Water
A steep density gradient in a body of water can have the effect of trapping energy and preventing convection, such a gradient is employed in solar ponds. In the case of salt water, sharp gradients can lead to stratification of different concentrations of salinity. This is called a Halocline.
Read more about this topic: Density Gradient
Famous quotes containing the word water:
“Oh, a friend! How true is that old saying, that the enjoyment of one is sweeter and more necessary than that of the elements of water and fire!”
—Michel de Montaigne (1533–1592)
“I am no Poet here; my pen ‘s the spout,
Where the rain water of my eyes run out,
In pity of that name, whose fate wee see
Thus copied out in griefs Hydrography:
The Muses are not Mer-maids, though upon
His death the Ocean might turn Helicon”
—John Cleveland (1613–1658)
“This sand seemed to us the connecting link between land and water. It was a kind of water on which you could walk, and you could see the ripple-marks on its surface, produced by the winds, precisely like those at the bottom of a brook or lake. We had read that Mussulmans are permitted by the Koran to perform their ablutions in sand when they cannot get water, a necessary indulgence in Arabia, and we now understand the propriety of this provision.”
—Henry David Thoreau (1817–1862)