Yves here. This post gives a tidy and nicely explained example that challenges an oft-made conservative claim: that wilder weather is just weather and has nothing to do with climate change.
However, having lived in the Northeast in the later 1970s and all of the 1980s, it seemed like we got more snow then than when I lived in NYC after 2000. But that may be because the snow stayed around all winter, and kept getting deeper (and dirtier). But with the new normal of higher temps, it would melt away, usually entirely, between storms.
By Michael A. Rawlins, Associate Director, Climate System Research Center, UMass Amherst. Originally published at The Conversation
Bostonians may have grumbled about digging out from almost 2 feet of snow after a historic snowstorm clobbered the Northeast in late January 2022, but it shouldn’t have been a surprise. This part of the U.S. has been seeing a lot of storms like this in recent decades.
In fact, over a century of reliable weather records show many of the Northeast’s heaviest snowfalls have occurred since 1990 – including seven of the top 10 in both Boston and New York.
At the same time, winters in the Mid-Atlantic and Northeast have warmed by approximately 4 degrees Fahrenheit (2.2 C) since the late 1800s.
How can the spate of big snowstorms be reconciled with our warming climate? I’m an atmospheric scientist. Let’s look at an important law of physics and some theories that can help explain the changes.
Warmer Air, More Moisture
First, warmer air can hold more moisture than cold air.
Think of the atmosphere like a sponge. Air holds about 4% more water vapor for each additional degree Fahrenheit increase in temperature (that’s about 7% per degree Celsius). The physical law that explains this relationship is known as the Clausius-Clapyron relation.
This increased atmospheric moisture is helping to intensify the water cycle. The Northeast and Mid-Atlantic have become wetter – not just in winter, but in spring, summer and fall, too. In addition to more total precipitation over a season and year, the additional moisture also fuels extreme events, like more intense hurricanes and flooding rains. The Northeast has seen an increase of more than 50% in the heaviest precipitation events in recent decades, the largest increase of any region of the U.S.
In the early 1900s, winters across the Northeast typically averaged around 22 degrees Fahrenheit. Now, 26 degrees is the official new “normal” temperature, defined as the average over 1991-2020. A few recent winters have been over 30.
In the Northeast, then, we have an environment that has warmed, yet is often still below freezing. Put another way, regions of the world that are cold enough for snow have warmed enough to now be visited by storms capable of holding and dropping more moisture. Rather than intense downpours like Louisiana has been seeing lately, the region gets heavy snow.
The Warming Ocean Plays a Role
The January blizzard was fueled by ocean waters in the western Atlantic that are warmer than normal. That’s also part of a consistent pattern.
The oceans have been absorbing more than 90% of the additional heat attributable to rising atmospheric greenhouse gases from human activities, particularly burning fossil fuels. The oceans now contain more heat energy than any time since measurements began six decades ago.
Scientists are studying whether global warming may be driving a slowing of the ocean conveyor belt of currents that transport water around the globe. Satellite imagery and ocean measurements show that warmer waters have “piled up” along the East Coast, a possible indication of a slowing of the Atlantic Meridional Overturning Circulation.
Moisture evaporated from ocean water provides much of the energy for both tropical and mid-latitude extra-tropical cyclones, known commonly as nor’easters.
The Arctic Influences the Snow Pattern, Too
While tropical storm systems are fueled primarily by warm water, nor’easters gain energy from sharp temperature gradientswhere cold and warm air masses meet. The frequency of cold air outbreaks is another aspect of climate change that may be contributing to recent increases in extreme snowfall events.
Recent research has suggested that a warming Arctic, including declines in Arctic sea ice and snow cover, is influencing behavior of the polar vortex, a band of strong westerly winds that forms in the stratosphere between about 10 and 30 miles above the Arctic every winter. The winds enclose a large pool of extremely cold air.
When the Arctic is relatively warm, the polar vortex tends to be weaker and more easily elongates or “stretches,” allowing extremely cold air to dip south. Episodes of polar-vortex stretching have markedly increased in the past few decades, leading, at times, to more severe winter weather in some places.
What is the polar vortex? NASA explains.
