“NEW YORK CITY’S HEAT ISLAND. Surface air temperatures elevated by at least 1°C have been observed in New York City for more than a century (Rosenthal et al. 2003; Gaffin et al. 2008), and the heat island signal, measured as the difference between the urban core and the surrounding rural surface air temperature readings taken at National Weather Service (NWS) stations, averages ~4°C on summer nights (Kirkpatrick and Shulman 1987; Gedzelman et al. 2003; Gaffin et al. 2008). The greatest temperature differences typically are sustained between midnight and 0500 Eastern Standard Time (EST; Gaffin et al.
2008).
Surface air temperature data from weather stations both in and around New York City were mapped to show the heat island at 0600 EST 14 August 2002, the early morning of what would become one of the
hottest heat-wave days that summer (Fig. 1). Within the city, the three NWS stations are located in Central Park, and at LaGuardia and John F. Kennedy airports. To improve coverage of New York City, data were
obtained from the WeatherBug network of automated private stations (AWS; online at www.aws. com/aws_2005/default.asp).4 Surface air temperature readings from these stations show that the city was several degrees warmer than the suburbs, and up to 8°C warmer than rural areas within 100 km of the city, with conditions that had been sustained
throughout the previous night.”
