A STUDY OF PHILADELPHIA’S URBAN HEAT ISLAND INCLUDING TEMPERATURE MAPPING AND 3-MONTH SEASONAL ANALYSIS

The Philadelphia Metropolitan Area has undergone rapid and extensive urban growth since the 1940s (Figure 1, 2a, 2b). Data from the Pennsylvania Mesonet, New Jersey Weather Mesonet and Delaware Environmental Observation System were used along with McIDAS-V software to generate isotherm maps, thus revealing Philadelphia’s UHI. To obtain quantitative values for Philadelphia’s UHI strength, an urban-rural temperature difference (ΔT_U-R) was established. Under favorable (but not the most optimal) conditions for UHI development (Case 1: July 9, 2012 from 0100Z-0800Z), Philadelphia’s UHI exhibited an average ΔT_U-R of 3.5 °C with parts as strong as 4.3 °C. Over a seasonal basis (Case 2: August 1, 2012-October 31, 2012 at 0900Z), Philadelphia’s UHI exhibited an average ΔT_U-R of 2.2 °C, with parts as strong as 2.8 °C.