How cold is the water at the ocean floor?

The whole ocean averages 38 F. Th deep is about 32F to 35F.

I'm not an expert, but I know there are some parts of the ocean floor where hydrothermal vents exist which actually make the floor very very hot. They're literally openings in the earth's crusts where water meets lava. The water instantly boils and vaporizes on contact, spewing sufuric gases and making for extreme ecological environments. So it's not allll cold, is what I'm saying. http://en.wikipedia.org/wiki/Hydrothermal_vent I think they have little pressurized submarines called "Alvin" to study the extreme depths of the ocean, which probably protect them from the intense water pressure and temperature? Alvin was what they used to explore the wreck of the Titanic. http://en.wikipedia.org/wiki/ALVIN

Sorry, no references, just common knowledge. You might check an online encyclopedia for a reference. The water at the ocean floor is at 4 degrees celsius. Water reaches its greatest density at this temp. As it gets colder it will begin to rise; at zero celsius it will freeze, and we all know ice floats! (If water continued to increase in density as it cooled past 4 degrees, the oceans would freeze from the bottom up, and never thaw! One of the many unique characteristics of water!)

Now i could be wrong about this but i'm sure at a certain depth the water can get very cold but at the very bottom i think it should start getting hot since that's how volcano's and land masses are usually formed from the bottom of the sea.

In the Artic, under the ice it can go a few degrees below 32 and still be liquid. The pressure and constant movement enables this.

http://www.physlink.com/Education/AskExperts/ae666.cfm

very very. i used to be a professional scuba diver.

its freezing, meaning 0 to -2 degrees C or 32 degrees F but the enormous pressure at the ocean floor prevents it from freezing. or in other words: AT sufficient ocean depths (several km) there is an increase of temperature with depth corresponding to the adiabatic lapse rate 10-6 °C/cm. Toward the bottom, the gradient becomes increasingly superadiabatic, because the water is heated from below by a geothermal heat flux H. Because H is small (10-6 calories cm-2 s-1), only a slight superadiabatic effect is expected: |dT/dz| < 2 at elevation z > 1 m. Measurements of hyperadiabatic gradients (|dT/dz| = 10−1,000 ) several metres, or even tens of metres, above the bottom have been reported1−4, though it seems inconceivable that a strongly unstable layer several metres thick can persist. The experiment described here indicates that |dT/dz| = 1.3 at z 1 m.

its really not explored as much as people might think, we probably know more about our solar system than we do about the sea floor