IMPACT OF ENSO AND INDIAN OCEAN DIPOLE MODE (IODM) ON VARIABILITY OF THE OCEANOGRAPHIC PROCESSES IN THE EASTERN TROPICAL INDIAN OCEAN.

1999年，印度洋偶极子模（IODM）在印度洋被发现。这一现象与强烈的厄尔尼诺现象同时发生，并将印度洋赤道地区的东半部变成了一个上升流状态，持续了几个月。这些发现使东热带印度洋区域成为一个具有重大气候意义的地区。该项目的目的是利用1997年9月至2003年12月的多传感器遥感时间序列数据，即海面高度（SSH）、海洋表面风、海面温度（SST）和浮游植物色素浓度（叶绿素a），了解热带印度洋东部上升流现象的季节演变和年际变化。我们的研究重点是监测IODM和ENSO对该地区中尺度物理-生物海洋学过程的影响。结果表明，热带印度洋东部的海温变率、SSH距平和海温异常最大， 关于我们 在1997-98年同时发生的强厄尔尼诺和IODM事件期间，此外，有一个显着的偏离7年每月叶绿素气候的幅度和时间的季节响应东南季风。在1997-98年厄尔尼诺和IODM的高峰期，异常东风诱导强烈的上升流，并解除温跃层的深度比气候平均值沿着爪哇海岸导致较高的叶绿素a浓度和随后的高叶绿素a区域沿沿着苏门答腊海岸向西北延伸。在1997年底，1998年初和1999年底连续发生的异常海洋条件被认为是一致的IODM的进化模式较早报道。我们的研究结果突出了多传感器遥感数据的有用性，为气候事件和生物海洋学过程之间的相互作用提供了重要的见解，并有助于促进我们对该地区生物生产机制和远洋渔业的理解。少

In 1999, Indian Ocean Dipole Mode (IODM) was discovered in the Indian Ocean. This phenomenon co-occurred with a strong El Nino event and transformed eastern half of the Indian Ocean equatorial region into an upwelling regime for several months. Such findings made the eastern tropical Indian Ocean region an area of major climatic importance. The purpose of this project is to understand the seasonal evolution and interannual variability of the upwelling phenomena in the eastern tropical Indian Ocean using multi-sensor remote sensing time series data i.e. sea-surface height (SSH), ocean surface winds, sea-surface temperature (SST) and phytoplankton pigment concentration (chlorophyll a) from September 1997 to December 2003. The focus of our research is to monitor impact of the IODM and ENSO on mesoscale physical-biological oceanographic processes in the region. Our results indicated that the eastern tropical Indian Ocean exhibits the largest SST variability, SSH anomaly and the strongest w … More inds during simultaneous occurrence of a strong El Nino and IODM events in 1997-98. Furthermore, there was a significant departure from the 7-year monthly chlorophyll climatology in both magnitude and timing of seasonal response to the SE monsoon. During the peak of the 1997-98 El Nino and IODM, anomalous easterly wind induced strong upwelling and lifted the thermocline to depths much shallower than the climatological mean along the coast of Java resulting higher chlorophyll a concentration and subsequently the high chlorophyll a area extended northwestward along the Sumatra coast. Sequential occurrence of anomalous ocean condition during late-1997, early-1998 and late-1999 was found to be consistent with the evolutionary pattern of the IODM reported earlier. Our results highlight usefulness of multi-sensor remote sensing data in providing significant insight into strong interplay between climatological events and biological oceanographic processes and contribute to furtherance of our understanding of biological production mechanism and pelagic fisheries in the region. Less