The catastrophic floods and landslides that struck Sumatra in late November 2025 represent not merely a natural disaster, but a stark manifestation of decades of environmental degradation intersecting with an extreme meteorological event.
This paper analyzes the November 2025 Sumatra disaster—which claimed 1,068 lives and generated economic losses of Rp68.67 trillion (USD 4.11 billion)—through a comprehensive framework encompassing environmental science, disaster risk management, financial economics, and sustainable development policy.
The analysis reveals a critical causation chain: accelerated deforestation in 2024, particularly in the three affected provinces (Aceh, North Sumatra, and West Sumatra), depleted the watershed's natural capacity to absorb extreme rainfall from Tropical Cyclone Senyar, transforming what would have been manageable precipitation into a catastrophic humanitarian crisis.
The disaster's economic toll—exceeding four years of combined palm oil and mining revenue from the affected regions—fundamentally challenges the prevailing development paradigm that prioritizes extractive industries over ecosystem preservation.
