Atmosphere–Ocean Coupled Process along Coastal Areas of the Yellow and East China Seas in Winter

• Published in: Journal of climate Vol. 27; no. 1; pp. 155 - 167
• Main Authors: Iwasaki, Shinsuke, Isobe, Atsuhiko, Kako, Shin'ichiro
• Format: Journal Article
• Language: English
• Published: Boston, MA American Meteorological Society 01.01.2014
• Subjects: Asian; Atmosphere; Atmospheric boundary layer; Atmospheric models; Atmospheric research; Atmospherics; Boundary conditions; Buoys; China; Coastal environments; Coastal processes; Coastal water; Coastal waters; Coastal zone; Coasts; Cyclones; Dry air; Drying; Earth, ocean, space; Exact sciences and technology; External geophysics; Heat; Heat flux; Heat loss; Heat transfer; Horizontal; Marine; Meteorology; Modelling; Negative feedback; Ocean circulation; Ocean currents; Ocean models; Oceans; Physics of the oceans; Regional development; Satellite observation; Satellites; Sea level; Sea level pressure; Sea surface; Sea surface temperature; Sea-air exchange processes; Seas; Shallow water; Surface temperature; Topography; Wind; Wind speed; Wind velocity; Winds; Winter; Pacific Ocean; West Pacific; Northwest Pacific; East China Sea; Yellow Sea; North Pacific; China; Japan; INW, Donghai Sea; Ocean-atmosphere model; coastal zone; Coupled model; Winter; Space remote sensing; Observation data; Satellite observation; digital simulation; Sea surface temperature; ocean-atmosphere interaction; Comparative study
• ISSN: 0894-8755; 1520-0442
• DOI: 10.1175/jcli-d-13-00117.1

A regional atmosphere–ocean coupled model is developed, based on the Pennsylvania State University–National Center for Atmospheric Research Mesoscale Model in conjunction with the Princeton Ocean Model, to investigate atmosphere–ocean coupled processes that might occur over the Yellow and East China Sea shelves in winter. To examine how the coupled processes actually work in the ocean, sea surface temperatures (SSTs) computed in both coupled and uncoupled models are compared with SSTs synthesized from multiple satellite observations. The results indicate that the coupled model significantly improves the negative SST bias in shallow waters around the Chinese coast produced by the uncoupled model. Cool and dry northerly winds from the Asian landmass reduce SST in these shallow waters through intensive upward heat loss. Thereafter, the horizontal gradient of sea level pressure (SLP) around the Chinese coast moderates because the land–ocean heat contrast weakens owing to the reduced SST in the coastal waters. As a result, the wind speed weakens, in line with the moderated horizontal SLP gradient. Moreover, northerly winds can reduce the transport of cool and dry air from the Asian landmass. Hence, upward heat flux around the coastal waters is reduced because of the weakening of the northerly winds and the decreased cool and dry air. This negative feedback thereby suppresses excessive SST cooling along the Chinese coast during winter.