Weather as it affects glaciation is a subject which has been under observation during the past century. Remnants of the last glaciation still exist in Greenland, Antarctica, and on some of the islands of the polar regions and in the high mountain fastenesses of the temperate and tropical zones. Weather conditions are modifying these ice-masses; in fact, the variability of the weather causes glaciers to grow at certain times and wane during other periods. The changes that are going on today are apparently similar to those that took place during past ages.
There is a distinction between weather and climate. Climate is the average of normal conditions of the atmosphere, while weather constitutes the variations from the normal. Weather changes are of a day-to-day occurrence. When averaged for the year and for longer periods, they yield differences which make the weather of one year vary from that of another, . . .