Of course there will be variables. Here is what I can see some of the world's volcanos will have erupted and changed the continents shapes and climates. And when that happens it will cause Ice ages and warming periods which will further change the lands topography, new rivers, lakes, mountain ranges. Some features will sink, and others will rise. If Humanity is still here then most likely it will be a preindustrial type society for most of our knowledge will either be lost or unintelligible and we will not have the materials at hand to make many of the things that are necessary to proceed to the next step in a machines production process. There wont be enough resources to last 400 years of nuclear winter as what is the common term when the sun no longer can shine on much of the planet due to the ash and gasses that are put into the atmosphere from large volcanos.

That is just one possability.