Floods in southern Brazil are a Groundhog Day climate event

In September 2023, an extratropical cyclone struck the southern region of Brazil, causing heavy rainfall and flooding and killing dozens of people. Thousands of others were driven from their homes and city officials declared a state of disaster. Just seven months later, the region is facing similar challenges – although this time the climate events have been worse.

Early in the afternoon of April 26, the National Institute of Meteorology (Inmet) warned of upcoming storms in Rio Grande do Sul, Brazil’s southernmost state. Some parts of the state were expected to receive more than 100mm of rain this weekend, and winds of more than 70 kilometers per hour were expected to produce hail.

Days later, MetSul, a meteorological monitoring company, said the state was at “serious risk” of flooding and landslides due to the heavy rains. Roads would be blocked and crops would be flooded.

The predictions came true, as the state has suffered in recent weeks “the worst meteorological catastrophe” in its history, in the words of Paulo Pimenta, native of Rio Grande do Sul and press secretary of President Luiz Inácio Lula da Silva. Governor Eduardo Leite called the situation a “war-like scenario” and said the state is facing the “most critical moment” ever.

In the last few days of April, the state of Rio Grande do Sul received about 70 percent of the precipitation normally recorded for an entire month. According to Ogmet, a meteorological service, eight of the ten cities where it rained the most on Thursday were in the southernmost state of Brazil.

In Porto Alegre, the state capital, precipitation in April 2024 was more than twice the average for the period 2001-2023, according to data from the National Meteorological Institute.

At least 1.3 million people have been affected by the floods, according to state authorities. As of Tuesday morning, more than 90 people have died in the current crisis, and more than 130 were missing. More than 155,000 people were displaced and more than 48,000 were in shelters. In several cities, entire neighborhoods are flooded. Last week, Mr Leite declared a new state of disaster and was visited by Lula.

The federal government declared a state of emergency on Sunday in 336 of the 495 municipalities in Rio Grande do Sul, helping to accelerate the receipt of federal funds to…