John Ross Mackay, OC FRSC (偕約翰, December 31, 1915 – October 28, 2014) was a Canadian geographer. He is most noted for his explorations of permafrost phenomena in the western Canadian Arctic. His 40 plus years of study has enabled the building of pipeline operations and petroleum explorations in areas of frozen ground. The Royal Society of Canada stated the following when Mackay was awarded the Willet G. Miller Medal in 1975: