We examine the reasons why a US locality would voluntarily commit to the Cities for Climate Protection (CCP) campaign. Using geographic information systems analytic techniques, we map and measure a locality's vulnerability to climate-change impacts at the county level of spatial precision. We analyze multiple measures of climate-change vulnerability, including expected temperature change, extreme weather events, and coastal proximity, as well as economic variables, demographic variables, and civic-participation variables that constitute a locality's socioeconomic capacity to commit to costly climate-change policy initiatives. Bivariate and logistic regression results indicate that CCP-committed localities are quantitatively different to noncommitted localities on both climate-change risk and socioeconomic-capacity dimensions. On vulnerability measures, the odds of CCP-campaign participation increase significantly with the number of people killed and injured by extreme weather events, projected temperature change, and coastal proximity. On socioeconomic-capacity measures, the odds of CCP-campaign involvement increase with the percentage of citizens that vote Democrat and recycle, as well as the number of nonprofit organizations with an environment focus. The odds decrease in a county area as the percentage of the labor force employed in carbon-intensive industries increases.
The Flint Water Crisis (FWC) is divisible into four phases of child water-lead exposure risk: Phase A) before the switch in water source to the Flint River (our baseline); Phase B) after the switch in water source, but before boil water advisories; Phase C) after boil water advisories, but before the switch back to the baseline water source of the Detroit Water and Sewerage Department (DWSD); and Phase D) after the switch back to DWSD. The objective of this work is to estimate water-lead attributable movements in child blood lead levels (BLLs) that correspond with the four phases in the FWC. With over 21,000 geo-referenced and time-stamped blood lead samples from children in Genesee County drawn from January 01, 2013 to July 19, 2016, we develop a series of quasi-experimental models to identify the causal effect of water-lead exposure on child BLLs in Flint. We find that the switch in water source (transitioning from phase A to B) caused mean BLLs to increase by about 0.5μg/dL, and increased the likelihood of a child presenting with a BLL ≥ 5μg/dL by a factor of 1.91-3.50, implying an additional 561 children exceeding 5μg/dL. We conservatively estimate cohort social costs (through lost earnings alone) of this increase in water-lead exposed children at $65 million, contrasted with expected annual savings of $2 million from switching water source. On the switch from Phase B to C, we find BLLs decreased about 50% from their initial rise following boil water advisories and subsequent water avoidance behaviors by households. Finally, the return to the baseline source water (Phase D) returned child BLLs to pre-FWC levels further implicating water-lead exposure as a causal source of child BLLs throughout the FWC.