Question

Why does it become very cold when ice starts melting in cold countries?

Answer 1

Melting ice absorbs a large amount of heat from the surroundings without any rise in temperature. This heat is the latent heat of fusion of ice, which is 336 J g⁻¹ (or 336000 J kg⁻¹). When ice or snow starts melting, it takes this heat from the surrounding air, so the air loses heat and becomes bitterly cold.