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More specifically, the report’s June draft shows “similar” temperature rises to the earlier reports, at about 1.0-3.7oCelsius by the end of the century. For sea-level rise, the IPCC now includes modeling of glacier responses of 3-20 centimeters, leading to a higher total estimate of 40-62 cm by century’s end – much lower than the exaggerated and scary figure of 1-2 meters of sea-level rise that many environmental activists, and even some media outlets, bandy about.

Similarly, the IPCC has allowed for lower temperature rises by reducing the lower end of its estimate of so-called climate sensitivity. It is also less certain now that humans have caused hurricane and drought events since 1950. In the 2007 report, it was more than 50% certain that they have; now it is less than 21% certain.

Yet these sensible and moderate findings will be met with a predictable wall of alarmism. Many will mimic the blogger Joe Romm, who has declared that “this ultra-conservative and instantly obsolete report ignores the latest science,” and continues to claim 5º C temperature rises and six-foot (1.83 meters) sea-level rises. Romm and many others made similar arguments following the release of the 2007 IPCC report, claiming that the latest, much more alarming, research had been left out.

The bigger problem for the IPCC is that global temperature has risen little or not at all in the last 10-20 years. To be clear, this slowdown does not mean that there is no global warming – there is; but it does call into question how much.

To its credit, the IPCC admits that “models do not generally reproduce the observed reduction in the surface warming trend over the last 10–15 years.” This matters, because if the models overshoot for recent decades, the century-long forecasts are open to doubt.

Compared to the actual temperature rise since 1980, the average of 32 top climate models (the so-called CMIP5) overestimates it by 71-159% (see graph). A new Nature Climate Change study shows that the prevailing climate models produced estimates that overshot the temperature rise over the last 15 years by more than 300%.