GLOFs & Jökulhlaups
When I was just a wee nerd, one year at the Ohio State Fair I happened upon a merchant selling packs of playing cards called Magic: the Gathering. I had no idea what they were. My mother and sister, who were with me, had no idea what the game was. But they looked really cool and I was big into collecting sports cards, so I purchased a pack. I still remember opening it and seeing the first card, which was called Killer Bees. I read the cards and the confusion only deepened, but I was hooked. The art, the flavor, the intrigue, they were all fantastic.
Almost three decades later, Magic is still going strong, a rarity among games of this sort. Despite the pushback on gaming from a lot of adults, Magic actually fostered my brain in a lot of ways. Mathematics, abstract planning, synergy, resource management. The game was a great way to learn these attributes, but one thing continually sticks out to me more than any of them: vocabulary. I can’t tell you how many times I’ve known a strange word because of the game. The creators are big on using large and weird words. I have seen them on SATs, in trivia, in English and science classes. If I had a dollar for every time I’ve uttered “Thanks, Magic: the Gathering!” for knowing an unusual word I could probably afford an Alpha Black Lotus (~$100,000).
Many of the wonderful terms are nature-centric. One of the early examples I recall is a card called Jokulhaups. Fittingly, it’s from a set called Ice Age. When I was 14, I had no idea what this word could possibly mean, but the exposure allowed me to look it up.
When my friend Alan pinged me with today’s topic and I started to research it, I was delighted to see the intersection with one of my favorite words.
Kenai Fjords is a National Park on the southern coast of Alaska. It contains at least 38 glaciers, the largest of which is Bear Glacier. Six and a half miles above the terminus of the glacier is an interesting feature: an ice-dammed lake. The technical term for this formation is a proglacial lake. Unlike a normal pool, these types of lakes form because water gets trapped by ice from a glacier. Most regular lakes are fairly stable. They can flood and they can occasionally produce major problems downstream, but that sort of behavior is rare. Ice-dammed lakes, however, are ephemeral and prone to major geologic actions.
When an ice-dammed lake overflows or ruptures, the water gushes forth in what is known as a GLOF: a glacial lake outburst flood. These events can have catastrophic results, as they release water quickly. In October 2010, at the terminus of Bear Glacier, the lagoon rose by 6 feet! This footage delta doesn’t sound that impressive to you? Well, take a look at the size of the lagoon:
According to the National Parks service, another GLOF in 2014 “caused Bear Glacier Lagoon to breach the moraine which separates it from Resurrection Bay. After the outpouring of water and silt into the bay, lagoon levels dropped dramatically and caused increased calving at the Bear Glacier terminus.” They claim over 2,600 Olympic-sized pools can flow from the lake each day when it breaks. Fortunately, in Alaska, these events happen in non-populated areas and often in the seasons when adventurers have vacated the region.
The ice-dammed lake at Bear Glacier is nearly an annual occurrence. Despite the predictability, scientists have not had great access to study it. Recently, the NPS installed a time-lapse camera near the lake in hopes of learning about the timing of the outbursts. During the month of November, the cameras captured a GLOF in time-lapsed motion!
The following images are from, respectively, November 4, 10, and 13.
Rangers from Kenai Fjords National Park claim these images are the first instance of observing the lake draining in “real-time,” a boon for studying the phenomenon. It’s incredible to realize that the lake was 800 feet deep. In a week, it was drained!
Of course, GLOFs are not limited to Alaska. In fact, the OG term for these types of events is, you guessed it, jökulhlaup! A jökulhlaup is an Icelandic term for any large and abrupt release of water from a subglacial or proglacial lake or reservoir, though it was initially tied to only those releases related to volcanic activity. The word literally means “glacial run.”
Some of the historical instances of jökulhlaups are truly frightening. Lake Agassiz was an enormous glacial body, greater than the size of all the modern-day Great Lakes combined. Outbursts from this lake had an extreme influence on the global climate. Today, many glaciers in Iceland have dramatic consequences. Mýrdalsjökull, an ice cap in southern Iceland, is prone to behemoth jökulhlaups that can discharge up to 400,000 cubic meters of water per second. An Olympic-sized pool is 2,500 meters cubed, for reference.
Seeing this mangled piece of metal makes me understand why the game designers of Magic titled a card that destroyed artifacts, creatures, and land the way they did! And while I have to give them props for the flavor and mechanic intersection, they actually managed to misspell the term. There’s a missing “L” in there. Whoops.
Further Reading and Exploration
Jökulhlaups – National Parks Service
Bear Glacier Ice-Dammed Lake Webcam – NPS
Bear Glacier: Glacial Lake Outburst Flood – NPS
Risk and Recreation in a Glacial Environment: Understanding Glacial Lake Outburst Floods at Bear Glacier in Kenai Fjords National Park – NPS
Bear Glacier Lagoon – NPS
Entire lake vanished in days at Alaska national park – The Sacramento Bee