Gulf Stream and Global Warming? How will rising global temperatures (natural or manmade) influence the Gulf Stream, which is responsible for moderating Europes winter climate?

With an increase in cold fresh water input into the Nth Atlantic ocean, surely this will cause the Gulf Stream to fail (as it may already be doing so - with a 30 % reduction in water flows since 1990). As a result, wouldn%26#039;t Europe/Greenland be plunged into an Ice age of sorts, effectively cancelling out the expected effect of global warming?

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1 month ago

davem - granted melting does occur now as it always has, but normally only during the summer months, but with a general warming of the northern regions, unusual freshwater runoff would occur during the winter months as well.

We don%26#039;t know for sure--but that is the scenario that most analysis suggests. So it%26#039;s pretty much the working hypothesis.

With one change--Greenland (except for the southern tip) is not affected by the Gulf Stream. However, the eastern seaboard of North America is. Thee --and in the north-northwest parts of Europe, the British Isles, Iceland, and possibly the Scandanavian region would be affected.

The total global effect of having a lot of cold fresh water over the Arctic and N,Atlantic will mostly depend on whether the Arctic is largely ice free in summer. If it is, the earth continues to absorb sunlight in summer. Otherwise we regain reflectivity and global warming might stall.

What a coincidence, the history channel did a documentary today discussing about this topic.