Details:

Journal Title:
Journal of Climate
Personal Author:
Jiang, Zhihong ; Huo, Fei ; Ma, Hongyun ; Song, Jie ; Dai, Aiguo
Jiang, Zhihong ; Huo, Fei ; Ma, Hongyun ; Song, Jie ; Dai, Aiguo Less -
NOAA Program & Office:
OAR (Oceanic and Atmospheric Research) ; CPO (Climate Program Office)
OAR (Oceanic and Atmospheric Research) ; CPO (Climate Program Office) Less -
Description:
Impacts of urbanization and anthropogenic aerosols in China on the East Asian summer monsoon (EASM) are investigated using version 5.1 of the Community Atmosphere Model (CAM5.1) by comparing simulations with and without incorporating urban land cover and/or anthropogenic aerosol emissions. Results show that the increase of urban land cover causes large surface warming and an urban frictional drag, both leading to a northeasterly wind anomaly in the lower troposphere over eastern China (EC). This weakens the southerly winds associated with the EASM and causes a convergence anomaly in southern China (SC) with increased ascent, latent heating, and cloudiness. The enhanced latent heating reinforces surface convergence and upper-level divergence over SC, leading to more northward advection in the upper level into northern China (NC) and descending between 30° and 50°N over East Asia. Cloudiness reduction, adiabatic heating, and warm advection over NC all enhance the urban heating there, together causing anomalous tropospheric warming at those latitudes over East Asia. Anthropogenic aerosols cause widespread cooling at the surface and in the troposphere over EC, which decreases the summer land–ocean thermal contrast, leading to a weakened EASM circulation with reduced moisture transport to NC. This results in wetter and drier conditions over SC and NC, respectively. When both the urbanization and anthropogenic aerosols are included in the model, aerosols’ cooling is partially offset by the urban heating, and their joint effect on the circulation is dominated by the aerosols’ effect with a reduced magnitude. In the combined experiment, surface and tropospheric temperatures are also altered by the decrease (increase) in cloudiness over NC (SC) with most of the cooling confined to SC, which further weakens the EASM circulation.
Keywords:
[+]
Climatic Changes—Effect Of Human Beings On Land Use Meteorology Monsoons Atmosphere-land Interaction Urban Meteorology
Source:
Journal of Climate, 30(3), 1019-1039
DOI:
https://doi.org/10.1175/JCLI-D-15-0593.1
Document Type:
Journal Article
Funding:
Grant no. NA15OAR4310086
Rights Information:
Other
Compliance:
Submitted
Main Document Checksum:
[+]
urn:sha256:869bacbac403109c35062a635351108d4e0ec0bd0ad1208d7f0af9b963d54f7a
Download URL:
https://repository.library.noaa.gov/view/noaa/28352/noaa_28352_DS1.pdf
File Type:

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