The Analog City Study: What if the 2003 European Heat Wave Occurred in a Major U.S City?

Europe experienced an unprecedented excessive heat event (EHE) in 2003. This raises the question, “What if a similar EHE were experienced in U.S. cities?” This study uses a revised synoptic meteorological method to develop analogs to the 2003 European EHE for five U.S. cities: Detroit, New York, Philadelphia, St. Louis, and Washington, D.C., and then calculates the potential excess mortality the analog could produce. The analogs captured the 2003 EHE's characteristics by developing a daily air mass calendar for Paris June through August, 2003. The daily deviation from long-term averages in meteorological variables were calculated and expressed as a multiple of the long-term average's standard deviation. Excess mortality was calculated using existing synoptic air-mass algorithms. The analog EHEs break all-time records for maximum and high minimum temperatures in all cities. Excess mortality in the analogs is 3 to 12 times long-term results previously calculated for EHEs. These results help define a plausible scale of EHE-attributable mortality using a worst-case scenario based on observed data. In addition to providing potentially valuable information for public health planning, the analog's meteorological datasets could be used for a wide range of additional reliability or sensitivity analyses.