Why is it the air temperature outside is colder than the temperature water turns to ice but the ice on the sidewalk melts?

Ice can melt on the sidewalk even when the air temperature is colder than the freezing point of water due to several factors. One reason is that heat can transfer from the ground or other surfaces to the ice, providing enough energy to cause melting. Additionally, factors such as sunlight, wind, and the presence of salt or other substances can lower the freezing point of water or increase heat absorption, facilitating the melting process despite the air temperature being below freezing.