Declining Snow and Ice Part II: Future Projections

In the previous post we examined recent trends in snow and ice including glaciers and seasonal snowpack.  Here we look at future projections.  

I use the word projection rather than forecasts because projections explore "what-if" scenarios whereas forecasts try to predict a future outcome.  For climate projections, the primary what if scenarios are often based on future greenhouse gas emissions scenarios or pathways and in some cases socioeconomic pathways.  These include, for example, moderate emissions pathways in which greenhouse gas emissions peak during the mid-21st century, so-called "business as usual" scenarios in which emissions increase through the 21st century, and others.  

These scenarios produce increases in globally average temperature over pre-industrial values.  For instance, the moderate-emissions scenario produces an increase of about 2°C and the high-emissions scenario produces an increase of about 4°C.  These are sometimes referred to as global warming levels (GWL) and I'll be using those for this post.  For a given global warming level, the amount of warming for a region may differ from the global average and in the case of Austria (and Utah) the amount of warming is greater.  

We will start with glaciers in the European Alps based on work presented by Zekollari et al. (2019).  If interested, I have a deeper dive on this topic (see The Fate of Alpine Glaciers).  The graph below presents the recent (prior to 2017) and projected future volume of glacier ice in the Alps, the latter under four scenarios.  One is the committed loss, which is an estimate of the future loss of glacier volume if the climate stabilized around what occurred from 1988-2017.  The others are with an additional levels of global warming.  

Source: Zekollari et al. (2019), with annotations added

Because the Alpine glaciers are currently out of equilibrium with the rapid warming that has occurred in recent decades, they will continue to shrink even if the climate remains unchanged relative to 1988–2017.  Under such a scenario, the volume fraction of glacier ice would decline about 40% from 2017 levels.  Increasing amounts of glacier loss occur for higher global warming levels.  Under high global warming levels, nearly all of the glacier ice in the Alps is gone by 2100 (see red line) with the only glacier remnants remaining in the high terrain region from Mt. Blanc to Zermatt and the Swiss Jungfrau.  

Moving to snowfall, below are estimated changes (from 1981–2010 to 2070–2099) in the water-equivalent of snowfall for the Alpine region (September to May) as a function of elevation under a global warming level of ~2°C and a global warming level of ~4°C.  Similar to recent trends, declines are very much elevation dependent and largest in the lower elevations and smallest in the upper elevations.  For the 1000-1250 m elevation band, the various models call for declines of 15-40% for 2°C of global warming and 40–60% for 4°C of global warming.  Declines are larger at lower elevations and smaller at upper elevations.    

Source: Frei et al. 2018, with annotations added.

Another perspective is provided by trends in the number of days with at least 30 cm of snow on the ground.  The graph below is now for the Austrian Alps, which are a bit colder at a given elevation than the western Alps and the Italian Alps.  Again, the percentage changes are elevation and scenario dependent.  For the 1500-2000 m elevation range, snow cover of at least 30 cm persisted for about 175 days a year.  For 1991-2000, this has declined to about 130.  For a global warming level of 2°C, that drops to about 110 days with additional declines for larger global warming levels.  At upper elevations, the percentage declines are smaller, but there are still declines.  

Source: Formeyer et al. (2025, https://aar2.ccca.ac.at/chapters/1) with annotations added.

Finally, groups have estimated changes in ski resort snow reliability based on projections like those above but also considering changes in snowmaking conditions and projected advances in snowmaking capacity.  In the case of Austria, the regions that see the largest declines in snow reliability, especially under a high-emissions scenario (right figure below), are in eastern Austria (the Austrian States of Lower Austria, Upper Austria, and Styria) and the northern Alpine Rim in western Austria near the German border.  These are areas where ski resorts are at low-to-moderate elevations.  

Source: Steger et al. (2021, https://www.sciencedirect.com/science/article/pii/S2213078020300542) with annotations added.

