Abstract：
The use of cars in cities has many negative impacts, including pollution, noise and the use of space. Yet, detecting factors that reduce the use of cars is a serious challenge, particularly across different regions. Here, we model the use of various modes of transport in a city by aggregating Active mobility (A), Public Transport (B) and Cars (C), expressing the modal share of a city by its ABC triplet. Data for nearly 800 cities across 61 countries is used to model car use and its relationship with city size and income. Our findings suggest that with longer distances and the congestion experienced in large cities, Active mobility and journeys by Car are less frequent, but Public Transport is more prominent. Further, income is strongly related to the use of cars. Results show that a city with twice the income has 37% more journeys by Car. Yet, there are significant differences across regions. For cities in Asia, Public Transport contributes to a substantial share of their journeys. For cities in the US, Canada, Australia, and New Zealand, most of their mobility depends on Cars, regardless of city size. In Europe, there are vast heterogeneities in their modal share, from cities with mostly Active mobility (like Utrecht) to cities where Public Transport is crucial (like Paris or London) and cities where more than two out of three of their journeys are by Car (like Rome and Manchester).
摘要：
在城市中使用汽车有许多负面影响，包括污染,噪音和空间的使用。然而，检测减少汽车使用的因素是一个严峻的挑战，尤其是在不同地区。这里,我们通过汇总主动交通(A)，对城市中各种交通方式的使用进行建模。公共交通（B）和汽车（C），用ABC三元组表达城市的模态份额。来自61个国家/地区的近800个城市的数据用于模拟汽车使用及其与城市规模和收入的关系。我们的研究结果表明，随着距离的延长和大城市的拥堵，汽车的主动行动和旅行不太频繁，但公共交通更为突出。Further,收入与汽车的使用密切相关。结果显示，一个收入两倍的城市乘坐汽车的旅行次数增加了37％。然而，各地区之间存在显著差异。对于亚洲的城市来说，公共交通为他们的旅程贡献了很大一部分。对于美国的城市来说，加拿大,澳大利亚,新西兰,他们的大部分机动性取决于汽车，无论城市大小。在欧洲,它们的模态份额有很大的异质性，从主要是主动交通的城市（如乌得勒支）到公共交通至关重要的城市（如巴黎或伦敦），以及其中超过三分之二的旅程是乘车的城市（如罗马和曼彻斯特）。
