Unprecedented flood disaster in southern Brazil is ‘climate bill’

Brazilian President Inácio Lula da Silva was clear in a press conference on Wednesday: the natural disaster in the south of Brazil did not just happen to the country. Man had a role in this. “This is a warning to all humanity,” he said. ‘Strange things (weather extremes, ed.) place.’

Heavy rainfall is not an unknown phenomenon in the south of Brazil, but rarely has the water caused so much damage and killed so many people. Last week, Porto Alegre, capital of Rio Grande do Sul, was caught in the perfect storm. The city with 1.3 million inhabitants is located only meters above sea level and borders the Jacuí delta, where five rivers flow into Lake Guaíba.

The rivers and lakes could not cope with the heavy rainfall. Lake Guaíba currently has a level of 5.3 meters, more than 2 meters above maximum capacity. Under normal conditions, the lake drains the water to the Lagoa dos Patos (the Lagoon of the Ducks) and from there the water flows from inland through a narrow passage to the Atlantic Ocean.

In addition to the rainfall, Brazil suffered a storm surge that raised the sea level by 2 meters. The precipitation had nowhere to go and thus flooded entire residential areas, highways and even the airport. And the end is not yet in sight: more rain is expected in the southern state. As of Wednesday, the death toll stood at 100 people, with another 130 people missing.

Not only Porto Alegre was affected, more than four hundred of the nearly five hundred municipalities in the state were affected by the rainfall. A large part of the residents are without electricity and without drinking water.

Dehydration

Six months ago, other worrying climate reports came from Brazil. The Amazon region was experiencing a historic drought; rivers have never been so low before. Indigenous groups were in danger because the rivers in which they fished dried up. The dozens of pink freshwater dolphins that washed ashore became the symbol of the drying Amazon.

The weather phenomena are two sides of the same climate coin. “This does not come as a surprise to science,” climate scientist Paulo Artaxo said in the Brazilian newspaper this week Folha de São Paulo. ‘For twenty years now, all climate models have indicated that with rising global temperatures, heavy rainfall and extreme drought are increasing.’

Eight years ago, the Brazilian climate panel PBMC warned of ‘increasing precipitation and heavier river flows’ in the south of Brazil. While the northeast of Latin America’s largest country was vulnerable to drought, cities in the south (east) such as Rio de Janeiro and São Paulo were at greater risk of flooding due to extreme rainfall.

In January, those two cities were indeed hit by violent storms and several people were killed. But that was nothing compared to the disaster that has been unfolding in Rio Grande do Sul since last week. It will take weeks for the water to drain from the city, analysts predict.