I understand that water is the most thick at 4 degrees celsius. That"s why water in ~ the bottom of a sea has actually that temperature. However how walk it get that temperatur in the very first place and why go the energy not distribute chin in such a means that the temperature is the same throught? Is it the corpuscle that have actually a temperature of 4 levels that sinks to the bottom or is that the pressure at the bottom that provides the water an ext dense?What if a sea is surrounding by constant weather problem and continuous atmospheric temperature. How would the temperature distribution look like as a duty of altitude under water? If the surrounding temperature is 20 degrees, would certainly the water in ~ the bottom if that is deep enought still it is in 4 degrees?
The factor water is denser at 4°C is because of the particular method molecules room disposed through respect to various other at that temperature.Molecular disposition of ice cream (voids space present):

<...> once cooled native room temperature fluid water becomes progressively dense, just like other substances, but at about 4 °C (39 °F), pure water get its preferably density. As it is cooled further, it broadens to end up being less dense. This unusual an adverse thermal expansion is attributed to strong, orientation-dependent, intermolecular interactions and is additionally observed in molten silica.

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<21>The solid type of most substances is denser 보다 the fluid phase; thus, a block of many solids will certainly sink in the liquid. However, a block of ice cream floats in liquid water due to the fact that ice is less dense. Upon freezing, the thickness of water decreases by about 9%.<22> This is as result of the "cooling" the intermolecular vibrations enabling the molecule to kind steady hydrogen bonds through their neighbors and thereby slowly locking right into positions storage of the hexagonal packing accomplished upon freezing to ice Ih. Whereas the hydrogen binding are shorter in the crystal than in the liquid, this locking effect reduces the average coordination variety of molecules as the liquid viewpoints nucleation. Other substances that broaden on freezing space acetic acid, silicon, gallium, germanium, antimony, bismuth, plutonium and likewise chemical link that type spacious crystal lattices v tetrahedral coordination.<...>In cold countries, once the temperature of new water get 4 °C, the great of water near the optimal in call with cold air continue to lose warm energy and their temperature falls listed below 4 °C. ~ above cooling below 4 °C, this layers do not sink together fresh water has actually a maximum thickness at 4 °C. Due to this, the layer of water at 4 °C stays at the bottom and above this class of water chillier than 4 °C space formed. Together water in ~ 0 °C is the least thick it floats ~ above the top and turns right into ice together the water proceeds to cool. Ice cream growth proceeds on the bottom the the ice cream as warmth is drawn away through the ice cream (the heat conductivity of ice is comparable to glass). All the while the water more down listed below the ice is still 4 °C. Together the ice layer shields the lake from the result of the wind, water in the lake will certainly no longer turn over. Return both water and ice room relatively great conductors of heat, a thick layer that ice and a thick layer of stratified water under the ice slow down more heat loss native the lake loved one to when the lake to be exposed. The is, therefore, unlikely that sufficiently deep lakes will freeze completely, uneven stirred by solid currents the mix cooler and also warmer water and accelerate the cooling. Thus, as long as the pond or lake does no freeze up completely, aquatic creatures space not exposed to freezing temperatures. In warming weather, chunks of ice cream float, rather than sink come the bottom whereby they could melt incredibly slowly. This properties therefore enable aquatic life in the lake come survive throughout the winter.

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Heat walk from hot to cold, no issue what, till equilibrium is reached. Therefore in theory, in a constant environment, given enough time, water - or any kind of other substance - will certainly reach a uniform temperature.But the s is much from being surrounded by a uniform temperature (top and also bottom) and also there are numerous currents adding variables to the mix.