Photo: University of Hamburg / Feuerböther

Students on campus with a bicycle

Cyclists in Hamburg remain surprisingly unaffected by rain and wind, with weather suitable for cycling about 90% of the year. “This means that the weather here is nowhere near as bad as its reputation,” explains Prof. Dr. Felix Ament, who co-authored the study with Dr. Amelie Schmitt.

The team simulated 10,000 bike rides in Hamburg and assessed the meteorological comfort of each individual ride using data on precipitation, wind, and temperature. The results were presented as a traffic light: Green for good cycling conditions, yellow for unsuitable weather and red for uncomfortable or even dangerous weather conditions.

“The traffic lights gave the green light for around two thirds of the journeys,” says meteorologist Amelie Schmitt. The main reason for a red light was mainly the temperature, while precipitation and wind were rarely the deciding factors. “Heat in particular can make cycling very uncomfortable. We found about 12 percent of all simulated tours in the summer months fit this description,” says Schmitt.

When it rained, the researchers from the Center for Earth System Research and Sustainability (CEN) assessed the amount of precipitation in millimeters for every minute of cycling. Short, heavy showers were ranked the same as longer, but lighter, rain. A green rating, allowed for cyclists to be affected by a maximum of 0.1 millimeters of rain. This corresponds to just a few minutes of light drizzle.

“Flexible working hours can help you pick the right time to get to the office by bike when it’s raining,” says meteorologist Felix Ament. “Our measurement data shows that there are usually enough breaks between rain periods in Hamburg and the precipitation cells are small enough. With just one hour of flexibility, you can avoid every second rain shower.”

The results of the study offer approaches to developing new apps that will allow citizens to better adapt to the weather when planning journeys by bike in future.

This current video from the team provides some insights into the research.

Original publication:

Amelie U. Schmitt, Finn Burgemeister, Henning Dorff, Tobias Finn, Akio Hansen, Bastian Kirsch, Ingo Lange, Jule Radtke, Felix Ament: Assessing the weather conditions for urban cyclists by spatially dense measurements with an agent-based approach

Press release as PDF