This aerial photograph of trade wind clouds is taken near the west coast of Africa heading towards the Canary Islands. Such clouds are characteristic for the subtropical calms. In these so called horse latitudes the vertical motion of the air is towards the surface because of the global atmospheric circulation. The result is the high pressure belt causing everlasting sunshine. This is the reason for the development of the arid zone and hence the dry climate of the Canary Islands.
Pentax MZ5, Sigma 70-300mm, f/5.6, 1/1000sec, Kodak Ektachrome E6, ISO 100