I usually joke that here in Scotland people go out sunbathing when the temperature goes over 10C for the first time - sure enough at the end of March I saw a couple walking up from Princes Street Gardens in shorts, t-shirt and flip-flops - the temperature: 11C
Just got back from a semester in Glasgow, can confirm. As someone from the southern US though, I can't blame them. You have to take advantage of any sun you can get.
Although the combination of strong sunlight and your typical peely-wally Scot is often not a happy one.
We get three days a year to get our annual Vitamin D allowance, it's good sense!
Must be a universal phenomenon. We have a similar thing in Chicago.