A bird's eye view of the flooding in Brazil

Weeks of torrential rain in Brazil's southern state of Rio Grande do Sul have left numerous cities and regions underwater, including the airport in Porto Alegre. More than 150 people have died and another 100 are still missing. Sebastian Melo, the mayor of Porto Alegre, described it as “Brazil's worst-ever climate episode."

The metropolis of Porto Alegre is located on the Jacui river. Rescue workers have had to evacuate residents by boat. Some 30,000 people are now living in about 150 emergency shelters. 50-year-old Marcia Leal has already experienced three floods: “You fight to get it all back, and then it's gone again,” she says.

Rebuilding the region will be a Herculean task. The water in flooded Canaos, around 20 kilometers north of Porto Alegre, stretches to the horizon. The full extent of the damage will only be apparent once the water has drained away. Brazil's cities need money, expertise and new technologies to be better prepared for floods in the future.

Porte Alegre, the capital of the flood-hit state, does in fact have comprehensive flood protection, consisting of dikes, dams, and a massive protective wall. However, the system was built in the 1970s: It is outdated, and had no contact with floodwater until 2019, says Leomar Teichmann, an urban drainage engineer. The residents of Porto Alegre were lulled into a false sense of security.

Soccer is a national sport in Brazil. In 2014, the FIFA World Cup was held in Porto Alegre's Beira-Rio Stadium, in front of more than 50,000 spectators. Now, after the floods, the stadium ring is completely surrounded by muddy, brown floodwater, inside and out.

The small town of Encantado on the banks of the Taquari River was also hit by floods. The floodwater brings with it tonnes of thick mud. This doesn't just block roads and bury vehicles; it also clogs sewage and drainage systems. If these aren't cleared in time, subsequent rainfall has nowhere to drain away, resulting in renewed flooding.

A satellite image shows the full extent of the disaster in Porto Alegre. The psychologist Marta Fadrique, who heads the city's mental health service, warns that those affected may develop a lasting fear and dread of new floods - but, she says, this can be overcome.