ABSTRACT
Knowledge of the influence of upper air conditions upon the climate of India has greatly increased and though much more knowledge is required it is possible to weave together a description of the seasons and their variations from year to year. The classification of climates from the point of view of human comfort and efficiency has many formidable obstacles to overcome. The cool season weather and climate are dominated by locally subsident air: the Himalayan barrier protects the sub-continent from the true winter monsoon blowing from Siberia across China, and it may be considered as part of the seasonally quasi-permanent. The general pattern is towards the reestablishment in the north of the cool season, towards the return of the westerlies and the westerly jet south of the Himalayas, interacting with subsident air at the surface. Meantime the northern mountains and especially the Himalayas receive considerable amounts of precipitation, largely in the form of snow.
