It is these mild climates which we must now attempt to explain. This leads us to inquire what would happen to the climate of the earth as a whole if the conditions which now prevail at times of few sunspots were to become intensified. That they could become greatly intensified seems highly probable, for there is good reason to think that aside from the sunspot cycle the sun's atmosphere is in a disturbed condition. The prominences which sometimes shoot out hundreds of thousands of miles seem to be good evidence of this. Suppose that the sun's atmosphere should become very quiet. This would apparently mean that cyclonic storms would be much less numerous and less severe than during the present times of sunspot minima. The storms would also apparently follow paths in middle latitudes somewhat as they do now when sunspots are fewest. The first effect of such a condition, if we can judge from what happens at present, would be a rise in the general temperature of the earth, because less heat would be carried aloft by storms. Today, as is shown in _Earth and Sun_, a difference of perhaps 10 per cent in the average storminess during periods of sunspot maxima and minima is correlated with a difference of 3 deg.C. in the temperature at the earth's surface. This includes not only an actual lowering of 0.6 deg.C. at times of sunspot maxima, but the overcoming of the effect of increased insolation at such times, an effect which Abbot calculates as about 2.5 deg.C. If the storminess were to be reduced to one-half or one-quarter its present amount at sunspot minima, not only would the loss of heat by upward convection in storms be diminished, but the area covered by clouds would diminish so that the sun would have more chance to warm the lower air. Hence the average rise of temperature might amount to as much at 5 deg. or 10 deg.C.