Impact of the COVID-19 pandemic on urban human mobility - A multiscale geospatial network analysis using New York bike-sharing data

Similar cities, but diverse carbon controls: Inspiration from the Yangtze River Delta megacity cluster in China

Addressing global uneven urban development and the urgent need to reduce carbon emissions (CE), this study presents a new method for calculating urban socioeconomic development indexes using a variety of data sources. Using the Yangtze River Delta as an example, we categorize urban areas into core, transitional, and peripheral cities. With the help of extended Kaya-index decomposition models, we evaluate the effects of regional industrial growth, consumer markets, and spatial expansion on urban CE. The research explores differences in CE drivers across and within these city categories. Our findings reveal that in core cities, 31.5 % of CE is due to the industrial structure and 14.9 % due to population density. In transitional cities, CE increases by 60.22 % primarily due to industrial structure and consumer consumption. Peripheral cities, on the other hand, have a complex set of causes for CE, with per capita living, spatial expansion, population size, urbanization, and consumption limitation contributing to 91.97 %, 10.73 %, 14.2 %, 9.34 %, and 24.92 % of CE respectively. Varied factors influence CE intensity differences within each city group. Cleaner production technologies and potential carbon reductions in consumption and industry are identified as key strategies for compensating CE reduction. We propose the adoption of carbon function zoning in urban clusters to leverage the role of carbon function in each area. Territorial spatial planning should ensure a balanced layout of production, living, and ecological functions. Residents' consumption, being the key factor driving CE, must transition toward green, low-carbon consumption, reinforced by societal norms and responsibilities. This research provides valuable theoretical and practical insights into urban classification and CE reduction strategies.

Evolvement patterns of usage in a medium-sized bike-sharing system during the COVID-19 pandemic

The global outbreak of COVID-19 has fundamentally reshaped human mobility. Compared to other modes of transportation, how spatiotemporal patterns of urban bike-sharing have evolved since the outbreak is yet to be fully understood, especially for bike-sharing systems operating on a smaller scale. Taking Pittsburgh as a case study, we examined the changes in spatiotemporal dynamics of shared bike usage from 2019 to 2021. By distinguishing between weekday and weekend usage, we found different temporal patterns between trip volume and duration, and distinct spatial patterns of within- and between-region rides with respect to naturally separated regions. Overall, the results illustrate the resilience and the vital role of bike-sharing during the pandemic, consistent with previous observations on bike-sharing systems of a larger scale. Our study contributes to a comprehensive understanding of bike-sharing that calls for more research on smaller-scale systems under disruptive events such as the pandemic, which can greatly inform decision-makers from smaller sized cities and enable future studies to compare across different urban regions or modes of transportation.

Estimating pandemic effects in urban mass transportation systems: An approach based on visibility graphs and network similarity

The COVID-19 pandemic has caused unprecedented disruptions to urban systems worldwide, but the extent and nature of these disruptions are not yet fully understood when it comes to transportation. In this work, we aim to explore how social distancing policies have affected passenger demand in urban mass transportation systems with the goal of supporting informed decisions in policy planning. We propose an approach based on complex networks and clustering time series with similar behavior, investigating possible changes in similarity patterns during pandemics and how they reflect into a regional scale. The methods shown here proved useful in detecting that lines in central or peripheral regions present different dynamics, that bus lines have changed their behavior during pandemic so that similarity relations have changed significantly, and that when social distancing started, there was an abrupt shock in the properties of daily passenger time series, and the system did not return to its original behavior until the end of the evaluated period. The approach allows to track evolution of the community structure in different scenarios providing managers with tools to reinforce or destabilize similarities if needed.

Who changed and who maintained their urban bike-sharing mobility after the COVID-19 outbreak? A within-subjects study

The COVID-19 pandemic has remarkably impacted urban mobility. All non-essential movements were restricted in Valencia (Spain) to contain the virus. Thus, the transport usage patterns of Valencia's bike-sharing system (BSS) users changed during this emergency situation. The primary objective of this study was to analyse the behaviour patterns of BSS users in Valencia before and after the COVID-19 outbreak, specifically those who maintained or changed their transport routines. A within-subjects comparison design was developed using a group of BSS users before and after the onset of the pandemic. Data mining techniques were used on a sample of 4355 regular users and 25 variables were calculated to classify users by self-organising maps analysis. The results show a significant reduction (40 %) in BSS movements after the outbreak during the entire post-outbreak year. There was some recovery during the rest of 2020; however, this has yet to reach the pre-pandemic levels, with variations observed based on the activities performed in different areas of the city. Of the users, 63 % changed their BSS use patterns after the onset of the pandemic (LEAVE group), while 37 % maintained their patterns (REMAIN group). The user profile of the REMAIN group was characterised by a general reduction of approximately 35 % of journeys during 2020, with a slight increase in morning movements compared to those made in the evening. These users also presented an equivalent number of cycling days to those of the previous year, reduced the number of connections and increased the network's density and the travelling speed. These results can be useful in estimating the percentage of people who do not vary their usual behaviour during emergencies. Finally, several policy implications are outlined based on the findings.

