Page:Africa by Élisée Reclus, Volume 4.djvu/133

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CLIMATE OF SOUTH AFRICA. 97 remarkable contrast in their respeitive temperatures. The Antarctic polar current setting from the south parses west of Capetown, and aitvr entering the Atlantic, continues to skirt the west coast beyond the Congo and Ogoway estuaries. On the opiK>8ite side the ^lozambique current, coming from the Indian Ocean, flows by the shores of Natal and Kafirland, penetrates into the southern inlet» of Cape Colony, and at last rounds the extreme continental headlands, whence its local name of the Agulhas Current. In summer, when the cold Antarctic stream is directed by the regular south winds more swiftly towards the north, its temperature is found to be from 50® to 52° F. But in False Bay, immediately east of the Cape, the water brought by the current from the Indian , Ocean is often as high as Gfi*^, rising in the neighbourhood of Cape Agulhas even to 78° or 80° F. In consequence of this great contrast in the character of the neighbouring marine waters, Capetown and Simon's Town, although 8(^])arated only by a narrow intervening promontory, have different climates. The latter lies nearer to the South I^ole, but nevertheless enjoys a warmer atmosphere by at least three degrees. The regular winds which prevail on the South African seaboard succeed each other in such a way as to diminish the contrasts between the seasons. Hence the average yearly variations from winter to summer are far less intense in Cape Colony than in the regions possessing a corresponding climate in the northern hemisphere. The cold south-east trade winds prevail chiefly in summer, thereby tempering its excessive heats. The returning bree/es — that is to say, the north- westerly aerial currents — set in, on the contrary, during the winter months, when the whole system of trade winds has been attracted northwards in the wake of the sun. All these normal currents, however, are frequently deflected towards the tablelands of the interior by the continental centres of heat. Thus on the eastern seaboard the trade wind veers at times quite round to the west, wherens in the north it sets southwards and in the Atlantic takes an easterly dirtetiun. In the hot season, when the winds blow from the north after traversing the desert inland plateaux, the atmosphere seems like the blast of a flery furnace, and at such times the heat is most oppressive, especially in the upland regions farthest removed from the moderating influence of the surrounding < eeanic waters. In general as we advance from the coast towards the interior, the climate acquires a more con- tinental or extreme character, becoming not only colder in winter, which might be exjjluined by the greater altitude of the land, but al^o muih warmer in summer.

  • Temperatures of various South African towns : —

South latitude. Al itude. Mean Temperature. Me«D ExtremM. Simon's Town . 34=' 12' 50 feet 63 ' F. 'jr and 43' Capettiwn . 33° 56' 40 „ 62" 91° „ 39°-8 Port Elizabeth . 33^ 57' 240 „ 62°-8 95° „ 42°-8 Graham's Town . 33° 20' 1.800 „ 62°- 4 102° „ 34° Graaf Roinet 3-2° 16' 2,.?60 „ 64°4 10r-2„ 33' Bloemfoutein 28"" 66' 4.550 „ 6P-8 93°-6„ 41° Du Toifs Pan 28° 46- 4.000 ,. 62°-6 104° „ 40°-5 Pretoria 25° 46- 4.300 „ 66^-8 95°-4 „ 3'2°o Port Durban 29° 50' 250 „ 67° n Pietar Maritzburg 29° 30' 2,100 „ 62°-7 96° „ 32°-4 104— AT