Undoubtedly, climate change and its mitigation have emerged as main topics in public discourse. While accessibility planning is recognized for supporting sustainable urban and transport development in general, the specific challenge of reducing transport-related greenhouse gas emissions has rarely been directly addressed. Traditionally, accessibility is operationalized in line with the user perception of the transport system. Travel-time-based measures are considered to be closely linked with travel behavior theory, whereas CO2 emissions are not necessarily a major determinant of travel decisions. Given the changed prioritization of objectives, additional emphasis should be placed on the environmental costs of travel rather than solely the user costs. Accessibility analysis could account for this shift in perspectives by using CO2 emissions instead of travel time in the underlying cost function. While losing predictive power in terms of travel behavior compared to other implementations of accessibility, carbon-based accessibility analysis enables a normative understanding of travel behavior as it ought to be. An application in the Munich region visualizes the differences between travel-time-based and carbon-based accessibility by location, transport mode, and specification of the accessibility measure. The emerging accessibility landscapes illustrate the ability of carbon-based accessibility analysis to provide new insights into land use and transport systems from a different perspective. Based on this exercise, several use cases in the context of low-carbon mobility planning are discussed and pathways to further develop and test the method in cooperation with decision-makers are outlined.

中文翻译：

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转变观点：基于旅行时间和基于碳的可达性景观的比较

毫无疑问，气候变化及其减缓已成为公众讨论的主要话题。虽然无障碍规划被普遍认为可以支持可持续的城市和交通发展，但减少与交通有关的温室气体排放的具体挑战很少得到直接解决。传统上，可访问性是根据用户对交通系统的看法来操作的。基于旅行时间的措施被认为与旅行行为理论密切相关，而二氧化碳排放不一定是旅行决策的主要决定因素。鉴于目标的优先顺序发生了变化，应更加重视旅行的环境成本，而不仅仅是用户成本。可访问性分析可以通过在潜在成本函数中使用二氧化碳排放量而不是旅行时间来解释这种观点的转变。与其他可访问性实施相比，虽然在旅行行为方面失去了预测能力，但基于碳的可访问性分析使人们能够对旅行行为进行规范的理解，因为它应该是。慕尼黑地区的一个应用程序通过位置、交通方式和可达性度量的规范来可视化基于旅行时间和基于碳的可达性之间的差异。新兴的可达性景观说明了基于碳的可达性分析能够从不同的角度为土地利用和交通系统提供新的见解。基于这个练习，