New Hot Zones now cover 5% of Earth; Only Fix is Halting CO2 (Lazare)

Sarah Lazare writes at

A new study dishes out some very bad news about the global warming crisis.

It is too late to stop a “several folds” increase of deadly heat waves caused by greenhouse gases—and the floods, fires, and storms they bring.

The report comes as a record heat wave hits North Asia, killing dozens and sickening far more, flooding hospitals with heatstroke victims amid power shortages that are cutting off air conditioning in some areas.
Heat wave aerial view

Published Thursday in the Environmental Research Letters, the study tracks trends in heat increases, finding that “3-sigma” heat wave events . . . have been on the rise since the 1950s and today cover approximately 5 percent of the earth’s land surface.

No amount of emissions mitigation can stop this frequency from doubling by the year 2020 and quadrupling by 2040, and by the latter year, extreme heat events will cover 20 percent of the globe. Furthermore, 5-sigma events, which do not occur presently, are expected to ravage 3 percent of the world’s surface by 2040.

Study scientists claim that humanity’s best hope is to stabilize heatwaves in the second half of the 21st century through an aggressive curb on greenhouse gases.

“[An] important message from this study is that a further increase during the second half of the 21st century can be stopped if we reduce CO2 emissions fairly soon,” Dim Coumou, a climate scientist with the Potsdam Institute for Climate Impact Research in Germany and first author of the study, told NBC.

However, if greenhouse emissions are not curbed, deadly climate disaster will spiral further. If carbon levels in the atmosphere are still high after 2040, 3-sigma heat events will be common occurrences in 85 percent of the world, and 5-sigma heat events will occur in 60 percent of the world by 2100.

It is well documented that the deadly effects of global warming are felt most by the global south, yet the global north holds more responsibility. A National Resources Defense Council report predicts that, by the end of the century, 150,000 people in the U.S. could die as a direct result of heat waves alone, with the projected deaths from global warming overall far higher.


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6 Responses

  1. While I do not disagree with Sarah Lazare’s piece, and certainly do not disagree with the weight of evidence that demonstrates AGW – I think this is mistaken:

    “…finding that “3-sigma” heat wave events, in which climates are warmed to 3 times their normal temperature for over 3 weeks in a row”

    Pretty sure “3-sigma” pertains to 3 standard deviations from the mean – so a 3 sigma event would be something that would happen (normally) about 1 in ~300 times.

    Thus, observing clusters of these supposed-to-be-rare events is a good indicator that the distribution of the data (the climate in this case) has shifted.

    link to

  2. Am I missing something? A “3-sigma heat wave event” in which “climates are warmed to 3 times their normal temperature for over 3 weeks in a row” would seem to mean that a 70 degree climate is warmed to 210 degrees? For three weeks. Ehere has it been 210 degrees for three weeks? This year’s heat record was 134 degrees at Death Valley.

    Even if you’re looking at a more temperate locale, where has a 50 degree climate shot up to 150 degrees for three weeks?

    And “5-sigma” events are predicted in which temperatures would climb to 350 degrees? Are we talking about the planet Earth?

    • The chosen wording was very poor. See Eric’s comment above. Of course describing future weather in terms of the current (or the already past) climate and its distribution of weather has is problematic as well. Means and variances will shift as the climate changes. Maybe there just isn’t a way to dumb this stuff down, and not end up with misleading language?

      BTW. the years highest was 129.2 at death valley. The 134 from 1913 is almost certainly in error, and this years value is probably the highest reliably recorded value in the world.

    • A cursory search on “3-sigma event heat waves” makes it clear that what should have been written was “three standard deviations from the historical average.” If one goes on to look at the source material, one sees some degree of confidence in the prediction that 3- and 5-sigma events “will be the likely norm for the 21st century.” link to So let’s not lose the reality in impeachment fog…

      In the meantime, think of the air conditioner sales possibilities! The opportunities for those who can invent “windtraps” to take moisture out of the air! Maybe some smart folks will even develop suits we can wear that will catch and recycle our perspiration and urine and fecal matter! And all that new waterfront property! and the weapons and troops needed to Keep Order!

      Seems we, collectively, have been handed the responsibility for our own futures. Too bad that we’re ruled, as a species and (collective guilt) as most individuals, by people and preferences that feature short-term profit maximization, “demand manufacturing,” the pleasure principle, the way our commercial and consumptive cultures and the ruling institutions have grown make it da_n unlikely that our kids and grandkids will have a lot to work with or much of a chance to fix anything. But the sh_ts who have moved us into this Dead Zone, the Robber Barons and early other Captains of Industry and more recently people like Henry Ford and the Koch Brothers and Murdoch and even the sainted Warren Buffett, will of course be long and comfortably dead after lives mostly characterized by grotesque accumulation, and slick perversion of politics and polities, and self-pleasing. No consequences, no restitution, not even any retribution for those who force most of us to slave and suffer and die in terror and misery…

  3. Every little bit contributes:
    Excerpts: European forests are showing signs of reaching a saturation point as carbon sinks, a study has suggested.

    Since 2005, the amount of atmospheric CO2 absorbed by the continent’s trees has been slowing, researchers reported. Writing in Nature Climate Change, they said this was a result of a declining volume of trees, deforestation and the impact of natural disturbances…..Carbon sinks play a key role in the global carbon cycle and are promoted as a way to offset rising emissions…..Acer autumn leaves (Image: BBC) Many of Europe’s forests are reaching an age where growth, and carbon uptake, slows down….Writing in their paper, the scientists said the continent’s forests had been recovering in recent times after centuries of stock decline and deforestation….The growth had also provided a “persistent carbon sink”, which was projected to continue for decades…..However, the team’s study observed three warnings that the carbon sink provided by Europe’s tree stands was nearing a saturation point….”First, the stem volume increment rate (of individual trees) is increasing and thus the sink is curbing after decades of increase,” they wrote…..”Second, land use is intensifying, thereby leading to deforestation and associated carbon losses…..”Third, natural disturbances (eg wildfires) are increasing and, as a consequence, so are the emissions of CO2.”

    Co-author Gert-Jan Nabuurs from Wageningen University and Research Centre, Netherlands, said: “All of this together means that the increase in the size of the sink is stopping; it is even declining a little….”We see this as the first signs of a saturating sink,” he told BBC News.

    link to

  4. If you click on the link and read the referenced piece, the next to last two paragraphs explain that “sigma” is measuring variability from past norms in a particular region.

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