Boom! Goes the dynamite.
Crisis looms in alarmist climate science
Climate science is dominated by alarmists addicted to the idea that increasing carbon dioxide will cause dangerous global warming. How much warming is thus the central scientific question.
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". . . For many decades the accepted model estimates of ECS have ranged from 1.5 to 4.5 degrees C. Different models give different values, but the acceptable range has not changed. That the range is so big has been a policy problem. Warming as little as 1.5 degrees might be harmless, while 4.5 might be dangerous. But the ECS range has been stubbornly persistent, refusing to narrow to a specific value.
Now, suddenly, there is a huge new problem. ECS has exploded! It is not that it is higher, or lower — it is both. Two new lines of research have diverged sharply on the estimated value of ECS.
The first line of research takes a new approach called observational ECS. The idea is that since the CO2 level is almost half way to doubling we should be able to derive ECS empirically from the observed relationship between CO2 increase and temperature increase.
There have been a number of observational studies and many are getting ECS values well below 1.5, which are harmless indeed. Values of 1.2 and 1.3 are common.
But at the same time there has been a new wave of modeling studies and these are getting ECS values way above 4.5, which would be truly dangerous. Here values of 5.2 and 5.3 are to be found.
Note that the modeling community is divided over accepting these new hot model numbers. After all, they imply that the modeling done over the last forty years or so has been wrong, including a lot of the recent modeling which is still within the old range.
The upshot of all this is that the science of ECS is in a shambles. Given that ECS addresses the core science of climate alarmism, this is truly a crisis. Has the modeling been wrong for 40 years? Is it wrong now? What about observation, which is supposed to rule in science? The scientific method says observation trumps theoretical modeling. . . . ."