From Frank Rossi, PhD, Cornell University, in his “ShortCutt” blog last month:

Several images have been circulated on Twitter showing a handheld infra-red thermometer that reveal the disparity among pavement, natural turf and synthetic infilled turf on an 85F clear day. The pavement is 115F, the natural turf 98F and the synthetic turf at 158F. Of course, this is the kind of information turf managers should be providing the users of the turf, recognizing there are not many options. This recent observation supports much of the research that has been conducted on surface heating. Mitigating these temperatures is not easy nor is it long lasting. Some have suggested a new type of infill “cool fill” as it is often referred to reduce surface heating. Others recommend irrigating the surface to reduce temperatures. The Penn State Center for Sports Surface Research has been evaluating these issues over the last several years and has concluded that there are different infill materials that do heat less but for practical purposes still warm above 135F as compared to 145F without the cool fill. Second, irrigating synthetic turf for cooling provides an immediate and short-lived benefit that mitigates the surface temperature for 15-30 minutes before it returns to its pre-wet state. It is best to offer athletes natural turf in the current warm weather conditions, as there remains no solid solution for high heat stress conditions created on synthetic turf fields.

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