Abstract
This study evaluates the sensitivity of summertime rainfall simulations over East-to-southeast Asia and the western north Pacific in the regional climate model version 4 (RegCM4) to cumulus (including Grell with Arakawa–Schubert type closure, Grell with Fritsch–Chappell type closure, and Emanuel), land surface (Biosphere– atmosphere transfer scheme or BATS, and the community land model or CLM) and ocean surface (referred to as Zeng1, Zeng2 and BATS1e in the model) schemes by running the model with different combinations of these parameterization packages. For each of these experiments, ensemble integration of the model was carried out in the extended boreal summer of May–October from 1998 to 2007. The simulated spatial distribution, intensity and interannual variation of the precipitation, latent heat flux, position of the subtropical high and tropical cyclone genesis patterns from these numerical experiments were analyzed. Examinations show that the combination of Emanuel, CLM and Zeng2 (E-C-Z2) yields the best overall results, consistent with the fact that physical mechanisms considered in E-C-Z2 tend to be more comprehensive in comparison with the others. Additionally, the rainfall quantity is found very sensitive to sea surface roughness length, and the reduction of the roughness length constant (from 2 × 10−4 to 5 × 10−5 m) in our modified BATS1e mitigates the drastic overestimation of latent heat flux and rainfall, and is therefore preferable to the default value for simulations in the western north Pacific region in RegCM4.
| Original language | English |
|---|---|
| Pages (from-to) | 2487-2505 |
| Number of pages | 19 |
| Journal | Climate Dynamics |
| Volume | 46 |
| Issue number | 7-8 |
| DOIs | |
| Publication status | Published - 2016 Apr |
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Keywords
- Cumulus scheme
- Land surface model
- Ocean surface scheme
- Precipitation
- Regional climate model
ASJC Scopus subject areas
- Atmospheric Science
Cite this
Evaluating the impacts of cumulus, land surface and ocean surface schemes on summertime rainfall simulations over East-to-southeast Asia and the western north pacific by RegCM4. / Li, Yu Bin; Tam, Chi Yung; Huang, Wan Ru; Cheung, Kevin K.W.; Gao, Zhiqiu.
In: Climate Dynamics, Vol. 46, No. 7-8, 04.2016, p. 2487-2505.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Evaluating the impacts of cumulus, land surface and ocean surface schemes on summertime rainfall simulations over East-to-southeast Asia and the western north pacific by RegCM4
AU - Li, Yu Bin
AU - Tam, Chi Yung
AU - Huang, Wan Ru
AU - Cheung, Kevin K.W.
AU - Gao, Zhiqiu
PY - 2016/4
Y1 - 2016/4
N2 - This study evaluates the sensitivity of summertime rainfall simulations over East-to-southeast Asia and the western north Pacific in the regional climate model version 4 (RegCM4) to cumulus (including Grell with Arakawa–Schubert type closure, Grell with Fritsch–Chappell type closure, and Emanuel), land surface (Biosphere– atmosphere transfer scheme or BATS, and the community land model or CLM) and ocean surface (referred to as Zeng1, Zeng2 and BATS1e in the model) schemes by running the model with different combinations of these parameterization packages. For each of these experiments, ensemble integration of the model was carried out in the extended boreal summer of May–October from 1998 to 2007. The simulated spatial distribution, intensity and interannual variation of the precipitation, latent heat flux, position of the subtropical high and tropical cyclone genesis patterns from these numerical experiments were analyzed. Examinations show that the combination of Emanuel, CLM and Zeng2 (E-C-Z2) yields the best overall results, consistent with the fact that physical mechanisms considered in E-C-Z2 tend to be more comprehensive in comparison with the others. Additionally, the rainfall quantity is found very sensitive to sea surface roughness length, and the reduction of the roughness length constant (from 2 × 10−4 to 5 × 10−5 m) in our modified BATS1e mitigates the drastic overestimation of latent heat flux and rainfall, and is therefore preferable to the default value for simulations in the western north Pacific region in RegCM4.
AB - This study evaluates the sensitivity of summertime rainfall simulations over East-to-southeast Asia and the western north Pacific in the regional climate model version 4 (RegCM4) to cumulus (including Grell with Arakawa–Schubert type closure, Grell with Fritsch–Chappell type closure, and Emanuel), land surface (Biosphere– atmosphere transfer scheme or BATS, and the community land model or CLM) and ocean surface (referred to as Zeng1, Zeng2 and BATS1e in the model) schemes by running the model with different combinations of these parameterization packages. For each of these experiments, ensemble integration of the model was carried out in the extended boreal summer of May–October from 1998 to 2007. The simulated spatial distribution, intensity and interannual variation of the precipitation, latent heat flux, position of the subtropical high and tropical cyclone genesis patterns from these numerical experiments were analyzed. Examinations show that the combination of Emanuel, CLM and Zeng2 (E-C-Z2) yields the best overall results, consistent with the fact that physical mechanisms considered in E-C-Z2 tend to be more comprehensive in comparison with the others. Additionally, the rainfall quantity is found very sensitive to sea surface roughness length, and the reduction of the roughness length constant (from 2 × 10−4 to 5 × 10−5 m) in our modified BATS1e mitigates the drastic overestimation of latent heat flux and rainfall, and is therefore preferable to the default value for simulations in the western north Pacific region in RegCM4.
KW - Cumulus scheme
KW - Land surface model
KW - Ocean surface scheme
KW - Precipitation
KW - Regional climate model
UR - http://www.scopus.com/inward/record.url?scp=84936802355&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84936802355&partnerID=8YFLogxK
U2 - 10.1007/s00382-015-2714-y
DO - 10.1007/s00382-015-2714-y
M3 - Article
AN - SCOPUS:84936802355
VL - 46
SP - 2487
EP - 2505
JO - Climate Dynamics
JF - Climate Dynamics
SN - 0930-7575
IS - 7-8
ER -