In a star in the process of forming, contraction under gravitational pressure causes temperature to rise — but it's not the pressure, it's the contraction. (hubpages.com)
There isn't an impression of gravitational pressure, applied or released. (digitaltrends.com)
Google any reference, the water column 2000 - 10000 has temperature 0 - 3 C. Huge gravitational pressure keeps water close to temp of minimum volume (max density) i.e. for seawater, zero. (wattsupwiththat.com)