This blog is the joint effort of Zhou Yajing, Clare Auld-Brokish, and Pan Zhiming.
Carbon emissions associated with China’s transportation sector in 2019 accounted for 10% of the country’s overall annual emissions, with road traffic making up over 70% of this figure. As ongoing economic development continues to add to the numbers of motor vehicles on the road, pressure to reduce emissions from the transportation sector will only increase without a green transformation.
The A-S-I (avoid, shift, and improve) approach has been widely adopted to reduce carbon emissions in the transportation sector. “Avoid” refers to smart urban land-use plans that reduce private car use by establishing compact cities to reduce trip frequency and lower average trip length.
图片@Andrew Gook on Unsplash
“Shift” encourages residents to substitute the use of private vehicles and other emissions-intensive modes of transportation with low emissions options like public transportation, walking, and cycling. The third pathway, “improve”, refers to increasing the energy efficiency of both traffic-related infrastructure and means of transportation. “Shift” has the highest cost-performance ratio of the three pathways because the construction of walking paths and bicycling infrastructure is relatively low-cost and can result in the adoption of zero-emission short-distance travel. Comparatively, “avoid” is the most difficult to implement because it relies on improvements and revisions to city planning and urban land use. It also requires high levels of investment for improvements such as enhancing fuel efficiency or replacing petrol vehicles with EVs.
The emissions reduction potential of active transit (biking and walking) is quite large. Factoring in the whole lifecycle emissions associated with motor vehicles, emissions associated with China’s passenger vehicles totaled 21 kg per 100 km per car in 2019. Statistics from private vehicle use in Beijing in 2020 show that if only half of the trips in passenger vehicles were replaced by transport on foot, by bicycle, or using another active transit means, the city could avoid roughly 20% of its annual total transportation carbon emissions.
However, the development of active transit has encountered a few roadblocks, the most prominent being the encroachment of motorized vehicles into designated non-motorized lanes which has led to the deterioration of walking and bicycling conditions. To encourage the uptake of active transit travel, cities must secure road rights for these types of transit to prevent stalled and parked cars from blocking crucial pathways. Cities also need to ensure the security of pedestrians and cyclists by laying down appropriate crosswalk infrastructure and improving signage. Adding benches and planting trees along them can also encourage more people to partake in active transit.
To raise public and governmental awareness about the importance of pedestrian-friendliness for active transit, NRDC developed an index in 2013 to evaluate the walkability of Chinese cities and has since published a series of walkability reports. In the fifth “Walkability Report” published this year, NRDC collaborated with Professor Long Ying at the Tsinghua University School of Architecture and his team to evaluate recent developments in pedestrian infrastructure across the country. The research covers publicly available data gathered from 45 cities and compares images of over 20,000 spots from the walkways across multiple years to evaluate changes in ten metrics, including the presence of specialized walking paths, establishment of road crossing infrastructure, and patterns of use.
The research found that over the last few years, a variety of cities have adopted measures to improve the safety of their walking paths, including providing physical separation between motorized and non-motorized vehicle lanes, repairing walking paths, and enhancing cross walk infrastructure. But although cities have made great strides in preserving the road rights of active transit travelers, many still lack an adequate number of cycling pathways, many of which continue to be blocked by parked cars. In addition, many cities have yet to improve the comfort of their pathways.
Beijing especially has made great improvements to its active transit systems over the last few years by continuing to widen its sidewalks and improve its bicycling infrastructure. As a result, 47% of the trips logged around the city in 2020 were taken using active modes of transportation, up from 40% in 2016. Among these, the proportion of bicycle trips has increased 50%. Beijing’s first bicycle highway, inaugurated in 2019, has supported over 4 million trips, successfully encouraging residents to alter their transit choices.
Promoting active transit will not only require improvements to urban street infrastructure but also adoption by residents. In the coming months, we will expand our work to examine transit experiences, resident opinions, and other factors that contribute to active transit desirability. In this way, we hope to help cities develop more comprehensive policies, incentivize residents to change their transit behavior, and reduce carbon emissions, ultimately helping the transportation sector to achieve its “dual carbon” goals.
