High rainfall in S?o Paulo causes floods and landslides, what are the effects of climate change and global warming?

?In early 2023, S?o Paulo was hit by heavy rainfall which caused floods and landslides. This incident left at least 64 people dead with 63 of them in S?o Sebasti?o (Martins, 2023). This is due to the existence of areas of low pressure off the coast of Brazil which carry moist inland flows, causing significant rainfall (Nachtigall, 2023). This increase in rainfall is due to orographic uplift in the mountains of S?o Paulo. The 682 mm fell in just 24 hours at Bertioga which is just outside S?o Sebasti?o. In addition, 395 mm in Guarujá, 337 mm in Ilhabela, and 335 mm in Ubatuba (Davies, 2023). So far the rainfall that has occurred in Bertioga is the largest in the span of 24 hours in Brazil. This rainfall could be one of the highest total non-tropical cyclonic precipitation in the world according to meteorologists at MetSul Meteorologia. This heavy rain caused landslides in the city of S?o Sebasti?o with the most severe impact (Jazeera, 2023). According to The Guardian (2023), this high rainfall also causes flooding to also occur in the cities of the richest parts of Brazil.

?????S?o Paulo is located in the southern hemisphere with a hot season that starts at the end of January and ends in March. Despite entering summer, S?o Paulo still has significant rainfall throughout the year. Even in the driest month there is still a lot of rainfall. According to NOAA (2021), this intensity and precipitation can be affected by climate change. Warm oceans will increase the amount of air that evaporates into the air. Air vapor that collects can produce heavier rainfall. This rainfall has potential impacts, such as soil erosion and an increased risk of flooding due to heavy rains. This change can be driven by global warming which drives the hydrological cycle to increase. According to a study by Tabari (2020), the intensity of extreme rainfall and flooding in all climatic regions increases as air availability increases from dry to wet areas. There is also an increase in the intensification of extreme rainfall and flooding with seasonal cycles of water availability. Given the relationship between extreme rainfall and changes in flood intensity and air spatial availability and seasonality becomes strong as events become less extreme. This is supported by the study of Georgescu et al. (2021), the expansion of urban and greenhouse environments pushes the spectrum of probabilities toward broad increases of extreme precipitation in a region. There is a need for development management that addresses the challenges of landslide flooding which may be driven by climate change caused by greenhouse gases and cities.

Referensi

Davies, R. (2023, February 20). Brazil – 680mm of Rain in 24 Hours Triggers Floods and Landslides in S?o Paulo, Dozens Killed. FloodList. Retrieved March 8, 2023, from https://floodlist.com/america/brazil-floods-sao-paulo-february-2023??

Georgescu, M., Broadbent, A. M., Wang, M., Krayenhoff, E. S., & Moustaoui, M. (2021). Precipitation response to climate change and urban development over the continental United States. Environmental Research Letters, 16(4), 044001. https://doi.org/10.1088/1748-9326/abd8ac?

Jazeera, A. (2023, February 21). Death toll from flooding in Brazil rises to 44. Floods News | Al Jazeera. Retrieved March 8, 2023, from https://www.aljazeera.com/news/2023/2/21/death-toll-from-flooding-in-brazil-rises-to-44?

Martins;, L. B. L. (2023, February 26). SP: Número de Mortes após chuvas no Litoral Norte Sobe para 64. Notícias. Retrieved March 8, 2023, from https://noticias.uol.com.br/cotidiano/ultimas-noticias/2023/02/26/atualizacao-vitimas-sao-sebastiao.htm?

Nachtigall, L. F. (2023, February 19). Chuva de Quase 700 mm inunda Litoral de S?o Paulo e vai seguir. MetSul Meteorologia. Retrieved March 8, 2023, from https://metsul.com/chuva-de-quase-700-mm-inunda-litoral-de-sao-paulo-e-vai-seguir/??

NOAA. (2021). Climate Change Indicators: Heavy Precipitation. EPA. Retrieved March 8, 2023, from https://www.epa.gov/climate-indicators/climate-change-indicators-heavy-precipitation#ref1??

NOAA. (2021). Climate Change Indicators: Heavy Precipitation. EPA. Retrieved March 8, 2023, from https://www.epa.gov/climate-indicators/climate-change-indicators-heavy-precipitation#:~:text=Climate%20change%20can%20affect%20the,heavier%20rain%20and%20snow%20storms.??

Tabari, H. (2020). Climate change impact on flood and extreme precipitation increases with water availability. Scientific Reports, 10(1). https://doi.org/10.1038/s41598-020-70816-2??

The Guardian. (2023, February 23). Brazil floods: Death toll rises to 48 as landslides and looters prevent aid reaching survivors. The Guardian. Retrieved March 8, 2023, from https://www.theguardian.com/world/2023/feb/23/brazil-floods-death-toll-flooding-landslides-looters-sao-paulo-state??

Writer : Salsabila Hana Zyria Tanjung

Editor : Latifa Rizka Andira