FOOTNOTES:
[1] “Notes on the Geological Formation of Portions of German South-West Africa”—South African Journal of Science, June, 1911.
[2] Moffat’s “Missionary Labours and Scenes in South Africa,” p. 76.
[3] Report of Director of Irrigation for period 1st January, 1912, to March, 1913.—Cape Times, Ltd., Cape Town.
Chapter II
CLIMATE AND RAINFALL
From what has been said about the diversity of the physical conditions of the country it will be readily inferred that there is a considerable variation of climate. When it is remembered, too, that the land lies within the tropic of Capricorn and corresponds in latitude to the central provinces of India, between Bombay and Calcutta, the reader will be prepared to learn that it is excessively hot in the summer months and very unhealthy. As a matter of fact the climate as a whole is healthy and the heat much less trying than the traveller from India expects to find in such a latitude. Various factors account for this, as we shall see.
There are two seasons, summer and winter; summer lasts from October to April, and winter from April to September.
The heat is sometimes great on the coast, some little distance from the sea, where the sea mists do not reach, rising occasionally to 120° F. in the shade. But at noon the fresh south-west wind blows strongly from the sea, and the nights are comparatively cool and refreshing. The sudden fall of temperature at sunset is often a source of danger to those who have not learned to guard themselves against rapid variations of temperature. Strangely enough, the hottest day in the year may be a day in the middle of winter, for it is in the winter that a fierce, hot, desert wind from the east comes sweeping across the country, sending up the thermometer with a rush. The winter may thus have the hottest, as well as the coldest, days of the year. A comparison of the temperatures of the principal centres of the country with Kenhardt and Kimberley, two of the hottest districts in the Cape Province, may not be without interest:
| November. | February. | July. | |
|---|---|---|---|
| Windhoek | 86 | 82 | 68 |
| Swakopmund | 58 | 62 | 55 |
| Walvis Bay | 60 | 64 | 57 |
| Luderitzbucht | 62 | 68 | 55 |
| Omaruru | 82 | 82 | 62 |
| Rehoboth | 86 | 86 | 60 |
| Kenhardt | 74 | 85 | 57 |
| Kimberley | 78 | 82 | 55 |
The feature of the coast climate is the heavy fogs occasioned by the proximity of the cold waters of the Benguella current to a heated interior, and the contact of the cool south-west winds with the north-west air currents. These fogs veil the seaboard in a thick haze during the night and often last to noon; they supply, however, a considerable amount of moisture to the coast border of the Namib, since they are sometimes so heavy that in a single night the sand is moistened to a depth of one or two inches, and the water flows down the stems of shrubs into the ground to a depth of six inches. Heavy rain occurs at very rare intervals. These conditions suggest that quite a useful supply of water might be obtained by the construction of dew-ponds, or mist-ponds, as they are now known to be, of which particulars are given by Mr. E. A. Martin in his recent work, entitled, “Dew-ponds: History, Observation and Experiment.” A whole year may pass without a single shower. Walvis Bay has an annual average rainfall of less than one inch. At such centres as Luderitzbucht, Swakopmund, and Walvis Bay, water for drinking purposes is condensed from the sea. Before the condensing plant was erected water had to be brought all the way up from Cape Town.
In the north and north-east the climate is almost tropical, but on the central plateau it is temperate, with great fluctuations of temperature during the day. The great heat of the sun during the summer months would make it rather trying for Europeans, were it not for the altitude and the great dryness of the air. As we have shown, the plateau is from 3,000 to 5,000 feet above sea level, and this is a factor of considerable importance in determining climatic conditions. The climate resembles parts of Rhodesia, and while there are hot days in the summer, for the most part the air is fresh, clear, and like elixir.
Great Namaqualand has a very warm summer; the shade temperature of the Orange River valley is often 110° F., while on the plains great fluctuations in the day temperature prevail. In the winter severe frosts and snow may be experienced, and snow may be seen on the Karas Mountains. There are also occasional frosts in the Windhoek region in this cold season.