The thermal imaging technique relies on the usage of infrared signal to detect the temperature field.Using temperature as a flow tracer,thermography is used to investigate the scalar transport in the shallow-water wake generated by an emergent circular cylinder.Thermal imaging is demonstrated to be a good quantitative flow visualization technique for studying turbulent mixing phenomena in shallow waters.A key advantage of the thermal imaging method over other scalar measurement techniques,such as the Laser Induced Fluorescence(LIF)and Planar Concentration Analysis(PCA)methods,is that it involves a very simple experimental setup.The dispersion characteristics captured with this technique are found to be similar to past studies with traditional measurement techniques.