South America floods highlight climate risks

Three Latin American countries have been badly hit by heavy rains and floods, with experts attributing the disaster to the El Nino phenomenon as well as longer-term climate change. Catastrophic flooding in southern Brazil has overflowed into neighboring Argentina and Uruguay, displacing hundreds of families from their homes as rivers breached their banks.

"The El Nino phenomenon is characterized by equatorial warming while La Nina is associated with droughts," Sergio Jalfin, a meteorologist at the Unife TV channel in Argentina, told China Daily, referring to two distinct periodic weather patterns. "In the context of climate change, it is noticeable that both phenomena are intensifying. Storms, floods and droughts are becoming much more frequent."

Massive flooding in the south of Brazil over the past few weeks has turned into one of the country's biggest weather emergencies ever.

In Argentina's northern city of Concordia, more than 500 people were evacuated in early May after waters from the Uruguay River, which forms the border between Argentina and Uruguay, rapidly rose to dangerous levels. Concordia has suffered its second worst floods in six months, with many urban areas underwater.

Along the Uruguay River, the neighboring towns of Santo Tome and Paso de los Libres have seen flooding as residents are forced from their homes as a precaution.

The floods are exacerbating an already extreme climate emergency across Latin America.

"The direct impact of El Nino in South America is unusually high rainfall over the Argentine coast, Uruguay and southern Brazil," explained Jalfin. "This has been occurring for months. The rains did not just start but began in late 2023 and intensified during the summer."

What is happening on the Uruguay River is connected to events in southern Brazil, as the discharge from all the rain in Brazil flows into the Uruguay River, said Nicolas Bozzani, head of civil defense in Gualeguaychu, an Argentinean city impacted by the rising waters.

"The flooding in Brazil caused high watershed flows into the Uruguay River, as this was the natural drainage path towards the Atlantic Ocean. However, with the Salto Grande Dam regulating water volumes, it had to prepare for and accept the abnormal influx," said Bozzani.

Ahead of the southern Brazilian waters reaching the river, the dam preemptively released water to draw down reservoir levels to the targeted 30-31 meters needed to regulate additional flows. This controlled release raised downstream levels in the Uruguay River, impacting ports and towns along it, explained Bozzani.

"For us, the rising water level in the Uruguay River means a higher mouth level for the Gualeguaychu River. The most visible effect is that it impedes the drainage or emptying of water flowing through this river," he said.

The Caribbean and Latin America witnessed the warmest temperatures on record last year and suffered massive flooding, droughts, heatwaves and storms that have undermined development and displaced millions, according to a new report from the World Meteorological Organization.

According to the report, last year was the hottest on record for Latin America and the Caribbean, with temperatures 0.82 degrees Celsius above the 1991-2020 average. Cycles of extreme heat and severe drought have fueled large wildfires and damaged crops and water security.

Chile's Echaurren Norte glacier alone lost 31 meters in thickness between 1975-2023 due to accelerated melting. Meanwhile, rising sea levels threaten many coastal cities and small island nations in the Caribbean.

Urgent climate action and efforts to build community resilience are needed to spare vulnerable populations from the direct impacts of the climate crisis.

"Beyond early warning systems that enable preparation, the communities along the river, including the Entre Rios province, Concordia and Concepcion del Uruguay, must always be ready to face occasional floods," said Bozzani.

However, underinvestment is impeding effective policy action, with only 1 percent of official development aid currently earmarked for climate adaptation and disaster risk reduction in Latin America and the Caribbean.

Latin America as a whole is responsible for only around 8 percent of global greenhouse gas emissions, but faces disproportionate climate impacts. Given this, calls are mounting for more international support.

"Climate change is an ongoing process that will intensify in the coming years if urgent measures are not taken on a global scale by the world's main powers, such as the US, which are the main emitters of greenhouse gases," said Jalfin, the meteorologist.