Effects of time-dependent large-scale forcing, solar zenith angle, and sea surface temperature on time-mean rainfall: a partitioning analysis based on surface rainfall budget
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Effects of time-dependent large-scale forcing, solar zenith angle, and sea surface temperature on time-mean rainfall during the Tropical Ocean Global Atmosphere Coupled Ocean–Atmosphere Response Experiment (TOGA COARE) are examined through a partitioning analysis of a series of sensitivity cloud-resolving model experiment data based on surface rainfall budget. The model is forced by time-dependent large-scale forcing (LSF), solar zenith angle (SZA), and sea surface temperature (SST) in the control experiment and is forced only by either time-dependent LSF, SZA, or SST while others are replaced with their time averages in the sensitivity experiments. The rainfall associated with water vapor divergence and local atmospheric drying and hydrometeor loss/convergence has the largest contribution to total rainfall among eight rainfall types. The largest rainfall contribution is increased in the simulations where either time-dependent LSF, SZA, or SST is replaced with its average, whereas it is decreased in the simulation where COARE-derived large-scale vertical velocity is replaced with zero vertical velocity. The contribution of the rainfall associated with water vapor convergence to total rainfall is decreased in the simulations with time-mean LSF, SZA, and SST, whereas it is increased in the simulation without large-scale vertical velocity.
The authors thank Prof. M. Zhang, the State University of New York at Stony brook, for his TOGA COARE forcing data and the two anonymous reviewers for their constructive comments. This work was supported by the National Key Basic Research and Development Project of China No. 2009CB421505, the National Natural Sciences Foundation of China under the Grant No. 40930950 and 41075043.
- Chou M-D, Suarez MJ (1994): An efficient thermal infrared radiation parameterization for use in general circulation model. NASA Tech Memo 104606, vol 3, NASA/Goddard Space Flight Center, Code 913, Greenbelt, MD 20771Google Scholar
- Chou M-D, Suarez MJ, Ho C-H, Yan MM-H, Lee K-T (1998) Parameterizations for cloud overlapping and shortwave single scattering properties for use in general circulation and cloud ensemble models. J Atmos Sci 55:201–214Google Scholar
- Cui X, Li X (2006) Role of surface evaporation in surface rainfall processes. J Geophys Res, 111. doi: 10.1029/2005JD006876
- Gao S, Li X (2008) Cloud-resolving modeling of convective processes. Springer, Berlin, pp 206Google Scholar
- Sui C-H, Lau K-M, Tao W-K, Simpson J (1994) The tropical water and energy cycles in a cumulus ensemble model. Part I: equilibrium climate. J Atmos Sci 51:711–728Google Scholar
- Tao W-K, Simpson J (1993) The Goddard Cumulus Ensemble model. Part I: model description. Terr Atmos Ocean Sci 4:35–72Google Scholar
- Tao W-K, Simpson J, Sui C-H, Ferrier B, Lang S, Scala J, Chou M-D, Pickering K (1993) Heating, moisture and water budgets of tropical and midlatitude squall lines: comparisons and sensitivity to longwave radiation. J Atmos Sci 50:673–690Google Scholar