Is lake ice thicker in the middle or close to shore?

[dmayers94]

I'm doing research that involves measuring lake ice thickness w/ a satellite. I'm not actually an ice fisherman, nor do I live by any lakes, so I'm relying on you for help. Is lake ice typically thicker in the middle or edge of the lake? If you have any more specific information on ice thickness, that would also be very helpful. Thank you!

EDIT: The lakes of interest are very large (think great lakes size). They are also many miles above sea level so the temperature is extremely cold in the winter.

[FG Steve]

Ice thickness varies.  For example, a shaded or protected area may form ice first and eventually be thicker.  If that area is near shore, then at first it would be thicker near shore.  If it is an irrigation reservoir then it may fill during the season, resulting in thinner ice near shore.  Some bodies of water have springs, etc., to make thin or bare (water) spots.  I can't think of a dependable rule of thumb to answer your question, and I am interested to read other responses.

[Raquettedacker]

Has to be pretty cold for a couple of months for the middle of a lake to freeze. I'm talking about 15 F and lower.

Interestingly, the center is last to freeze and last to thaw, assuming there is relatively little water flow.

The soil changes temp faster than the water and the frozen soil no longer keeps the shallow water near shore above freezing temps.

The center of the lakes upper most column of water is a much warmer temp than the bottom of the lake and takes longer to freeze, partly due to more sunlight and the volume of water involved. If you want to experience it for yourself, go scuba diving through a thermocline.

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level 2
Peraltinguer
6 points
·
6 months ago
Wouldn't that mean that firstly, when the lake freezes, the ice on the edge is thicker but when it starts to thaw, the middle of the lake thaws slower so that it becomes the thickest part?

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level 3
EngineeredandGeared
2 points
·
6 months ago
This could work in a round pond with no significant water flow. Ice starts forming from the edges and slowly creeps towards the center. Thus at least in the beginning, it would make sense for it to be thicker from the edges than the center (due to having more time to form and thicken). Whether the thickness of ice levels out at some point is a good question. Obviously, water flow, the shape of the pond/lake and the depth at least have an effect on the freezing process.

Having witnessed the ice thawing from a fairly large lake very far up North (above the arctic circle) multiple times, it always seems to happen the same way. The ice melts until eventually there's only a thin sheet of ice on the lake (covering it almost completely apart from the very edges). The next day this massive sheet of ice has shattered into loads of smaller pieces and the remaining ice melts quickly after that. Never seen how quickly the shattering process actually happens as I have always been absent when it has happened (how typical haha).

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level 1
jazzwhiz
Particle physics
6 points
·
6 months ago
Lakes usually freeze in from the edges since the water is usually moving less on the edges. Of course if the ice has frozen to the bottom at some points then it might be thicker towards the middle, but in general I would guess that it would be thinner in the middle.

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level 1
e-9O
2 points
·
6 months ago
Also, less energy is required to for a crystal (ice) to form around or next to impurities (soil) than around more liquid material.

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[ran7ger]

depends alot on the size of the lake, where the wind blows at first ice, shade/sun...tonnes of variables.

[filetandrelease]

there are no other lakes the size of the Great Lakes they range from 264-600 feet above sea level , , and far as ice thickness way to many variables , depths , winds , elevations , first , mid season and last ice  , and temps vary across the US

[Deal Ninja]

I’ll add my old timer’s 2 cents...  In general terms, the shallower the water, the quicker to freeze, AND thaw.  The shoreline area is almost always safer at first ice and almost always the most dangerous at last ice.  But like many others have said, there’s an awful lot of variables.

DN

[KingPerch]

Too many variables in the equation.  I’d like to see some info on how a satellite can measure ice thickness. If it truly can... then the satellite will give you your info. Then, you can share your results with the rest of us.😎

[ActiveTrapChecker]

Trick question?

Deeper the water, the more likely for ice to be thicker. Hard to get a foot of ice in 6” of water.

[Agronomist_at_IA]

Trick question?

