If you imply that Greenland was "greener" during the viking era, which is what you do if you criticize someone for thinking that Greenland being filled with ice is "normal", you should learn some basic facts about how Greenland got its name first.

Greenland was discovered by the Icelandic (or Norwegian which was the same in those days)viking Erik Röde (or "Erik the Red"). There are actually two sagas written about his discovery: The Greenland Saga and Erik Röde's saga, and it is directly said in those that two things factored into the naming of Greenland; the green fjords (or rivers), where the water seemed brilliantly green in contrast to the land, and, and here I quote (pardon my free form translation) "He gave the land a name and called it Greenland, and said that it would encourage people to travel there, when the land had such a good name". (from Islendingabok)