If ‘slowdowns’ in global average temperatures can be natural, why not ‘speed-ups’ as well? Recent global temperature patterns correlate very poorly, if at all, with changes in the trace gas CO2 as required by IPCC-supporting climate theorists.

A team of researchers from the U.K., Sweden and Australia has found that three periods of global warming slowdown since 1891 were likely due to natural causes rather than disruptions to the factors causing global warming, reports Phys.org.

In their paper published on the open access site Science Advances, the group describes their study of global mean surface temperatures (GST) since the late 19th century and what they found.

In this new effort, the researchers looked at GST as registered by multiple sources around the globe over the past 127 years, noting the slow march of temperature increases. More specifically, they noted the three previously identified slowdowns in GST increases—the time periods from 1896 to 1910, from 1941 to 1975, and then from 1998 to 2013. They then looked at factors that could have contributed to these slowdowns and found natural causes for each.

The team first reports that their study showed results similar to others regarding GST increases—they have been slowly increasing overall for more than a century. They then offer possible explanations for the three main observed slowdowns in GST increase.

For the first slowdown, they found evidence of El Niño and La Niña weather patterns that likely reduced heating by producing more cloud cover.

For the second slowdown, they found evidence of increased volcanism—smoke and ashes from volcanoes can block sunlight.

The team asserts that the third slowdown, which is also the one on which many global warming skeptics rely, was likely caused by a combination of La Niña events and volcanism. They further note that the third slowdown was not a stopping point—temperatures continued to rise, they just did so at a slower pace.

The researchers also looked at data from studies of the sun and found that there was a slowdown in energy output from 2001 to 2010, which was also a likely contributor to the third slowdown.

Source: Study suggests three periods of global warming slowdown since 1891 due to natural temporary causes | Phys.org