where, AT is the temperature rise above ambient(degrees Celsius), 3.9 (in present units) is a proportionality constant derived empirically from field measurements,I is frontal fire intensity (kilowatts per meter),and h is the height above ground (metres). For example,with the ambient temperatures in Table 1 of Smith and James (1978) and the computed frontal fire intensities,temperatures at 5 m above the surface probably approached 61, 54, 63, and 50°C, respectively.