Millions of people across India are celebrating Diwali, the Hindu festival of lights. Families decorate their homes, temples, and streets with small oil lamps and bright lights. These lights celebrate the victory of light over darkness. People also gather with their families, share sweets, and pray together.
Many people also celebrate by lighting firecrackers. However, the celebrations bring serious worries about air pollution, especially in northern India. Cold seasonal weather and smoke from farm fields already make the air dirty. Firecrackers from the festival make the air quality even worse.
In the capital city of Delhi, air pollution has reached dangerous levels. It is the most polluted Diwali festival in the city in ten years. To reduce the smoke, India's top court allowed the sale of certified "green" firecrackers. These special firecrackers are designed to produce 20 to 30 percent fewer emissions than normal fireworks.
However, critics question if these green fireworks will really solve the problem. They worry that air quality will stay poor, and that standard firecrackers will still enter the capital from nearby areas.