Climate Explainers: Colder Winters – Because Climate Change
Climate explainers are struggling trying to tell us why it is all our fault that bitter cold is gripping the USA this winter, our fault that winters have grown colder in Europe and the USA over the last 25 years.
Why So Cold? Climate Change May Be Part of the Answer
By HENRY FOUNTAINJAN. 3, 2018
As bitter cold continues to grip much of North America and helps spawn the fierce storm along the East Coast, the question arises: What’s the influence of climate change?
The reason a direct connection between cold weather and global warming is still up for debate, scientists say, is that there are many other factors involved. Ocean temperatures in the tropics, soil moisture, snow cover, even the long-term natural variability of large ocean systems all can influence the jet stream.
“I think everyone would agree that potentially the warming Arctic could have impacts on the lower latitudes,” said Rick Thoman, climate services manager with the National Weather Service in Fairbanks, Alaska. “But the exact connection on the climate scale is an area of active research.”
But scientists have been puzzled by data that at first seems counterintuitive: Despite an undeniable overall year-round warming trend, winters in North America and Europe have trended cooler over the past quarter-century.
“We’re trying to understand these dynamic processes that lead to cold winters,” Ms. Kretschmer said
She is the lead author of a study published last fall that looked at four decades of climate data and concluded that the jet stream — usually referred to as the polar vortex this time of year — is weakening more frequently and staying weaker for longer periods of time. That allows cold air to escape the Arctic and move to lower latitudes. But the study focused on Europe and Russia.
“The changes in very persistent weak states actually contributed to cold outbreaks in Eurasia,” Ms. Kretschmer said. “The bigger question is how this is related to climate change.”
Settled science anyone?
My biggest problem with these in my opinion nonsensical explanations is that they require belief that we used to inhabit a perfect magic optimum.
This theory falls apart with any kind of close examination. Pre-industrial winters, especially during the Little Ice Age, were often brutally cold.
The current trend to colder winters could simply be a fluctuation of natural forcings. But if natural forcings can so easily overwhelm the alleged anthropogenic CO2 climate control knob, is the CO2 forcing really that powerful? Questions might be asked about whether the science really is as settled as proponents claim.
So climate explainers try to relate every unexpected temperature excursion back to our sinful industrial emissions.
If winters continue to cool, as they have cooled for the last 25 years, my guess is climate explainers will have to work ever harder to maintain the confidence of their dwindling audience of true believers.
via Watts Up With That? http://ift.tt/1Viafi3