This week's wild weather is a glimpse of what's to come if we don't get our carbon omissions under control.

Famine, already stalking humans across the globe, could soon appear right here at home and in Europe, and this week's wild weather is a small taste of how it would play out.

It all tracks back to our fossil fuel addiction, which has been warming our atmosphere since the 1860s, and is now messing with atmospheric and oceanic rivers of warm and cold water and air.

This week North America experienced the results of a "bomb cyclone," a phenomenon that happens when Arctic air spills out of the Arctic and drools down over North America. Normally that air is kept bottled up in the Arctic by a rigid, fast-moving river of air that circles the north pole called the Jet Stream.

If you've ever watched an approaching thunderstorm on an otherwise clear day, you know what happens when two masses of air with very different temperatures collide: we refer to these as "fronts," and they can stretch for hundreds of miles and carry enormous power.

UN Intergovernmental Panel on Climate Change

How The Artic Freezing Weather is Escaping

The upper-atmosphere Jet Stream, that circular river of Air that rotates around the northern polar region is much like a perpetual front, created by the difference in temperature between the frozen north pole region and the warmer regions a few hundred miles to the south.

The "front" of the Jet Stream thus acts like a "wall around a fortress" that keeps all that Arctic cold air stable and holds it over the north polar region.

Just like the intensity of a thunderstorm front is determined by the difference in temperature between the warmer air in front of it and the cold air behind it, the strength of the Jet Stream is the result of how cold the Arctic is, versus how warm is the rest of the Northern Hemisphere.

Global warming, however, has sped up the warming of the Arctic region between two and six times faster than the rest of the Northern Hemisphere. Polar ice has radically melted in the past 4 decades, replacing white sunlight/heat-reflecting with open blue/black water which absorbs heat instead.

This reduced the difference in temperature between the polar regions and the rest of the Northern Hemisphere so much that the Jet Stream itself has weakened.

As the atmospheric Jet Stream weakens, it can't continue to block freezing polar air exclusively over the Arctic; that Jet Stream river of air then begins to loop and drool down over North America, and the freezing Arctic air behind it spills down over us. The result is the current weather situation across the United States.

While there's some scientific debate about the exact details of how this all works, there's broad consensus that the melting of the Arctic's ice cover, something that has been rapidly accelerating since the 1980s, is principally to blame. And that's driven by fossil-fuel-burning-induced global warming.

In other words, it's getting insanely cold here in North America right now because the Arctic has warmed up so much. If this pattern continues to grow in frequency and severity, it will even further disrupt food production in North America; if it gets sufficiently severe, we could see major food shortages.

Ice is melting, polar bears are losing their habitat, Inuit and Siberian villages are sinking into gooey, melting permafrost, and the paradoxical result is that Dallas is now frozen in and shut down.

While this represents a crisis for Americans, a similar and related but different consequence of global warming deep in our oceans could spell disaster for the Northeastern US and Europeans, as the stable climate that ensures their food supply is similarly at risk.

The Great Conveyor Belt is Breaking Down and Wreaking Havoc

Global warming is messing with the temperature differentials in the extreme north to disrupt the atmospheric Jet Stream.

But there's a similar crisis happening with ocean temperature differentials. These maintain an oceanic flow of warm water from around the southern tip of Africa, up the East Coast of South and North America, and across the Atlantic, where they release heat acquired in the South Pacific and the equatorial region into an area between Iceland and northern Spain.

Scientists call this the Atlantic Meridional Overturning Circulation, or AMOC, but it's popularly known as the Gulf Stream. It's also called The Great Conveyor Belt, as it conveys heat from southern climes to the east coast of North America and Western Europe.

That heat released by the ocean current then blows over Europe, guaranteeing their ability to feed themselves.

This current, known as the Gulf Stream, brings heat to northern Europe, allowing an area at a latitude similar to Alaska — most of central and northern Europe — to enjoy a climate more like Ohio.

If the oceanic Gulf Stream were to weaken or fail, Europe would be plunged into a winter that might not go away. This, in fact, is believed to be one of the primary mechanisms behind the last Ice Age. It was the plot device for the disaster movie The Day After Tomorrow, and has had European scientists increasingly worried for the last few decades.

The Burning of Fossil Fuels is the Culprit

Last month saw the largest temperature anomalies ever measured in the Atlantic and Pacific, directly affecting the oceanic Gulf Stream, that, if they become long-term trends, could threaten the food security of hundreds of millions of Europeans as well as wreaking havoc with weather up and down the east coast of North America.

There's a detailed look at the science from a European perspective, complete with diagrams and maps, here. The impact on North America is laid out in detail here.

All of this is the result of our burning fossil fuels for the past 150 years.

Americans now realize how global warming has made hurricanes and thunderstorms more violent, set parts of the West Coast on fire, created droughts and floods across the central United States in ways never before seen with this ferocity and regularity, and is raising sea levels and endangering our coastal cities.

But as the Jet Stream to our north, and the Gulf Stream to our east continue to wobble and weaken, weather patterns that enable us to predictably grow food and maintain a habitable lifestyle are collapsing.

This severe winter weather is a warning.

If we don't get our carbon omissions under control, and quickly, severe weather disruptions that are initially inconvenient will become civilization-threatening, and eventually could bring down the human species overall.

The crisis is now.

-Thom

Originally posted on thomhartmann.medium.com.