Mark_18: When the 'firmament' is renewed on the earth as it was in the beginning, we will have a planet-wide constant temperature. Just remember that in the earlier times, animals common to the sub tropics were found in what is now Siberia and Alaska... Mastodons with buttercups in their digestive tracts have been found frozen in the permafrost.
A nice detailed study on some aspects of these time lines can be found here:
http://www.christianityboard.com/ear...y-t79.html?amp;