Investigation on changes in the usage patterns of Seoul Bike usage patterns owing to COVID-19 according to pass type

Human mobility has been significantly impacted by varying degrees of social distancing and stay-at-home directives that have been implemented in many countries to prevent the spread of COVID-19; this effect was observed regardless of the mode of transportation. Several studies have indicated that bike-sharing is a relatively safe option in terms of COVID-19 infection, and more resilient than public transportation. However, previous studies on the effects of COVID-19 on bike-sharing, rarely considered the type of pass in their investigation of the pandemic-induced changes in usage patterns of shared bikes. To overcome this limitation, this study used trip records obtained from Seoul Bike to investigate the changes in usage patterns of shared bikes during the COVID-19 pandemic. The spatiotemporal usage patterns were characterized in this study based on the type of pass. Additionally, using t-tests and k-means clustering, we discovered significant factors that influenced changes in one-day pass usage rates and temporal usage patterns at the station level. Finally, we constructed spatial regression models to estimate changes in bike rentals caused by COVID-19 based on pass type. The findings provided a comprehensive understanding of how bike-sharing usage varies depending on pass type, which is closely related to shared bikes trip purposes.

Examining the causal relationship between bike-share and public transit in response to the COVID-19 pandemic

As urban transportation systems often face disruptive events, including natural and man-made disasters, the importance of resilience in the transportation sector has recently been on the rise. In particular, the worldwide spread of the COVID-19 pandemic resulted in a significant decrease in citizens' public transit use to avoid unnecessary physical contact with others. Accordingly, bike-share has been highlighted as one of the sustainable modes that can replace public transit and, thus, improve the overall resilience of the urban transportation systems in response to COVID-19. This study aims to examine the changes in causal relationships between bike-share and public transit throughout the COVID-19 pandemic in Seoul, Korea. We analyzed bike-share and public transit ridership from Jan 2018 to Dec 2020. We developed a weekly panel vector autoregressive (PVAR) model to identify the bike-transit relationships before and after the pandemic. Our results showed that COVID-19 weakens the competitive relationships between bike-share and bus transit and modal integration between bike-share and subway transit. This study also found that bus and subway transit were more competitive with each other after the outbreak of COVID-19. The study's findings suggest that bike-share can increase the overall resilience of the urban transportation system during the pandemic situation, particularly for those who rely on public transit for their mobility.

Impacts of COVID-19 on bike-sharing usages in Seoul, South Korea

The COVID-19 pandemic and social distancing restrictions have had a significant impact on urban mobility. As micro mobility offers less contact with other people, docked or dockless e-scooters and bike-sharing have emerged as alternative urban mobility solutions. However, little empirical research has been conducted to investigate how COVID-19 might affect micro mobility usage, especially in a major Asian city. This research aims to study how COVID-19 and other related factors have affected bike-sharing ridership in Seoul, South Korea. Using detailed urban telecommunication data, this study explored the spatial-temporal patterns of a docked bike-sharing system in Seoul. Stepwise negative binomial panel regressions were conducted to find out how COVID-19 and various built environments might affect bike-sharing ridership in the city. Our results showed that open space areas and green infrastructure had statistically significant positive impacts on bike-sharing usage. Compared to registered population factors, real-time telecommunication floating population had a significant positive relationship with both bike trip count and trip duration. The model showed that telecommunication floating population has a significant positive impact on bike-sharing trip counts and trip duration. These findings could offer useful guidelines for emerging shared mobility planning during and after the COVID-19 pandemic.

Short- and long-term effects of COVID-19 on bicycle sharing usage

Using panel regression methods, this paper investigates how the COVID-19 pandemic impacted bicycle sharing system (BSS) ridership in Budapest. In particular, the paper aims to separate the effects of mobility and government restrictions on BSS ridership and analyse whether long-term positive effects are observable in this city. Results indicate that both mobility and government stringency measures significantly and positively affected BSS usage, particularly in residential areas and close to public parks. However, after the first wave of the pandemic passed and government measures were partially lifted, BSS ridership declined in line with the elimination of the restrictions. New users often churned after their first trial, and usage frequency dropped to lower levels than before the pandemic. This indicates that BSS was a valuable transportation mode during a pandemic, but a permanent increase in usage was not observed in Budapest despite a considerable price decrease in bicycle fares. The unsatisfactory experiences with this BSS, primarily due to heavy bike frames and solid rubber tires may be the cause of this. Our results prove the benefits of BSS in mitigating a pandemic but call the attention to the need to improve particular system characteristics that may undermine long-term ridership. These characteristics can be different for every BSS; hence, local market research is required. This limits the generalizability of the results.

Erasmus Staff Mobility in the Building of a European Network: The Case of a Central European University

Globalization now applies to almost all aspects of life, and it also applies to the world of science. Internationalisation and interdisciplinarity are fundamental determinants of modern research and education. The foremost factor of functioning in the international world of science is the mobility of students and scientists. Considering this context, the objective of this study was to analyse the staff mobility for teaching under the Erasmus+ programme at the Wrocław University of Environmental and Life Sciences (UPWr). The research took into account the mobility of staff for teaching (STA) within the period of the academic years from 2009/2010 to 2020/2021. The methodological approach applied in this study is based on the concept of mobility network analysis and mobility flows. The geo-visualization was prepared with the use of a spider diagram. Using this approach, the connections between spatial locations and domains of scientific activity were analysed. The results show that the mobility flow at UPWr rose significantly after the authorities of the university decided to increase the funding for STA, and eventually was slowed down by the outbreak of the COVID-19 pandemic. Moreover, the findings in the geographical aspect show that there were two main regions of destination, which were the Iberian Peninsula and the closest neighbouring countries, where the predominant institutions could be observed. The most mobile group of teachers were the ones representing environment sciences. The STA flow is not reflected in the students’ mobility flow. COVID-19 has enhanced the virtual component of learning, resulting in the strengthening of the blended mobility model.