Scientists in Scotland are using robotic subsea gliders to check ocean currents for signs of climate collapse.
They are monitoring the “conveyor belt” which carries warm and cool water between the Caribbean and the Arctic.
Scientists fear a weakening of the system would have a devastating effect across large parts of the planet.
The Scottish Association for Marine Science (Sams) at Oban is deploying the robots on autonomous missions between the UK and Iceland over five months.
Atlantic circulation is important for distributing tropical heat across the world and keeps northern Europe at a more temperate climate than other locations on the same latitude.
Its collapse is referred to as one of the climate “tipping points” and there is some research to suggest it might be very slowly weakening.
Because it fluctuates, experts say circulation needs to be monitored closely over several decades for any firm conclusions to be made about its strength.
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