El Niño & La Niña Explained: How South Pacific Ocean Currents Impact Your Ski Holiday (Or Not ...)
La Niña and El Niño are topics that come up all the time when talking about snow and weather. Talk to anyone interested in hunting out the best snow conditions - which is any skier or snowboarder, basically - and they will have have about it themselves or swear by it as a way to predict snow conditions themselves.
These are two sides of the same coin, a variance of South Pacific Ocean currents that flip between warm and cool for a period of time. Their effects on a macro level are well know, but what effect do these two phenomena have on the snow you can expect for your week away this season?
Skiing Unlocked takes a dive into the El Niño and La Niña effects, dispels a few myths, and provides some helpful tips on predicting snowfall along the way.
What Are El Niño and La Niña Effects?
Throughout the world's oceans, there are a series of currents of warm or cold water that are constantly flowing and cycling around, driven by fluctuations in the Earth's temperature and the rotation of the globe.
Most of these are fairly static, and are seen by us in a couple of different ways. In Pixar's Finding Nemo, the surfing turtles ride a warm ocean current up and down the east coast of Australia, and both Brits and the Irish can thank the Gulf Stream current for brining warm water up from the Gulf of Mexico and ensuring we're not facing cold, snowy continental winters.
The South Pacific Ocean current is a bit of a weird one. Every few years, it flips around, and where it was once transporting cool sea water on its path, it will transport warm sea water instead. The standard, predominant cool pattern is referred to as La Niña when it spikes to cooler-than-average sea temperatures, with the opposite, occasional warm pattern known as El Niño appearing somewhere around every ten years and lasting, usually, for a couple of years before reverting back to La Niña conditions.
What Effect Do They Have on Snowfall?
The cycle of these phenomena have wide reaching albeit temporary effects on global weather conditions. Where once droughts were predominant, rain will come, and where cool, snowy conditions were guaranteed suddenly temperatures will rise and the snow won't come.
The West Coast of the USA is a really good example of the local impacts of this cycle. Under La Niña, the shift in storm angles up and down the Pacific Coast means that the Pacific Northwest generally gets really good snow throughout the winter, whereas in El Niño winters, it will be California, the Sierras and Southern Colorado that gets most of the good stuff.
The effects can be seen in Europe too. Warmer conditions under El Niño years has made the region - especially more coastal climates such as the French Alps reliant on sporadic, large dumps of snow for good times, rather than steady, consistent precipitation in cool conditions.
Is This Cycle a Guarantee of Snow in a Particular Place?
An El Niño cycle is often brought up by skiers and meteorologists attached to the phrase "... this will be the best season ever".
Is this right? Can you use these cycles to guarantee good or bad snow? The short answer is "absolutely bloody not".
There are two reasons for this, at play on both a macro and micro level.
On a macro level, there is only a very weak correlation between these cycles and an increase in snowfall totals in different areas. It's generally so weak as to not be considered reliable at all.
There are also other things in play at this high level, too. The last two seasons (2022/23 and 2023/24) in the Alps have been a real mixed bag, characterised by dumps of snow and rain and snow in the early and late season, and long dry periods through the middle. A lot of this may very well be a result of human driven climate change, causing shorter winters, less reliable snowfall, a and a higher snowfall elevation. There isn't enough evidence to pinpoint the last couple of seasons' behaviour on changing patterns in the Southern Pacific.
Secondly, on a micro level, weather forecasts as still terribly inaccurate beyond a certain time period. More than 15 days in advance, weather models have scattered so far apart that they're no longer reliable at all, and generally this scattering begins at 10 days. With a lack of strong correlation between these systems and season conditions, and the still poor long-term weather forecasting models, using them to forecast a dump on your week away is about as accurate as forecasting weather I'll sneeze a week on Tuesday.
So What Can Be Inferred From These Cycles?
Probably not much, at least in Europe. The last two season have been almost identical, with big dumps of snow to open the season followed by long droughts and fine weather throughout January and February. Finally, another burst of snow comes in during March and April, helping extend the winter season.
As if to perfectly demonstrate this point, 2022/23 was the beginning of the end of one of the strongest La Niña cycles in recent memory, and 2023/24 was in the middle of an El Niño cycle.
Similarly, 2022/23 drew some of the best conditions ever for much of the Left Coast of the USA, with Mammoth Mountain, CA recording its highest ever snowpack depth and Utah recording its highest ever snowfall totals in what was an extraordinary year for storm cycles. This is in direct inverse correlation to the expected shift in weather patterns caused by the La Niña effect of this period.
As mentioned earlier, Climate Change is having much the same effect, changing ocean temperatures around the World and influencing weather conditions on a macro level, as well as on a more local micro level. It is hard to correlate which of these is having a greater impact on snowfall and snow quality around the world.
Final Thoughts
This is one of the first times I've been regularly skiing and also aware of these cycles. Despite the complete lack of correlation between them, and the growing influence of other factors, I will be keeping an eye out to see if there is any influence on my skiing this winter. Either way, I won't be listening to the man at the bar who swears this season is driven by El Niño or La Niña.
.jpeg)
Comments