4,500-Year Climate Record Reconstructed from Kondagai Lake

In January 2026, a team of scientists reconstructed one of the most detailed climate records from peninsular India by analysing sediments from the Kondagai inland lake in Sivaganga district, Tamil Nadu, offering fresh insights into monsoon variability, ecosystems and human settlement over nearly 4,500 years.

Key Points:

High-Resolution Climate Record: Scientists analysed 32 closely spaced sediment samples from a little over one metre below the lakebed, enabling unusually high-resolution reconstruction for inland Tamil Nadu, a region highly sensitive to the Northeast Monsoon.
Methods Used: The reconstruction combined stable isotope analysis, pollen studies, grain-size measurements and radiocarbon dating to track rainfall, vegetation shifts, lake levels and flood events.
Key Climatic Phases Identified: The study identified three major Late Holocene climatic phases- the 4.2 ka arid event, the 3.2 ka dry phase, and the Roman Warm Period, linked to monsoon variability and hydrological change.
Archaeological Link: The lake is located near Keeladi, providing crucial environmental context for understanding how Sangam-era urban settlements adapted to climate stress and water scarcity.
Monsoon Baseline for Planning: The long-term monsoon baseline is expected to improve climate forecasting and risk assessment in Tamil Nadu, where droughts, floods and extreme rainfall are recurring challenges.
Water & Disaster Management: Findings could support reservoir restoration, groundwater recharge, tank rehabilitation and climate-smart agriculture in Sivaganga and Madurai, and aid flood-risk mapping in the Vaigai basin.