El Niño would be behind the storm in Rio and SP. Floods, tornadoes, hail, landslides, winds of more than 100 km/h and even a rare formation of roller clouds. In the same week, extreme phenomena caused deaths and destruction in southern Brazil, São Paulo and Rio de Janeiro. Given the succession of events, a question arises: to what extent can El Niño, already installed in the Pacific, be responsible for all this? The response of scientists interviewed by Fantástico is that the phenomenon is already influencing the Brazilian climate, especially in the south, but it does not alone explain all the recent episodes, such as the windstorm that hit São Paulo and Rio de Janeiro on Wednesday. "What we have been observing is an anticipation of the potential influence of this phenomenon", says researcher Lincoln Muniz Alves, from the National Institute for Space Research (Inpe). El Niño is characterized by the abnormal warming of surface waters in the Pacific Ocean in the region close to the coast of Peru. When it intensifies, it alters atmospheric circulation patterns and changes the behavior of rainfall and temperatures in different parts of the planet. According to Giovanni Dolif, researcher at the National Center for Natural Disaster Monitoring and Alerts (Cemaden), the effects have already begun to be felt in Brazil. "It is now already influencing, it is already favoring these severe storms, floods in the South and the expected peak of these events should happen in a few months", he explains. South faces the first most evident effects Rio Grande do Sul was one of the most punished regions this week, with intense rain, hail and tornadoes caused by the passage of a strong cold front. For experts, it is precisely in the south that the influence of El Niño appears most clearly at this time. Historically, the phenomenon favors increased rainfall in the region and can increase episodes of extreme precipitation. Still, scientists warn that El Niño is not the only factor involved. Severe meteorological events depend on the combination of different atmospheric elements, which vary from case to case. The forecasts, however, are worrying. "Brazil needs to be prepared for the likelihood of greater extreme events by the end of the year", warns Lincoln Muniz Alves. Gale in SP and RJ had another origin If El Niño helps explain part of the disasters in the South, experts do not attribute the direct origin of the windstorms that hit São Paulo and Rio de Janeiro to the phenomenon. The explanation involves different atmospheric dynamics. A mass of very cold air advanced from the south towards the southeast. Upon arriving in the region, he found a mass of air warmer than normally expected for winter and blowing in the opposite direction. The clash between these air masses created conditions for the formation of a powerful gust front, capable of producing destructive winds. The greater the temperature difference between them, the more violent the interaction can be. It was this mechanism that led to the felling of trees, collapse of structures, interruptions in transport and accidents that left people dead in both Rio and São Paulo. One of the phenomena that attracted the most attention during the passage of the cold front was the formation of so-called roller clouds, elongated structures that look like cylinders moving across the sky. These clouds form when warm, moist air quickly condenses in an atmosphere marked by strong temperature contrasts and intense winds. Pilot Passos experienced the situation up close during a flight between Rio de Janeiro and an oil platform at sea. "There was no way to measure its size and the speed at which it approached was unbelievable. We didn't imagine it was heading towards us that way," he said. According to him, everything happened in a matter of minutes. "We saw this formation. It was far from the platform. When we made the turn, it was already on our side. It was something very sudden. I had never seen something so fast like that." During the approach to landing on the platform, winds jumped from around 20 km/h to 100 km/h. Faced with the risk, the crew decided to return to Rio. "Safety comes first, always," said the pilot. With two decades of experience and more than 8 thousand hours of flight, Passos claims to notice changes in the behavior of the weather. "It's behaving differently. These are drastic, sudden changes. Even with the forecast, we are surprised by changes and changes." The hottest planet increases the risks In the same week, floods and landslides hit India, floods and an intense heat wave were recorded in China, Germany recorded thousands of deaths associated with extreme heat, England faced a historic drought and Chile suffered from snowfall and floods. According to studies cited by Fantástico, global warming is already increasing the intensity and frequency of several extreme weather events. In Europe, for example, researchers concluded that recent forest fires have become more likely due to the rise in the planet's average temperature. For Giovanni Dolif, a warmer atmosphere creates more unstable and difficult to predict conditions. "A hotter atmosphere becomes more turbulent, more chaotic, and therefore more difficult to predict." The scientists' conclusion is that El Niño already has an influence on the extreme events observed in the country, especially in the south. But it acts on a broader scenario: that of an increasingly hotter planet, where severe meteorological phenomena find favorable conditions to become more intense and destructive. Is El Niño to blame for the storms and winds that scared Brazil? Reproduction / Fantástico GloboPop: click to see the videos from the Fantástico stage Listen to the Fantástico podcasts ISSO É FANTÁSTICO The Isso É Fantástico podcast is available on g1 and the main podcast apps, bringing free