I call it the 'snowman theory' . Up here in wisconsin we build snowmen. When the weather warms, they start to melt. As they get smaller, they melt faster. It has nothing to do with global warming, rather it is there is less mass of snow to maintain the cold, so as it shrinks, it melts faster.
Yep, it's why I like large cubes in my drinks instead of crushed ice! As the ice mass gets smaller, it melts faster.