The find the short story in this week's Challenge, I started with the straight-forward query first, hoping I might find something that matched quickly:
[ short story frozen lake space beneath ice ]
which took me to several pages, all of which told me that this was a short story by Rick Bass entitled "The Hermit's Story," in a book by the same name (The Hermit's Story, Haughton Mifflin, 2002, which has 10 stories in all). Once I had this, I was able to read the story which includes this description of the space beneath the ice:
“..she took one glove off and eased her bare hand down into
the hole. She could find no water, and, tentatively, she reached deeper.
Gray Owl’s hand found hers and he pulled her down in… there was no water at
all, and it was warm beneath the ice.
“This happens a lot more than people realize,” he said. “It’s not really a phenomenon; it’s just what
happens. The cold snap comes in October,
freezes a skin of ice over the lake—it’s got to be a shallow one, almost a
marsh. Then a snowfall comes, insulating
the ice. The lake drains in fall and
winter—percolates down through the soil… but the ice up top remains.”
“…The dry lake was only about eight feet deep…”
Once under the ice, Gray Owl and Ann explore a kind of magical place that's sheltered from the deep Canadian winter cold by a sheet of ice, with marsh grasses and pockets of methane that would occasionally catch fire making “…explosions of brilliance, like flashbulbs, marsh pockets
igniting like falling dominoes, or like children playing hopscotch…”
And while that's a brilliant description, we don't yet know if this is a real phenomenon, or if it's a great story metaphor, a kind of special place that's removed from our ordinary, sublunary world.
I started my search for this mysterious ice-covered dry lake (and what it might be called) by searching for:
[ air gap frozen lake ]
which led to many pages that have some information. Unfortunately, at this point, it's just click and read through the content. I'm looking for a web page that describes the ice and an air gap to the bottom of the lake.
Like others, I read about subglacial lakes that can drain out, leaving an ice roof that can then collapse, although that doesn't sound like what we have here, although it does seem really interesting. (As reader Verda Stelo points out, this kind of drainage can leave pretty large gaps or tunnels in the glacier, though the bottom of the air gap would be more glacier, and not marshy lake-bottom.)
I don't have the scale for this image, but it looks to be fairly large.
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A subglacial lake surface can collapse, leaving a depression in the snow. Aerial photo taken in Greenland. P/C Gizmodo. |
With this query, I also found the source that Debra Gottsleben found: Reading the Short Story which tell us that Rick Bass was inspired to write his story when he heard about a lake with ice on top where the water below had drained out, leaving a gap. (But the blog post doesn't clarify whether or not this actually happens at the scale we're looking for.)
Then there's the frost heave idea, pointed out by Chris who found a technical paper on frost heaves, which could heave up the bottom of a lake enough to leave a gap. But the paper says the max amount is around 30 cm, which isn't anywhere close to the 8 feet mentioned in the book.
The book describes Gray Owl as falling through the ice after walking on it for a bit. That implies a certain kind of structural strength to the ice. It was strong enough to support him for a while, but then thin enough to break under his weight.
This led me to search for:
[ ice safe thickness for walking ]
and I learned that 3 inches is usually considered the safe thickness for walking. So the ice Grey Owl broke through was less than 3 inches. BUT, remember that this ice didn't have any water beneath it! That is, this is the situation:
The ice that Gray Owl is walking on is supported all around the edge of the lake, right? So the structural strength of the ice is going to be limited by how far it is between the lake edges. Ice is pretty heavy and isn't that strong when trying to support a wide gap. In other words, if the lake is 100 yards across, and the middle is 8 feet deep, that's a LOT of ice weight to support in the center.
We could probably do a bit of fancy math with structural equations (after looking up the shear strength of ice--if you're curious, I recommend the highly technical, but fascinating, Ice Handbook which tells you how to calculate all the stresses and loads). The bottom line here is that to support a shell of ice over a drained lake without any internal additional support structures, you'd need the ice thickness to be.... well, let's just say it's MUCH thicker than it would take for a man's weight to break it! This is starting to sound a bit unlikely.
I kept looking for more web documents that describe air gaps beneath frozen lakes and ended up finding an interesting resource after going to page 2 : Lake Ice Glossary, which defines MANY terms for ice, including a few ones that sound plausible.
I learned that Dry shell ice is a shell of ice that covers a "puddle" that has drained away.
Then there's Soufflé Shell Ice, which is a kind of dry shell ice that forms when deep puddles drain in cold conditions. This can create a relatively unusual form of shell ice that typically has a crust on top and a supporting matrix of ice flakes underneath.
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Soufflé shell ice forms an air gap with a "soufflé" of supporting thin ice crystals... It can be over 1 foot thick from top to lake bed. P/C Lakeice Glossary. |
It seems pretty clear that soufflé shell ice could be the inspiration for the dry lake bed of the short story, although it probably wouldn't be quite as clear and empty as described in the story, but filled with a light matrix of ice flakes that give support to the ice above. It would be quite an extraordinary event to have an ice shell that covers a lake large enough to be 8 feet deep AND wide enough to have a thin shell that can support a man's weight, yet one that's still breakable by Grey Owl.
Two things strike me about this Challenge.
First, the term "soufflé shell ice" is ONLY used at the Lakeice site, and doesn't seem to be used anywhere else. The site seems fairly authoritative (its depth of coverage and documentation of different kinds of lake ice is impressive), but the authors of this site might have coined an idiosyncratic term that's not widely used elsewhere.
Second, given ALL of the research that goes into ice (there are millions of results when you search on Scholar), and all of the specialized vocabulary on the topic of ice, properties of ice, and the structures it forms (see glossary of ice terms), it seems strange that there does NOT seem to be a specialized term (other than at Lakeice) for this phenomenon.
A few examples:
Sastrugi Sharp, irregular, parallel ridges formed on a snow surface by wind erosion and deposition.
Polynya Any non-linear shaped opening enclosed by ice. May contain brash ice and/or be covered with new ice, nilas or young ice; submariners refer to these as skylights.
Grease ice A stage of freezing, later than that of frazil ice, in which the crystals have coagulated to form a soupy layer on the surface. Grease ice reflects little light, giving the sea a matte appearance.
Sermik A body of ice (usually with some firn) formed by the metamorphosis of snow, lying wholly or largely on land, and showing evidence of present or former flow.
Search Lessons
Of course, that doesn't prove this under-the-lake-ice-gap doesn't exist, merely that it's not well documented in the literature available on the web. But I gave this a pretty good shot, checking Google Scholar, newspaper accounts, and I even tried my favorite reverse dictionary to seek out any specialized terms for this... but failed.
But after investing several hours on this, the next step would be to activate my social network, and reach out to either the author (no success so far), or other writers in this area. I haven't started that process, but if I were really interested, that would be the next step to pursue.
It could be the soufflé shell ice that we read about above. I'm not sure that this would be structurally sound enough to support a shell over an 8-foot air gap, but it's a working hypothesis.
For right now, we found the short story (fairly easily too), but have to leave the mysterious space under the lake as part of Bass' lovely story. Maybe soufflé, but as yet still unknown.
If you meet Rick Bass on the road, ask him for me, will you?
Search on!