With the new rains that are already starting to hit the city of Petrópolis, in Rio de Janeiro, this Thursday (17), specialists heard by the CNN warn of the increased risk of new landslides in the municipality.
The Civil Defense of Petrópolis has already activated at least 14 sirens to warn of heavy rain in the region. According to a report from the National Institute of Meteorology (INMET), the forecast for the state of Rio de Janeiro is for intense rain between 30 and 60 millimeters per hour, and strong winds, which can reach 100 km/h.
The storm, which began to hit the city last Tuesday (15), has already left at least 111 dead, in addition to landslides, buried houses and missing people.
According to the geographer member of the International Commission for the History of Meteorology (ICHM), Carlos Oscar Júnior, the rains in the mountainous region of Rio de Janeiro can last for at least three days.
“This tragedy happened due to a climate convergence zone that operates in the region. After analyzing the weather conditions, we can say that the rains should last for at least three days. This phenomenon in Petrópolis has a lot to do with the relief of the region, which allows the flow of sediments with the force of water. As that place is unstable, any rainfall is very alarming”, declared the expert.
Alexander Costa, professor at the Institute of Geography at the State University of Rio de Janeiro (UERJ), explains that the predominant soil in the Petrópolis region has a more clayey characteristic and takes longer to absorb water.
With the new rains, the expert says that there will be no time for the soil to dry, which increases the likelihood of new landslides, even with moderate rains.
“Soil is made up of particles and it has spaces, called pores, that are eventually occupied by water. When it rains, a greater volume of water occupies these pores, if it rains a lot, it becomes saturated, and loses its absorption power, that is, it no longer infiltrates the water, it no longer absorbs,” explains the geologist.
Also according to Costa, a large volume of moisture accelerates the erosion process of the soil, and sediments drain along with the water. In the case of Petrópolis, the professor explains that, as it is a mountainous region, the slope of the hills makes the soil heavy, and facilitates landslides.
“This situation is accelerated by deforestation, areas of great slope should not be occupied by houses, by the street, for nothing, you have to preserve the original vegetation, to reduce the possibility of landslides. In this case, as it has already rained, the soil still has a very high antecedent moisture content, so the soil is very unstable. It will take a while for it to dry, so any rain, even the weakest, can already cause further damage.”, adds the specialist.
According to the climate manager of the World Resources Institute (WRI), a non-governmental organization linked to the environment, Caroline Rocha, another heavy rainfall in the region could cause a new environmental ‘catastrophe’.
“The city of Petrópolis is vulnerable due to the occurrence of an extreme event. And now we are talking about the possibility of a new volume of rain, which can further aggravate the chaotic situation witnessed in the municipality”, explained Caroline Rocha.
At around 6 pm, the Civil Defense of Petrópolis issued a new mobilization alert for the evacuation of residents from the risk areas of Quitandinha. The report was sent to communities in the region by SMS and communication groups by application.
The measure is due to the volume of rain that affects the city at the moment and will continue, with moderate to strong intensity for the next few hours.
The orientation is that residents of risk areas, who do not have the option of staying with family members in a safe area, go to the support points that operate in the region. In case of an emergency, the public should call 199.
Source: CNN Brasil
