Report is here: https://rosap.ntl.bts.gov/view/dot/85611

Our final report is out. By Stanier, Arinze Okoye, Sheng (Jerry) Wang, and Addi O'Grady. Not peer-reviewed, but (in our opinion) a valuable contribution that can guide future work.

Executive summary: Extreme heat events have impacts on road transit systems. The primary impact is through heat stress on motorists, construction and maintenance crews, and public safety personnel. Heat stress effects are strongest on sensitive subgroups, including infants, children, the elderly, pregnant women, and those with preexisting medical conditions. Heat is associated with decreased driver performance and increased emergency service calls and can interfere with road surface integrity and vehicle operation. Extreme heat also poses challenges to transport of animals in the region. Extreme heat increases transit system pollutant emissions in multiple ways, including increased particle emissions from tires and road wear, increased organic compound emissions from off-gassing asphalt and plastics, and increased fuel use. Pavement and
near-road air temperatures and heat indices (which can include humidity, or humidity, wind and solar radiation) can be estimated throughout the Midwest using a combination of in situ measurements and estimated environmental parameters from public databases. Downscaled global climate models indicate that the intensity and number of extreme events will increase in coming decades. Historical data and future projections indicate that daytime temperature-humidity heat indices will increase more rapidly than temperature alone. Satellite remote sensing, combining high spatial resolution visible imagery with lower spatial resolution multispectral imagery, can estimate road surface temperatures at seasonal average timescales.