Upper tropospheric cloud-radiation interaction induced by monsoon surge over the South China Sea
We have investigated cloud formation over the South China Sea in the upper troposphere and its impacts on the radiation budget of the troposphere and ocean surface under monsoon surges using satellite and reanalysis products and an atmospheric numerical model. During strong surges (SS), the upper tr...
| Main Authors: | , , , |
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| Other Authors: | |
| Format: | Journal Article |
| Language: | English |
| Published: |
2024
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| Subjects: | |
| Online Access: | https://hdl.handle.net/10356/174562 |
| _version_ | 1811689378486943744 |
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| author | Koseki, Shunya Fonseca, Ricardo Koh, Tieh Yong Teo, Chee Kiat |
| author2 | College of Lifelong and Experimental Learning, SUSS |
| author_facet | College of Lifelong and Experimental Learning, SUSS Koseki, Shunya Fonseca, Ricardo Koh, Tieh Yong Teo, Chee Kiat |
| author_sort | Koseki, Shunya |
| collection | NTU |
| description | We have investigated cloud formation over the South China Sea in the upper troposphere and its impacts on the radiation budget of the troposphere and ocean surface under monsoon surges using satellite and reanalysis products and an atmospheric numerical model. During strong surges (SS), the upper tropospheric (UT) cloud formation in central South China Sea shows a clear diurnal cycle, peaking around 12–14 local solar time when the incoming solar radiation is the strongest. The enhanced UT clouds attenuate the incoming solar radiation in the upper troposphere reducing the net downward shortwave radiation flux at the surface by approximately 28% in SS compared with no surge case. In contrast the downward longwave radiation flux is enhanced mainly from the middle to upper troposphere in SS. The cooling because of the diminished incoming shortwave radiation overwhelms the warming due to the longwave radiation at the ocean surface. This cloud radiative forcing is observed partly over the cold tongue in sea surface temperature (SST) in the South China Sea. Numerical simulations with a 1-dimensional slab ocean model suggests that the monsoon-induced UT cloud radiative forcing contributes partially to maintain and reinforce the SST cold tongue with a tendency of about 0.08 K in 6 days or about 1/6 of one standard deviation of the Cold Tongue Index in December. The latent heat flux due to the monsoon surge is still the most significant factor maintaining the cold tongue. |
| first_indexed | 2024-10-01T05:47:09Z |
| format | Journal Article |
| id | ntu-10356/174562 |
| institution | Nanyang Technological University |
| language | English |
| last_indexed | 2024-10-01T05:47:09Z |
| publishDate | 2024 |
| record_format | dspace |
| spelling | ntu-10356/1745622024-04-02T15:36:51Z Upper tropospheric cloud-radiation interaction induced by monsoon surge over the South China Sea Koseki, Shunya Fonseca, Ricardo Koh, Tieh Yong Teo, Chee Kiat College of Lifelong and Experimental Learning, SUSS Centre for Climate Research Singapore, Meteorological Services Singapore Earth Observatory of Singapore Temasek Laboratories @ NTU Earth and Environmental Sciences Climate change impacts Extreme rainfall We have investigated cloud formation over the South China Sea in the upper troposphere and its impacts on the radiation budget of the troposphere and ocean surface under monsoon surges using satellite and reanalysis products and an atmospheric numerical model. During strong surges (SS), the upper tropospheric (UT) cloud formation in central South China Sea shows a clear diurnal cycle, peaking around 12–14 local solar time when the incoming solar radiation is the strongest. The enhanced UT clouds attenuate the incoming solar radiation in the upper troposphere reducing the net downward shortwave radiation flux at the surface by approximately 28% in SS compared with no surge case. In contrast the downward longwave radiation flux is enhanced mainly from the middle to upper troposphere in SS. The cooling because of the diminished incoming shortwave radiation overwhelms the warming due to the longwave radiation at the ocean surface. This cloud radiative forcing is observed partly over the cold tongue in sea surface temperature (SST) in the South China Sea. Numerical simulations with a 1-dimensional slab ocean model suggests that the monsoon-induced UT cloud radiative forcing contributes partially to maintain and reinforce the SST cold tongue with a tendency of about 0.08 K in 6 days or about 1/6 of one standard deviation of the Cold Tongue Index in December. The latent heat flux due to the monsoon surge is still the most significant factor maintaining the cold tongue. Published version 2024-04-02T07:55:13Z 2024-04-02T07:55:13Z 2023 Journal Article Koseki, S., Fonseca, R., Koh, T. Y. & Teo, C. K. (2023). Upper tropospheric cloud-radiation interaction induced by monsoon surge over the South China Sea. Meteorological Applications, 30(2). https://dx.doi.org/10.1002/met.2125 1350-4827 https://hdl.handle.net/10356/174562 10.1002/met.2125 2-s2.0-85153888117 2 30 en Meteorological Applications © 2023 The Authors. Meteorological Applications published by John Wiley & Sons Ltd on behalf of the Royal Meteorological Society. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. application/pdf |
| spellingShingle | Earth and Environmental Sciences Climate change impacts Extreme rainfall Koseki, Shunya Fonseca, Ricardo Koh, Tieh Yong Teo, Chee Kiat Upper tropospheric cloud-radiation interaction induced by monsoon surge over the South China Sea |
| title | Upper tropospheric cloud-radiation interaction induced by monsoon surge over the South China Sea |
| title_full | Upper tropospheric cloud-radiation interaction induced by monsoon surge over the South China Sea |
| title_fullStr | Upper tropospheric cloud-radiation interaction induced by monsoon surge over the South China Sea |
| title_full_unstemmed | Upper tropospheric cloud-radiation interaction induced by monsoon surge over the South China Sea |
| title_short | Upper tropospheric cloud-radiation interaction induced by monsoon surge over the South China Sea |
| title_sort | upper tropospheric cloud radiation interaction induced by monsoon surge over the south china sea |
| topic | Earth and Environmental Sciences Climate change impacts Extreme rainfall |
| url | https://hdl.handle.net/10356/174562 |
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