The highest snow reliability persists in the inner Alps in western Austria near the Italian border where the terrain is high (green ellipse), and in the Arlberg region in western Austria near the border between the Austrian states of Voralberg and Tyrol (red ellipse). In the case of the former, there are several resorts with substantial terrain above 2000 meters (Kaunertal, Pitztal, Sölden, Obergurgl, Ischgl), whereas the latter is currently Austria's snowiest region and will likely maintain some level of snow reliability even as a greater fraction of wintertime precipitation falls as rain instead of snow.  This does not mean those regions will not see declines in natural snow reliability and hours with favorable snowmaking conditions, but that they are more resilient to warming given their elevation or more abundant natural snowfall.  Everywhere will experience the pain of global warming, but the "competitive advantages" of these regions will increase with time as other regions suffer more.

We will see similar effects in Utah as the high-elevation, snow-abundant terrain around Little Cottonwood Canyon suffers less than lower elevation regions in the Wasatch.  High elevation (and north facing) resorts like Alta and Snowbird will see an increasing competitive advantage in the future, as was evident this past season.  

What I takeaway from this and other research is that there still will be snow and snowstorms in the future, although we can expect downward trends in snowfall and snow-cover duration in most regions. The size of the decline, however, is strongly dependent on the amount of warming, which is tied to future greenhouse gas emissions.  Thus, the fate of snow and skiing are ultimately in our hands.  

Declining Snow and Ice Part I: Recent Trends

One of the things I'm doing while on sabbatical in Austria is revisiting our current knowledge of recent changes and projected future changes to Earth's cryosphere (the frozen water part of the Earth system including ice sheets, glaciers, and snow) and integratig this information into course materials and public talks.  Austria is a good place to do this because there is a great awareness and convern about changes to glaciers and snow here and winter tourism is a significant portion of their economy (as much as 6% of their GDP based on some estimates).  As a result, there's a great deal of useful information concerning changes to snow and its impacts on winter sports and tourism.  

But before taking a close look at Austria, let's take a step back and look at the big picture.  Globally averaged temperatures have increased about 1.4°C/2.5°F above pre-industrial levels and the past three calendar years (2023–2025) were the warmest on record.  In response, the "great melt" has begun, with declines in the mass of the Greenland Ice Sheet, Antarctic Ice Sheet, and glaciers.   

Since the late 1970s, the Greenland Ice Sheet has been losing mass, corresponding to about 18 mm (0.7") of sea-level rise.  

Source: https://climate.copernicus.eu/climate-indicators/ice-sheets 

Similarly, the Antarctic Ice Sheet has been losing mass, amounting in total to about 14 mm (0.55") of sea level rise. The graph below includes mass changes for three regions of the Antarctic Ice Sheet (East Antarctica, West Antarctica, and the Antarctic Penninsula, as well as the cumulative total for the entire continent.  

Source: https://climate.copernicus.eu/climate-indicators/ice-sheets 

Finally, glaciers have lost 9000 Gigatonnes of mass, the equivalent of another 27 mm (1 inch) of sea leel rise.  

Source: https://climate.copernicus.eu/climate-indicators/glaciers

These recent changes cannot be explained by a "rebound" from the Little Ice Age, a period of regional cooling, especially in the North Atlantic region.  Since the 1990s, the loss of land ice has been driven by human-caused global warming.  Additionally, although the contributions to sea level rise may seem small so far, they are an ominous harbinger of things to come. 

Zooming into Austria, temperatures are increasing faster than the global average and have increased 3.1°C/5.6°F since the pre-industrial period.  

Source: https://aar2.ccca.ac.at/technical-summary

The impacts on snow and ice here are very apparent, with the recently released Second Austrian Assessment Report on Climate Change (AAR2) concluding that "all glaciers in Austria have been losing mass and shrinking at an accelerating rate in recent years."  That's somewhat cautious wording.  Instead of shrinkage, the word disintegration is being used increasingly to describe the fracturing and collapsing of some glaciers.  

Austria has an extensive network of snow observations.  They reveal elevation-dependent trends in snow cover with the larget percentage declines in the lower elevations and smallest at higher elevations.  Below are the trends at Austrian stations from 1961–2021 showing statistically significant declines at most stations that increase with decreasing elevation below about 1750 meters.  

