Exploring Artificial Rain in Delhi: Feasibility and Challenges
The severe air pollution crisis in Delhi, especially during the winter months, has prompted discussions on innovative solutions such as artificial rain through cloud seeding. In response to D.O. letters sent by Shri Gopal Rai, the Environment Minister of the Government of the National Capital Territory of Delhi (GNCTD), the Ministry of Environment, Forest, and Climate Change evaluated the viability of cloud seeding as an emergency measure to improve air quality. The ministry sought opinions from the India Meteorological Department (IMD), the Commission for Air Quality Management (CAQM), and the Central Pollution Control Board (CPCB).
Expert Assessment of Cloud Seeding Feasibility
Expert opinions highlighted significant limitations in employing cloud seeding during Delhi’s winter. Winter clouds in the region are mainly influenced by Western Disturbances, which naturally result in rainfall over Northwest India, reducing the necessity for artificial rain. Furthermore, most clouds during winter are at high altitudes (above 5-6 km), making them inaccessible for cloud seeding due to aircraft limitations.
For cloud seeding to be effective, specific conditions, such as the presence of suitable low clouds, are required. However, Delhi’s winter months are typically characterized by a cold and dry atmosphere. Even if appropriate clouds were present, precipitation could evaporate before reaching the ground due to the dry atmospheric layer. Moreover, uncertainties regarding the effectiveness, potential adverse effects, and environmental impact of cloud-seeding chemicals raise additional concerns.
These findings were communicated to the Delhi government via a D.O. letter dated October 30, 2024. Additionally, the Delhi Pollution Control Committee (DPCC) was asked to submit a detailed proposal for further evaluation.
Stakeholder Meeting and Broader Pollution Factors
On November 27, 2024, CAQM convened a meeting with stakeholders and experts to explore the feasibility of cloud seeding for combating Delhi’s persistent air pollution. The discussions emphasized that air pollution in Delhi and the National Capital Region (NCR) stems from various sources, including:
Vehicular Emissions
Industrial Pollution
Dust from Construction and Demolition Activities
Road and Open Area Dust
Biomass and Municipal Solid Waste Burning
Stubble Burning and Firecrackers during Festive Seasons
Post-monsoon and winter months exacerbate these issues due to climatic factors such as low temperatures, stagnant winds, inversion layers, and lower mixing heights, which trap pollutants near the surface. These factors create hazardous air quality levels that are difficult to manage.
Current Measures to Combat Air Pollution
In response to the worsening pollution levels, the government has implemented various measures to mitigate air pollution during the ongoing winter season. While specific details of these initiatives are included in Annexure I of the official communication, they broadly focus on reducing emissions from key sectors and addressing episodic pollution events such as stubble burning.
Conclusion
While cloud seeding might appear to be a promising solution for Delhi’s air pollution crisis, expert assessments underscore its limited feasibility during winter due to unfavorable cloud conditions and potential environmental risks. The government continues to explore other measures and strategies to improve air quality, emphasizing collaborative efforts and comprehensive policies. Addressing the root causes of pollution remains critical to achieving sustainable and long-term improvements in Delhi’s air quality.
