摘要
利用1959年1月—2008年12月的ECMWF ORA-S3资料,系统研究了印度洋塞舌尔穹隆区不同季节海表面温度(SST)的年际变化特征及其与ENSO、印度洋偶极子、穹隆区的温跃层深度/海面风应力、印尼贯穿流的关系。结果表明,穹隆区的SST在5—6月存在最明显的异常闭合中心(5月的中心值还较热带印度洋其它区域大),而在8—11月最不明显;区域平均的SST年际异常在2月最大,在8—9月最小。一般而言,北半球秋冬季和次年春季的穹隆区SST正(负)异常对应El Nio(La Nia)年或正(负)的印度洋偶极子年,但也有例外,北半球夏季尤其如此。相关分析表明,11月至次年7月(尤其是5月)深(浅)的温跃层对应穹隆区高(低)的SST;而11月至次年3和5月的Ekman抽吸减弱(增强)时,次年1—6月和8月的穹隆区SST升高(降低),其中Ekman抽吸中的2项在总体上起相反作用,但除了对2和8月的SST,风应力旋度项的贡献都占优;风应力大小(蒸发)主要影响10月至次年6月的SST(负相关);当1—2月向北的Ekman输送弱(强)或7—8月向南的Ekman输送强(弱)时,穹隆区的SST高(低);而8—11月的印尼贯穿流流量增大(减小)时,直至次年上半年的穹隆区SST皆升高(降低)。可见无论是穹隆区SST的年际变化本身还是它与不同物理过程/影响因子的关系均存在明显的季节差异性。
Based on ECMWF ORA-S3 data from January 1959 to December 2008,the interannual variability of sea surface temperature（SST）in the Seychelles Dome（SD）region of the Indian Ocean,as well as the relationship among SST and ENSO,the Indian Ocean dipole（IOD）,the thermocline depth and sea surface wind stress in SD,and the Indonesia throughflow are comprehensively studied.It is showed that the SST anomaly（SSTA）in SD exhibits the most obviously close center patterns in May to June（the central SSTA in May is larger than any other region of the tropicae Indion Ocean）and the most not obviously ones in August to November.The regional mean SSTA is maximum in February and minimum in August-September.Basically,positive（negative）SSTA in SD from boreal autumn-winter to spring next year occurred in El Nino（La Nina）years or positive（negative）IOD years,with some exceptions especially in boreal summer.Correlation analysis showed that deeper（shallower）thermocline in November to July next year（especially in May）corresponds to higher（lower）SST in SD;Weaker（stronger）Ekman pumping in November to March next year and May next year causes the increase（decrease）of SST during January through June next year and in August next year.A further investigation showed that the two terms in Ekman pumping plays an opposite role in the variability of SST in SD but the wind stress curl is dominant except for the SST in February and August;The magnitude of wind stress（evaporation）mainly affects SST from October to June next year（negative correlation）;Weaker（stronger）northward Ekman transports in January to February or stronger（weaker）southward Ekman transports in July to August will lead to higher（lower）SST in SD;While larger（smaller）volume transport of Indonesia throughflow in August to November cause the increase（decrease）of SST until to the first half of next year.It is evident that both the interannual variability of the SST in SD and its relationship with different physical pr
出处
《中国海洋大学学报（自然科学版）》
CAS
CSCD
北大核心
2016年第1期8-17,共10页
Periodical of Ocean University of China
基金
高等学校博士学科点专项科研基金项目(20110132110016)资助~~
