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when does a pond become a lake and a lake become a sea etc

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did you know....
98615.  Mon Oct 02, 2006 2:24 pm Reply with quote

when does a pond become a lake and a lake become a sea and a sea become a ocean?

 
smiley_face
98618.  Mon Oct 02, 2006 2:48 pm Reply with quote

The difference between a pond and a lake is entirely subjective, although there are some sources which seem to state that a pond is less than 10 acres in area. Others say that a pond is different to a lake in that light can penetrate to the bottom even in the deepest parts of the lake.

A lake differs from a sea in that it is usually fresh water, lacks a current, and is surrounded by land.

A sea tends to be smaller than an ocean, and is a part of the ocean. Both seas and oceans are saltwater, but I think it is an ocean when it separates two continents (well, I think thats accurate, but there are probably many counter examples).

Hope that helps a bit.

 
grizzly
98621.  Mon Oct 02, 2006 3:05 pm Reply with quote

The fresh water/salt water division is not an accurate one to use. Since many lakes can be more salty than the sea (these mainly occur in hot/dry climates where the water evapourates leaving behind the solutes). The Caspian Sea for example (which is a lake, the largest in the world) is a salt water lake.

The most accurate division between a lake and a sea is that a sea will be open to the ocean and hence at "sea level". Lakes on the other hand will have no outlet to the sea and consequently can be above or below sea level (the Dead Sea, another lake, being an example of a lake below sea level).

The difference between a pond and a lake are as Smiley_Face points out, purely subjective.

 
Jumper
98627.  Mon Oct 02, 2006 3:14 pm Reply with quote

It all depends on how far the ripples go when you throw a pebble into it...

 
djgordy
98631.  Mon Oct 02, 2006 3:32 pm Reply with quote

grizzly wrote:
The Caspian Sea for example (which is a lake, the largest in the world) is a salt water lake.


This is a matter of dispute. Some people define the word "lake" as a body of water surrounded by a land and thus say that the Caspian Sea is therefore a lake. However, some people say that the fact that it is salt water means that it really is a sea.

Although this seems, on the face of it, to be merely a matter of nomenclature, with the same import as whether Pluto is a planet or not, there are other implications.

Quote:
Is the Caspian a sea or a lake? The point is that fishing, mineral and oil rights differ according to the word used. There has been a long dispute about this among the riperian states. From Thailand, Steve Torok writes: The question is still unresolved. It refers to the applicability of the UN Law of the Sea with its freedom of navigation stipulation beyond 12 nautical miles but exclusive economic zones out to 200 nautical miles from shore. If the Law of the Sea is not applicable, any agreed division by riparian states is possible. Even if it is applicable, agreement by riparian states can override it: see recent East Timor Sea agreement between Australia and Timor, allowing for hydrocarbon exploration and exploitation at favorable terms to both. RH: Perhaps Cameron Sawyer knows the terms of the agreement among the riperian states of the Caspian Sea/Lake.


http://cgi.stanford.edu/group/wais/cgi-bin/index.php?p=308

 
grizzly
98634.  Mon Oct 02, 2006 3:46 pm Reply with quote

Now that is QI djgordy.

I'm inclined to say the salt water definition doesn't work because that would mean that a sea could become a lake and vice versa (since lakes can through the processes of dessication or flooding see a radical change in the salinity of the water, as has happened with the Aral Sea).

 
did you know....
98638.  Mon Oct 02, 2006 4:04 pm Reply with quote

another good question is what was the best thing before sliced bread? i think the bread slicer. any ideas?

 
grizzly
98639.  Mon Oct 02, 2006 4:10 pm Reply with quote

Since the first commercially available sliced bread loafs appeared in 1928, anything invented before 1928 could count as best thing before sliced bread. Then again perhaps you could judge the best thing to go out of use before sliced bread was invented (I think non-sliced bread would be a good contender for that one).

 
did you know....
98640.  Mon Oct 02, 2006 4:12 pm Reply with quote

the wheel wasnt a bad idea was it?

 
djgordy
98642.  Mon Oct 02, 2006 4:15 pm Reply with quote

Seas and lakes can, and do flip from one to the other.

It is believed that the area now covered by the Black Sea was, or at least contained, a freshwater lake until about 5,600, at which time the rising level of sea waters due to the end of the last ice age, caused the Mediterranean to flood over the Bosphorous.

Some people believe this to have been the origin of the stories of a great flood to be found in the Bible and the Sumerian Gilgamesh myth (and possibly also the story of Atlantis). It ought to be pointed out, though, that there was a gap of at least 3,000 between the inundation of the Black Sea and the emergence of the Gilgamesh mythos so this remains speculative.

http://gsa.confex.com/gsa/2003AM/finalprogram/session_9644.htm

 
grizzly
98646.  Mon Oct 02, 2006 4:19 pm Reply with quote

Well yes I would accept that classifications would need to be flexible over geological and climatological time scales. However, you can't have a sea being reclassified as lake every year if it were to be flooded with fresh water every wet season (and become a sea when salinity increases during dry months).

 
mckeonj
98663.  Mon Oct 02, 2006 4:52 pm Reply with quote

did you know.... wrote:
another good question is what was the best thing before sliced bread? i think the bread slicer. any ideas?

Quite definitely custard powder.

 
The Luggage
98735.  Tue Oct 03, 2006 3:41 am Reply with quote

Custard powder will always be the best thing.

 
Tas
98752.  Tue Oct 03, 2006 4:32 am Reply with quote

Quote:
the wheel wasnt a bad idea was it?


I'm not so sure....it is one of the major components for industrialisation. Look what that has enabled us to do to the environment!

:-)

Tas

 
Paddy Boy
100436.  Sat Oct 07, 2006 4:32 pm Reply with quote

a sea has sharks a lake dont (not counting bull sharks)

 

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