摘要
根据1955-2003年次表层海温、海洋上层400m热含量和混合层深度资料，采用EOF分析方法，研究热带太平洋-印度洋上层海温、热含量和混合层深度的年变化特征及其与厄尔尼诺、印度洋偶极子、热带辐合带分布和活动的关系。结果表明：海表温度SST的分布和变化不能代表海洋上层热含量的分布和变化，热含量HST的分布与混合层MLD分布比较相似，尤其在热带印度洋和东太平洋，MLD季节变化比HST和SST提前2～3个月左右。太平洋10°N附近HST带状强扰动区和赤道地区HST反相变化是热带太平洋上层海水温度扰动最主要特征。HST的强扰动区主要由60-300m次表层海温距平的扰动引起，80m左右扰动最强，这种扰动沿着斜温层由上向下，自东向西传递，上半年增温，下半年降温，具有明显的年周期变化。这种变化对ENSO循环期间热含量异常信号传播的影响值得关注。热带太平洋HST的扰动变化和太平洋的ITCZ和SPCZ的移动和变化也有一定的关联。印度洋的西北部和东南部次表层海温距平呈年周期的反相振荡，但这种固有振荡和印度洋偶极子DMI振荡反相，这可能是导致印度洋大部分偶极子生命史都很短的原因之一。
Annual variation characteristics of subsurface temperature, HST and MLD over the Tropical Pacific-Indian Ocean and the relationship between the characteristics and ENSO, Indian Ocean dipole and ITCZ are studied by applying the subsurface temperature, HST and MLD data from 1955 to 2003, using the method of EOF. The results show some important facts. 1. The distribution and variation of SST are incompatible with those of HST＇s but the distribution and variation of HST and MLD are similar. 2. There is a strong disturbance belf of HST near 10°N over Pacific Ocean and the disturbance of HST changes with the one over equator. 3. The strong disturbance of HST is caused by the disturbance of subsurface temperature of 60m to 300m under the ocean surface. The temperature disturbance is strongest on the 80m layer which transfers down and west along thermocline and the temperature rises in the first half year and declines in the next half. 4. The variation of HST disturbance over tropical Pacific Ocean is related to the moving and change of ITCZ and SPCZ over Pacific Ocean. 5. The subsurface temperature departure over northwest area and southeast area of Indian Ocean has an out-of-phase annual periodic oscillation which is opposite to the oscillation of Indian Ocean dipole.
出处
《海洋预报》
2006年第B09期47-59,共13页
Marine Forecasts
