08 July 2014

Observed Holiday Aerosol Reduction and Temperature Cooling over East Asia


Eastern China has one of the heaviest sources of environmental air pollutants since the early 1980s. During a two-week celebration of the annual Chinese Spring Festival Holiday (CSFH) – the most important holiday for the Chinese – more than half of the city-dwelling population heads to the country to celebrate. During this time, the total air pollution rates decrease around the city. However, within the CSFH timeframe is a one-day celebration of the Lunar New Year Day in which air pollution is extremely high, due to the lighted paper lanterns and fireworks displays. To better understand the environmental trends over these time periods, scientists, including a Department of Energy researcher at Pacific Northwest National Laboratory, studied 11 years of long-term observations across 323 meteorological stations. Associated with pollution reduction, the team found that the ambient surface temperature significantly drops over eastern China during the CSFH celebration timeframe. It is unclear how the air quality changes during the short-term CSFH periods over the country, and whether the air temperature has detectable changes in association with the aerosol changes. The amount of pollution reduction is similar to the emission reduction due to the economic slowdown during the holidays, while the intense usage of fireworks and active transport of aerosols seems responsible for the different short-term peaks.

2014.  "Observed Holiday Aerosol Reduction and Temperature Cooling Over East Asia."  Journal of Geophysical Research - Atmospheres 6306-6324, doi:10.1002/2014JD021464.