Ice would melt irrespective of it's position, provided certain conditions are met.

Those are:
1. A sufficiently high temperature is reached.
2. A sufficiently low pressure is reached.

At atmospheric pressure, the temperature at which ice melts is 0^oC. Since water is warmer than ice, and at a higher temperature than 0^oC, the ice absorbs heat energy from the water to melt.

Does this answer your question? :)

Re condition Number 2: Because water expands when it freezes, ice MELTS when compresssd. Another unusual property of water!

Unknown008, you're from Mauritius - you have never made a snowball, have you? You take a handful of snow, squeeze it tightly and, voilà, a sturdy ball of ice flakes. If it is really cold you can't do it because it too cold to get below the melting point by squeezing and so it stays a powder.

Yes, never seen or touched real snow in my life :(

I never thought about that... and thought that the behaviour was similar to that of liquids when they evaporate... nice, thanks! :)

I did some research, and yes, you're right.

I've only seen the phase diagram of carbon dioxide, and I looked for that of water.

Under a fixed temperature, ice would either melt or sublime if I understand the graph well.

EDIT: Forgot to add "as pressure decreases" to my last line.

http://upload.wikimedia.org/wikipedia/commons/thumb/3/34/Phase-diag2.svg/500px-Phase-diag2.svg.png

You are correct in your interpretation of the slope of the solid/liquid phase boundary (the dotted green line). I wonder what the solidgreen line is? Maybe it is the normal liquid behavior. I have never seen that before. Where did yhou get this graph?

No snow -- the drawback to living in a tropical paradise!
Next January, go to the beach while I am shoveling my driveway and sidewalks and you will know the pleasure of living in a tropical paradise!!

Lol, I got it from wikipedia, one of my favourite sources of information :)

I googled Phase Diagram Water and first came wikipedia.

Well, I'd be at sea in November... my first cruise. It's got an awesome promotion, so my mother is taking this opportunity.