https://www.popsci.com/are-we-doomed-arctic-winters-america on November 14, 2014 and
https://www.popsci.com/polar-freeze on July 10, 2017.
Are We Doomed To Arctic Winters In America?
Scientists Square Off On The Coming Freeze
Frigid Friday
Let's all move to Miami.
National Oceanic And Atmospheric Administration
There's an unwelcome guest on your doorstep, America.
It comes from the north, dragging frigid air and awful commutes like a terrible shroud over the continental United States, from the Rocky Mountains all the way to the Atlantic. While the East Coast saw temperatures about 10 degrees below average Friday, snow hit much of the Midwest following a 40 degree drop over just a couple days in Chicago, and a region stretching from Denver to Montana saw sub-zero chills and record lows.
This morning, in the stairwell of an apartment building, even New York City's relatively mild mid-30s weather prodded a father into a shouting match with his weeping child: "But I don't want to go to school today! It's too cold to go outside!" "Put your coat on, now!" And in the halls of climate research centers and weather stations across the nation, the cold snap is spurring a more technical, but no less divisive debate — one that matters to millions of Americans who remember the last awful winter: Is this the new normal?
Ice, Alaska, And Damned Typhoons
Pacific BlastTyphoon Nuri joins the most powerful storms on record in the Bering Strait.
National Oceanic And Atmospheric Administration
With nearly two weeks left before Thanksgiving, this should be a time for tweed and brisk walks through colorful fallen leaves (the autumn the Lands End catalog promised us). Instead, if you live anywhere from Chicago to Appalachia you've likely found yourself breaking out the Gore-Tex for a slog through accumulating snow and ice, with more likely coming this weekend, and its all because of a storm on the other side of the world.
Typhoon Nuri formed in the West Pacific and surged north, peaking with sustained winds around 180 miles per hour — one of the strongest typhoons or hurricanes of the year. As it moved past Japan and into the Arctic it weakened, but its powerful remnants still delivered tropical storm conditions to Alaska's Aleutian Islands, Eastern Russia, and the Bering Strait.
You'd think a mega storm careening off into the underpopulated Arctic would be a kind of best-case scenario, and in many ways it is. There are fewer houses and people out in those cold places, and local damage was minimal. But those sparse communities share air with the jet stream (or "polar vortex"), a muscular current of air that circles counter-clockwise high in the atmosphere between the warmer air masses of the mid-latitudes and the much colder northern reaches.
Several scientists who disagree on most other issues surrounding polar vortex events (including whether "polar vortex" is an acceptable or ridiculous name for these Arctic air surges) came up with just about identical analogies for what happened when Nuri slammed into the jet stream: a taut rope snapping. All that frozen air normally locked in a tight spiral snapped south between an air pressure ridge over the Rockies and Greenland. The resulting arctic wave sunk temperatures far below average along the American continent, and they'll likely remain low for a couple of weeks.
Polar America
Martin Hoerling, a scientist (and according to some of his colleagues, a contrarian) studying climate change with the National Oceanic and Atmospheric Administration (NOAA), says fears of frozen winters future are fair but unfounded.He says, "If I were a member of the public I'd be thinking, 'Oh God, I barely survived the last winter and now it's getting cold again? Is this what I can expect from now on?'" But Hoerling says this pattern of typhoon-induced cold fronts is not new, it's just been given the new, scary, "polar vortex" branding.
If anything, he says, the warming world will see fewer extreme weather shifts because the Arctic and mid-latitudes will be nearer in temperature.
"If I were a member of the public I'd be thinking, 'Oh God, I barely survived the last winter and now it's getting cold again? Is this what I can expect from now on?'"But Jennifer Francis, a researcher with the Institute of Marine and Coastal Sciences at Rutgers University who studies the impact of Arctic warming on the global climate, disagrees. Her research predicts that as Arctic warms (and it is warming extraordinarily quickly) the jet stream will weaken and narrow. "When you have a strong jet stream it's like a thick rope. You can give one end a tug and not much happens." But as it weakens, she says, it's more like a string. A shake (or a typhoon) will send waves all along its length, causing the Arctic monster to move south more often.
While Hoerling dismisses Francis's research as "pure conjecture", and points to early failures to verify her predictions, other meteorologists and climatologists look at "Weakening of the stratospheric polar vortex by Arctic sea-ice loss" and recent studies and are more convinced.
James Overland, also of NOAA, says he leans toward Francis's view. "In the last five years we've seen more of the wavy [jet stream] patterns in January and December than we did before," he says. In his view, it makes sense that a warmed Arctic would break down the jet stream's regular tight ellipse.
Francis acknowledges that her research does not fully account for everything that will impact this winter and those that follow. "All these are pieces to the puzzle," she says.
