Climate change, weather and road deaths

Area of Science:

• Environmental Science
• Epidemiology
• Transportation Safety

Background:

• A 7% increase in US road deaths per capita in 2015 ended a 35-year declining trend.
• The influence of weather on this trend reversal requires investigation.

Purpose of the Study:

• To test the hypothesis that weather, particularly temperature, influenced the 2015 increase in US road deaths.
• To quantify the impact of temperature and precipitation on driving behavior and traffic fatalities.

Main Methods:

• Linear regression was used to assess the effect of temperature and precipitation on miles driven per capita in US urban areas (2010).
• Risk per person exposed to specific temperatures was calculated by matching death records with temperature data.
• Logistic regression analyzed temperature, precipitation, and 2014 risk factors to project 2015 deaths in the 100 most populous US counties.

Main Results:

• Analysis indicated a correlation between increased temperatures and changes in driving patterns.
• Projected 2015 deaths, adjusted for temperature increases, showed a significant difference from actual fatalities.
• The study estimated the number of deaths attributable to the temperature rise.

Conclusions:

• Weather, specifically elevated temperatures, is a significant factor contributing to the reversal of the long-term downward trend in US road safety.
• Understanding the impact of weather on driving behavior is crucial for developing effective traffic safety interventions.
• Further research should explore the complex interplay between weather, human behavior, and road safety outcomes.