Study Links Severe Winter Weather in Northeastern U.S. to Arctic Temps

The frequency of extreme winter weather in the U.S. is sensitive to Arctic temperatures, and that’s something those paying weather-related losses may want to take note of.

After all, you can’t spell polar vortex without the “polar.”

The study (Warm Arctic episodes linked with increased frequency of extreme winter weather in the United States) from Atmospheric and Environmental Research – AER is a Verisk business – and Rutgers University published in Nature Communications shows that in the Eastern U.S. severe winter weather is 2 to 4 times more likely when the Arctic is abnormally warm compared with when the region is abnormally cold.

In recent decades, extreme winter weather has become more strongly connected to disruptions in the polar vortex, according to the study, which also shows that winters are colder across much of the Northern Hemisphere mid-latitudes, including Europe and East Asia, when the Arctic is very warm.

“Variability in the day-to-day weather is due to a combination of forced and natural variability,” the study published in Nature Communications states. “Forced variability results from boundary conditions, such as sea-surface temperatures, and natural or internal variability results from the chaotic nature of dynamical systems.”

The tropics have been traditionally considered the main driver of “boundary-forced variability,” but recent studies indicate the Arctic is playing an increasingly important role as a boundary-forcing agent due to its accelerated warming.

“Increasing greenhouse gases are contributing to a general warming of the atmosphere and oceans globally,” the study states. “Over recent decades, warming has dominated global temperature trends during three of the seasons. In winter, however, cooling trends have been observed across Eurasia and the Eastern U.S., along with rapid warming in the Arctic.”

This seesaw winter temperature pattern is known as the warm-Arctic/cold-continents pattern, the study notes

The study points out that during the past three decades, the Arctic has experienced the greatest climate changes of anywhere on the planet, including rapidly rising temperatures, melting sea ice, diminishing spring snow cover and increasing autumn snow cover.

Rapid Arctic warming relative to the rest of the globe is known as “Arctic amplification.” The study looked into whether Arctic amplification is contributing to more frequent severe cold and heavy snowfalls in the Eastern U.S.

“The publication of the paper is especially timely given the extreme winter of 2017/2018, which has included a record-warm Arctic and record-low sea ice, record-breaking polar vortex disruption, record-breaking cold in both the U.S. and Europe, disruptive snowfalls in both the U.S. and Europe, severe ‘bomb cyclones,’ and costly nor’easters,” Judah Cohen, director of seasonal forecasting at AER and lead author of the study, said in a statement.

The paper asserts that the weather was cold not in spite of climate change but likely because of it.

“In fact, our statistical analysis shows that one is more likely to be struck by lightning, attacked by a shark, and win the Powerball all at the same time than the possibility of severe winter weather in the Northeastern U.S. not being related to Arctic temperatures,” Cohen states. “That’s how robust our findings are.”


More than 90,000 people are calling on Generali to end all support of coal right as Europe’s third biggest insurer announced record 2017 financial results on Thursday.

Philippe Donnet, chief executive officer at Generali, told CNBC on Thursday he was happy with the company’s results. The carrier posted a full-year net profit of 2.11 billion euros ($2.6 billion), versus 1.96 billion euros expected in a consensus provided by the company. Operating profit rose 2.3 percent to hit 4.89 billion euros in 2017, versus 4.86 billion euros outlined in an analyst consensus.

A petition on WeMove.EU, organized by non-governmental organizations supporting the Unfriend Coal campaign, was one of three petitions circulated that called upon Generali to stop insuring coal projects and divest from the industry.

“Every day 53 people in Europe die an early death because of coal pollution,” states the WeMove.EU petition.

The petition highlights Generali’s support for Poland’s coal industry, which causes an estimated 5,830 premature deaths every year including 430 in its home country Italy, according to the petition.

Generali provides insurance for Europe’s second largest coal plant, among other plants, in Kozienice, Poland, which even before a recent expansion it was estimated to cause 650 premature deaths each year, 14,140 asthma attacks in children and emit millions of tons of CO2, the petition states.

The WeMove.EU petition accuses Generali of putting profits before people and it calls on the carrier to follow the lead set by AXA, Zurich and SCOR by announcing restrictions on underwriting coal projects and ending investments in the industry.

