Impacts of Subgrid Orographic Drag on the Summer Monsoon Circulation and Precipitation in East Asia

AbstractThe regional coupled climate–chemistry/aerosol model (RegCM3) is used to investigate the difference in the spatial distribution of aerosol optical depth (AOD) between a strong summer monsoon year (SSMY; July 2003) and a weak summer monsoon year (WSMY; July 2002) under the actual- and same-emission scenarios. It is shown that the intensity of the Asian summer monsoon is primarily responsible for the AOD spatial distribution anomaly in midsummer over East Asia. Specifically, the AOD over southern China, upwind of the Asian summer monsoon, is greater in WSMY than in SSMY, but the opposite is observed for the AOD downwind over northern China and the Korean Peninsula. The AOD spatial distribution patterns simulated on the basis of the actual emission inventories for the SSMY and WSMY do not substantially differ from their counterparts that are based on the same emission inventory, confirming that the monsoon circulation, rather than local emissions or dry and wet deposition processes, is the predominant factor determining the regional AOD distribution. These modeling results are consistent with the analyses based on the Moderate Resolution Imaging Spectroradiometer (MODIS) products, NCAR–Department of Energy wind fields, and air parcel movements according to the 7-day trajectories of air parcels determined by the Hybrid Single-Particle Lagrangian Integrated Trajectory model.

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Historical flooding regime along the Amur River and its links to East Asia summer monsoon circulation

Geomorphology ◽

10.1016/j.geomorph.2021.107782 ◽

2021 ◽

pp. 107782

Author(s):

Zhenqing Zhang ◽

Qiang Yao ◽

Kam-biu Liu ◽

Lin Li ◽

Rui Yin ◽

...

Keyword(s):

East Asia ◽

Summer Monsoon ◽

Monsoon Circulation ◽

East Asia Summer Monsoon ◽

Amur River ◽

Flooding Regime ◽

The Amur River

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Reduction of systematic errors in regional climate simulations of the summer monsoon over East Asia and the western North Pacific by applying the spectral nudging technique

Journal of Geophysical Research Atmospheres ◽

10.1029/2008jd011176 ◽

2009 ◽

Vol 114 (D14) ◽

Cited By ~ 52

Author(s):

Dong-Hyun Cha ◽

Dong-Kyou Lee

Keyword(s):

East Asia ◽

Summer Monsoon ◽

North Pacific ◽

Western North Pacific ◽

Regional Climate ◽

Systematic Errors ◽

Spectral Nudging ◽

Climate Simulations

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Validation of the HIRHAM-Simulated Indian Summer Monsoon Circulation

Advances in Meteorology ◽

10.1155/2010/415632 ◽

2010 ◽

Vol 2010 ◽

pp. 1-14 ◽

Cited By ~ 15

Author(s):

Stefan Polanski ◽

Annette Rinke ◽

Klaus Dethloff

Keyword(s):

Summer Monsoon ◽

Climate Model ◽

Regional Climate ◽

Horizontal Resolution ◽

Monsoon Circulation ◽

Data Sets ◽

Data Set ◽

Topographic Features ◽

Temperature And Precipitation ◽

Simulated Precipitation

The regional climate model HIRHAM has been applied over the Asian continent to simulate the Indian monsoon circulation under present-day conditions. The model is driven at the lateral and lower boundaries by European reanalysis (ERA40) data for the period from 1958 to 2001. Simulations with a horizontal resolution of 50 km are carried out to analyze the regional monsoon patterns. The focus in this paper is on the validation of the long-term summer monsoon climatology and its variability concerning circulation, temperature, and precipitation. Additionally, the monsoonal behavior in simulations for wet and dry years has been investigated and compared against several observational data sets. The results successfully reproduce the observations due to a realistic reproduction of topographic features. The simulated precipitation shows a better agreement with a high-resolution gridded precipitation data set over the central land areas of India and in the higher elevated Tibetan and Himalayan regions than ERA40.

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