A general form of an equation that 'explicitly' diagnoses SST change is derived. All other equations in wide use are its special case. Combining with the data from an ocean general circulation model (MOM2) wit...A general form of an equation that 'explicitly' diagnoses SST change is derived. All other equations in wide use are its special case. Combining with the data from an ocean general circulation model (MOM2) with an integration of 10 years (1987-1996), the relative importances of various processes that determine seasonal variations of SST in the tropical Indian Ocean are compared mainly for January, April, July and October. The main results are as follows. (1) The net surface heat flux is the most important factor affecting SST over the Arabian Sea, the Bay of Bengal and the region south of the equator in January; in April, its influence covers almost the whole region studied; whereas in July and October, this term shows significance only in the regions south of 10°S and north of the equator, respectively. (2) The horizontal advection dominates in the East African-Arabian coast and the region around the equator in January and July; in October, the region is located south of 10°S. (3) The entrainment is significant only in a narrow band centered on 10°S in April and the coastal region around the Arabian Sea and the equator in July. (4) As for SST, it decreases in January and July but increases in April and October in the Arabian Sea and the Bay of Bengal, showing a (asymmetrical) semiannual variability; by contrast, the SST in the region south of the equator has an annual variability, decreasing in April and July and increasing in October and January.展开更多
The shallow meridional overturning circulation (upper 1000 m) in the northern Indian Ocean and its interannual variability are studied, based on a global ocean circulation model (MOM2) with an integration of 10 years ...The shallow meridional overturning circulation (upper 1000 m) in the northern Indian Ocean and its interannual variability are studied, based on a global ocean circulation model (MOM2) with an integration of 10 years (1987-1996). It is shown that the shallow meridional overturning circulation has a prominent seasonal reversal characteristic. In winter, the flow is northward in the upper layer and returns southward at great depth. In summer, the deep northward inflow upwells north of the equator and returns southward in the Ekman layer. In the annual mean, the northward inflow returns through two branches: one is a southward flow in the Ekman layer, the other is a flow that sinks near 10°N and returns southward between 500 m and 1000 m. There is significant interannual variability in the shallow meridional overturning circulation, with a stronger (weaker) one in 1989 (1991) and with a period of about four years. The interannual variability of the shallow meridional overturning circulation is intimately r展开更多
基金This study was supported by the Key Program of the National Natural Science Foundation of China(NSFC)under Grant No.40233033.
文摘A general form of an equation that 'explicitly' diagnoses SST change is derived. All other equations in wide use are its special case. Combining with the data from an ocean general circulation model (MOM2) with an integration of 10 years (1987-1996), the relative importances of various processes that determine seasonal variations of SST in the tropical Indian Ocean are compared mainly for January, April, July and October. The main results are as follows. (1) The net surface heat flux is the most important factor affecting SST over the Arabian Sea, the Bay of Bengal and the region south of the equator in January; in April, its influence covers almost the whole region studied; whereas in July and October, this term shows significance only in the regions south of 10°S and north of the equator, respectively. (2) The horizontal advection dominates in the East African-Arabian coast and the region around the equator in January and July; in October, the region is located south of 10°S. (3) The entrainment is significant only in a narrow band centered on 10°S in April and the coastal region around the Arabian Sea and the equator in July. (4) As for SST, it decreases in January and July but increases in April and October in the Arabian Sea and the Bay of Bengal, showing a (asymmetrical) semiannual variability; by contrast, the SST in the region south of the equator has an annual variability, decreasing in April and July and increasing in October and January.
基金This study was supported by National Natural Science Foundation of China(NSFC)under Grant No.40233033.
文摘The shallow meridional overturning circulation (upper 1000 m) in the northern Indian Ocean and its interannual variability are studied, based on a global ocean circulation model (MOM2) with an integration of 10 years (1987-1996). It is shown that the shallow meridional overturning circulation has a prominent seasonal reversal characteristic. In winter, the flow is northward in the upper layer and returns southward at great depth. In summer, the deep northward inflow upwells north of the equator and returns southward in the Ekman layer. In the annual mean, the northward inflow returns through two branches: one is a southward flow in the Ekman layer, the other is a flow that sinks near 10°N and returns southward between 500 m and 1000 m. There is significant interannual variability in the shallow meridional overturning circulation, with a stronger (weaker) one in 1989 (1991) and with a period of about four years. The interannual variability of the shallow meridional overturning circulation is intimately r
