Our long nightmare is finally over....

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Randy
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Joined: 05/05/2002 - 10:38
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Our long nightmare is finally over....

Lake Lanier Sunday Feb 23rd - 1071.4, Full Pool - 1071.  First time for many months the lake has been full Wink

It seems like it was not very long ago that the lake was around 1055.   Cray 2

Now, there's a new problem - water goes up to the "steps" at Van Pugh, and there is no wind for the first 20 feet or so.  Still, I hope they keep it like this.

Randy.

What happens in a black hole stays in a black hole.

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Re: Our long nightmare is finally over....

I'd be more excited if everytime it rained it was over 37 degrees.  I think the last 10 ft of Lanier has come at an average temperature of about 35. I exaggerate only slightly.

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Re: Our long nightmare is finally over....

Interesting point.  Do you think the cold water sinks to the bottom of the lake, or floats on the top?

Randy

What happens in a black hole stays in a black hole.

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Re: Our long nightmare is finally over....

Here is what I found on the Web about water temperature and density.  I seemed to remember from the school days many moons ago that at 4C water is the densest, the following confirms it.

"Temperature determines many physical characteristics of a water body during different seasons of the year. In the winter, water's temperature-dependent density allows aquatic life to survive. Ice is formed at 0 degrees Celsius. Thus, ice will remain at the top of the water body. Sun shining through the ice will serve to warm the water below slightly, keeping the temperature just above freezing. Water at 4 degrees C is the most dense, and will sink to the bottom and be replaced by lighter 1 - 3.9 degrees C water. The continual process of heating and sinking keeps the water body from freezing entirely (Smith, 1990)."

What that means is that we either get the cold stuff to fall into, or the extremely cold stuff, but not much in between.
Just think, it’s better than where I used to windsurf in Canada, there you would be hitting hard ice this time of year.

PS.
(in the next lecture we’ll explore the relationship between F and C Smile

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Re: Our long nightmare is finally over....

So the water that is about 39 degrees sinks to lowest level of the lake.  Seems like this would be below the level we are sailing at.  In fact, most of the time, it seems like the reported water surface temp never goes below about 45 degrees, though I am not sure how they measure it.  (One of my friends stuck a thermometer in the lake one time and read 38 degrees in the winter. It was reported in the 40's at the time.)

Now I am wondering if the water at the bottom of the lake stays cool all year round. i.e. if you went down 50 ft, would the water in the summer be a lot colder?  I'm guessing it would be colder, but I don't know how much.  (Seems like in the summer it never gets much above 80, but I don't check it very often at that time of year.) Any scuba divers out there?

Randy

What happens in a black hole stays in a black hole.

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Re: Our long nightmare is finally over....

We often dive for golf balls around the islands course and yes the further you go down the colder it is.  Weird thing is sometimes you hit a cold pocket of water and then a warm one at the same level, even at the surface.  

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