The Conveyer Belt ...

Surface temperatures in the western North Atlantic. The North American landmass is black and dark blue (cold), while the Gulf Stream is red (warm). Source: NASA

Back in 2015, yours truly discussed the loss of Albedo, whereby the effect of turning the North Pole from a reflective source of sunlight to a heat sink, due to the loss of polar ice, would, in part, slow the Gulf Stream. Seems this dire prediction's coming true which, in turn, will eventually turn Sweden, England and connected environs, into an ice box.

An influential current system in the Atlantic Ocean, which plays a vital role in redistributing heat throughout our planet's climate system, is now moving more slowly than it has in at least 1,600 years. That's the conclusion of a new study published in the journal Nature Geoscience from some of the world's leading experts in this field.

Scientists believe that part of this slowing is directly related to our warming climate, as melting ice alters the balance in northern waters. Its impact may be seen in storms, heat waves and sea-level rise. And it bolsters concerns that if humans are not able to limit warming, the system could eventually reach a tipping point, throwing global climate patterns into disarray.

NOAA

The majority of that heat is redistributed by the atmosphere. But the rest is more slowly moved by the oceans in what is called the Global Ocean Conveyor Belt — a worldwide system of currents connecting the world's oceans, moving in all different directions horizontally and vertically. 

Through years of scientific research it has become clear that the Atlantic portion of the conveyor belt — the AMOC — is the engine that drives its operation. It moves water at 100 times the flow of the Amazon river. 

CLIMATE CENTRAL

The prime driver for the slowing is the density of fresh water and how it acts as a cap over salt water.  To whit ...

One important mechanism through the ages, which acts as a lever of sorts controlling the speed of the AMOC, is the melting of glacial ice and resulting influx of fresh water into the North Atlantic. That's because fresh water is less salty, and therefore less dense, than sea water, and it does not sink as readily. Too much fresh water means the conveyor belt loses the sinking part of its engine and thus loses its momentum.

As proof ...

Almost all of the globe is warming except for a cold blob in the North Atlantic. NASA

Recently scientists have noticed a cold blob, also known as the North Atlantic warming hole, in a patch of the North Atlantic around southern Greenland — one of the only places that's actually cooling on the planet.

The fact that climate models predicted this lends more evidence that it is indicative of excess Greenland ice melting, more rainfall and a consequent slowdown of heat transport northward from the tropics.

The CBS blurb's long but worth reading to learn just how important the Gulf Stream truly is to the earth's climate as man moves further into the 21st century. 

Addendum, check out the involved NYTimes piece on the Gulf Stream. Ominous says it all.