Small islands often leave downstream wakes consisting of swirling wind patterns, which distort the pattern of low clouds over the surrounding ocean. In this picture of Guadalupe Island off the Pacific coast of Mexico, the wind is blowing from the northwest (upper left toward lower right). The two largest vortices are approximately 15 miles apart. The rain areas over the tropical Pacific leave a similar wake more than 100 times as large, which distort the winds aloft. When the rain areas are rearranged by El Niño, the shape of the wind pattern changes, as indicated here. (Satellite image from NASA.)

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