Aerosols play an important role in climate change processes. Among the various aerosols, black carbon (BC) has been recognized as the second most important anthropogenic agent for climate change and the primary tracer for adverse health effects caused by air pollution. The increasing concentration of BC in the atmosphere has now become a matter of serious concern, especially in the high Himalayan glaciated region that has the most vulnerable ecosystem with pristine environment, rich biodiversity and pollution-free ambient air quality.

We studied the impact of the odd–even traffic rule (implemented in Delhi during 1–15 January 2016) on primary traffic emissions using measurements of 13 volatile organic compounds, carbon monoxide, carbon dioxide and methane at a strategic arterial road in Delhi (28.57N, 77.11E, 220 m amsl). Whole air samples (n = 27) were collected during the odd–even rule active (OA) and inactive (OI) days, and analysed at the IISER Mohali Atmospheric Chemistry Facility.

Original Source