An increase in the lands would cause changes in several climatic conditions. (a) The range of temperature between day and night and between summer and winter would increase, for lands become warmer by day and in summer than do oceans, and cooler at night and in winter. The higher summer temperature when the lands are widespread is due chiefly to the fact that the land, if not snow-covered, absorbs more of the sun's radiant energy than does the ocean, for its reflecting power is low. The lower winter temperature when lands are widespread occurs not only because they cool off rapidly but because the reduced oceans cannot give them so much heat. Moreover, the larger the land, the more generally do the winds blow outward from it in winter and thus prevent the ocean heat from being carried inland. So long as the ocean is not frozen in high latitudes, it is generally the chief source of heat in winter, for the nights are several months long near the poles, and even when the sun does shine its angle is so low that reflection from the snow is very great. Furthermore, although on the average there is more reflection from water than from land, the opposite is true in high latitudes in winter when the land is snow-covered while the ocean is relatively dark and is roughened by the waves. Another factor in causing large lands to have extremely low temperature in winter is the fact that in proportion to their size they are less protected by fog and cloud than are smaller areas. The belt of cloud and fog which is usually formed when the wind blows from the ocean to the relatively cold land is restricted to the coastal zone. Thus the larger the land, the smaller the fraction in which loss of heat by radiation is reduced by clouds and fogs. Hence an increase in the land area is accompanied by an increase in the contrasts in temperature between land and water. (b) The contrasts in temperature thus produced must cause similar contrasts in atmospheric pressure, and hence stronger barometric gradients. (c) The strong gradients would mean strong winds, flowing from land to sea or from sea to land. (d) Local convection would also be strengthened in harmony with the expansion of the lands, for the more rapid heating of land than of water favors active convection.