How hot will it get later this century? So hot that we'll need new terms.

 A new study paints a grim climate picture for the Middle East and North Africa (MENA). 

As reported in the prestigious, peer-reviewed journal NPJ/Climate and Atmospheric Science, first-of-their-kind regional climate models project prolonged, life-threatening heat waves impacting up to 600 million people in the MENA region if global warming is not brought under control. In a "business-as-usual" scenario, temperatures are projected to soar to 56 degrees Celsius (133 degrees Fahrenheit) and remain at such intolerable levels for days or weeks at a time in the second half of this century. 

We need new terms to categorize such intense, extended and deadly heat events. "Our results for a business-as-usual pathway indicate that especially in the second half of this century unprecedented super- and ultra-extreme heatwaves will emerge," says George Zittis, first author of the new study.

The authors point out that by mid-century, 90 percent of the population of the MENA region are expected to be living in cities. Cities act as "heat islands" that intensify and prolong extreme heat events. That means that a high percentage of the regions projected population of one billion will face such life-threatening conditions almost every year towards the end of the century.

"For the following decades and towards the end of the 21st century, thermal conditions in the region are projected to become particularly harsh as the so-far-unobserved and thus unprecedented "super-extreme" and "ultra-extreme" events are projected to become commonplace," the authors write.

Daily heat wave magnitude averages from 1980s projected through 2100

Credit: Zittis et al./NPJ/Climate and Atmospheric Science

If the world continues on its current business-as-usual path, the Middle East and North Africa will clearly be at risk, not just of increased human mortality, but of disruption of work, agriculture and daily life. Since the most extreme conditions this study foresees have not yet been experienced, how much personal, social, economic and political disruption they will cause remains to be seen. However, like the heat projections, those disruptions are likely to be extreme, super-extreme or ultra-extreme. And, as we know, problems that start in the Middle East do not stay in the Middle East.

If world leaders needed any more motivation to turn the looming climate catastrophe around now, here it is.

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REA/4-29-21

HOW TO DRILL AND BURN OUR WAY BACK TO THE TRIASSIC

I know that not many of us--and certainly not the President or our representatives in Congress--are thinking past the next vote or at most the next election.

Still, for those who care about the next few generations, here's a heads-up from a trio of earth scientists in the U.S. and the U.K., writing in the prestigious journal Nature Communications.

They warn that if we burn all available fossil fuel reserves within the next few hundred years, the combination of high levels of CO2 in the atmosphere and more intense radiation from the sun will turn up the heat to levels not seen on Earth since the Triassic period, 220 million years ago, or perhaps ever.

In case you don't remember the details, the Triassic featured one giant continent called Pangea. The poles were ice-free. It was hot and steamy near the coasts, baking desert inland, and Earth was dominated by the reptilian ancestors of dinosaurs, birds, mammals, and, way in the distance future, us. An interesting place for a quick visit, but not where most of us would want to live.

Postosuchus, a Triassic archosaur

Credit: Dallas Krentzel, Museum of Texas Tech University

Steamy as it was with atmospheric CO2 around 2000 parts per million, it wasn't as hot as it will be by 2250 AD if we've boosted CO2 to that same level. The reason is that the sun is gradually getting hotter. The increase in solar radiation over the course of the past 220 million years means that the combined impact--a dense greenhouse atmosphere and a hotter sun--would push Earth--and anyone still around then--into an unprecedented and unpredictable climate zone.

"Such a scenario," the authors write, "risks subjecting the Earth to a climate forcing that has no apparent geological precedent, for at least the last 420 Myrs [million years]."

So, if the first line of our business-as-usual mantra continues to be "drill, baby, drill," the next line is even more likely to be "burn, baby, burn."

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