I read all of that and apart from this part "until they saw...

I read all of that and apart from this part "until they saw Greenland, and the mountains below the joklers" found virtually no descriptions of Greenland except documenting being there. They were so confused intitially that they could have been almost anywhere? What are jocklers? Could they be massive ice sheets higher than the coastal mountains?

Then this part to really confuse the theory.

"They asked if Bjarne thought that this was Greenland, but he said that he as little believed this to be Greenland as the other; "because in Greenland are said to be very high ice hills." They soon approached the land, and saw that it was a flat land covered with wood. Then the fair wind fell, and the sailors said that it seemed to them most advisable to land there; but Bjarne was unwilling to do so. They pretended that they were in want of both wood and water. "Ye have no want of either of the two," said Bjarne; for this, however, he met with some reproaches from the sailors. He bade them make sail, and so was done; they turned the prow from the land, and, sailing out into the open sea for three days, with a southwest wind, saw then the third land; and this land was high, and covered with mountains and ice-hills."

I accept it was a warm period and people lived there for while but as for the ice I haven't seen anything to suggest it had changed let alone gone.