Hot in Baltimore: Urban Form's Impact on Fine-scale Temperature Differences

Heatwaves, the deadliest form of climate hazard, are amplified in cities because of urban-rural temperature differences, also know as the urban heat island effect. In Baltimore, the observed downtown-rural temperature difference, as measured by NOAA stations, can reach 5°C. Underserved, low-income neighborhoods are almost entirely covered by impervious surfaces like concrete but lack trees and parks, so their urban-rural temperature difference is expected to exceed the reported one. However, that difference is not well quantified because these areas lack weather station coverage. Additionally, high resolution satellite imagery shows only land surface temperatures (inadequate for policy and health interventions) and may miss severe heat events. To remedy this, a low-cost monitoring network was installed in East Baltimore over summer 2015 aiming to characterize spatial and temporal variability as well as examine how the heat excess varies during heat events. Results show that low cost sensors can accurately capture temperature variability and help attribute temperature anomalies to local features such as land cover, building density and tree canopy.