Climate change driven by human actions provided an increase in the intensity of the rains that hit the Northeast of Brazil in late May and early June, mainly in the state of Pernambuco.
According to researchers, without global warming, the events that took place would be a fifth less intense.
The information is from a study by the World Weather Attribution, released this Tuesday (5). The research was carried out by scientists from Brazil, the United Kingdom, the Netherlands, France and the United States.
The analyzes were carried out using climate models that simulate the meteorological event in a scenario without the emission of greenhouse gases and in the current scenario, with a global warming of about 1.2°C.
Climatologist Friederike Otto, from the University of Imperial College London, in the United Kingdom, explains that the objective of this type of study is to analyze the relationship between intense weather events and climate change. According to her, this is important to understand the possibilities of similar events happening and what they would be like without climate change.
The researcher Lincoln Alves, from INPE (National Institute for Space Research), says that the work included the characterization of the event, to understand how rare the rains were compared to the historical period.
We selected 75 rainfall stations in the region that had data from at least the 1970s to carry out the study. The analyzes were made from the amount of rain that fell in the region in clippings of a period of seven days and a period of 15 days.
Such rare weather events are more likely to happen today than in a no-global warming scenario. However, from the study it is not possible to measure how much climate change causes these events to happen in the future.
Between the 27th and 28th of May, the state of Pernambuco received in 24 hours more than 70% of the rain expected for the whole month. In Pernambuco alone, at least 129 people died as a result of the rains. Other states such as Alagoas, ParaÃba, Rio Grande do Norte and Sergipe were also affected.
Since last weekend, storms have returned to concern some states in the Northeast. Eight people died and dozens of cities entered emergency situations in Alagoas, Pernambuco and Rio Grande do Norte.
Another element pointed out by the researchers that aggravated the consequences of the rains in the metropolitan region of Recife were the vulnerability problems of the population. The increase in unplanned urbanization in areas at risk of flooding and steep slopes has increased people’s exposure to risks caused by rain.
According to Edvânia Pereira dos Santos, from the Pernambuco Water and Climate Agency (Apac), the city of Recife and the metropolitan region are very vulnerable, due to factors such as high population density and the fact that the city was built around rivers. .
According to Alexandre Köberle, a researcher at the Grantham Institute at Imperial College London, the warning systems carried out by municipal, state and federal agencies help to reduce the damage in this type of tragedy. According to him, these systems can be improved so that more effective early actions are carried out.
Santos, who was part of the study, explains that Apac works in partnership with the Civil Defense to issue such alerts and guide the population.
According to her, the agency has been working to improve communication with the population about the importance of weather alerts and about measures to be taken. According to her, many people do not see the importance of warnings or do not know how to proceed to avoid more serious consequences.
Santos says that since March, the agency has been monitoring the possibility of heavy rains this year, due to phenomena such as La Niña and the warming of the Atlantic. With these forecasts, Civil Defense acts to take the possible and necessary measures.
