LOOP Current variability - its relation to meridional overturning circulation and the impact of Mississippi discharge

LOOP 电流变化 - 其与经向翻转环流的关系以及密西西比河泄流的影响

• 批准号: 42144659
• 负责人: Professor Dr. Dirk Nürnberg
• 金额: --
• 依托单位: Alfred-Wegener-Institut (AWI) Helmholtz-Zentrum für Polar- und Meeresforschung
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 财政年份: 2007
• 资助国家: 德国
• 起止时间: 2006-12-31 至 2013-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/42144659?language=en
• 关键词: LOOP; Current; variability; its; relation

The Loop Current and its associated eddy-shedding is mediating the oceanic heat and salt flux from the Caribbean into the Atlantic Ocean. Its interference with Mississippi discharge are critical for both, regional climate in the Gulf of Mexico and large-scale transports towards high northern latitudes. By combining state-of-the-art paleoceanographic and meso-scale eddy-resolving numerical modeling techniques, we examine the Loop Current dynamics and hydrographic changes in the Gulf during the last deglaciation and interglacials MIS 1 and 5 with a special focus on the impact of Mississippifreshwater discharge.Deglacial SST and SSS changes in the Gulf appear to be rather continuous and significantly larger than in the Caribbean/Atlantic Warmpool. Surface freshening occurs during glacial periods and deglacial cool events and is related to enhanced and eastward directed Mississippi river discharge. In this project, we relate the continuous and stronger deglacial surface warming in the Gulf to the onset and increase of eddy-shedding by the Loop Current related to deglacial sea level rise, Yucatan Strait throughflow velocity, and changes in the atmospheric circulation. Further, we investigate enhancedfluvial discharge on the circulation in the Gulf of Mexico.

环流和与之相关的漩涡脱落调节着从加勒比海到大西洋的海洋热盐通量。它对密西西比河排放的干扰对墨西哥湾的区域气候和向北纬高纬度地区的大规模运输都至关重要。通过结合最先进的古海洋学和中尺度漩涡解析数值模拟技术，我们研究了墨西哥湾在最后一次消冰期和间冰期MIS 1和MIS 5期间的环流动力学和水文变化，并特别关注密西西比淡水排放的影响。墨西哥湾的冰期海温和海温的变化似乎是相当连续的，并且明显大于加勒比海/大西洋暖池。地表清新作用发生在冰期和去冰期的冷事件中，并与密西西比河流量的增强和向东方向有关。在本项目中，我们将墨西哥湾持续和强烈的消冰表面变暖与消冰海平面上升、尤卡坦海峡通流速度和大气环流变化相关的环流脱落的发生和增加联系起来。此外，我们还研究了墨西哥湾环流中河流流量的增强。