The warming trend continued in 2021 in Latin America and the Caribbean. The average rate at which temperatures increased was around 0.2 °C per decade between 1991 and 2021, compared to 0.1 °C per decade between 1961 and 1990.
In 2021 the temperature was above the 1981–2010 average in all subregions, with the highest anomaly value of +0.59 (±0.1 °C) in the Mexico and Central America domain, corresponding to +0.97 (±0.1 °C) above the WMO 1961–1990 reference period for climate change.
Glaciers in the tropical Andes have lost at least 30% of their area since the 1980s, with a negative mass balance trend of –0.97 m water equivalent per year during the 1990–2020 monitoring period. Glacier retreat and the corresponding ice-mass loss has increased the risk of water scarcity for the Andean population and ecosystems.
Sea levels in the region continued to rise in 2021 at a faster rate than globally, notably along the Atlantic coast of South America south of the equator, and the subtropical North Atlantic and Gulf of Mexico. Sea-level rise threatens a large proportion of the population, which is concentrated in coastal areas – by contaminating freshwater aquifers, eroding shorelines, inundating low-lying areas and increasing the risks of storm surges.
The “Central Chile Mega-drought” continued in 2021, at 13 years to date constituting the longest in one thousand years, exacerbating a drying trend and putting Chile at the forefront of the region’s water crisis. A multi-year drought in the Paraná–La Plata Basin, the worst since 1944, affected central-southern Brazil, parts of Paraguay and the Plurinational State of Bolivia.
In the Paraná–La Plata Basin, drought-induced damage to agriculture reduced crop production, including of soybeans and corn, affecting global crop markets. In South America overall, drought conditions led to a decline of 2.6% in the 2020–2021 cereal harvest compared with the previous season.
The 2021 Atlantic hurricane season was the third-most active Atlantic hurricane season on record with 21 named storms, including seven hurricanes, and was the sixth consecutive above-normal Atlantic hurricane season.
Extreme rainfall (with record values in many places), floods and landslides induced substantial losses in 2021, leading to hundreds of lives lost, tens of thousands of homes destroyed or damaged and hundreds of thousands of people displaced. Floods and landslides in the Brazilian states of Bahia and Minas Gerais led to an estimated loss of US$ 3.1 billion.
Deforestation in the Brazilian Amazon rainforest doubled compared to the 2009–2018 average, reaching its highest level since 2009. Compared to 2020, 22% more forest area was lost in 2021.
A total of 7.7 million people, in Guatemala, El Salvador and Nicaragua experienced high levels of food insecurity in 2021, with contributing factors including continuing impacts from Hurricanes Eta and Iota in late 2020 and COVID-19 pandemic economic impacts.
South America is among the regions with the greatest documented need for strengthening of early warning systems. Multi-hazard early warning systems (MHEWS) are essential tools for effective adaptation in areas at risk from weather, water and climate extremes.