Bottoms up...pond inversions

[spider solo]

At 1st I thought it was science fiction but...

Apparently sometime in the spring, presumbly around this time, water in a pond will "flip" it's self over.
Either the water on top sinks down or the other way around... the pond goes "Bottoms Up" .

Anybody out there have some more info on the subject?

Paddling around I would certainly be clueless as to what phase a pond might be in.
Are there clues?
Is this common knowledge among people who go fishing..?

I would think there are whole life cycles based on this phenomenon.
Perhaps it is natures way of oxygenating itself ?

 

[Rick]

I thought it was in the stifling heat of August that ponds have temperature inversions and the water flips, sometimes causing fish kills and Algae blooms. Seems like I recall them happening a few times on some of the smaller Finger Lakes (NY). I didn't know it happened in spring, though.
I thought it was the upper layers of water got too warm and the colder waters from below came up, though. I'd be interested to know more, though.

 

[spider solo]

??

Nessmuk posted a great explanation which I read last night.
This morning I don't see it ?
I stll have the text from it.
I can retype it for if need be...

I had never heard of it happening in the warm/hot summer days so perhaps it happens more than I had heard of,or for various reasons resulting in the same effect.

 

[el-bagr]

Water is densest at a temperature of 39.2 F. Water that is any warmer or colder is less dense. Because of this density differential, lakes and ponds tend to stratify, with water closest to 39.2 F sinking to the bottom.

At the moment of ice-out, under ideal conditions, the surface water is 32 F. As that surface layer warms toward 39.2 F, it gets more dense, and starts to sink. This causes the spring turnover, which tends to mix the water. (One effect is to eliminate or mitigate oxygen deprivation in the depths.)

The more impressive turnover happens in fall, as the surface waters become cooler than -- and denser than -- the waters below.

Yes, it's a fishing thing. For one, ice-out and turnover will bring the salmon to the topwaters, where you don't need to get your fly down 30' to target them.

One book that covers this subject, and much more, is Ice: The Nature, the History, and the Uses of an Astonishing Substance by Mariana Gosnell. I highly recommend this book. It's along the lines of Snow by Ruth Kirk, but I especially liked Gosnell's writing style -- and New England focus.

 

[spider solo]

thanks... I'll look for the book(s)
I've had a rough idea of the subject from a few years ago, but this year I got to thinking what might be a big mystery to me might be common knowledge to others ,so thought I would ask.
I"ll look forward to reading up on it...

 

[bubba]

Interesting explaination, El-bagr. I didn't know that this happened in the spring, but was aware of a flip in summer. This happens on lakes as large as the Great Lakes!!

 

[DSettahr]

Different lakes turn over at different rates. In temperate regions, most lakes turn over twice a year. As you move from temperate to arctic or tropical regions, you start to see lakes that turn over only once a year, and finally lakes that never turn over. Other factors besides temperature can influence how often a lake turns over, especially wind.

Tropical lakes that never turn over, especially deep ones, can be very dangerous. At the bottom of these lakes, carbon dioxide builds up due to the pressure and the cold temperature of the water. When the lake finally does turn over, most often due to a earthquake, this gas is suddenly released with devastating effects. This is what happened to Lake Nyos in Africa, resulting in the death of more than 1700 people.

 

[DSettahr]

Interesting explaination, El-bagr. I didn't know that this happened in the spring, but was aware of a flip in summer. This happens on lakes as large as the Great Lakes!!

Most lakes usually flip during ice-out in the spring, and again in the fall. During the summer, the lakes are very well stratified and stable. It isn't until the fall, when the upper layers begin to cool down, that the turn over occurs.

 

[spider solo]

Pow Wow Pond ..fish...dead

I pick up the newspaper (Manchester Union Leader thurs May 1 2008) and the front page is about all the dead fish that just washed ashore in the small pond where I live.
Thats the Pow Wow Pond in NH .....I've already been in there paddling at least three times this year and eveything looked fine.
They say it might be that it was lowered to much last year in an attempt to stop weeds and that the fish suffocated...ran out of oxygen.
But
Ice has been out for a long time here..
I know that ponds will "invert" from time to time.
Though I don't think it would "burb "up a bunch of already dead fish...?

Any ideas/info ?

(maybe some one can put a link for the article)