To add to that... When the ice caps recede they reveal more land and water surface. The sun uses these surfaces to heat the Earth much more so than the whiteness of ice and snow.
And then you have the effect of polution in the atmosphere that blocks out the sun. Then to counter that you have the greenhouse effect of the polution that traps the heat. It seems there are two sides to every factor. Which leaves people with agendas to use and stilt the facts....