🇵🇪Peru

Peru (1,285,216 km²) spans 0°–18°S along South America's Pacific coast, encompassing three distinct climatic regions: the hyperarid coastal desert (Sechura Desert in the north, merging into the Atacama southward) — one of Earth's driest deserts with <30 mm annual rainfall, moderated by the cold Humboldt Current producing persistent garúa fog; the Andes highlands rising to Huascarán (6,768 m, Peru's highest peak) with microclimates from temperate to polar and Peru holding 71% of the world's tropical glaciers including the Quelccaya Ice Cap; and the Amazon basin covering 60% of national territory with tropical rainforest climate (Af/Am) receiving 1,667–5,016 mm annually, including some of Earth's wettest locations in Manu National Park. Peru is the birthplace and heart of the El Niño–Southern Oscillation phenomenon, named by Peruvian fishermen for its Christmas-season arrival.

Coastal Lima (12°S, sea level) averages 15.3°C in August and 23.0°C in February with only 16 mm annual rainfall, shrouded in winter garúa fog yielding just 1,230 sunshine hours yearly — foggier than London. Piura (5°S, 29 m) registers 19.4°C in August and 26.0°C in February–March with 26 mm rainfall. Andean Cusco (14°S, 3,406 m) experiences 8.9°C in July and 12.6°C in November with 693 mm rainfall concentrated October–April.

Peru experiences significant El Niño-driven climate impacts. The 2017 Coastal El Niño event (the strongest since 1925) produced 113 deaths, destroyed over 115,000 homes, generated 300 mm daily rainfall in Piura (three times the annual average), and triggered major landslides. The March 2023 Cyclone Yaku killed at least 8 people, affected 49,000, caused $690 million in damage, and brought record 24-hour rainfall amounts since 1998.

Andean glaciers continue to retreat, with the Quelccaya Ice Cap losing 30 percent of its area between 1979 and 2014 (now at its smallest extent in 6,000 years) and widespread glacier decline including 40 percent volume loss since 1970 in the Huascarán massif. The 31 May 1970 Ancash earthquake (magnitude 7.9) triggered a debris avalanche from Huascarán that impacted Yungay and Ranrahirca with approximately 66,000–70,000 casualties.

Our archive covers 1 Peruvian cities with daily ERA5 reanalysis data going back to 1940. The warmest July averages occur in Lima, around 19.4°C, while Lima records the coldest January nights near 19.2°C. Comparing the last decade against the 1940–1970 baseline, mean temperatures across these cities have risen by about 0.7°C.