The Impact Of Winter Heating On Air Quality In North China

With the continuous development of global economy, the living standards of the people are improving day by day and their requirement for air quality is also improving. Hazy weather often happens in North China during winter. What are the reasons for frequent hazy weather and how to cope with it effectively? People are concerning about those questions recently. Scholars both at home and abroad point out that winter heating in North China could be the main reason. However, what is the exact extent of the winter heating on aggravating air pollution remains unknown. In order to find it out, this study will use a daily panel of 29 cities in North China during November 1,2013 to June 30,2014. After controlling for weather conditions, including the daily maximum temperature, minimum temperature, maximum wind speed, rain and snow, this study employs regression discontinuity design. The basic idea of employing regression discontinuity design is that there is a clear boundaries between heating period and non-heating period without system differences on weather conditions, thus the only difference is whether the heating is on or not. Therefore, local random grouping could be a few days before and after winter heating. The regression discontinuity design can be used to identify the causality of coal-fired winter heating on air quality. Results from regression discontinuity design show that air quality is improving obviously after stopping winter heating from mid-March.When considering the fuel of winter heating in North China is coal, it is easy to know that the pollution does not happen immediately but accumulates over time and the air quality of one day may be associated with air quality over the past few days. Therefore, this study builds a two-way panel fixed effect model. Results from the panel estimation show that air quality index is bigger during the heating period than the non-heating period. As the end of winter heating, air quality index and concentration of various pollutants have been obvious declined. The air pollution is more serious during heating period than non-heating period even the factories were closed during Chinese New Year holiday. Thus, the deterioration of air quality during heating period could be the winter heating and the weather conditions. The higher is the daily maximum temperature, the higher is the air pollution level. The higher is the daily minimum temperature, the lower is the air pollution level. The smaller is the wind speed, the less conductive to the spread and convey of the pollutants is. Results show that the effect of rain on pollutants is more significant than that of snow.Based on those results, this study puts forward some suggestions. Firstly, enlarge the coverage of central heating and strengthen the technical modification of existing boilers and generators. Secondly, focus on improving the efficiency of heating and promote the use of alternative clean energy. Use high quality coal, upgrade scattered boiler rooms, reduce the heat loss of heat pipes in the conveying process and promote central heating in the rural areas. Thirdly, according to the actual heating demand of heating objects to determine the construction scale of central heating projects, avoid wasting energy because of improper planning. The last but not the least, in the long run, vigorously promote clean energy. All governments are urgent needed to invest in upgrading the heating infrastructure and subsidies to promote the use of clean energy, so as to achieve the optimal benefits of the whole society.