Major 30% reduction in modelers estimates of Climate Sensitivity (Skeptics were right)
Effectively the power of CO2 to warm just got 30% less, according to a team of researchers, many of whom have in the past have published more alarming papers. Remember “there is no debate” and “global warming is a fact” a lot “like gravity”.
Finally the modelers are catching up with the slow-down or pause in global warming over the last decade. Where the best estimate for the IPCC was 3.3 degrees C with a range of 2.0 to 4.5C, Otto et al have revised the best estimate to 2C, with a range of 1.2C – 3.9C.
How the IPCC buried evidence showing good news about global warming
For over thirty years climate scientists have presented a range for climate sensitivity (ECS) that has hardly changed. It was 1.5-4.5°C in 1979 and this range is still the same today in AR5. The new report suggests that the inclusion of recent evidence, reflected in AR5, justifies a lower observationally-based temperature range of 1.25–3.0°C, with a best estimate of 1.75°C, for a doubling of CO2. By contrast, the climate models used for projections in AR5 indicate a range of 2-4.5°C, with an average of 3.2°C.
This is one of the key findings of the new report Oversensitive: how the IPCC hid the good news on global warming, written by independent UK climate scientist Nic Lewis and Dutch science writer Marcel Crok. Lewis and Crok were both expert reviewers of the IPCC report, and Lewis was an author of two relevant papers cited in it.
In recent years it has become possible to make good empirical estimates of climate sensitivity from observational data such as temperature and ocean heat records. These estimates, published in leading scientific journals, point to climate sensitivity per doubling of CO2 most likely being under 2°C for long-term warming, with a best estimate of only 1.3-1.4°C for warming over a seventy year period.
http://www.thegwpf.o...obal-warming-2/