Arctic amplification, the enhanced warming to our north, may, paradoxically, be helping to shuttle cold air to the Eastern Seaboard during polar vortex disruptions, where the cold air can interact with warmer, moisture-laden air from the warmer-than-normal western Atlantic Ocean. The most recent stretched polar vortex event helped to bring together key ingredients for the historic blizzard.
What’s Ahead?
Global climate models project an increase in the most extreme snowfall events across large areas of the Northern Hemisphere with future warming. In some other parts of the world, like Western Europe, intensification of the hydrological cycle will mean more winter rain than snow as temperatures rise.
For the east coast of North America, as well as Northern Asia, winter temperatures are expected to still be cold enough for storms to bring heavy snow – at least through mid-century. Climate models suggest that extreme snowfalls will become rarer, but not necessarily less intense, in the second half of the century, as more storms produce rain.
The sharp increase in high-impact Northeast winter storms is an expected manifestation of a warming climate. It’s another risk the U.S. will have to prepare for as extreme events become more common with climate change.
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One unintended result of a warm/cold and snow cycle is that it will cause havoc for road maintenance. I recall once a visiting Canadian engineer asking why it was in Ireland that we have to replace upland road surfaces so much more than in Canada where the freeze is far more severe. Turns out the answer is that Irelands relatively mild climate means that on uplands in winter roads are subject to repeated cycles of freezing, defrosting, with lots of rain in between. This is far harder for a metalled road to endure than getting covered in snow in fall and then defrosting in spring. The snow acts as a pretty good insulator for the road surface.
I doubt it’s the only variable. By most comparisons roads in California are some of the worst.
Same for cars. GM did a study on this and they found that cars rust the fastest in milder conditions, where temperatures are low enough that salt is applied but high enough that the mush stays mostly liquid. Their engineers advised to park outside in the winter, because that way the snow/salt mix sticking to the underbody would stay frozen and would not be able to rust your car. Parking in the garage would melt the snow and leave the vehicle marinating in salt brine.
Yeps! Spent my formative years in Northern Ontario. Large contingent of folks never washed their cars in winter – it just wet the salt and got it working its rusting magic. Now with the weird freeze/thaw cycle that happens all winter, it is even worse. Wet snow and slush freeze into frozen ruts in sudden temperature drops. Anybody who thinks the weather hasn’t changed significantly in the last few decades is crazy. Temperatures swing and fluctuate in summer (unbearably hot then mild even cool) and winter (so mild we see insects then absolutely bone chilling cold) in mere days. It did not happen when I was a kid. I no longer live in the north but even here where we are, close to Lake Ontario, we pay close attention to the forecast because we want to get wet snow cleaned up before it freezes solid. We had freezing rain on Christmas Day then down to -30C a day or two later. I have been wearing my Icetrax on my boots ever since. The temperature rose 20C in about 12 hours the other day! Now we’re heading back to the deep freeze. And no one talks about it or if they do, they refuse to see it as unusual.
https://link.springer.com/article/10.1134/S0016793212080063
There are hundreds of studies and papers, textbook also Weathermans Guide to the Sun, Davidson
Summary: Solar particle forcing combined with Earth Magnetic Excursion has much greater impact on global weather than human activity
Suggested reading: Pierre-Marie Robitaille
http://www.ptep-online.com/2011/PP-26-01.PDF
July, 2011 PROGRESS IN PHYSICS Volume 3
A Thermodynamic History of the Solar Constitution — I:
The Journey to a Gaseous Sun
Thanks for the links. While I am pretty much onboard with the fact that there IS climate change, the premise that it is caused primarily by human caused CO2 emissions is still theoretical in my opinion. It hardly ever snows here in central SC. So far this year it has snowed twice. Prior to this year the last snowfall was in 2015.
I have read the man-made carbon-skydumping global warming theorists claim that they predicted that as the polar zones warm up faster than the non-polar zones, that the narrowing overall heat/temperature difference between the polar versus nonpolar zones would lead to jet stream weakening and wandering, and south-wandering jet streams would allow polar-zone air to wander south right behind them even as north-wandering jet streams would allow non-polar-zone air to wander north right behind them.
I don’t know if they really made that prediction or are just trying to claim they made it after the fact. But it looks like that is happening. So you can have super snow under a way-southward dip in a jet stream and PacifiCanada can have super heat under a way-northward dip in a jet stream.
