Extreme Weather Events in Argentina: Impacts of Climate Change and Urban Vulnerabilities

Argentina has faced unprecedented extreme heat and flooding, particularly in Bahía Blanca, where over 300 mm of rain fell in eight hours on March 7, 2025. The flooding, coupled with heat alerts across multiple provinces, resulted in significant displacement and economic damage. Researchers are examining the influence of climate change on these weather extremes to evaluate future risks and necessary urban strategies for mitigation.

On March 7, 2025, Bahía Blanca, Argentina, faced an extreme rainfall event, receiving over 300 mm of rain in just eight hours, nearly half of the city’s annual average. This historic event followed a week of over 80 mm of rainfall and came after several days of high heat and humidity. The larger region, including Buenos Aires, had been enduring extreme temperatures exceeding 40°C since mid-February, influencing conditions that intensified the flooding occurring simultaneously.

The flooding affected more than 300,000 residents, claiming 16 lives and displacing 1,400 individuals. The financial toll in Bahía Blanca is estimated at 400 million USD. Concurrently, heat alerts were issued in 15 provinces, and Buenos Aires experienced widespread blackouts impacting traffic and energy demands. While heat-related mortality data is currently unavailable, previous studies indicate heightened mortality risks linked to such heatwaves.

Researchers from multiple countries conducted an attribution study to evaluate how climate change influenced the severity of the rainfall and heat events in the region. The team analyzed rainfall patterns from March 1-7, 2025, observing the interactions between extreme heat and impending precipitation. This analysis is crucial for understanding the overall seasonal impacts of extreme weather events attributed to climate phenomena between December and March.

Findings indicate an increased risk of compounded hydrometeorological hazards in Northern Argentina due to more frequent and intense extreme heat and rainfall events. Urbanization, an aging population, and socioeconomic factors heighten the community’s exposure and vulnerability to these climatic hazards, particularly within densely populated areas where nearly 50% of workers are involved in informal employment.

Data analysis revealed that the extreme heat event is expected to occur approximately once every 50 to 100 years under current climate conditions, whereas such an event would have been virtually implausible in a cooler climate. Climate models project an increase in the frequency and intensity of similar events as global temperatures rise, illustrating a concerning trend for the future of extreme weather patterns.

While weather stations report an increase in heavy rainfall intensity associated with the current level of global warming, gridded reanalysis data suggested a declining trend, indicating discrepancies that hinder definitive conclusions about rainfall responses to climate change. Despite this, models generally predict escalating extreme rainfall occurrences with rising temperatures.

The observed consecutive extreme weather events underline the complexities in managing heightened hazards exacerbated by urbanization and social disparities. As extreme weather phenomena become more prevalent, continued investment in early warning systems, climate-resilient urban planning, and multifaceted preparedness strategies is essential. Initiatives to increase green spaces in urban settings can prove beneficial in mitigating heat and flooding risks simultaneously.

The recent extreme weather events in Argentina underscore the urgent need for comprehensive strategies to address the growing frequency and intensity of hydrometeorological hazards attributable to climate change. Preparations for climate-resilient urban infrastructure and a focus on social inequalities are critical for safeguarding vulnerable populations. Furthermore, as global temperatures continue to rise, the implementation of early warning systems and sustainable urban planning becomes increasingly essential in mitigating the impacts of such disasters in the future.

Original Source: www.worldweatherattribution.org