Three cyclones hit southern Brazil in less than 30 days. The link to global warming is discussed by experts

While Europe suffers from unprecedented heatwaves, southern Brazil has been targeted by intense extratropical cyclones. Within just thirty days, between June and July, three cyclones hit at least 52 cities in the state of Rio Grande do Sul, causing disruptions for at least 17,000 people, along with three deaths and severe losses for agriculture.

These extreme meteorological phenomena, characterized as low-pressure atmospheric systems, brought winds exceeding 140 km/h, heavy rains reaching 300 mm, hailstorms, and flooding.

In the state of Paraná, another 20 municipalities were severely affected by gusts of wind reaching 90 km/h. In Santa Catarina, the mountainous region recorded winds close to 147 km/h, leaving around 300,000 homes without electricity.

The perception of the population and experts is that these extreme weather events are becoming more frequent. According to a survey by the Institute for Technology and Society, released on June 20, 90% of Brazilians acknowledge more environmental disasters, and 94% believe in real global warming, with 74% attributing it to human action.

Environmentalists and meteorologists point to climate change and global warming, driven by rising ocean surface temperatures, as responsible for this intensification. They explain that warmer oceans provide the energy and moisture necessary for the formation and intensification of these low-pressure systems, which give rise to cyclones, primarily in oceanic areas, but can also impact coastal regions, as seen in Brazil’s southern coast.

Although it is not possible to directly attribute specific events to global warming, long-term studies analyzing frequency and intensity data, as well as correlations with other global events, will help confirm the effects of Earth’s rising temperature and its relation to environmental disasters. This contextual perception is already reflected in research, such as the one conducted by the ITS.

According to Ana Toni, Climate Change Secretary at the Ministry of Environment and Climate Change, from Brazil, present at the press conference releasing the survey results, in 2022, more than 520 Brazilians died due to extreme weather disasters, and over 7,300 were displaced.

Given these alarming numbers, Ana Toni stated that the current Brazilian government has climate as a cross-cutting theme in 17 ministries, in addition to the Ministry of Environment, of which she is part. She emphasized, “Unfortunately, climate change has already arrived, with a temperature increase of 1.1 degrees, whereas the Paris Agreement aimed for 1.5 degrees only by 2100. We now perceive that we will reach this much sooner than we imagined, and the consequences will be truly severe.” She added that the Brazilian government is making an enormous effort to comply with the internationally agreed adaptation agenda.

A study conducted by Tércio Ambrizzi, a professor of Atmospheric Sciences at the University of São Paulo, showed some years ago that cyclones did not increase in number but in intensity. “In principle, there is a relationship with climate change. With the atmosphere accumulating much more energy due to the warming the planet is undergoing, caused by greenhouse gas emissions, these systems are becoming increasingly intense,” he says.

Flávio Varone, coordinator of the Agroclimatic Monitoring and Alerts System (Simagro), provides some perspective, explaining that “the occurrence of cyclones is quite common in the state, especially in autumn and winter. In many cases throughout history, there has been more frequent repetition in certain periods due to the prevailing atmospheric patterns. This is what happened in recent weeks.” According to the expert, there are still not enough data to assert whether cyclones are becoming more frequent, as it requires several years of observation and records.

One of the anticipated effects of global warming, according to the UN Intergovernmental Panel on Climate Change (IPCC), is precisely the increased frequency and intensity of extreme events. A warmer South Atlantic than average near Argentina, Uruguay, and Southern Brazil, for example, may lead to greater oceanic evaporation, higher humidity, and thus more energy for cyclone intensification.

Although conclusive studies on the real impact of climate change on the increased volume and intensity of cyclones are yet to be conducted, and there is still some disagreement among experts, urgent measures must be taken to reduce greenhouse gas emissions and limit global warming.

What no one seems to doubt is that individual and collective actions, together with government policies and international agreements, can play a crucial role in mitigating the effects of climate change and protecting vulnerable communities from extratropical cyclones and other extreme weather events.