Theories are not accepted as fact because new information or technology can show that the theory is incomplete or incorrect. A law is accepted as fact because it is a statement of what will happen and no exceptions have ever been found.

this is a good question! i'll do some research and come back when i have the answer!

the answer is false. this is because for ice to melt, it requires latent heat of melting. latent heat means heat energy required to change phase without any increase in temperatures. therefore, the ice will take energy from the environment to melt hence atmospheric temperatures will reduce.