Professor Kenichi Tonokura and a graduate student of Hiroo Hata (3rd year doctoral student) at the University of Tokyo have revealed that there are regional differences in ozone concentration fluctuations in the Kanto region in the summer due to the introduction of next-generation automobiles.
Volatile organic compounds (VOCs) and nitrogen oxides (NOx) are involved in the production of photochemical oxidants, and automobile exhaust gas is known as an anthropogenic source.The introduction of next-generation vehicles is expected to reduce carbon dioxide emissions from automobiles as well as VOC and NOx emissions, but the environmental impact assessment that accompanies them has hardly been carried out.
The research group is working on changes in ozone concentration in the Kanto 1 metropolitan area and 6 prefectures in the summer caused by the introduction of next-generation vehicles such as hybrid vehicles and zero-emission vehicles (electric vehicles and fuel cell vehicles that do not emit greenhouse gases and air pollutants). , The study was conducted by simulation based on the atmospheric chemical transport model.
As a result, it was found that if all current passenger cars were replaced with hybrid cars, the ozone concentration would increase mainly in the metropolitan area, which is a densely populated area, and the ozone concentration would decrease in the suburbs.On the other hand, when all passenger cars were replaced with zero-emission vehicles, the ozone concentration was almost unchanged in the Tokyo metropolitan area.
In addition, if all passenger cars and heavy-duty vehicles (trucks) are replaced with hybrid vehicles or zero-emission vehicles, the ozone concentration will increase mainly in the Tokyo metropolitan area and ozone in the suburbs, as in the case of replacing all passenger vehicles with hybrid vehicles. It was confirmed that the concentration decreased.
The results of this time are that the introduction of next-generation automobiles may not be effective in reducing ozone concentration, especially in the Tokyo metropolitan area, and that VOC and NOx emissions from other emission sources are emitted at the same time as the introduction to improve air quality. It suggests that simultaneous reduction of the above is necessary.
Paper information:[Scientific Reports] Impact of next-generation vehicles on tropospheric ozone estimated by chemical transport model in the Kanto region, Japan
