Tracing Riverine Inputs and Ventilation Processes of the Upper Arctic by Means of Submarine Mounted On-Line Chemical Sensors

该项目包括开发用于美国海军潜艇的扫描光纤光谱仪，以及分析在北冰洋不同地区获得的水样，以确定河流携带的微量元素和污染物的扩散过程。先前的结果，使用保守的示踪剂，提供了一些河流影响的综合措施，但空间覆盖还不足以描绘淡水输入的途径。此外，已经使用的示踪剂，如碱度、钙和氧同位素，不能用来区分不同的河流来源。该项目将扩展现有的示踪剂套件，包括腐植酸和少量成分，如锰、钡、铷、锶、溴和碘。锰是一种特别有用的示踪剂，因为它在河流中的浓度通常比其在海洋中的浓度高两个数量级，而且这种浓度对河流化学和环境条件很敏感。因此，可以期望溶解的锰有助于提供特定的河流特征，并提供关于给定河流羽流分散特征的信息。＊＊＊

This project consists of the development of a scanning fiber optic spectrometer for use aboard a U.S. Navy submarine, and the analysis of water samples obtained in various parts of the Arctic Ocean in order to determine dispersion processes of river-borne trace elements and pollutants. Prior results, using conservative tracers, have provided some integrated measures of riverine influence, but the spatial coverage has not been sufficient to delineate the pathways of freshwater inputs. Furthermore the tracers that have been used, such as alkalinity, calcium, and oxygen isotopes, cannot be used to distinguish among different river sources. This project will extend the suite of available tracers to include humic acid and minor constituents such as manganese, barium, rubidium, strontium, bromine, and iodine. Manganese is a particularly useful tracer since its concentration in river water is typically two orders of magnitude greater than its open ocean value, and this concentration is sensitive to river chemistry and environmental conditions. Dissolved manganese can therefore be expected to help provide a particular river signature, and provide information on the dispersion characteristics of a given river plume. ***