Where will the disasters end?

It's been Armageddon in the Northern Hemisphere: uncontrolled fires around the Arctic Circle (not to mention California and Greece), unprecedented heat waves with temperatures unprecedented, torrential downpours and biblical floods. And yes, it's climate change.

It is quite appropriate to be afraid, because summers will be much worse in 10 years and even worse 10 years later. Rapid and drastic cuts in greenhouse gas emissions could now prevent the summers of the 1920s from worsening, but they would do little to mitigate the growing misery of the next 20 years. These emissions are already in the atmosphere for the most part.

In addition, we will not see "fast and drastic cuts in greenhouse gas emissions" anytime soon. It will get a lot worse before it improves – if it's better. So it is probably time to ask the obvious question: where will all this end?

Gwynne Dyer is an independent journalist whose articles are published in 45 countries.

The worst is not the only case, or even the most likely case, but there may be some value in understanding what this might be if we miss all the outings on the planet. highway in hell. And I will quote here an interview that I made 10 years ago with Dr. Dennis Bushnell, Chief Scientist at the NASA Langley Research Center. Everything is still true today.

He was talking about "feedback" (melting permafrost, warming oceans, huge releases of methane and carbon dioxide). Because they can not yet be fully incorporated into climate models, they lead to systematic underestimates of future warming. And then he went hunting.

"If you take into account all these returns, the estimates are that around 2100, instead of two to six degrees Celsius [in average global temperature] it looks like a possibility of six to twelve degrees ….

" These changes Temperature changes would alter ocean circulation patterns and would end in much of the ocean becoming anoxic – a very low oxygen content – which would then favor bacteria that produce hydrogen sulfates. These would raise and leave the ozone layer, and also make breathing difficult. It's about 2100. "

What Dr. Bushnell was referring to was" Canfield's oceans ", now strongly suspected to be behind four of the five major mbad extinctions Everyone knows the huge asteroid that hit the Gulf of Mexico 65 million years ago and the dinosaurs were wiped out, but there are few people who know that it's n & rsquo; There is no trace of asteroid badociated with the other four "great dies", 444 million, 360 million, 251 million and 200 million years.

A common factor was that the planet was unusually hot at that time, but the real clue was that the deep oceans were anoxic, there was no oxygen there and therefore no life that used oxygen., the "rollover circulation" (like the Gulf Stream) that transports vast amounts of oxygen-rich surface water into the p depths simply stop, and the oceans are stratified into an oxygenated superficial layer and a deeper anoxic layer

still life there: su Bacteria that normally hide in the silt, far from the sea. oxygen that destroys them. In an anoxic ocean, they come out and multiply – and finally, if the conditions are good, they go back to the surface and kill all life with oxygen in the sea.

Not only that, but hydrogen Gaseous sulphide, a waste of their metabolism, rises in the atmosphere, destroys the ozone layer and drifts to the earth where it also destroys the largest part of life. It did not occur once, but at least four times in the past

In theory, by warming the planet, we would create the conditions for a new evolution, but in practice this is not the case. is not very likely. There has been no "Canfield" event in the last 200 million years, and when these mbadive extinctions occurred, the planet was much warmer to begin with.

Even if we avoid this fate, we may be moving towards

Food is the key question: as warming reduces productivity and turns entire regions into desert, mbad starvation is imaginable, although the actual extinction seems improbable.

It is also possible that we will react quickly enough to stop well before mbad death. As for the future, you can only deal with probabilities, and even these are very slippery.

The situation is already rather dark. Bad news, of course, but when you find yourself in a high-stakes game, you need to know what the issues are.