The Point of No Return for the Warm Water Atlantic Current Is Coming Up Fast

A simplified animation showing the overturning circulation. Red lines are surface currents, blue are underwater. NASA/Goddard Space Flight Center Scientific Visualization Studio (source)

By Thomas Neuburger

We will probably pass the tipping point for an AMOC shutdown in the next ten to twenty years or so. —Climate scientist Stefan Rahmstorf Does death make our lives less sweet? For most of us, no. —Yours truly

Time for a climate update. Tipping points are approaching. To present this information systematically, consider the following:

• Bad things are already happening, and they’ll continue. • Over not much time, the bad things will also get worse. • Then tipping points will be reached, after which the worst is baked in. • Some years after that, the worst arrives in full.

This process is true in a great many areas: sea level rise, for example, and coastal destruction.

The seas are already rising, due partly to ocean expansion (warm water takes up more space than cold water), but due mainly to melting ice in Greenland and Antarctica. Once the tipping point for glacial melt has been reached, all ice will be guaranteed gone at some future time, and a full sea level rise disaster is bound to occur.

What will that look like? Greenland ice melt will cause 24 feet of sea level rise; Antarctica ice melt, 230 feet. The world’s coastal cities, where 15% of world population lives, will erode with the shores and be drowned. In the U.S., 45% of GDP will be lost.

The point to remember: this all occurs in stages. First, pain. Then greater pain. Then a tipping point, which may not be marked by an event, but which nonetheless guarantees, at some future time, complete collapse of the system under discussion.

For most of our systems, we’re at the first point now, or possibly the second — a point of considerable pain. Yet tipping points silently lurk, some quite nearby.

The ‘AMOC’, Europe’s Personal Heat Pump

With that, let’s look at one system under threat, the system of oceanic Atlantic currents that keeps northern Europe from freezing like Canada.

Winter in Montreal (source)

Europe’s personal heat pump is the Atlantic Meridional Overturning Circulation, or AMOC — what most of us call the “Gulf Stream,” though those two are not quite the same. The AMOC is part of the world-ocean circulatory system that takes warm water from Equatorial zones and moves it across oceanic surfaces to the north and south, where it cools and sinks, then returns as deep water currents (see image above).

The part Europeans care about is the part that runs from the Gulf of Mexico to very near Scotland. Paris, for example is three degrees latitude closer to the North Pole than Montreal, and Scotland is closer still. Yet northern Europe is warmed by the AMOC, while Canada is not.

Northern Europe is warmed by the AMOC, while Canada is not. The two pins above are cities on the same latitude line. (Image source)

Now consider the video below. In it, notable (very notable) climate physicist Stefan Rahmstorf discusses in scientific terms the future of AMOC. The whole thing is just 15 minutes, but you can start, if you like, at 12:43 to hear his tipping point prediction.

Rahmstorf’s bottom line: “We will probably pass the tipping point for an AMOC shutdown in the next ten to twenty years or so.” In other words, sometime between 2035 (ish) and 2050.

We won’t see it happen, most likely, that tipping point passed. But it will be passed nonetheless.

A Note for Skeptics

I understand that some readers here are climate skeptics. These are, after all, projections, and models can err. (Most of our climate models, in fact, have erred already, but on the side of complacence.)

These doubts don’t trouble me. No one’s optimism will change the future; nor will anyone’s doubt. Things will be what they are — decent or rough — regardless of anyone’s thoughts.

I will say this briefly, though, to the skeptically inclined: Watch your local environment for signs of increasing pain: diminishing water supplies; long and deep droughts; more costly insurance; bigger, more frequent hurricanes, storms and fires; fewer insects (sorry, that’s already here); more frequently canceled sporting events perhaps.

If you see these signs, prepare, regardless of what you believe to be the cause. Protect yourself. And if it turns out you’re right after all, I’ll be among the first to celebrate with you.

A Note for Believers

It’s easy to look at all this and become depressed. After all, this represents a kind of death, if not of ourselves as individuals, of the future the stories we constantly tell ourselves is certain to come — a future that’s somehow continuous with our own.

Consider our films and novels. Most stories that are set ahead some number of years ignore the climate and focus on new technology. Makes for a great film. But the climate — whose kingship is certain so long as we’re ruled by our current pathological lords — will kill off our tech. The wave of smart-phone delights that has given such joy is due to recede, and won’t return, perhaps, for a thousand years.

The way to stay centered is this: We all understand we will die, a personal destruction, yet most live unbowed by that weight — we eat, watch sports, fall in love, mourn losses, cheer gains, hug children, meet friends; in general we still attempt to live happy lives.

Does death make our lives less sweet? For most of us, no. Though death can’t be stopped; we don’t let it drag us down.

Same here. If you think the destruction of our climate and way of life, which the arrogant and greedy are dead-on determined to cause, can’t be stopped, then think of it as you do your personal future loss, and try to live well anyway. That choice is no different than the one you faced yesterday.

And if you think of a way to stop those pathological souls, those less-than-a-thousand folks who have charge of our lives, then do it. There’s joy in that too.