Academic Commons

Articles

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

Daleu, Chimene L.; Plant, Robert S.; Woolnough, Steve J.; Sessions, Sharon L.; Herman, Michael J.; Sobel, Adam H.; Wang, Shuguang; Kim, Daehyun; Cheng, A.; Bellon, Gilles; Peyrillé, Philippe; Ferry, Frédéric; Siebesma, Pier; van Ulft, Lambertus H.

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‐scale velocity profiles which are smoother and less top‐heavy compared to those produced by the WTG simulations. 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.

Files

  • thumnail for Daleu_et_al-2016-Journal_of_Advances_in_Modeling_Earth_Systems.pdf Daleu_et_al-2016-Journal_of_Advances_in_Modeling_Earth_Systems.pdf application/pdf 1.99 MB Download File

Also Published In

Title
Journal of Advances in Modeling Earth Systems
DOI
https://doi.org/10.1002/2015MS000570

More About This Work

Academic Units
Earth and Environmental Sciences
Applied Physics and Applied Mathematics
Published Here
January 23, 2019
Academic Commons provides global access to research and scholarship produced at Columbia University, Barnard College, Teachers College, Union Theological Seminary and Jewish Theological Seminary. Academic Commons is managed by the Columbia University Libraries.