TAG: GS 1: GEOGRAPHY
THE CONTEXT: In a recent study conducted by the Council on Energy, Environment, and Water (CEEW), an in-depth analysis of India’s monsoon patterns has been carried out, focusing on the tehsil level. The study, spanning four decades from 1982 to 2022, reveals noteworthy trends in rainfall distribution across the country, raising concerns about the potential impact on agriculture, water resources, and overall climate resilience.
EXPLANATION:
Tehsil-level Changes in Rainfall
1. Overall Trends
- 55% Increase, 11% Decrease: Over half of India’s tehsils (sub-districts) have witnessed a rise in rainfall, contrasting with approximately 11% experiencing decreasing rainfall.
- Critical Southwest Monsoon Impact: The reduction in rainfall was particularly prominent during the crucial southwest monsoon, with 68% of affected tehsils experiencing lower rainfall throughout the monsoon months.
2. Geographical Distribution
- Indo-Gangetic Plains and Northeast India: Most affected tehsils are located in the Indo-Gangetic plains, contributing significantly to India’s agricultural production, as well as in northeastern India and the Indian Himalayan region.
3. Study Methodology
- High-resolution Meteorological Data: The study utilized high-resolution meteorological data provided by the India Meteorological Department (IMD) to conduct a granular analysis at the tehsil level.
District-level Extremes
1. Monsoon Year Analysis
- 29 Normal, 8 Above-normal, 3 Below-normal Years: Over the four-decade period, India experienced 29 normal, 8 above-normal, and 3 below-normal monsoon years.
- District-level Disparities: District-level analysis indicates that 30% of India’s districts faced several years of deficient rainfall, while 38% experienced numerous years of excessive rainfall.
2. Extreme Districts
- Dual Extremes: Notably, 23 districts, including major urban centers like New Delhi and Bengaluru, witnessed both deficient and excessive rainfall in varying years.
Localized Wet Rainfall Extremes
1. Increasing Frequency
- 64% Tehsils Experience Increase: A significant finding is that 64% of Indian tehsils reported an increase in the frequency of heavy rainfall days during the southwest monsoon over the past decade.
- Regional Trends: States with high GDPs, including Maharashtra, Tamil Nadu, Gujarat, and Karnataka, showed a prominent pattern of increased heavy rainfall.
2. Short-duration, Heavy Rainfall Events
- Pattern Analysis: The excess rainfall in tehsils with an increasing trend is attributed to short-duration, heavy rainfall events.
Northeast Monsoon Changes
1. Overall Increase
- 10% Increase in Last Decade: Rainfall from the northeast monsoon, occurring from October to December, has increased by more than 10% in approximately 80% of tehsils in Tamil Nadu, 44% in Telangana, and 39% in Andhra Pradesh.
2. Regional Impact
- Peninsular India: The northeast monsoon’s impact is most pronounced in peninsular India, affecting states like Tamil Nadu, Telangana, and Andhra Pradesh.
Implications and Recommendations
1. Economic Considerations
- Union Budget Focus: As India prepares for the Union Budget, the study emphasizes the need to focus on future-proofing the economy against increasingly erratic rainfall patterns.
2. Food Security and Water Resources
- Monsoons’ Impact: Highlighting the critical role of monsoons in agriculture, the study underlines the potential consequences for food production and water resources.
3. Climate Action and Disaster Risk Reduction
- Hyper-local Climate Risk Assessments: To address the challenges posed by changing rainfall patterns, the authors advocate for hyper-local climate risk assessments and action plans, particularly in the face of increasing extreme weather events.
4. Cyclonic Activity Influence
- Arabian Sea and Bay of Bengal Impact: The increase in rainfall during winter months in specific regions is attributed, in part, to cyclonic activity in the Arabian Sea and the Bay of Bengal.
5. Call for Urgent Action
- The urgency of taking proactive measures to adapt to evolving climate patterns has been stressed. The potential impact on lives, livelihoods, and infrastructure, urging a focus on climate action and disaster risk reduction have been emphasized.
Conclusion
- India’s changing rainfall patterns at the tehsil level provides critical insights into the geographical disparities, trends, and potential challenges for various sectors.
- The study calls for a comprehensive and proactive approach to address the implications of these changes, urging policymakers to prioritize climate action, disaster risk reduction, and localized planning to safeguard the nation’s food security, water resources, and overall economic resilience.