Pressure melting point

The pressure melting point of ice is the temperature at which ice melts at a given pressure. The pressure melting point is nearly a constant 0 °C at pressures above the triple point at 611.7 Pa—where ice, water, and water vapour coexist in equilibrium—through atmospheric pressure (100 kPa) until about 10 MPa. With increasing pressure above 10 MPa, the pressure melting point decreases to a minimum of −21.9 °C at 209.9 MPa. Thereafter, the pressure melting point rises rapidly with pressure, passing back through 0 °C at 632.4 MPa.