Source: Steenburgh (2023, based on data provided by Marc Olefs, Geosphere)

Most Austrian ski resorts have base elevations below 1750 meters and the vast majority below 1500 meters.  

In a coming post, we will look at projections for the future and expected impacts on snow and skiing.  

Austria's "Highest" Ski Resort

Sometime in early April after a day of skiing I discovered that both of my ski boots had developed cracks more than 1 cm in length in their upper cuff.  Not good.  It's the end of the season and I went around town looking for replacement boots, to no avail.  Then I walked into Sport Wolf, a little outside of the main core of Innsbruck. 

The owner, Hansjörg, took great interest in my situation.  He contacted Salomon, who provided me a 40% discount on a new pair (my old boots were at least 6 seasons old and well outside of warranty).  A couple days later they arrived and after an initial fitting at Sport Wolf I'm back in business.  Much thanks to Hansjörg for outstanding service.  

I decided that I should get a couple of hours of skiing in the boots and decided to go to Kuhtai for a few laps on Friday.  It was the closest resort to Innsbruck that is still open and can be reached by bus in about an hour.  

Kuhtai markets itself as Austria's highest ski resort at 2,020 meters elevation.  

There are, however, three caveats to that claim.  First, their highest lift elevation is 2,520 meters, and there are many Austrian ski areas that exceed that.  Second, they actually have lifts that go below 2,020 meters, including one, the Kaiserbahn, which starts at 1,938 meters.  Finally, there are Austrian resorts with base elevations above 2,020 meters (Pitztal Glacier, Kaunertal Glacier, and Mölltal Glacier).  I guess the distinction is that the village of Kühtai sits at 2,020 meters and perhaps that is what is meant by resort.  

Kühtai sits in an east-west oriented mountain pass between the Sellrain Valley to the east and the Neder Valley to the west.  Given it's altitude, it is essentially treeless.  It has south facing terrain on the north side of the pass and north facing terrain on the south side.  

Coverage on Friday was good on for the north-facing terrain, but the south-facing terrain was nearly snow free below about 2200 meters except along trails with snowmaking.  

Looking north to the south-facing side of Kühtai

Looking south to the north-facing side of Kütai

I was told Eileen Gu was was skiing here a couple of weeks ago, but on this day, there were only a few diehards and one Utahn who was testing his ski boots, which fit well.  Hopefully I have a few more days of skiing before this season is over. 

A Front

After about 7 weeks in Austria, I feel very detached from the weather in Utah.  I hear rumors and see evidence of an abysmally bad snowpack and have been sent photos from Little Cottonwood that look like late May rather than mid April.  A look at the SNOTEL data shows every site in the Wasatch, Oquirrh, and Stansbury Ranges at a record low water equivalent except the "plucky" Farmington Lower SNOTEL which is in 3rd simply because of what appears to be a spurious reading of 0.1".  Pretty sad.  

However, I also noticed that there is a cold front coming through northern Utah tomorrow (Thursday) and it should bring a pretty good drop in temperatures.  The 0000 UTC GFS (I'm 8 hours ahead of  you and writing this in the middle of the night Utah time) shows the cold front draped over northern Utah at 1800 UTC 16 April (1200 MDT Thursday).  Salt Lake City is likely to be post-frontal at that time and seeing colder air moving in.  

The front will bring a substantial drop in temperatures.  At 700-mb (roughly crest level), temperatures fall from around +2°C this (Wednesday) afternoon to -12°C by Thursday evening.  The temperature at the Salt Lake City International Airport has not dropped to or below freezing (32°F) since March 15.  We should be able to do drop to at least that by Friday Morning when the forecast low from the National Weather Service is 30°F with snow showers.  

As advertised by the more recent model runs, the precipitation prior to, during, and immediately following the frontal passage is not all that prolific.  For Alta-Collins through 12 AM (Midnight) MDT Friday the 06 UTC 15 April HRRR is producing 0.51" of water and 7.9" of snow.  Through the same time, the 00 UTC 15 April GFS is producing a more pathetic 0.3" and 5" of snow.  Five members of the 0000 UTC RRFS Ensemble have 0.5" of water and 7" or less of snow through 0000 MDT Friday (06 Z 17 Apr), but there is one member with a more enthusiastic total near 0.8" of water and 12" of snow.  