Deeper the water, the more likely for ice to be thicker. Hard to get a foot of ice in 6” of water.

True....but the ground water in the soil & soil will freeze under it........so do you consider the "frost" line part of the equation?

[32footsteps]

With the edit of a “Great Lakes” sized body of water and the elevation guideline you have eliminated every lake that exists on earth.

The smallest Great Lake is the 13th largest lake in the world. Of the 13 largest lakes only four or maybe five ever freeze completely over. Then within those four or five none are “many miles above sea level.”

There are lakes that fit the “many miles above sea level” benchmark but those are typically smaller pools created by volcanoes measuring a hundred or so yards across. The highest “large” lake is Titicaca and on the cold end of the spectrum it’s water averages around 50 degrees Fahrenheit.

So yeah....based on the parameters you have placed on the question it is impossible to answer because large lakes at that elevation that freeze over simply don’t exist.

[filetandrelease]

Looks like ol dmayers94 was doing a little fishing 🎣 😜

[dmayers94]

By saying great lakes sized body of water, I didn't mean for everyone to fact check the exact size and think I'm trying to troll. My point was that the lake is large enough so that we aren't worrying about things like shade from trees or 6 inches of water limiting the amount of ice that we can have. The lakes are about 1/4 to 1/5 the surface area of the great lakes. I'm trying to compare ice thickness between these two locations in the lake in the middle of winter:

1) ~ a few hundred feet from shore, when the water is many feet deep so not quite frozen to the bottom
2) the center of the lake when the water is deepest

Is there a general rule of thumb that says which spot should have thicker ice? From the previous comments it seems like there are so many variables that it's impossible to know which spot "should" have thicker ice.

[KinnickResident]

You guys got trolled.

[eriksat1]

Around here the ice seems to be thickest in the middle of the lake mid winter. I think it has to do with the wind blowing all the snow off the the ice in the middle of the lake. Less snow, less insulation, = thicker ice.

[lefty2053]

Many miles above sea level? What where?

[dmayers94]

Thank you eriksat for your useful response. Since everyone is so fixated on which lake this is, it's Lake Namtso in China. It is about 3 miles above sea level and is 1/4 the size of Lake Ontario in surface area.

[Deal Ninja]

Given the criteria dmayers has presented, I would say it’s still a crap shoot, but what the hey, here goes...lol  Shore ice forms first, but as the ice thickness grows, the rate of growth slows to the point that theoretically the ice thickness at the center of the lake would catch up to the shore ice and both would be very similar in thickness.  This assumes A LOT; that wind effect, snow cover, sun exposure and water current, etc., etc. are equal at both locations.  Also as ice reaches toward the lake bottom near shore, radiational heat from the lake bottom could retard ice growth to the point that the center lake ice could surpass it in thickness if enough deeper...  I’m also assuming that no thaw-refreeze cycles  have occurred.  If that were the case, I would definitely say the center lake ice would be thicker. 

I believe we’re all correct when we tell dmayers that that there are too many variables to speculate with any accuracy without knowing all of the specific details.

I don’t know if we’re helping you or not sir, but I know we’re giving it our best shot.  lol

DN

[masoneddie]

Interesting topic Dmayers and welcome to the Shanty!   
One small detail you left out, is that Lake Namtso is also a salt water lake...one more thing to throw in your think box guys... 
https://en.m.wikipedia.org/wiki/Namtso

[lefty2053]

Ice on the edge is limited to the depth of the water at the edge. So it is always thicker towards the middle.

[dmayers94]

That's a good point about the salinity of the lake. As far as I know, the salinity is uniform so I don't think it's a major factor.

Thanks for the responses everyone! My takeaway from this is very useful: that it's a lot more complicated than I initially thought. I thought it would be safe to assume that the ice would be thickest at the center of the lake, but this isn't necessarily the case. I'll look at my ice thickness results with an open mind.

[52isntbigenough]

Such a big deal is made when great lakes like Michigan and Superior freeze completely over, it's only logical to assume the ice is at it's thinnest in the middle.