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Frequently Asked Questions:

1: What are the 'Gulf Stream' and the 'AMOC'?

The Gulf Stream is a northward-flowing surface ocean current tracking the eastern sea board of the United States before heading east into the North Atlantic, where it becomes known as the 'North Atlantic Drift'.

It is a component of the Atlantic Meridional Overturning Circulation - or AMOC. This is a basin-wide, full depth, circulation system resulting in warm, salty water flowing north and cooler, sub-surface water transported south.

2: Could the Gulf Stream switch off and plunge Europe into an Ice Age?

Present assessments suggest a partial slow-down of the AMOC is very likely this century, but that the risk of a total collapse is low. The cooling effects of a partial slow down are accounted for in major climate projections, such as those available from the IPCC and UKCIP, and are not enough to reverse the effects of global warming.

In the event of a total shutdown the amount of global warming experienced by the UK would be offset by ~2-4 degC, predominantly in winter. Therefore, the amount of warming that had already occured before the shutdown would dictate whether there would be a net increase or decrease in temperature.

Cooling in the Arctic and sub-Arctic in the event of a shutdown would be more severe, reversing even extreme scenarios of warming, resulting in significant changes to sea ice extent and other features of the regional climate.

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