The debate might seem academic, but its consequences go far beyond discomfort. Last year's harsh winter cost the economy billions, and revealed just how unprepared much of the country is for even slight shifts in storm patterns. More winters like the last could mean more deaths, widespread damage, and economic sluggishness.
So, About January
All other things being equal, meteorologists expect a weak but warming El Niño effect to render this winter a relatively mild one, though forecasters have lowered the probability from 65 to 58 percent at last measure.Hoerling, along with most other researchers, says there's no reason to expect the current cold snap to portend a trend this season. But Francis isn't so sure.
Last year's harsh winter cost the economy billions, and revealed just how unprepared much of the country is for even slight shifts in storm patterns."It all depends on what happens with El Niño — if it does form, what we're seeing right now will probably end," she says. But she says it looks more and more likely that won't happen. "The pattern of surface temperature in the North Pacific look a lot like last winter."
In other words, let's hope that unwelcome guest packs up and leaves for good. But if it comes back, bringing with it plunging mercury, snot-icicles, and general misery, you'd best be ready. Shiver
As the Arctic gets warmer, our winters get colder
And our plants take a hit.
As the arctic warms, it alters weather patterns leading to more frigid winters in North America.
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| U.S.-Canada Fourth Joint Mission To Map the Continental Shelf in the Arctic Ocean |
US Department of State
In the winter of 2015, New York City’s Hudson River froze—a rare occurrence. Prior to the 2000s, the record shows that the Hudson froze in 1720, 1780, and 1821—a period that overlaps with the so-called Little Ice Age, when the Northern Hemisphere was cooler overall. But since the turn of the century, the lower Hudson has frozen not once, but twice: in 2015 and 2003. Meanwhile in the Midwest, the National Oceanic and Atmospheric Administration (NOAA) recorded the winter of 2013-2014 as one of the region’s coldest on record. That is the year, according to Google Trends, that the terms “Polar freeze” and “Arctic freeze” entered the public lexicon.
We didn’t use those terms before because, as a new study released today in the journal Nature Geoscience highlights, we didn’t need them. More intense winters (and their increased frequency) are a new phenomenon courtesy of a warming Arctic.
If the idea that both very cold and very warm winters can be linked to climate change doesn’t sound intuitive, that’s because it isn’t. To figure this out, researchers from Pohang University of Science and Technology in South Korea and from the South University of Science and Technology of China analyzed a number of datasets, beginning with those related to something called teleconnection patterns.
It wasn't until 2013 that we started to talk about Polar Freezes.
Google Trends
Climate anomalies don't happen in a vacuum, but are in fact related to each other even at great distances. The atmosphere acts like a giant, swirling pinball machine—changes in one place can trigger changes in another. We call those weather relationships teleconnections.
The El Niño-Southern Oscillation is perhaps the most famous teleconnection, and though we in the United States tend to experience El Niño directly as warmer weather, the weather effects are caused by changes in the atmosphere. In the case of El Niño, the atmospheric action is what’s known as the Southern Oscillation, a periodic change in atmospheric pressure across the Indonesia Tropical Pacific. This change in pressure triggers what we think of as El Niño type weather.
In studying teleconnections, the researchers recognized that as the Arctic (including Alaska and East Siberia) gets warmer, North America gets cooler in winter—a temperature change strongly correlated to shifts in atmospheric patterns. That shift in conditions, the authors found, also leads to less precipitation in the South-Central portion of the United States.
“The link found between Arctic warming and continental cooling is probably not a simple cause–effect mechanism,” writes Ana Bastos, a researcher at the Laboratoire des Science du Climat et de l’Environement, in an op-ed published alongside the study. She goes on to note that the effect is likely to vary between different regions, and that a closer look could make the relationship between these climate shifts more clear.
In addition to looking at how changes in the Arctic shift weather, the researchers also looked to see what those changes were doing to plant growth. And the consequences for agriculture don't look great. Cold winters and springs lead to biological stress, causing problems in plants that linger even as the temperature warms.
Impacts of Arctic warming on United States crop yields. Light brown and green indicate non-significant states and white means undefined states due to the lack of crop-yield data.
Nature Geoscience
This isn’t just bad for farmers, it’s bad for anyone who wants to mitigate the effects of climate change, which is itself driving much of the Arctic warming. We depend on plants to absorb carbon emissions—they're what's called a carbon sink. So if climate change warms the Arctic, and that triggers weather changes that cool down North American winters and dry out our farms, the resulting agricultural problems could actually make the Arctic warm even more quickly.
This study isn’t the first to find that shifts in teleconnections are leading to odd weather elsewhere. The 2010 heatwaves that hit Russia, for example, and which were found to be caused by climate change, were also linked to severe flooding in parts of India rarely subjected to rain. The message is clear: By messing with the climate, we’re fundamentally changing the weather systems we’ve come to depend upon for human survival.
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