Ages of River Plumes and Freshened Coastal Waters Using Ra-224 and Ra-223

9314587摩尔这个研究项目将使用短寿命的镭同位素来确定淡水的年龄，因为这些水从沿海地区移动和混合到公海。这些技术将使海洋科学家能够在几天到几周的时间尺度上追踪沿海水域的运动和混合。这些研究将为沿海海洋与海洋和海洋内部之间的耦合提供重要信息。当与其他研究相结合时，这些技术将使海洋学家能够评估物质在密度梯度上的通量，密度梯度将新鲜的沿海水域与其他表层海洋分开。这项工作是基于一种新的短寿命Ra同位素测量技术，224 Ra（半衰期= 3.6天）和223 Ra（半衰期= 11.4天）。最初的大部分工作将用于技术开发和验证。然后，实地研究将确定(1)密西西比河的淡水流侵入墨西哥湾的速度；(2)从近海岸水域穿过南大西洋湾的内部和中部大陆架区域的混合速度。

9314587 MOORE This research project will use short lived radium isotopes to determine the ages of freshened waters as these waters move and mix from the coastal zone into the open ocean. These techniques should enable marine scientists to tract the movement and mixing of coastal waters on time scales of a few days to several weeks. These studies will provide important information on the coupling between the coastal ocean and the ocean and the ocean interior. When combined with other studies, these techniques will enable oceanographers to assess fluxes of materials across the density gradient separating freshened coastal waters from the rest of the surface ocean. This work is based on a new measurement technique for short lived Ra isotopes, 224 Ra (half life = 3.6 days) and 223 Ra (half life = 11.4 days). Most of the effort will be devoted to technique development and verification initially. Field Studies will then determine (1) the rate at which the freshened river plume of the Mississippi River intrudes into the Gulf of Mexico and (2) the rate of mixing from near coastal waters across the inner and mid shelf region of the south Atlantic Bight.