For some time to come, the climate wherever you live will show more peak-and-trough instabliity like that as the Earth Climate System tries to reach some kind of balance with the rising heat loads.
And it will never reach that balance because it is chasing a moving target of ever more higherly rising heat loads on top of rising heat loads.
Unless the ChinaGov decides to surround the planet with a sun-blocking shroud of sulfuric acid droplets all around the earth.
Did the Solar particle forcing combined with Earth Magnetic Excursion theorists predict the last few decades of one-way heatup? Did they predict the meltback of polar and high-mountain ice-features? Did they predict some other things that the man-made carbon-skyflooding warmists predicted successfully?
If you can show links to the same actual predictions made at the same times by the Solar Particle etc. theorists that the carbon skyflooding warmup theorists have made, then one may suppose that the Solar Particle etc. theory has equal predictive validity, and is therefor equally worth taking seriously.
Yes, the giant wheels that influence our climate are many and fascinating. Others include precession, eccentricity and obliquity. They explain much, including why the north star is not fixed and why we have ages like the Age of Aquarius.
We are clearly a contributor to warming, but the extent and materiality of our contribution is still an open question, so I roll my eyes when I hear someone say “the science is settled” because it’s clearly not. Rising temperatures signaled the end of the mini ice age between around 1820-50, well before our contribution to CO2 was material. Climate models basically pick up on that, assume CO2 is a material cause and extrapolate accordingly, which is why they “run too hot” and every short term prediction has failed spectacularly.
A warmer world, whatever the cause, will certainly be a wetter world, and that means more snow and more rain. In a world where fresh water is one of the scarcest of resources, I think that is overall a good thing, but it will need to be managed. We don’t know how weather patterns will be impacted in the future, who will win, who will lose, or how much dislocation it will cause.
I have read that the mini ice age first onsetted some time after the Iberian Germocaust of the Amazon Basin Nations. That mass killoff of millions of Amazon terraformers and terrafarmers let a couple square million miles of inhabited land to go back to forest. That sucked enough skycarbon down out of the atmosphere to reduce the atmosphere’s ability to retain heat. That lead to the cooldown we call the mini ice age.
If that is what happened, then that is an example of human effect on the climate . . . in that case a genuine global de-warming driven by the Germocaust Democide of the Amazonians and their lands’ return to forest.
Do the theorists of ” precession, eccentricity and obliquity” have a record of accurate climate predictions they can point to? If they have such a record, we would all benefit by knowing about it.
SE Pennsylvania is classified as “humid subtropical”, so we have those shitty hot and humid summers followed by a mild to cold winter. As a kid in the 80s and a teenager in the early-mid 90s, I remember summers being less severely sweltering and winters being far more flush with snow. Now summers seem to have oppressively hot and sticky systems that just park over us for most of the season with little respite, followed by winters with sadly dwindling amounts of snow cover and alarmingly mild temperatures. My winter wardrobe lies unmolested for almost the entire winter, whereas I needed hats and gloves and heavy jackets more winter days than not in years prior. Summer clothes creep and linger into autumn far longer than they should.
PA also has one of the largest systems of roads in the US — something like 40k miles. And 25k or so bridges. PennDOT has always been terrible and our roadways are not completely awful to garbage quality, depending on where you are. A lot of the bridges are terrifying to look at from the underside. With more frequent freeze-thaw cycles, it’ll rapidly degenerate into Genuine Third World territory, as opposed to the Third World Threshold state it is now.
Flooding is more frequent. THE AC in HVAC groans more and more under the strain, with spikes in power consumption to match. And the power to consume has to come from somewhere. There is no zeal to invest in renewables here. PA burns coal for about half of its electricity, which ends up being a positive feedback loop for climate change.
The Jersey shore is likely doomed. Dewey Beach, DE and Ocean City, MD are probably likewise facing an extinction event.
There’s the influx of climate change refugees to manage. Maybe someone at the DoD will decide to test the theory of a nuclear winter. Killing millions of “birds” and blacking out the sun with a single, radioactive stone — less sun = less warming = climate change solved, dontcha know? Feeding billions of people is going to be a stretch, so why not kill them all? I’m sure some psychopath at the Pentagon has gamed all this out.
