Abstract: River Noyyal, an important tributary of the Cauvery, was a significant source of water in Coimbatore, Tiruppur, Erode and Karur districts in the 1980s. Since the 1990s, effluent discharge from the dyeing and bleaching units in and around Tiruppur has ecologically damaged the river basin, bringing agriculture to a standstill. Despite judicial intervention and the setting up of common effluent treatment plants, the water quality remains unchanged.

The authors are Assistant Professor, Department of Environmental Management, Bharathidasan University, Tiruchirappalli; Director, Akara Research and Technologies, Chennai; and, Research Scholar, Salim Ali centre for Ornithology and Natural History, Coimbatore respectively. nishadhka@gmail.com


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Reinforcement or upgrading of existing structures to become more resistant and resilient to the damaging effects of hazards.

The Richter scale is a 0-10 logarithmic scale, which defines magnitude of an earthquake.

The frequency, intensity, and distribution of earthquakes in a given area.

Landfall is the event of a storm moving over land after being over water. When a waterspout makes landfall it becomes a regular tornado, which can then cause damage inland.

A scale of wind speed based on a visual estimation of the wind's effects, ranging from force 0 (less than 1 knot or 1 km/h, ‘calm’) to force 12 (64 knots or 118 km/h and above, ‘hurricane’).

A scale of wind speed based on a visual estimation of the wind's effects, ranging from force 0 (less than 1 knot or 1 km/h, ‘calm’) to force 12 (64 knots or 118 km/h and above, ‘hurricane’).

The El Niño-Southern Oscillation (ENSO) is a naturally occurring phenomenon that involves fluctuating ocean temperatures in the equatorial Pacific. The warmer waters essentially slosh, or oscillate, back and forth across the Pacific, much like water in a bath tub.

Epicenter

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An aerosol can be defined as a system of solid or liquid particles suspended in air. Aerosols can vary in size and composition. When these particles are sufficiently large, we notice their presence as they scatter and absorb sunlight.

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