Terrestrial rivers are a well-known part of the global water cycle, and there has been recent discussion of "atmospheric rivers" that transport vast quantities of moisture from the tropical ocean to mid-latitudes in transient weather systems. Complementary "salt rivers" within the ocean are an equally important part of the global water cycle. They help define the ocean's methods of returning water to where it is needed to maintain sea level and the global water cycle. One part of the Salinity Processes in the Upper-ocean Regional Study (SPURS) focused on the North Atlantic surface salinity maximum, where high evaporation rates remove freshwater from the ocean surface and leave dissolved salts behind. Much of the effort is devoted to understanding how that salty water disperses through lateral and vertical mixing processes. One important exit path is simple advection within the general circulation, which in the central Atlantic means the wind-driven "Sverdrup" circulation. Evaporation results in high salinity within the flow, marking a subsurface salt river within the ocean. Here, we examine the river's structure as revealed in the average salinity field of the North Atlantic. Mid-ocean salinity maxima provide a unique opportunity to use an isohaline control volume approach for analyzing the mixing processes that disperse the high-salinity plume.

Tropical cyclone intensity is strongly affected by the air‐sea heat flux beneath the storm. When strong storm winds enhance upper ocean turbulent mixing and entrainment of colder water from below the thermocline, the resulting sea surface temperature cooling may reduce the heat flux to the storm and weaken the storm. Recent studies suggest that this upper ocean turbulence is strongly affected by different sea states (Langmuir turbulence), which are highly complex and variable in tropical cyclone conditions. In this study, the upper ocean response under Hurricane Edouard (2014) is investigated using a coupled ocean‐wave model with and without an explicit sea state dependent Langmuir turbulence parameterization. The results are compared with in situ observations of sea surface temperature and mixed layer depth from AXBTs, as well as satellite sea surface temperature observations. Overall, the model results of mixed layer deepening and sea surface temperature cooling under and behind the storm are consistent with observations. The model results show that the effects of sea state dependent Langmuir turbulence can be significant, particularly on the mixed layer depth evolution. Although available observations are not sufficient to confirm such effects, some observed trends suggest that the sea state dependent parameterization might be more accurate than the traditional (sea state independent) parameterization.

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