TIDE – RAINFALL QUOTIENT

TIDE – RAINFALL QUOTIENT

Subject : Disaster Management

Context : To understand if a coastal city is more prone to floods caused by tidal events or extreme rainfall, a team from the Indian Institute of Technology Bombay devised a new metric or measure called the Tide–Rainfall Flood Quotient.

Concept :

• Using the past rainfall data, tidal data, and topography of the region this framework can be applied to pinpoint the major factor at play.
• The team selected three geographically diverse flood-prone coastal regions – Mithi Catchment in Mumbai, Maharashtra, Jagatsinghpur District in Odisha, and Greater Chennai Corporation in Tamil Nadu to test their new metric.
• The new method helped classify these regions into ‘storm-tide dominated’ or ‘pluvial (rainfall) dominated’ regions.
• The metric can help disaster management experts in framing better flood risk management systems directed towards long term planning.

Additional Information

• The C40 Cities report of 2018 notes that by 2050, over 570 low-lying coastal cities will face projected sea level rise by at least 0.5 meters, putting over 800 million people at risk from the impacts of rising seas and storm surges.
• While the inland areas can be flooded due to the heavy rainfall, the coasts are threatened by the impact of tidal surges.