Eastern Pacific High Sea

Off northern Chile, the Pacific meets the Atacama, a desert plateau stretching roughly 1,600 kilometres west of the Andes. The cold northward flow of the Humboldt Current cools marine air, producing cloud and fog more readily than rain. The Andes and the coastal range form a two-sided rain shadow, while the South Pacific anticyclone reinforces atmospheric stability. Much of the desert receives only about 15 millimetres of rain a year, and some stations have recorded none.

The ocean still shapes life ashore. Camanchaca fog supplies enough moisture for lichens, algae and some cacti, and creates lomas where seasonal plants support insects and birds. The coast also provides freshwater springs and access to marine products. Chinchorro communities settled along these shores from about 7000 to 1500 BCE; they were sedentary fishers whose territory extended from present-day Ilo to Antofagasta and who practiced elaborate mummification. Later, Spanish-era coastal towns served silver exports from Potosí and other mining centers. In the nineteenth century, sodium nitrate exports brought rapid population growth and drew Chile, Bolivia and Peru into the War of the Pacific. This history joined a forbidding desert to busy Pacific ports and a changing maritime economy.