A 1. Trans-Himalayan.
B 2. Himalayan.
C. Plains3. North Western.
4. Submontane.
5. Central and South Eastern.
6. South Western.

Trans-Himalayan Climate.—Spití, Lahul, and Ladákh are outside the meteorological influences which affect the rest of the Indian Empire. The lofty ranges of the Himálaya interpose an almost insurmountable barrier between them and the clouds of the monsoon. The rainfall is extraordinarily small, and, considering the elevation of the inhabited parts, 10,000 to 14,000 feet, the snowfall there is not heavy. The air is intensely dry and clear, and the daily and seasonal range of temperature is extreme. Leh, the capital of Ladákh (11,500 feet), has an average rainfall (including snow) of about 3 inches. The mean temperature is 43° Fahr., varying from 19° in January to 64° in July. But these figures give no idea of the rigours of the severe but healthy climate. The daily range is from 25 to 30 degrees, or double what we are accustomed to in England. Once 17° below zero was recorded. In the rare dry clear atmosphere the power of the solar rays is extraordinary. "Rocks exposed to the sun may be too hot to lay the hand upon at the same time that it is freezing in the shade."

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Fig. 17. Average Barometric and Wind Chart for January.

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Fig. 18. Average Barometric and Wind Chart for July.

The Indian Zones—Meteorological factors.—The distribution of pressure in India, determined mainly by changes of temperature, and itself determining the direction of the winds and the character of the weather, is shown graphically in figures 17 and 18. The winter or north-east monsoon does not penetrate into the Panjáb, where light westernly and northernly winds prevail during the cold season. What rain is received is due to land storms originating beyond the western frontier. The branch of the summer or south-west monsoon which chiefly affects the Panjáb is that which blows up the Bay of Bengal. The rain-clouds striking the Eastern Himálaya are deflected to the west and forced up the Gangetic plain by south-westernly winds. The lower ranges of the Panjáb Himálaya receive in this way very heavy downpours. The rain extends into the plains, but exhausts itself and dies away pretty rapidly to the south and west. The Bombay branch of the monsoon mostly spends itself on the Gháts and in the Deccan. But a part of it penetrates from time to time to the south-east Panjáb, and, if it is sucked into the Bay current, the result is widespread rain.

Himalayan Zone.—The impressions which English people get of the climate of the Himálaya, or in Indian phrase "the Hills," are derived mainly from stations like Simla and Murree perched at a height of from 6500 to 7500 feet on the outer ranges. The data of meteorologists are mainly taken from the same localities. Places between 8000 and 10,000 feet in height and further from the plains enjoy a finer climate, being both cooler and drier in summer. But they are less accessible, and weakly persons would find the greater rarity of the air trying.

In the first fortnight of April the plains become disagreeably warm, and it is well to take European children to the Hills. The Panjáb Government moves to Simla in the first fortnight of May. By that time Simla is pretty warm in the middle of the day, but the nights are pleasant. The mean temperature of the 24 hours in May and June is 65° or 66°, the mean maximum and minimum being 78° and 59°. Thunderstorms with or without hail are not uncommon in April, May, and June. In a normal year the monsoon clouds drift up in the end of June, and the next three months are "the Rains." Usually it does not rain either all day or every day; but sometimes for weeks together Simla is smothered in a blanket of grey mist. Normally the rain comes in bursts with longer or shorter breaks between. About the third week of September the rains often cease quite suddenly, the end being usually proclaimed by a thunderstorm. Next morning one wakes to a new heaven and a new earth, a perfectly cloudless sky, and clean, crisp, cool air. This ideal weather lasts for the next three months. Even in December the days are made pleasant by bright sunshine, and the range of temperature is much less than in the plains. In the end of December or beginning of January the night thermometer often falls lower at Ambála and Ráwalpindí than at Simla and Murree. After Christmas the weather becomes broken, and in January and February falls of snow occur. It is a disagreeable time, and English residents are glad to descend to the plains. In March also the weather is often unsettled. The really heavy falls of snow occur at levels much higher than Simla. These remarks apply mutatis mutandis to Dharmsála, Dalhousie, and Murree. Owing to its position right under a lofty mountain wall Dharmsála is a far wetter place than Simla. Murree gets its monsoon later, and the summer rainfall is a good deal lighter. In winter it has more snow, being nearer the source of origin of the storms. Himalayan valleys at an elevation of 5000 feet, such as the Vale of Kashmír, have a pleasant climate. The mean temperature of Srínagar (5255 feet) varies from 33° in January to 75° in July, when it is unpleasantly hot, and Europeans often move to Gulmarg. Kashmír has a heavy snowfall even in the Jhelam valley. Below 4000 feet, especially in confined river valleys the Himalayan climate is often disagreeably hot and stuffy.