• You are viewing the forum as a Guest, please login (you can use your Facebook, Twitter, Google or Microsoft account to login) or register using this link: Log in or Sign Up

Nocturnal temperatures

Fred Dulley said:
Ever been swimming at night? The water is slightly warmer at night than during the day because throughout the day the water has been absorbing solar radiation, which steadily warms it up.
Click to expand...

Actually it is right, the water is usually warmer at night. Well, I stand corrected. :)
 
Fred Dulley said:
Ever been swimming at night? The water is slightly warmer at night than during the day because throughout the day the water has been absorbing solar radiation, which steadily warms it up.
Click to expand...
By that same rational the temperature must decrease gradually throughout the night. Otherwise the water would just keep getting warmer and warmer. Surely the perceived differences if due to the atmospheric temp dropping and the water retaining its absorbed temp and releasing it slowly back into the atmosphere?

I must agree that the amount of water that we are talking about in the wilds (rivers/lakes) I wouldn't expect the temperature to vary massively overnight. Seasonally probably but overnight would possibly be a degree or two at best? I guess this would depend on where theses rivers/lakes are. During the summer in certain places in Asia, Africa, the Americas I bet there would be little difference in the outside temps night or day.
 
Careful there. Our perception of temperature may lead to inaccuracies. You could feel that the water is warmer just because air temperature is lower. The reverse is also true. If you keep your hands in ice for a couple of minutes then open the hot tap water, it feels like burning. After a while you'll see that temp was just fine.

check this: http://www.field-studies-council.org/fi ... .2_102.pdf

Althouh night temperatures in rock pools are influenced by the previous high tide you can see that temperature starts to decrease by the end of the evening in some of the these rockpools.

cheers

GM
 
(Not got time to follow the link, other than to see it's about rockpools, but ...)

Looking at this quantatively, how many degrees difference does the temperature of a large body of tropical water vary within a 24hr period, on average?
 
idris said:
Looking at this quantatively, how many degrees difference does the temperature of a large body of tropical water vary within a 24hr period, on average?
Click to expand...

Also those variants over different times of the year would be interesting too.
 
The only way to make any of this relevant would be to first decided on what fish or plants we are tying to please - fish from a fast flowing section of the Amazon or fish from a tiny shallow tributary in the Congo? The great rift valley lakes of Africa or a rice paddy in Thailand? :?
 
You must log in or register to reply here.
Back
Top