Crops are often particular about their soil conditions and people don’t seem to understand that arable land doesn’t just migrate like they do.
We’re way beyond the tipping point. No one has the stones to admit it.
Is it true that “nuclear winter” as a theory is dead, or is it still limping along?
In the 80’s it certainly wasn’t: https://youtu.be/2xBequjDEX0
Personally, I credit the “nuclear winter” theory – as related to the destruction of the dinosaurs – with shutting down the idea that “limited” nuclear wars could be survived which got some traction with the keyboard warriors under Reagan. When it became apparent that a nuclear war would obliterate most life and all hopes of quickly leaving fallout shelters, enthusiasm for this idea fell off a cliff.
We need a better name for polar vortex eruptions south into the non-polar regions. Since in the prior normal would just keep spinning around the polar end of the earth and now weakening jet streams let a bunch of it sag south here and there, now and then, maybe we should call one of those southward sags by the name . . . polar vortex hernia.
just a thought . . .
Changes in measurement protocols apparently account for some of the apparent increase in US snowfall:
https://news.ucar.edu/14009/snowfall-measurement-flaky-history
Was in the heart of the storm here in Plymouth County, Mass. I’d say we got a little under 2 feet on average, my measurements indicated about 14.67″ on the low end average to 20.5″ on the high end (also averaged from multiple measurements), but with the blowing it is impossible to tell, spots with as few as ten inches, others with as many as 36″ or even 40 inches!
It has, sadly enough, mostly melted today, as it gets into the 40s and 50s (!) tomorrow…. the climate is moving from humid continental to maritime/oceanic here. When I go to inland Maine in the summertime to visit a friend, I can smell something in the air, the way summers used to smell here, something about the beautiful, dry, Canadian high and its pleasant airs…. less of that these days in the summer in coastal Massachusetts, and much more of the Bermuda Low (ugh).
But overall, the increase in storminess is real and noticeable. Nor’easters extend later (into June and even July) and start earlier and earlier (October Nor’easters, big ones where we lose power, were once a true rarity, now are becoming typical).
This commenter is blogwhoring on his own behalf in the comment section of a blogger he just insulted. His link sends readers to an obfuscatory, conspiracy-minded climate denial blog, and specifically, to a post that attempts to trash Yves’ work.
Please allow the narrator voice in your mind to stress the word “attempts” when you read the preceding sentence.
There are no source citations on any of the graphs in Heller’s linked blog post (except one graph at the top, which was excerpted from Yves’ post). His 3 scatter plots of snowfall and precipitation v. temperature have no associated time data, and therefore indicate nothing about the issue Yves addresses above.
Reading the piece was a bit like watching a few elementary school kids playing “science teacher” during indoor recess on a snowy day.
Thanks for the takedown. Have ripped out the policy-violating comment (link whoring is absolutely not on), blacklisted the site, the commentor, and his tag-team friend.
Winter’s around NYC are definitely warmer.
As kids we used to skate on the ponds near our house. Boys playing pick up hockey games. Dogs chasing the puck. The girls twirling in their new figure skates they received for Christmas. For about the last 20 years the ice when it does freeze the ice not thick enough to support skating. There are bigger storms now that dump feet of snow, alternating with storms that produce a 1 or 2 inches of rain-snow-mush.
The most disturbing aspect of climate change occurred this winter.
Insects.
I personally never saw insects outside during January or February. I have seen them November then they reappear at the end of March.
I saw them 3 days in Jan – Feb; stink bugs, a mosquito, and several flies I can’t id.
Here in the Southwest, there’s also the drought. A couple of inches of snow in Albuquerque was the most precipitation we’ve had since October. The cold wave kept temperatures below freezing the next day, the snow blowing around in the dry cold air, a friction-less powder that was slippery to walk and drive on (although it did make for easy sweeping of the walk). The conditions were so extreme that you could spin out at 3 mph, and speeds over 25 difficult to maintain much less control in wind; Albuquerque drivers were cowed. And this was just a few inches, not a particularly heavy snowfall per se or by historic standards. One of the most unusual road conditions I’ve experience, different from an ice storm / black ice.