The survey has data going back to 1974 and it includes details on hills around Drumochter and Glenshee, as well as some of Scotland’s highest mountains such as Cairn Gorm, Ben Macdui and Braeriach.
Mr Cameron said there was a downward trend in patches.
He told Scotland News: “I am inured to the low numbers now to an extent, but I am old enough to remember when we used to get far more patches of snow.
“It is an unpleasant experience to count so few of them.”
He added: “I believe in 50 to 100 years time patches of snow will be a distant memory.
“Hopefully researchers in the future will be able to look to our research and get a lot of value from it, and probably be shocked to know snow was able to last all year round in Scotland once upon a time.”
