Delhi and its suburbs woke up this morning to a blanket of smog indicating a spike in air pollution levels, though reports suggest it is better than last year. The Supreme Court had banned the sale of firecrackers in and around the national capital ahead of Diwali to prevent a sharp deterioration in the already poor air quality, but a quiet and promising Thursday evening gave way to noisy and relentless bursting of firecrackers later in the night in many parts of the city. Chennai, which reported a decrease in sale of crackers is choking under a cloud of smog this morning and Mumbai, too, is witnessing a dense haze.