Why has there been so much snow this year?
Look, I don’t need to tell you. The numbers have been absolutely ridiculous. Utah’s snow-water equivalent — a measure, basically, of “how much water would you get if you melted the snow at an average of all of the measurement stations” — has reached 30 inches for the first time on record.
For further example, Alta Ski Area reached 874 inches of accumulated snowfall this week, has 20 feet of snow currently on the ground, and found itself unable to accommodate the skiers who want to use the mountain, staying closed due to avalanches in the area and on Highway 210 up Little Cottonwood Canyon.
But why? you ask. What’s going on? What is it about this year that has led to the most outlier winter of our lives? I did my best to find out.
Randomness
OK, I know. Starting out this explanatory column with the “randomness” subhead is the kind of thing that makes you want to turn your page, close this browser tab, or simply just unsubscribe to The Salt Lake Tribune in search of a news publication that will give you better answers. Wait, don’t.
Meteorologists and climatologists all essentially agree: When you look at the year-by-year weather output in a specific location over a whole season, the results come down to airflow systems that are so chaotic that they’re impossible to model with much confidence more than two weeks into the future.
That’s not exactly “randomness,” but, in practice, it is. Think about flipping a coin. Theoretically, if you modeled the exact specifications of your coin, the location and vector of the force your thumb put on the coin during the flip, the air resistance conditions as it tumbled through the air, and the physics of the surface the coin landed on, you could predict the outcome of coin flips. In reality, all of it is too hard, so we treat a coin flip as random — just like figuring out long-term weather.
University of Utah professor Jim Steenburgh used a different analogy in his blog post titled “What the Hell Is Going On?” this week. He compares atmospheric conditions to those of an out-of-control fire hose: The water is being sprayed somewhere, but predicting who is going to get sprayed isn’t easy.
It’s possible that our modeling systems or understanding will improve someday so that we’re able to predict the outcome of coin flips or loose fire hoses or weather seasons, but we’re not there yet.
Long-term climatological conditions
Over the short run, meteorologists are able to use atmospheric conditions to make relatively impressive weather forecasts. During a whole ski season, though, the atmosphere changes all the time. As a result, they have to rely on whatever longer-lasting measurements are available to try to guess at the weather, even if they’re just small factors in the overall equation.
What we do have are oceanic temperatures. For the past couple of years, water temperatures have been a few degrees colder than usual in the eastern part of the Pacific Ocean near the equator, a circumstance called La Niña. You’ve probably heard of it.
La Niña usually means less rain in the Southwest — closer to that oceanic cold spot — and more rain in the Northwest. So before the season, that’s what climatologists predicted. Utah, by the way, was right in between, with an equal chance of being wetter or drier than normal. But the forecasts are super probabilistic. Even when experts have an inkling going one way, it’s more of a nudge than a determining factor.
(https://www.climate.gov/media/14931)
This year, the expected highs and lows in the atmosphere shifted hundreds of miles off their expected La Niña averages. Hundreds of miles is tiddlywinks in the scope of the world but makes a big difference in whether Utah receives cold and snow.
(https://www.climate.gov/media/15146)
Or as U.S. climatologist Tom Di Liberto wrote, “Simply put, when it comes to the winter atmospheric pattern, this doesn’t seem to be a case where the models and forecasters were predicting a dog, and reality was an ice cream cone. It was more like they were predicting an English bulldog, and reality was a French bulldog.”
As an aside, that La Niña was declared over last month.
Maybe it’s just the weeks of snow we’ve had to endure here, but I’m a little less favorable to the climatologists than they are in evaluating themselves. I truly understand the vast unpredictability of the chaotic nature of the systems they’re trying to model, but, frankly, there’s a reality: Even the dogs in Utah have recently resembled ice cream cones. If this is seen as climatological seasonal forecasting success, we have a long way to go.
Longer-term trends
I do, however, want to give credence to the research being done about how the climate is changing overall. Sure, 90% of any given season may be due to shorter-term factors, but humanity’s environmental inputs do clearly matter over multiple years.
In particular, two recent studies from researchers at Utah State University address winters here locally. First, professor S.-Y. Simon Wang contributed to a study on the “Warm Arctic Cold Continent” weather pattern. Essentially, researchers have found that the arctic poles are warming more quickly than the rest of the world is, while also noticing that a bunch of places on the Eurasia and North American continents have had colder-than-usual winters.
The study uses a model to try to show causation — that the warm poles cause changing atmospheric currents, which results in the cold winters. It had been a controversial idea, but the new research shows a mechanism at play. I’ll be interested to see if the work, released in February, gains widespread acceptance among climatologists.
Second, Wang and HongPing Gu, a postdoctoral USU researcher, worked together on another study that examined the historical trend of precipitation in specific Utah storms. To do so, they used a metric called probable maximum precipitation, or “the maximum depth of precipitation at a location for a given duration that is meteorologically possible.”
Gu and Wang found that, for winter frontal storms, the three-hour and 24-hour PMPs for Utah in various locations have been increasing from 1981 to 2018. In other words, winter storms have been dropping more rain or snow when they do come around, even though they’ve been less frequent in recent years. Interestingly, 24-hour PMPs for monsoonal summer storms did not show the same pattern. They’ve seen less extreme precipitation overall.
Deities
As many have noted, the exceptional winter has come after two notable spiritual developments.
One, Gov. Spencer Cox continued to ask Utahns to pray for snow and rain this winter. Interestingly, it turns out that prayer — both when someone has prayed for themselves and when someone has prayed for outside outcomes — has been scientifically researched in a number of health disciplines, with positive, neutral and negative effects found in various studies. The meta-analysis was unable to determine consistently when prayer worked versus when it didn’t.
Second, the whale statue in the 9th and 9th neighborhood of Salt Lake City was installed last year. As noted by our reporter Alex Vejar, many locals have credited the sculpture for the severe winter. While the article this week quoted Dave Amirault, a Sugar House resident, as jokingly saying “it’s 100% the whale” and “it’s been scientifically proven,” no such scientific study could be found on the influence of whale statues on local climates.
But, hey, we’re struggling for a reason for the season. We’ll take anything at this point.
Andy Larsen is a data columnist for The Salt Lake Tribune. You can reach him at alarsen@sltrib.com.
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