signal than the city of Phoenix, but only because of the variation of land cover from built to forested, relative to the homogenous bare soil land cover in Phoenix. While Phoenix is hotter in absolute terms, the relative temperature difference between urban and non-urban Chicago is far greater.
Lastly, we assessed the land cover distribution of each location using the National land Cover Dataset (NLCD), shown in Figure 2, to see if variation in cover percentages were correlated with the urban heat distribution.
Figure 2. Land cover distribution in 2011 for Lexington, Kentucky according to the USGS National Land Cover Dataset (NLCD). Impervious areas correlate with increased temperatures.
We can say that the magnitude of urban heat island is different across locations because of the physical differences in land cover composition. As proof we see the distribution of the land cover follow the same spatial patterns as the distribution of the increased temperatures. For example, the highest temperatures were in the land covers dominated by high-density impervious developments while the lowest temperatures were in the forestland covers of the surrounding