AXA announced in 2017 its pledge o stop insuring any new coal, tar sands and associated pipeline projects and to divest another €2.4 billion from coal and €700 million from oil sands and producers and associated pipelines. Axa, France’s largest insurer, has been out in front on divestiture for several years. In 2015 the insurer announced its plans to scrap holdings in coal companies because of concerns about climate change.

Generali in February announced plans to divest €2 billion from coal and make no new investments in businesses associated with the coal sector, but Unfriend Coal wants more from the carrier.

The campaign is also calling on insurers to adopt divestment criteria based on a Global Coal Exit List, and asking insurers to divest their own assets and assets managed on behalf of third parties from all companies that: plan investments in new coal power plants, mines and associated infrastructure; generate more than 30 percent of power from coal or have more than 10 GW of installed coal power capacity; derive more than 30 percent of their turnover from coal or produce more than 20 million tonnes of coal a year.

Climate and insurance

Scientists working out of Climate Service Center Germany say efforts are needed to prevent climate change-related events from triggering sudden withdrawals or steep price hikes within the insurance industry.

Rising climate-related risks from floods and windstorms threaten affordability and coverage availability for society at large, and while the solvency of the insurance industry doesn’t seem to be threatened by climate change, “extreme hydro-meteorological events might compromise the ability of insurance companies to deal with climate impacts,” according to story on the website ClimateChangePost detailing the findings.

This could result in companies exiting the market or certain segments becoming uninsurable, the story states.

The story notes that insurers tend to reassess their risks when payouts were higher than estimated, which could result in drops in the affordability and availability of insurance.

“For example, after the 2002 German floods, which cost €9 billion in public funds, some observers noticed that the risk reassessment by insurance companies led to an increase in premiums of up to 50 percent, and a reduction in areas where flood insurance was offered of 10–20 percent,” the story states. “In the U.S., insured losses of over $100 billion caused by Hurricane Katrina and others during 2004 and 2005 resulted in a decrease in the availability of insurance.”

The scientists say continuous efforts are needed to address underlying risks, monitor trends, and come up with solutions to prevent extreme hydro-meteorological events triggering sudden withdrawals or steep price hikes.

“This needs to include broader measures, often not under direct control of the insurance industry, such as adjustments to building standards, stringent land-use planning, and policyholders investing in risk mitigation measures,” the story states. “This is a continuous process that requires monitoring, learning, and innovating. This comes at a cost to the insurance industry, but it is a necessary investment to secure future markets.”


Gizmodo is offering a positive take on climate change – depending on how you look at it – and what may be one of the best headlines on the subject in recent memory: “Climate Change Forced Early Humans to Get Their Shit Together and Innovate.”

“Our species made its debut some 300,000 years ago,” a story out on Thursday states. “During the preceding millenniums, our continent of origin underwent environmental shifts that very likely influenced the trajectory of human evolution.”

The story highlights findings by archaeologists in separate studies working in Kenya showing extent to which climate change influenced the behavior of early humans.

Animals that lived on the changing African landscape hundreds of thousands of years ago were forced to adapt, which in turn forced early humans to spread out, establish trade routes and find innovative ways to build new tools to survive.

“Ancient climate change, according to this view, changed both our biology and our behavior,” the story states. “What’s more, these cultural shifts happened tens of thousands of years earlier than what was suggested by earlier archaeological discoveries.”

Around 360,000 years ago, one region being studied began a transformation from a floodplain to one that fluctuated between wet and very dry conditions. It eventually became grassland, which set the stage for the Middle Stone Age and the emergence of our species, according to the story.

The shift impacted the flora and fauna, including the extinction of number of elephant and horse species only to be replaced by smaller animals like the springbok antelope. That in turn affected humans.

“For early humans, this represented an inconvenient truth: access to food was becoming highly unpredictable,” the story states. “To adapt, the hunter-gathering clans had to disperse and spread out, gather information, and, in the words of the researchers, make an ‘investment in social resource exchange networks’— in other words, they had to start trading goods with other clans.”

These adjustments promoted foraging efficiency, reduced risk and improved the overall fitness of the species, according to the story.

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