Globally tracing freshwater sources allowed us to quantify the role of SIM and MW in water mass transformation. An interhemispheric asymmetry exists between MW and SIM, steming from the evaporation preconditioning surface waters through the length of the Atlantic which inhibits sea ice formation.

In the Arctic, the story is similar but different, increasing sea ice melt (SIM) is making the Arctic halocline fresher. But now clear significant trends can be found in the densest water masses.

Looking at changes in Temperature-Salinity space allows us to quantify these changes in water masses.

Antarctic Bottom Water (AABW) has freshened during 1980-2023, not because increasing melt from ice sheets, but because of less sea ice being formed - positive trend in sea ice meltwater (SIM).

A Self Organizing Map machine learning technique is used to track the different relationships of salinity and stable oxygen isotopes in different water masses, which then allows us to quantify Sea Ice Meltwater and Meteoric Water (a.k.a. precipitation) in the global ocean.

They now exist.

Marine biogeochemistry
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Polar ocean
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Physical oceanography
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Sea level and coastal erosion
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The “networking” #OSM24