Surface sensible heat flux (Qh) is strongly conditioned by surface temperature. One part of my research is looking at how well urban surface heat flux can be modelled and how remotely-observed surface temperature can best be used in estimating Qh.

Modelling of the sensible heat flux incorporates the source area concept (see Schmid, 1994) which estimates the area most likely contributing to the heat flux measurement. With source area estimates calculated, we can then assess the microscale variability of surface temperature contributing to the measurement.

For a full description of the project and results see Voogt and Grimmond (2000). Further work has been carried out using tower observations over residential areas in Tokyo, Japan, Vancouver, B.C, and Marseille France (ESCOMPTE project). Graduate student research opportunities are available to work on these projects. 

Figure 1 illustrates the process of overlaying a source area on a composite thermal image.   The colour scale indicates the source area weighting: higher weights (higher contribution to the flux) are yellow and white, lower weights are red and black.

Figure 1. Composite thermal image overlain with a source area function. Tower position is to the right of the source area with the wind coming from upwind of the source area (WSW in this case). From Voogt and Grimmond (1998).