Thomas Weatherburn
The Urban Heat Island in Toronto: Interpreting Mesoclimates through Detrended Kriging and Multiple Linear Regression © 2009
The phenomenon of increases in temperature from rural to urban regions, the urban heat island (UHI) effect, has pressing implications for health, energy and the economy. Such implications are now salient for decisions made by city planners and environmental urban designers. In this paper the mesoclimates of the Toronto region were modelled based on theoretical principles of microclimatology and UHI development for the years 1978, 1992 and 2000 using Environment Canada climate station observations. Multiple analytical procedures were used in response to the low number of temperature observations. Continuous temperature fields, interpolated using detrended Ordinary Kriging and multiple linear regression analysis, have shown the distinct influence of elevation, distance to Lake Ontario, NDVI values and the percentage of urban area on temperature. The explanatory power of the regression models (R2 from 0.766 to 0.609) shows the degree of urbanization in a mesoclimatic context to be a significant determinant of temperature. Further collection of temperature data at the scale necessary to observe micro-variations in temperature within cities could provide useful insights.