Syllabus: geographical features and their location-changes in critical geographical features (including water-bodies and ice-caps) and in flora and fauna and the effects of such changes
Current Situation
- The northeast monsoon arrived over Tamil Nadu at least four days early for the second consecutive year. Forecasters project 33% more rainfall than the long-period average, similar to last year. Climate change is concentrating rainfall into short, localised bursts, delivering excessive water quantities. This necessitates reconsidering the traditional notion that excess rainfall is beneficial for the state.
Urban Impact
- Drainage Overwhelm: Concrete and asphalt surfaces prevent absorption causing rapid runoff to overwhelm drainage systems.
- Flash Floods: Low-lying areas are inundated; property damage and transportation disruption occur frequently.
- Power Cuts: Urban authorities cut electricity supply citing loose cables during heavy rainfall events.
- Sewage Overflow: Excessive water volume causes untreated wastewater discharge into streets and waterbodies.
- Health Hazards: Sewage overflow unleashes significant environmental and public health hazards in cities.
Agricultural Sector Vulnerability
- Soil Waterlogging: Suffocates plant roots, washes away seeds and young crops reducing productivity.
- Topsoil Erosion: Nutrient-rich topsoil shed over time causing long-term soil fertility loss.
- Disease Spread: Excessive moisture eases fungal diseases and pest spread devastating crops and yields.
- Financial Losses: Farmers face significant economic losses due to reduced yields and crop damage.
- Water Contamination: Intense bursts wash fertilisers, pesticides into waterbodies, degrading reservoir water quality.
- Vector Breeding: Stagnant water becomes a mosquito breeding ground, increasing malaria, dengue, leptospirosis, Japanese encephalitis risks.
Infrastructure and Wider Impacts
- Water Table Rise: Prolonged rainfall raises water table compromising building foundations, roads and infrastructure stability.
- Structural Damage: High water table exerts pressure on basement walls causing cracks, leaks, mold growth.
- Soil Saturation: Saturated soil loses load-bearing capacity causing foundations to shift, settle causing damage.
- Economic Costs: Building, infrastructure and agricultural land damage requires substantial repair and rebuilding investments.
- Business Disruption: Transport network and business disruptions hamper economic activity across affected regions.
- Social Costs: Flooding and landslips displace communities, injure people, kill vulnerable populations.
- Psychological Impact: Stress, anxiety on affected populations represents significant, often overlooked consequence.