Answer

Introduction

Stretching over 700 km across north-western India, the Aravalli Range acts as a natural ecological barrier against desertification and dust transport. However, rapid degradation is weakening its climatological role, increasing vulnerability of the Indo-Gangetic Plains.

Body

Aravallis as a Climatological Shield

• Dust Barrier: The Aravallis obstruct dust-laden winds from the Thar Desert, reducing dust movement towards northern India.
  Eg: The winds lose speed on hitting the Aravallis, depositing sand as “obstacle dunes” on western slopes.
• Natural Scrubber: Vegetation on the range filters dust and sand particles, improving regional air quality.
  Eg: CEDAR researchers highlighted the “natural scrubbing effect” created by tree cover on Aravalli slopes.
• Desert Check: The range prevents eastward expansion of desert conditions into fertile agricultural regions.
  Eg: The Aravallis stand between the Thar Desert and densely populated Indo-Gangetic plains.
• Climate Regulator: Dust interception influences sunlight penetration and surface temperature, altering local climatic conditions.
• Population Shield: By reducing dust transport, the range protects major population centres from environmental and health impacts.
  Eg: IMD’s Climate Hazards Atlas places Delhi and surrounding districts in a high dust-storm exposure zone.

Degradation & Dust Storms

• Mining Pressure: Extensive mining has weakened hill structures and reduced the range’s barrier function.
  Eg: Environment Ministry’s Aravalli Restoration Framework cites mining of granite, red silica and other minerals.
• Forest Loss: Declining vegetation reduces dust-trapping capacity and increases wind penetration.
• Hill Disappearance: Physical loss of hills has created openings for dust movement.
  Eg: Forest Survey of India (2018) found that 31 of 128 Aravalli hills in Rajasthan had disappeared.
• Gap Expansion: Growing gaps in the range allow dust storms to travel deeper into northern India.
  Eg: Wildlife Institute of India (2009) identified 12 major gaps that have widened due to degradation.
• Dust Intrusion: Even moderate winds now transport dust to the northern plains more frequently.
  Eg: According to Skymet, dust reaches Delhi at wind speeds of 35–40 kmph, unlike earlier when only intense storms carried dust.

Way Forward

• Restore Forests: Undertake large-scale native afforestation to rebuild the natural dust-filtering mechanism.
  Eg: In 2024, the Union Environment Ministry launched the Aravalli Green Wall Project, aiming to create a 1,400-km green buffer across Gujarat, Rajasthan, Haryana and Delhi 
• Regulate Mining: Strictly enforce mining restrictions and reclaim degraded quarry sites.
  Eg: In M.C. Mehta v. Union of India (2002), the Supreme Court ordered the closure of mining activities in parts of the Aravalli range to prevent ecological degradation.
• Close Gaps: Prioritise ecological restoration in identified degraded corridors and hill gaps.
• Strengthen Monitoring:  Use remote sensing and GIS-based monitoring for timely detection of encroachments and degradation.
  Eg: The Forest Survey of India employs satellite-based monitoring through the India State of Forest Report to track changes in forest cover and degradation in the Aravalli landscape. 
• Regional Planning: Integrate Aravalli conservation into air-quality and climate adaptation strategies of northern states.

Conclusion

The Aravallis are far more than an ancient mountain chain, they are a critical environmental shield for northern India. Protecting and restoring this fragile ecosystem is essential for climate resilience, air quality improvement, and sustainable development.

DOWNLOAD PDF