Intercomparison of methods of coupling between convection and large-scale circulation: 2. Comparison over nonuniform surface conditions

As part of an international intercomparison project, the weak temperature gradient (WTG) and damped gravity wave (DGW) methods are used to parameterize large-scale dynamics in a set of cloud-resolving models (CRMs) and single column models (SCMs). The WTG or DGW method is implemented using a configuration that couples a model to a reference state defined with profiles obtained from the same model in radiative-convective equilibrium. We investigated the sensitivity of each model to changes in SST, given a fixed reference state. We performed a systematic comparison of the WTG and DGW methods in different models, and a systematic comparison of the behavior of those models using the WTG method and the DGW method. The sensitivity to the SST depends on both the large-scale parameterization method and the choice of the cloud model. In general, SCMs display a wider range of behaviors than CRMs. All CRMs using either the WTG or DGW method show an increase of precipitation with SST, while SCMs show sensitivities which are not always monotonic. CRMs using either the WTG or DGW method show a similar relationship between mean precipitation rate and column-relative humidity, while SCMs exhibit a much wider range of behaviors. DGW simulations produce large-scalemore » velocity profiles which are smoother and less top-heavy compared to those produced by the WTG simulations. Lastly, these large-scale parameterization methods provide a useful tool to identify the impact of parameterization differences on model behavior in the presence of two-way feedback between convection and the large-scale circulation.« less
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  1. Univ. of Reading, Reading (United Kingdom)
  2. New Mexico Tech, Socorro, NM (United States)
  3. Columbia Univ., New York, NY (United States)
  4. Univ. of Washington, Seattle, WA (United States)
  5. NASA Langley Research Center, Hampton, VA (United States)
  6. Univ. of Auckland, Auckland (New Zealand)
  7. Meteo France, Toulouse (France)
  8. Delft Univ. of Technology, Delft (Netherlands)
  9. Royal Netherlands Meteorological Institute, De Bilt (Netherlands)
Publication Date:
Grant/Contract Number:
SC0005450; SC0008779
Accepted Manuscript
Journal Name:
Journal of Advances in Modeling Earth Systems
Additional Journal Information:
Journal Volume: 8; Journal Issue: 1; Journal ID: ISSN 1942-2466
American Geophysical Union (AGU)
Research Org:
NASA Langley Research Center, Hampton, VA (United States)
Sponsoring Org:
USDOE Office of Science (SC)
Country of Publication:
United States
OSTI Identifier: