HMAP Dataset 16: Peru, South-east Pacific

Although Peru is located in tropical latitudes (between 3 ̊ 23’S and 18 ̊ 21’S), the sea off its shores is characterised by the coldness of the waters of the prevailing Humboldt Current. This constitutes one of the main upwelling regions of the world, and is marked by the highest level of primary production and the greatest fishery based on a single pelagic species (anchovy). This marine ecosystem varies greatly on seasonal, inter-annual (ENSO cycle) and multi- decadal scales. The physical factors which condition the particular climate of this region are the cold surface current flowing towards the equator, the subsurface moving towards the South Pole with its oxygenated undercurrent, the Andes mountains with peaks over 6000 metres above sea level, and the south-eastern trade winds, which form part of the South Pacific Anti-cyclonic gyre. Upwelling determines most of the biological processes in this ecosystem.