SSI x Edges of Earth: We Went Glacier Diving in Alaska
October 26, 2024
Some of the most extraordinary dives happen when you least expect them. You might witness something you never imagined, like a squadron of mantas or a lone whale shark gliding through the depths. While some divers chase these majestic creatures, others focus on the tiny critters hidden in the muck, barely visible to the naked eye. For me, as my diving journey evolved, I found myself seeking a different kind of extreme: the cold, and in time, diving in Alaska.
The Journey to Glacier Diving in Alaska
You might wonder why anyone would choose to dive in cold water, and how this type of dive could possibly be fun. And quite honestly for me, it definitely was not an instant love affair. Getting to a point where I not only enjoyed cold-water diving but actually looked forward to it took time, patience, and serious dedication. It is not something you just jump into—it requires mental and physical preparation. Cold-water diving is definitely not for everyone.
That said, there are places that can ease you into it, and then there are destinations that should be reserved for when you are truly ready. Alaska, for instance, is one of those places you want to wait for until you are fully prepared, mentally and physically. For me, diving in Alaska was one of the most highly anticipated experiences of our Edges of Earth expedition trail, and I spent three intense weeks of training to get myself ready for what would be some of the most extreme diving I have ever experienced.
Our goal in Alaska was to dive in glacial melt pools that formed during the summer months, created by the melting ice.
We were going diving in Alaska at Matanuska Glacier—one of Alaska’s largest and most accessible glaciers—and would be diving once a helicopter dropped us off right on the ice. The plan? To plunge into near-freezing freshwater pools that would exist only briefly, as glaciers constantly shift and evolve, even daily. Much like snowflakes, the pools we were diving in would never exist again in the same way, making us among the few to ever experience this specific location at this exact moment.
To prepare for such an extreme dive, we needed at least 30 hours of recent temperate water diving and over 10 hours of cold-water diving in the days leading up to the glacier. This preparation was essential to acclimate ourselves to what we would face. Clocking the 30 hours was the easy part—we did it in wetsuits, diving up and down California’s coast and into the rugged waters of the Socorro Islands, about 30 hours by boat off the Baja’s coast. Exposing ourselves to the cold was the best way to build tolerance and get ready for diving in Alaska.
It was not until we reached Canada that we began to experience what "cold" really means when it comes to diving. We were plunging into waters ranging from 7°C to 13°C (44°F to 55°F) as we made our way from east to west, but this was still a far cry from the 0°C to 1°C (32°F to 34°F) we would face at Matanuska.
Cold-water diving does not allow for shortcuts—you have to fully commit to the process, which includes mastering drysuit diving, a skill that takes your diving expertise to a whole new level. Cold-water dive pros will tell you that gear is everything. It is not just about staying warm but also knowing how to use your equipment well. The difference between diving wet and dry is significant, and choosing the right drysuit comes down to preference.
For example, you could go with a trilaminate shell suit, which allows for more layering underneath, or crushed neoprene, which requires fewer underlayers and feels more like a traditional wetsuit. Both options have their pros and cons, but both need proper training and lots of practice.
In wetsuit diving, a layer of water between your skin and the suit keeps you warm, while in drysuit diving, it is the air you use to inflate the suit, as well as the layers you wear underneath, that provide insulation. I opted for a crushed neoprene suit since it offers some insulation even when wet, and as an always-on explorer, I needed something that required fewer layers and less gear overall.
After legendary cold-water dives up and down the Vancouver Island coastline—from Victoria to Nanaimo to Campbell River—I was starting to feel as prepared as I could be for diving in Alaska. We had encountered some of Canada’s most iconic marine life, including Giant Pacific Octopus, sea stars, seals, and enormous anemones, which helped distract us from the biting cold.
With each dive, my mindset began to shift from simply enduring the cold to fully embracing it. I realized that the more I dive in these challenging environments, the more I discover and learn, pushing my skills in ways I never expected.
We were heading to a glacier site where fewer than 50 people had ever dived.
Matanuska Glacier, located about 100 miles northeast of Anchorage, is 27 miles long and 4 miles wide, with its terminus feeding into the Matanuska River. This valley glacier slowly moves at about one foot per day, and it can take up to 250 years for ice to travel from its formation point to the glacier’s end. It was wild territory, and I was both nervous and excited to see what awaited us.
After a two-hour drive north of Anchorage, we passed Matanuska Glacier, sprawling out into the valley in a way that was both breathtaking and intimidating. Just seeing it made me feel cold. We arrived at the helicopter launch and immediately started gearing up—we were racing the clock to make the most of our time out there.
Thick clouds had rolled in the minute we pulled up to the landing strip, which meant we would be cold not only in the water but also would remain cold once we got out, with no sun to provide any warmth. The helicopter flight to the glacier was a quick 10-minute ride, but with all our cold-water dive gear, we had to split up to balance the weight.
The flight itself was one of the most incredible scenic experiences I have had. We flew over lush green mountains and wildflowers, and then, in an instant, we were hovering over black, white, and blue ice. The pools below looked surreal, almost otherworldly. Despite the heavy cloud cover casting a grey hue over everything, the view was stunning.
Once we landed, the silence hit. The helicopter left, and we were completely alone, on the brink of glacier diving in Alaska. We stood on ancient ice, with the sound of quiet glacier water flowing all around us. It was clear that the glacier itself was alive.
The biggest concern about diving in Alaska was our equipment freezing up, especially the regulators, which were prone to freezing and then free-flowing. To avoid this, we had to manage our air intake carefully, using only what was necessary.
Staying calm and maintaining relaxed breathing was crucial, though not exactly easy in 0°C (32°F) water.
Additionally, we manually inflated our BCDs to prevent any potential hose issues during the dive. Our time in each of the two glacier pools was limited to 20 minutes—no one had ever lasted much longer in these extreme conditions.
The glacier water was constantly moving and changing before our eyes, making it drinkable (and it was the best water we had ever tasted, straight from the source!) The first plunge was the toughest, as the cold hitting our bare faces was shocking. My regulator immediately started to free flow, so we spent some time on the surface, sorting things out before descending—and the cold just sunk in hard.
The deeper we went, the water’s blue hues shifted into increasingly deeper shades; the ice formations were untouched and pristine.
Small crevasses formed around us as the glacier continued to move. It was clear this place would look completely different in just a few weeks.
In terms of technique, glacier diving in Alaska was not much different from a typical freshwater dive. We needed less weight, but with all the gear on, we still had to pack some lead. Despite the layers of insulation, the cold was relentless. Still, it was easy to forget the freezing temperatures when we were diving through something so spectacular. The hardest part was not the cold—it was leaving. After nearly five hours on the glacier, it felt like we had only been there five minutes.
Diving in Alaska is not just about glaciers; the underwater world here is vast, with marine life and dive sites that rival the best cold-water destinations. Beyond alpine lakes and glacial pools, Alaska offers a range of ocean dives, from exploring historic shipwrecks to swimming with seals and uncovering remote islands off the coast.
Yet, no dive can truly compare to the experience of diving on a glacier. It is a challenge for any cold-water diver and a stark reminder of the alarming rate at which glaciers around the world are receding. Glaciers are one of those key indicators of how rapidly the planet is warming. According to NOAA, glaciers globally are shrinking or even disappearing at an unprecedented rate.
These ancient ice formations not only cool the planet but also provide essential drinking water and life for all of us.
Out of the 100,000+ glaciers cataloged in the World Glacier Inventory, only about 60, known as "climate reference" glaciers, are monitored regularly to assess climate impacts. Data up to 2022/23 shows that these glaciers have lost nearly 26 meters (94 feet) of ice—an alarming rate of loss. Without glaciers, the consequences would be dire: reduced drinking water, rising sea levels that threaten coastal cities, and a loss of critical habitats for ice-dependent species.
Traveling to Alaska and witnessing the glaciers up close with the experts who monitor them daily makes the urgency of the situation impossible to ignore. The evidence of change is striking, even while driving down the Glenn Highway. You can see it in the striations etched into the rocks, the sedimentary layers, and the braided Matanuska River carving through eroded soil.
Matanuska Glacier is losing about a foot (0.3 meters) of ice every year, and the signs are everywhere—thinning ice, expanding moraines, and shifting landscapes. These stark features are a powerful reminder of nature’s fragility and the critical need to protect it before it is too late.
If glacier diving in Alaska is now on your list, it is still possible—with the right preparation. Cold-water diving takes dedication, but SSI courses can get you ready for the challenge. The pinnacle of cold-water diving awaits in Alaska, but protecting these ecosystems depends on the choices we make today. When it comes down to it, both our actions and our abilities in the water are key to preserving these incredible places for future generations.
Are you ready to embrace the cold for the ultimate dive?
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Andi Cross is an SSI Ambassador and lead of the Edges of Earth expedition, highlighting stories of positive ocean progress and how to explore the world more consciously. To keep up with the expedition, follow the team on Instagram, LinkedIn, TikTok, YouTube, and their website.