India, once famed for its golden sunlight and blue skies, is witnessing a significant change. The bright and clear sunlight that was integral to its agriculture, lifestyle, and energy is now shrouded by
layers of haze. The country’s skies are gradually losing their light.
A recent scientific study has confirmed this change. Conducted by scientists from Banaras Hindu University, the Indian Institute of Tropical Meteorology in Pune, and the India Meteorological Department, the study titled ‘Long-Term Trends in Sunshine Duration Across India (1988–2018)’ reveals startling facts.
Over the past three decades, the hours of sunlight in India have been steadily decreasing, with many parts of the country now receiving less sunlight than before.
The study indicates that the most rapid decrease in sunlight duration is occurring in the plains of North India, with an annual reduction of about 13 hours. Other regions, including the Himalayan region, the western coast, and the Deccan plateau, are also experiencing a decline.
North India Faces The Brunt
Between 1988 and 2018, the study found that the hours of sunlight decreased across nearly all parts of India. The plains of North India saw an annual reduction of approximately 13 hours, the Himalayas 9.5 hours, the western coast 8.6 hours, central India 4.7 hours, and the Deccan plateau about 3 hours.
In contrast, the change was minimal in the northeastern states, likely due to lower industrial pollution and specific climate conditions there.
Monthly data shows that most parts of the country receive more sunlight between October and May, with a decrease during the monsoon months. However, the Himalayas and northern areas exhibit the opposite trend due to altitude and wind patterns.
Why Is Sunlight Diminishing?
The study concludes that the primary cause of this ‘haziness’ in India’s skies is increasing air pollution. Aerosols from industrial smoke, vehicle emissions, and stubble burning absorb or scatter the sun’s rays before they reach the earth. Furthermore, increasing cloud cover during the monsoon has also contributed to the reduced sunlight.
Two main factors are identified for the decrease in sunlight: air pollution and clouds. Industrial activities, urbanisation, and vehicle pollutants are increasing the amount of fine particles in the air, which either scatter or absorb sunlight, preventing it from reaching the earth. Over time, this process has reduced the duration of daily sunlight, impacting visibility, temperature, local weather, and health.
Dense and long-lasting clouds, especially during the monsoon, block the sun’s rays and amplify the effects of pollution. The combined impact of these factors has created a long-term trend of ‘solar dimming’ in India.
How Less Sunlight Affects Us
The decline in sunlight has significant implications. India’s solar energy policy, which sets ambitious targets for solar energy production, could be affected by the decreasing sunlight. A slight drop in solar radiation can significantly impact energy production, particularly in states with rapidly expanding solar projects.
The agricultural sector will also be impacted. Crop growth and productivity, which depend heavily on sunlight, could suffer if the decrease continues. This would affect the process of photosynthesis and reduce crop yields.
Environmentally, the reduction in solar energy can alter local temperature, humidity, and rainfall patterns, affecting regional ecology and water resources.
What Scientists Are Saying
Scientists stress that the study of sunlight duration is more than just a meteorological statistic; it is an indicator of air quality, energy capacity, and environmental health. It is crucial for the government to enhance regular monitoring, expand the weather station network, and strengthen satellite-based sunlight measurement systems.
From a policy perspective, the decrease in sunlight serves as a warning of increasing pollution. Controlling emissions from industries, transportation, and stubble burning can clear the skies. Incorporating sunlight duration data in energy planning can make solar projects more sustainable.
How To Bring Back The Sunshine
The study’s findings highlight the urgency of addressing the continuous haze over India’s sky. The impacts of this change are far-reaching, affecting everything from solar energy to agriculture. Scientists warn that if immediate steps are not taken to control air pollution and promote sustainable urban development, India’s light could fade even more.
The challenge now is to regain the lost sunlight through clean air, better land use, and ongoing research, ensuring a bright future for India’s energy and environmental stability.
