HELLO! They are using ice which would melt due to climate change causing oceans to rise and moving to thirsty people in the desert thus preventing the ocean levels from rising! A Win-Win.
The people drinking the ice eventually pee most it in the ocean....it evaporates and is carried around...some of it gets refrozen into ice at higher altitudes....just think of all the carbon sequestration which will occur when Greenland starts growing plants. And all tundra areas start growing trees.