>>1803069In cases where you're getting blasted by extreme UV radiation for extended amounts of time it is mandatory to cover your skin. Sunscreen is good for half a day at the beach but if you're touring ALL day, every day, sweating there is no other choice.
It sucks having to wear long sleeves in such hot weather but if you're careful about what you select (see
>>1803017) it's alright.
May I also recommend hitting up a thrift store and, IF you get really lucky), find long sleeve button up natural silk shirts. They are absolutely 100% alien technology. So light and breezy and they never stink no matter how many gallons of sweat you pour into them.