Page:Physical Geography of the Sea and its Meteorology.djvu/220

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PHYSICAL GEOGRAPHY OF THE SEA, AND ITS METEOROLOGY.

rainless regions of Lower California reminding one of Africa, with its deserts between the same parallels, etc. Moreover, the North Pacific, like the North Atlantic, is enveloped, where these warm waters go, with mists and fogs, and streaked with lightning. The Aleutian Islands are almost as renowned for fogs and mists as are the Grand Banks of Newfoundland. A surface current flows north from Behring's Strait into the Arctic Sea: but in the Atlantic the current is from, not into the Arctic Sea: it flows south on the surface, north below; Behring's Strait being too shallow to admit of mighty under currents, or to permit the introduction from the polar basin of any large icebergs into the Pacific. Behring's Strait, in geographical position, answers to Davis' Strait in the Atlantic; and Alaska, with its Aleutian chain of islands, to Greenland. But instead of there being to the east of Alaska, as there is to the east of Greenland, an escape into the polar basin for these warm waters of the Pacific, a shore-line intervenes: being cooled here, and having their specific gravity changed, they are turned down through a sort of North Sea along the western coast of the continent toward Mexico. They appear here as a cold current. The effect of this body of cold water upon the littoral climate of California is very marked. Being cool, it gives freshness and strength to the sea breeze of that coast in summer-time, when the "cooling sea breeze" is most grateful. These contrasts show the principal points of resemblance and of contrast between the currents and aqueous circulation in the two oceans. The ice-bearing currents of the North Atlantic are not repeated as to volume in the North Pacific, for there is no nursery for icebergs like the frozen ocean and its Atlantean arms. The seas of Okotsk and Kamtschatka alone, and not the frozen seas of the Arctic, cradle the icebergs for the North Pacific.

392. The Lagulhas Current and the storms of the Cape.—The Lagulhas current, as the Mozambique is sometimes called, skirts the coast of Natal as our Gulf Stream does the coast of Georgia, where it gives rise to the most grand and terrible displays of thunder and lightning that are anywhere else to be witnessed. Missionaries thence report to me the occurrence there of thunder-storms in which for hours consecutively they have seen an uninterrupted blaze of lightning, and heard a continuous peal of thunder. Reaching the Lagulhas banks, the current spreads itself out there in the midst of cooler waters,