When a lake is really a pond......
I caused some amusement when at my Minnesota (MN) residence I have looked out my window and said 'Look at that lovely view of the lake- what is its name?'.....'?it has no name...its a pond'
So, to up the educational nature of the blog (the brother recently classed my blog on some statcounter- as 'entertainment'in content- I feel the need to reform....) we ponder.....what defines a lake in the USA? and if the MN number plate says state of 10,000 lakes ...is that the true magnitude of the 'bodies of water' in this great state.
So first here is a map of the county section of Minnesota I am in (Washington county, town Mahtomedi- close to St Paul and Minneapolis) . Australian readers what seems remarkable? Gosh....there is a lot of water. Points for those who find my favourite....Lake Elmo (I am sure that the little red monster will be there on a pontoon if I go and visit).
The picture below of Grant and Sarah at Mahtomedi Beach- is on the shores of White Bear Lake.
So what defines a lake? well there is controversy. In MN they often use the classification of greater than 10 acres. If you use this classification then MN has 11,842 lakes. But others say...
a "lake is not classified by size or depth as some may suggest." In fact, a lake may be defined as an enclosed basin filled or partly filled with water. In general, a lake is an "area of open, relatively deep water that is large enough to produce a wave-swept shore."
Needless to say the body of water I can see right now from the Ericson's window is neither >10 acres in size and certainly does not produce a wave- swept shore and therefore = a POND.
This strikes me as an interesting geographical and cultural difference to Australia (especially Western Australia)...where there is a great lack of water (apart from the Indian Ocean!! that is....)). I will continue to think of those BIG ponds as Lakes....and believe many PONDS in Western Australia are deep down really lakes....because with the Wind in WA in many times of the year- we can always produce a wave swept shore.....
posted by Janine @ 10:22 AM
7 Comments:
just to be difficult and provide some more thought on Lakes, ponds and Australia - how does Lake Eyre in Aust fit the definition of a Lake when it only has water in it about every ten years???
Doesn't it get water in it almost every year, just not much??
Where do they do the landspeed records?
siobhan? Anyone? Lake Eyre facts?
drat I tried for educational and now there are hard questions.....
okay - I did a quick browse on my new super fast "d-slam" link that we have just installed at home - result pasted below:
from -
http://www.environment.sa.gov.au/parks/lakeeyre/about.html
Lake Eyre National Park covers an area of 1,349,251 ha. Water from its three-State catchment area covers the lake about once every eight years on average. It has filled, or had water in it a number of times in the twentieth century, including 1956, 1971, 1974, 1976, 1989 and 1997. Lake Eyre has filled to capacity only three times in the past 150 years. The most extensive flooding occurred in 1974 when the lake filled to capacity with up to 34 cubic kilometres of water.
Ok...
I'll look up a little because I believe birds migrate there every year in a window of only three weeks or so. But I'll get back to you all :)
Alright, this makes a bit more sense to me... I was wondering if it only has water every few years how the birds migrate there, if not annual. It would seem this is one of the great mysteries of bird migration!
"Lake Eyre floods only once in every few years - after big rains in Queensland. About 60 species of birds respond to its call - and six to eight million waterbirds make the pilgrimage. Some travel a thousand kilometers or more."
"No one knows how the birds know that the salt lake, Lake Eyre, has been flooded or how they know the way there or to the other usually temporary inland lakes and waterways including Cooper Creek and Coongie Lakes."
http://www.diamantina-tour.com.au/maps/lake_eyre_detail%20copy.jpg
Gives a good indication of size (approx 100 by 150 kms)
wow, see what happens when you put in educational content....we all learn something! Well done team!
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