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Education: Water Cycle

86% of global evaporation and 78% of global precipitation occur over the ocean; thus sea surface salinity (SSS) is the key variable for understanding how fresh water input and output affects ocean dynamics.

Earth's "water cycle" is dominated by ocean-atmosphere exchanges: globally, 86% of evaporation and 78% of precipitation occur over the ocean. SSS is a key tracer for understanding the freshwater fluxes into and out of the ocean system. This is because some parts of the water cycle decrease salinity (e.g., precipitation, groundwater flow to the ocean, river runoff) and some parts increase it (e.g., evaporation and freezing of seawater). With Aquarius data, scientists will be able to relate SSS variations to evaporation and precipitation, providing insight into how the ocean responds to seasonal and annual variability in the water cycle.

Search our database for assets related to the water cycle.