Vital ocean current on verge of collapse

By 2050, melting ice sheets could weaken or even halt an essential Atlantic Ocean current that transports heat, salt and nutrients around the globe, according to a new study, with catastrophic consequences


THERMOHALINE CIRCULATION

Atlantic Meridional Overturning Circulation

1 Warm, less saline water flows north, where it cools to form sea ice

2 Deep water formation: cooler, more saline, denser water, sinks

3 Deep water loses salinity and rises to surface

Takes around 1,000 years for water to complete cycle

Antarctic Circumpolar Current

Deep current
Surface current

Atlantic Ocean
Indian Ocean
ANTARCTICA


Melting Greenland ice sheet lowering salinity, sea ice not forming, overturning slowing

High salinity
Sea level rise
Amazon drought
Drought
Storms, 10 ̊C fall in temperature
Monsoon disruption
Low salinity


Sources: New Scientist, NOAA
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