本文利用区域海气耦合模式FROALS(Flexible Regional Ocean-Atmosphere-Land System)对西北太平洋地区1984-2007年连续积分结果,对比SODA(Simple Ocean Data Assimilation)同化资料讨论了西北太平洋海表温度和表层洋流的气候态及年际变率。结果表明,FROALS基本能够再现冬、夏季季节平均的海温型,但均存在一个明显的冷偏差;FROALS对气候平均态的表层洋流有较高的模拟技巧,对于冬、夏季的表层洋流型都能够再现。另外,表层洋流的模拟偏差与海表高度的模拟偏差直接相关。由于模式模拟的黑潮热输送较观测偏强,使得模式模拟的海洋热输送倾向于使黑潮路径上的海温呈现正偏差。从表层洋流的年际变率来看,模式模拟的与ENSO(El Nio-South Oscillation)相联系的年际变率信号与观测相似:在El Nio年,北赤道流和棉兰老流增强,低纬度西太平洋海表高度降低,而在La Nia年则呈现出相反的形态,但是在模式中这种信号稍强于观测。
The authors evaluated the performance of a regional ocean-atmosphere coupled model (FROALS) in the sim- ulation of the surface circulation and its interannual variability during 1984- 2002 over the northwestern Pacific. FROALS well reproduced the mean state of sea surface temperature but with an obvious cold bias. The climatology of surface currents and its inter-annual variability are reproduced reasonably for both summer and winter. The bias of simulated surface circulation is mainly associated with the sea surface height bias. Due to stronger heat transport by Kuroshio in FROALS,the warm bias of simulated sea surface temperature was found along Kuroshio path. For inter- annual variability of surface currents,the ENSOrelated inter-annual signal was well reproduced in FROALS. During E1 Nifio years, North Equatorial Current (NEC) and Mindanao Current (MC) were stronger, while sea surface height of low-latitude western Pacific were lower than normal years; during La Nifia years it showed opposite pattern. The discrepancy was that the inter-annual signal in FROALS is stronger than observation.