The storms and floods in the southern Brazilian state of Rio Grande do Sul result from the combined impact of geographical factors and climate change, said Brazilian experts.
Rainstorm-triggered floods have been hitting Rio Grande do Sul since the end of April, causing severe economic loss and human casualties in that region.
Death toll from storms and floods in Rio Grande do Sul had risen to 154, the civil defense agency said Friday.
“Several rivers, including the Taquari River, flow into the Guaiba basin. The Taquari River, in the mountainous region, is characterized by its steep slope. Sometimes, its water level can rise by one to two meters within an hour, and this can trigger the rapid rise in the water level of the Guaiba River.
In addition, that area also faces challenges from the frequent shifts in wind directions. When the wind blows from the south, it creates a scenario akin to constructing a dam on the Guaiba River, making drainage more difficult. The situation worsens with the increase of precipitation,” said Pedro Camargo, a hydrologist of the disaster relief headquarters in the state.
Heavy rains and floods also hit Rio Grande do Sul last September and November. Meteorologist Katia Valent attributes the frequent occurrence of extreme weather in the state to the influence of El Nino and climate change.
She further warned that more rains are expected to batter the region in the upcoming week.
“In the coming week, the state will be affected by a new cold air mass. This might bring some other problems, as the precipitation is expected to reach 100 to 200 millimeters within the next 48 to 72 hours,” said Valent.
