Wednesday, 25 April 2018

New Paper Shows Global Warming May Be Much Slower Than Estimates

paper just published by the American Meteorological Society's Journal of Climate concludes that high estimates of future global warming from most computer climate simulations are inconsistent with observed warming since 1850.

The implication is that future warming will be 30 to 45% lower than suggested by the simulations.

Abstract  and 

Energy budget estimates of equilibrium climate sensitivity (ECS) and transient climate response (TCR) are derived based on the best estimates and uncertainty ranges for forcing provided in the IPCC Fifth Assessment Scientific Report (AR5). Recent revisions to greenhouse gas forcing and post-1990 ozone and aerosol forcing estimates are incorporated and the forcing data extended from 2011 to 2016. Reflecting recent evidence against strong aerosol forcing, its AR5 uncertainty lower bound is increased slightly. Using a 1869–1882 base period and a 2007−2016 final period, which are well-matched for volcanic activity and influence from internal variability, medians are derived for ECS of 1.50 K (5−95%: 1.05−2.45 K) and for TCR of 1.20 K (5−95%: 0.9−1.7 K). These estimates both have much lower upper bounds than those from a predecessor study using AR5 data ending in 2011. Using infilled, globally-complete temperature data gives slightly higher estimates; a median of 1.66 K for ECS (5−95%: 1.15−2.7 K) and 1.33 K for TCR (5−95%:1.0−1.90 K). These ECS estimates reflect climate feedbacks over the historical period, assumed time-invariant. Allowing for possible time-varying climate feedbacks increases the median ECS estimate to 1.76 K (5−95%: 1.2−3.1 K), using infilled temperature data. Possible biases from non-unit forcing efficacy, temperature estimation issues and variability in sea-surface temperature change patterns are examined and found to be minor when using globally-complete temperature data. 

These results imply that high ECS and TCR values derived from a majority of CMIP5 climate models are inconsistent with observed warming during the historical period.

Read more at Climate Change Dispatch.

"Secret Science" departs after "Fake News"

Potus Trump exposed the Main Stream Media's "Fake News" after his election. eg
Now, Environmental Protection Agency Administrator Scott Pruitt today announced the end of “secret science” at the agency. In a press release from the EPA: (link)

WASHINGTON (April 24, 2018) – Today, U.S. Environmental Protection Agency (EPA) Administrator Scott Pruitt signed a proposed rule to strengthen the science used in regulations issued by EPA. The rule will ensure that the regulatory science underlying Agency actions is fully transparent, and that underlying scientific information is publicly available in a manner sufficient for independent validation.
“The era of secret science at EPA is coming to an end,” said EPA Administrator Scott Pruitt. “The ability to test, authenticate, and reproduce scientific findings is vital for the integrity of rulemaking process. Americans deserve to assess the legitimacy of the science underpinning EPA decisions that may impact their lives.”