Geovisualizing cancelled air and high-speed train services during the outbreak of COVID-19 in China.

Introduction

The rapid human-to-human transmission of COVID-19 was formally recognized and announced in Wuhan, China, on January 20, 2020. Zhang et al. (2020) suggested that air and high-speed train (HST) services have played an important role in the spread of COVID-19 across Chinese cities. In China, locking down cities and travel restrictions were major control measures used to stop population migration and slow down the spread of the COVID-19 pandemic (Wei et al., 2021). Therefore, Chinese airlines and China Railway cancelled many flights and HSTs due to greatly reduced intercity traffic demand and travel restrictions announced by the government. This paper aims to visualize the cancelled air and HST services during the outbreak of COVID-19 in China, and compares them with the regular schedules.

Data and methods

Data from February 14, 2020 were selected for several reasons. First, the number of cities in China affected by COVID-19 reached its peak on that day, and then kept stable until April 2020. Second, the number of daily flights fell to their lowest level on February 13 and February 14 since the outbreak of COVID-19, and the number of airports without any flights reached a peak on February 14 according to the China Aviation Daily (http://news.carnoc.com/list/529/529543.html). Third, the passenger volume by air transport and HSTs reached its lowest level on February 13 and February 14 according to the Ministry of Transport of the People's Republic of China (http://www.mot.gov.cn/).

In this study, the flights/HSTs of each airport (station) were calculated as the accumulative frequencies of domestic departures, stopovers, and arrival flights (HSTs) on February 14, 2020. In cities with more than one airport or HST station in their municipal districts, the flights/HSTs of each airport or station were combined. Since all scheduled, operated and cancelled flights/HSTs of each city were collected, the cancellation rate was defined as the ratio of cancelled flights/HSTs to the regularly scheduled quantities. The data were obtained from VariFlight (http://www.variflight.com/) and the China Railway Customer Service Center (http://www.12306.cn/mormhweb/). Fig. 1 unveils the geography of cancelled and operated flights and HSTs at the city level.

Fig. 1

Impacts of COVID-19 on air and HST services in China, February 14, 2020.

Note: Borders in the figure refer to the Ministry of Natural Resources of the People's Republic of China (http://www.gov.cn/guoqing/2005-09/13/content_5043917.htm).

Comparing the cancelled air and HST services

Chinese airlines cancelled 81% (9795) of domestic flights, and the average cancellation rate at the city level was 78%. Forty-eight (24%) cities closed their airports temporarily. These cities tend to be the smallest air markets. Conversely, the share of cancellations was smaller and roughly similar across the largest and medium-sized cities' airline markets. As a result, the geography of the largest volumes of cancellations matches the geography of the busiest airports, including Beijing, Shanghai, Guangzhou and Shenzhen (Fig. 1a).

As for high-speed rail, China Railway cancelled 32% (2386) of HSTs, and the average cancellation rate of each city was 40%. Only 17 (7%) cities closed their HST stations. Spatially, the cancellation rate of HSTs at the city level (Fig. 1b) followed a decreasing, circular structure around Wuhan, where the first confirmed COVID-19 case in China was reported. Besides, cities with a large number of cancelled HSTs and high cancellation rates were distributed mainly in megacities, such as Guangzhou, Shenzhen, Chongqing, and Chengdu, and nearby provincial capitals, such as Changsha and Zhengzhou. That is because when China started its lockdown of Wuhan, well connected (megacities and nearby provincial capitals) and nearby cities (most in Hubei Province) cancelled their connections with Wuhan. The cancellation rates of HSTs were high, as shown in Fig. 1b. Since Wuhan is an important land transport hub between Guangzhou and Beijing, Guangzhou has a higher connection with Wuhan by HST than Shanghai, so the former had higher cancellation rates of HSTs than the latter.

We found that many more flights than HSTs were cancelled because China's air transportation has been gradually deregulated since the 1980s and airlines have more power to re-schedule flights according to market demand (Wang et al., 2016). However, China's high-speed rail sector remains more state-owned and highly regulated (Li et al., 2019), so HST cancellations were more likely an action to prevent or slow down the spread of COVID-19 than a reaction to market demand. This viewpoint could be further confirmed by considering the actual number of passengers on flights and trains on February 14, 2020—the two numbers decreased by 91% and 92% of the volume on the same day in 2019, respectively. In other words, although the cancellation volume and rate by flights and HSTs were different during the COVID-19 pandemic, the real number of passengers travelling by both transport modes decreased at a similar amplitude.

Conclusions

This paper analyzed the transport networks of flights and HSTs during the outbreak of COVID-19 in China. We found that the operation of flights and HSTs was significantly affected by the pandemic, and the two cancelled transport services show significantly different spatial structures due to their degree of (de)regulation and to governance in China. Both transport modes adjusted their services to slow down population mobility to prevent the spread of COVID-19. However, Chinese air transportation is less regulated, and airlines adjusted their flight schedules more according to market demand to reduce monetary losses. The high-speed rail sector in China is still highly regulated and responded to the market slowly. This paper chose only one day as a representative period to demonstrate cancellations in the transport network, and the dynamics during and after the outbreak of COVID-19 could be further discussed.

Authorship statement

Jiaoe Wang: Conceptualization, Formal analysis, Writing-original draft, Writing-review & editing, Funding acquisition; Delin Du: Visualization; Li Ma: Writing - review & editing.