Safe cycling in winter: Results of a case study on the role of de-icing in the city of Hamburg, Germany.

INTRODUCTION: In parts of Europe and North America, cycling volumes decrease in winter due to a reduction in subjective safety. To counter this, high-quality winter maintenance is required on cycle paths. At the moment, grit and sodium chloride are considered state-of-the-art gritting/de-icing materials in Germany. However, grit has to be removed after winter because it poses a serious injury risk on dry streets, and, in various German cities, using sodium chloride is prohibited on segregated bike paths due to the harmful impact on surrounding trees. Therefore, there is a need for alternative gritting/de-icing materials. METHOD: We used a mixed-methods approach consisting of qualitative and quantitative surveys together with laboratory investigations and a life cycle assessment to find suitable alternatives to sodium chloride and grit for use on segregated bike paths, and tested four de-icing materials (sodium chloride as a reference, sodium formate, calcium magnesium acetate or CMA, and potassium acetate) at two sites in Hamburg, Germany. The tests were accompanied by on-site cyclist surveys. RESULTS: The results show that the use of alternative (non-sodium chloride) de-icing materials either reduces or eliminates negative impacts on the environment at a local level, for example on trees along the cycle path. However, this reduction goes hand in hand with increasing negative environmental impacts at a global level due to higher overall emissions associated with the tested alternative de-icing materials. Regarding cyclists' safety, sodium formate was the only de-icing material which delivered comparable results to sodium chloride and should therefore be tested in extended conditions. CONCLUSIONS: Further research is needed on the large-scale application of the investigated de-icing agents on cycle paths in different cities, along with a survey of a larger number of cyclists. A final evaluation of the environmental aspects can only be made when the supply and production conditions for large-scale use are clear. PRACTICAL APPLICATIONS: Basically there are two options for the practical application of de-icing materials: The usage of the costlier alternatives with better properties at a local level in the hope of fast development towards a better global GHG footprint in their manufacturing processes, or sticking to the use of grit and sodium chloride (where it is possible) while committing to improving clean-up after the snow and ice melt to prevent unsafe road conditions in spring.

Impact of SARS-CoV-2 on the mobility behaviour in Germany.

Background: The COVID-19 pandemic and the measures taken to combat it led to severe constraints for various areas of life, including mobility. To study the effects of this disruptive situation on the mobility behaviour of entire subgroups, and how they shape their mobility in reaction to the special circumstances, can help to better understand, how people react to external changes. Methodology: Aim of the study presented in this article was to investigate to what extent, how and in what areas mobility behaviour has changed during the outbreak of SARS-CoV-2 in Germany. In addition, a focus was put on the comparison of federal states with and without lockdown in order to investigate a possible contribution of this measure to changes in mobility. We asked respondents via an online survey about their trip purposes and trip frequency, their choice of transport mode and the reasons for choosing it in the context of the COVID-19 crisis. For the analyses presented in this paper, we used the data of 4157survey participants (2512 without lockdown, 1645 with lockdown). Results: The data confirmed a profound impact on the mobility behaviour with a shift away from public transport and increases in car usage, walking and cycling. Comparisons of federal states with and without lockdown revealed only isolated differences. It seems that, even if the lockdown had some minor effects, its role in the observed behavioural changes was minimal.

Are you an ambitious cyclist? Results of the cyclist profile questionnaire in Germany.

Objective: A number of studies have already grouped cyclists according to different aspects of their mobility behavior. This could be used e.g., to improve the bicycle infrastructure planning, to detect critical spots and, to reduce obstacles for cycling. This wide, preexisting, range of cyclist typologies usually concentrates on one or two influence factors and differs, content-wise, in both factors used, as well as, methodically. Based on existing cyclist typologies we extracted all possible influence factors to integrate them in one single questionnaire. The objective of this study, using an empirical, based approach, is to compare this typology of cyclists with existing ones, integrating all known influence factors of recent studies.Methods: To address these issues, we conducted a Germany-wide online survey on cycling behavior, covering all relevant aspects we derived from both literature and especially, former cyclist typology studies including: social factors; the impact of environmental, individual; and route factors; as well as motives. The main goal was to identify distinct types of cyclists, and describe them as detailed as possible. The heterogeneous sample included a total of 10,294 responses.Results: Using factor and cluster analyses, a multidimensional typology with four groups of cyclists was derived which were interpreted as: ambitious, functional, pragmatic, and passionate cyclists. In addition, socio-economic factors, cyclist's motivation, and crash history were analyzed.Conclusion: The results produced by grouping different characteristics of cyclists can lead to policy recommendations or communal bicycle traffic planning. Policy planners can estimate reactions of the different types on interventions and adjust their decisions which can serve to support already passionate cyclists or, encourage normally under-represented infrequent cyclists to cycle more. The extent of perceived safety plays here an important role in the classification, e.g., the handling of high-risk areas for crashes.