The Other Monsoon: Northeast Monsoon in India (GS Paper 3, Environment)
Context
- India's monsoon season is vital for agriculture, influencing rainfall patterns, productivity, and climate change impacts.
- While the southwest monsoon garners significant attention, the northeast monsoon also plays a crucial role, particularly in southern states.
- Enhanced modeling of its effects is essential for better preparedness and response.
Introduction
- India's southwest monsoon has concluded with an optimistic 8% surplus rainfall.
- The India Meteorological Department (IMD) has successfully forecasted rainfall patterns since July, providing confidence as the focus shifts to the northeast monsoon.
A Shift in Focus to the Northeast Monsoon
Monsoons and the Economy
- As the southwest monsoon recedes, attention turns to the northeast monsoon, which is crucial for regions like Tamil Nadu and Andhra Pradesh.
- This monsoon is defined by winds reversing direction, bringing rains to the southeastern coast.
Characteristics of the Northeast Monsoon
- Timing: The northeast monsoon typically follows the withdrawal of the southwest monsoon around mid-October.
- Geographical Impact: It primarily affects coastal Andhra Pradesh, Tamil Nadu, Kerala, and parts of southern Karnataka. For Tamil Nadu, it serves as the main source of rainfall, contributing about 11% of India's annual precipitation.
Forecast for Post-Monsoon Rainfall
- The IMD projects this year's post-monsoon rainfall to be around 12% above the historical average.
- Despite its limited geographical spread, the northeast monsoon is critical for the agricultural productivity of rice and maize, especially in Tamil Nadu and Andhra Pradesh.
- Deficiencies in rainfall have historically led to significant drops in crop yields.
Impact of Rainfall Variability
Strong Variation Across the Country
- Northeast monsoon rainfall exhibits a variability of nearly 25%, surpassing the southwest monsoon’s 10%.
- This variability can result in years marked by extreme deluges followed by dry spells.
- For instance, the 2015 Chennai floods caused widespread devastation, while in 2019, the city experienced severe water shortages.
Current Expectations and Challenges
- The 2023 forecast indicates a potentially normal northeast monsoon for the second consecutive year, aided by a La Niña event, which typically brings cooler ocean temperatures and supports enhanced rainfall.
- However, forecasting remains challenging; global models have struggled with predicting the exact timing of La Niña's impact this year.
Improving Forecasting Systems
- Advancements in forecasting technology mean that the northeast monsoon is receiving more attention than in the past.
- Improved systems enable better predictions, which are critical for disaster management and agricultural planning.
Conclusion
- While the northeast monsoon is essential for agriculture, particularly in southern India, there is an urgent need for improved modeling to address its implications on urban flooding and climate change.
- With climate uncertainties growing, disaster management agencies must develop robust strategies to incorporate these challenges into their planning and budgeting processes.
- Enhanced forecasting and effective disaster management are crucial to mitigating the risks associated with rainfall variability and climate change, ensuring that the northeast monsoon's impacts are managed effectively.
