Extreme Monsoon Variability Threatens Marine Life

In April 2025, a new study warns that both extremely weak and strong Indian summer monsoons (ISM) could severely impact marine life in the Bay of Bengal, threatening food security for millions of people dependent on fisheries.

Key Findings

Monsoon Impact on Marine Life: The study reveals that both extreme strong and weak monsoons have led to a 50% drop in marine food available at the surface, especially affecting plankton growth, which is the foundation of the marine food web.
Bay of Bengal's Importance: Despite covering less than 1% of the global ocean, the Bay of Bengal produces nearly 8% of the world's fishery output, crucial for the protein needs of millions living along its coast.
Plankton and Nutrient Supply: Phytoplankton, which produce food and oxygen, are heavily impacted by changes in monsoon rainfall.
Historical Insights: The research looked at fossil shells of plankton over the past 22,000 years, revealing that the Bay of Bengal's marine productivity collapsed during both weak and intense monsoon periods in the past, indicating that future climate change could lead to similar outcomes.