Thank you very much, i was looking for this comment. The issue with 1°, 1.5°, 2° C of warming is that at some point you will break a critical level where the process is greatly accelerated because less/no sunlight is reflected by the ice caps, further increasing the energy absorption. This is especially apparent in Greenland and the Alps (and probably other glaciers), where the uncovered earth now absorbs WAY more light than the sheets of ice did, thus essentially making the melting process irreversible (at least in our comprehension).