The continuing El Niño weather phenomenon led to record rainfall and flooding beginning April 27, 2024, and continuing through early May in Rio Grande do Sul, a state in southern Brazil. Warm water in the Pacific Ocean, affected by El Niño, and very high temperatures in the South Atlantic Ocean contribute to humidity and increase the amount of rainfall.
In some metropolitan and rural areas, rainfall exceeded 12 inches in less than a week. For example, Bento Gonçalves saw 21.39 inches of rain. In Porto Alegre, more than two months of rain fell in just three days. This area normally receives 4.5 inches of rain in April and 4.4 inches in May, but it received 10.18 inches in those three days.
Located on the Guaiba River, Porto Alegre, the state’s capital, is usually a bustling city home to 1.3 million people. With the airport and bus station closed and main roads blocked because of the floodwaters, the city has been virtually cut off, leaving many residents without essential supplies such as food, water and gas. Many streets remain completely flooded after the Guaiba River breached its banks. The river reached a high of 17.4 feet, breaking the previous record set in 1941 of 15.7 feet. Water and electricity services have also been affected. Nearly 500,000 people were without power in Porto Alegre and nearby towns.
The rain is forecast to continue, delaying recovery and hampering search and rescue efforts and distribution of humanitarian aid. The number of casualties continues to grow, and there have been significant economic losses and destruction of infrastructure. Because many communities, including Porto Alegre, are cut off or have limited access, full assessments have not been completed. The airport is underwater, hampering aid from reaching the area.
This stunning photo essay from The Washington Post highlights the immense destruction caused by the flooding. Needs will be high for years to come.
(Photo: Rio Grande do Sul’s security forces work tirelessly to rescue people from flooding in Porto Alegre, May 3, 2024. Credit: Governo do Rio Grande do Sul via X)
One of several major flooding events in Brazil in recent years, the 2024 floods emphasize the need for early warnings for all and a better response to El Niño, La Niña, and other weather patterns and climate change impacts. A recent climate discussion sponsored by the World Meteorological Organization (WMO) took place on May 1, with over 60 member states taking part.
In a video message, WMO Secretary-General Celeste Saulo said, “The impacts of the 2023-2024 El Niño underscore the need to better manage future events. In parallel, human-induced climate change is intensifying impacts of El Niño/La Niña episodes and increasing climate risks. El Niño and La Niña events can be predicted well in advance. This allows society to prepare and thus reduce economic losses and minimize risks to lives and livelihoods. Studies show El Niño Early Warning Systems can provide a two-fold to nine-fold return on investment. Such predictions are a core part of the Early Warnings for All initiative which seeks to expand early warning systems to everyone in the world.”
Following the floods in Brazil in 2022, Reuters reported the flooding “[underlines] a lack of urban planning in low-income neighborhoods throughout much of Brazil, where shantytowns are often built on hillsides prone to collapse. The destruction also comes as scientists begin to question whether abnormal rain cycles in Latin America’s largest nation could be a result of climate change.”
