The North Equatorial Countercurrent(NECC) is an important zonal fl ow in the upper circulation of the tropical Pacifi c Ocean, which plays a vital role in the heat budget of the western Pacifi c warm pool. Using satel...The North Equatorial Countercurrent(NECC) is an important zonal fl ow in the upper circulation of the tropical Pacifi c Ocean, which plays a vital role in the heat budget of the western Pacifi c warm pool. Using satellite-derived data of ocean surface currents and sea surface heights(SSHs) from 1992 to 2011, the seasonal variation of the surface NECC in the western tropical Pacifi c Ocean was investigated. It was found that the intensity(INT) and axis position(Y_(CM)) of the surface NECC exhibit strikingly different seasonal fl uctuations in the upstream(128°–136°E) and downstream(145°–160°E) regions. Of the two regions, the seasonal cycle of the upstream NECC shows the greater interannual variability. Its INT and Y CM are greatly infl uenced by variations of the Mindanao Eddy, Mindanao Dome(MD), and equatorial Rossby waves to its south. Both INT and YC M also show semiannual signals induced by the combined effects of equatorial Rossby waves from the Central Pacifi c and local wind forcing in the western Pacifi c Ocean. In the downstream region, the variability of the NECC is affected by SSH anomalies in the MD and the central equatorial Pacifi c Ocean. Those in the MD region are especially important in modulating the Y CM of the downstream NECC. In addition to the SSH-related geostrophic fl ow, zonal Ekman fl ow driven by meridional wind stress also plays a role, having considerable impact on INT variability of the surface NECC. The contrasting features of the variability of the NECC in the upstream and downstream regions refl ect the high complexity of regional ocean dynamics.展开更多
全国大学生英语竞赛（National English Competition for College Students,简称NECCS）是经教育部有关部门批准，是由教育部高等学校大学外语教学指导委员会和高等学校大学外语教学研究会联合主办，天仁报业集团英语辅导报社、考试与...全国大学生英语竞赛（National English Competition for College Students,简称NECCS）是经教育部有关部门批准，是由教育部高等学校大学外语教学指导委员会和高等学校大学外语教学研究会联合主办，天仁报业集团英语辅导报社、考试与评价杂志社承办的全国唯一的大学生英语综合能力竞赛。展开更多
【赛题再现】
Everyone knows about pollution in the environment. Water, air, and land are all polluted. This means that pollution is everywhere. Now, scientists are looking inside our bodies to find out about interna...【赛题再现】
Everyone knows about pollution in the environment. Water, air, and land are all polluted. This means that pollution is everywhere. Now, scientists are looking inside our bodies to find out about internal pollution.展开更多
基金Supported by the National Natural Science Foundation of China(No.41276001)the Strategic Priority Research Program of Chinese Academy of Sciences(No.XDA11010201)+2 种基金the Global Change and Air-Sea Interaction Program(No.GASI-03-01-01-05)the National Basic Research Program of China(973 Program)(No.2012CB417401)the Scientific and Technological Development Plan Project of Shandong Province(No.2013GRC31503)
文摘The North Equatorial Countercurrent(NECC) is an important zonal fl ow in the upper circulation of the tropical Pacifi c Ocean, which plays a vital role in the heat budget of the western Pacifi c warm pool. Using satellite-derived data of ocean surface currents and sea surface heights(SSHs) from 1992 to 2011, the seasonal variation of the surface NECC in the western tropical Pacifi c Ocean was investigated. It was found that the intensity(INT) and axis position(Y_(CM)) of the surface NECC exhibit strikingly different seasonal fl uctuations in the upstream(128°–136°E) and downstream(145°–160°E) regions. Of the two regions, the seasonal cycle of the upstream NECC shows the greater interannual variability. Its INT and Y CM are greatly infl uenced by variations of the Mindanao Eddy, Mindanao Dome(MD), and equatorial Rossby waves to its south. Both INT and YC M also show semiannual signals induced by the combined effects of equatorial Rossby waves from the Central Pacifi c and local wind forcing in the western Pacifi c Ocean. In the downstream region, the variability of the NECC is affected by SSH anomalies in the MD and the central equatorial Pacifi c Ocean. Those in the MD region are especially important in modulating the Y CM of the downstream NECC. In addition to the SSH-related geostrophic fl ow, zonal Ekman fl ow driven by meridional wind stress also plays a role, having considerable impact on INT variability of the surface NECC. The contrasting features of the variability of the NECC in the upstream and downstream regions refl ect the high complexity of regional ocean dynamics.
文摘全国大学生英语竞赛（National English Competition for College Students,简称NECCS）是经教育部有关部门批准，是由教育部高等学校大学外语教学指导委员会和高等学校大学外语教学研究会联合主办，天仁报业集团英语辅导报社、考试与评价杂志社承办的全国唯一的大学生英语综合能力竞赛。
文摘【赛题再现】
Everyone knows about pollution in the environment. Water, air, and land are all polluted. This means that pollution is everywhere. Now, scientists are looking inside our bodies to find out about internal pollution.
