Spatial Heterogeneity of Weather impacts on Cycling Flows within Gothenburg, Sweden - A Geographic Framework for Local Pattern Analysis
Background: In the past decade, the phenomenon of spatial heterogeneity has started to gain traction in studies of cycling and weather. Cycling is usually the mode of transportation that is most affected by inclement weather and the scientific consensus about how weather impacts cycling behaviour on a general scale is for the most part well-established. On a regional scale, weather effects have been found to be more adverse in low-density rural communities, whilst the impact is less severe in more compact cities. However, to this date, little is known about how, and even if weather produces heterogonous cycling patterns on a local city scale. Method: Given the lack of precedent to studies of spatial heterogeneity on a local scale, this study developed and applied a framework to investigate the presence of the phenomenon. The framework consists of two parts. First, a cartographic exploration of correlation coefficients linked to cycle-measurement stations around the city of Gothenburg. Second, a weather sensitivity analysis was conducted to identify if urban areas with similar characteristics was associated with spatial heterogeneity. Properties of the urban environment were quantified with a modified Local Climate Zone system to capture the dominant urban characteristics that surrounds every cycle-measurement station and their corresponding cycleway segment. Results: Findings made in this showed that the impact of the weather indices temperature, sunshine, precipitation and gustiness varies across the city of Gothenburg. The pattern of spatial heterogeneity was especially pronounced in relation to gustiness. Coastal environments characterized by openness were consistently more sensitive to higher wind speeds. The duration of sunshine was also more important to urban areas with a low density. Two precipitation indices were considered, along with the binary occurrence of a precipitation event. The duration of precipitation had the most negative impact on cycle frequencies and the effect was stronger than even the binary occurrence of a precipitation event. Surprisingly, in the densest built environments, cycling appears to be more sensitive to precipitation than areas characterized by openness. Discussion: These results have some important implications for planning authorities. First, weather is not an entirely uncontrollable phenomenon in relation to cycling. It is possible to identify areas that are more affected by certain weather conditions and thus take appropriate action. Second, this study found evidence that spatial heterogeneity exists, but the robustness of the proposed framework needs refining before the results can be regarded as conducive. Conclusions: This study could be used as a way forward for professionals who struggle to find out where they should intervene to empower cycling. The framework proposed in this study can also be used to identify urban environments that are more adversely affected by certain weather conditions without actual measurements of the cycle volume in these areas. Further developments are recommended, but the framework in this study could be a costeffective way of identifying especially weather sensitive areas of the urban environment.