Perhaps such a dust-on-crust event will be enough to get your heart rate up.  If not, one has to hope for one or two things.  One is that the period around and including the frontal passage on Thursday is more productive and comes in higher than most of the models and maybe near or above the wettest RRFS member.  The other is that the cold, post-frontal northwesterly flow is productive Thursday night and maybe Friday morning, with either orographic or lake-effect snow.  It's a bit soon to have confidence in the post-frontal crapshoot, so monitor forecasts while I stare at the Alps. 

A Little Tyrolean Culture

It's hard to find the Greatest Snow on Earth in Tyrol, but it's easy to find great mountain culture.  Innsbruck is a college town, with around 28,000 students enrolled at the University of Innsbruck.  The ski and outdoor stoke here is high, similar to Salt Lake.  You see kids with skis everywhere, with bikes a popular mode of transport to the bus and train lines that can take you to the resorts or touring spots.  

Nobody blinks an eye when you carry your skis through the grocery store or stop at a bakery and leave them by the front door.  Busses and trams, the latter called "light rail" in the US, are everywhere and those going to resorts are often packed with skiers and snowboarders.  

Meanwhile, the lower and mid-elevation trails on the south aspects above town have melted out and there are many bikers and hikers going to mountain huts for food and libations.  The photo below is from Rumer Alm on Sunday, popular with everyone from young families to 80-somethings who either hike up or ride an E-bike.  

A bit lower than that is Arzler Alm, which was also packed on Sunday and even offers up a playground.  

Falling under the category of you won't see this in Utah, Rumer Alm has a self-serve beverage stand.  Open up the door and grab whatever you need, including alcoholic beverages, even when they are closed.  Just drop your payment in the box.  The only security is a camera.  

On an unfortunate note, we did see a mountain rescue by the Bergrettungdienst (Mountain Rescue Service) of Innsbruck.  This was in a hiking and biking area and we were not sure if there was an injury from a crash or slip or sudden illness.  We can all be thankful for the extremely capable professionals who perform these rescues.  We hope for a speedy recovery for whoever was affected.  

For those coming to the Alps, it's worth noting that almost any mountain rescue here requires payment.  Even a sled ride off the ski hill will probably cost you 50 euro and if medical care is needed on the hill probably 250 euro.  Other transport even more.  Membership in Alpenverein Österreich (Austrian Alpine Club) includes a number of benefits for rescue costs and is a good investment if you are recreating here (see http://alpenverein.sichermitknox.com/service) and don't have coverage through other channels.  

If anyone from Innsbruck is reading this, I will be giving a public talk on mountain weather, climate change, and finding deep powder at the University of Innsbruck at 1900 on Thursday 23 April.  There is a request for registration at https://www.uibk.ac.at/events/2026/04/23/secrets-of-the-greatest-snow-on-earth, but if you read this at the last minute, you won't be turned away at the door.  

Austrian Powder

This year has been a down year for powder for me and possibly you too due to the substandard season in Utah. 

Here in Innsbruck, however, we had an Austrian powder day today on the Stubai Glacier.  With only a few cm, it wasn't a deep day and I should call it dust on crust, but beggars can't be choosers in 2026.  Some decent turns were had in areas favored by the wind.  

Clear days in the Alps can't be beat.  The back side of Stubai has great views of western Tyrol.  The highest peak in the photo below is the Wildspitze, the second highest peak in Austria.  

Utahn's are familiar with morning powder in the mountains and afternoon summer in the valley, but the situation in Tyrol is even more extreme.  Stubai Glacier reaches 3210 meters (10,500 feet), comparable to the top of Alta and a bit below the top of Snowbird, but Innsbruck sits at 574 meters (1883 feet), much lower than Salt Lake City.  So we had morning powder with a summit temperature of -3.2 C (26F) at 8:50 AM and then an afternoon high in Innsbruck of 23 C (73 F).  It's 8:38 PM here now and we have the apartment windows open and are lounging in shorts and T-shirts.