For many many years now I have worn long sleeves when out in the sun. This is a habit I picked up during my military service, and I continued the practice when I worked in agriculture.
I am firm believer that long sleeves keeps the body cooler by 1) offering sun protection and 2) maintaining a sheen of cooling sweat, that does not dry.
The Outside article caused me to think twice about this long-sleeve-cooling theory because of a reference to sweat evaporation.
I researched the topic a bit, and came across the following article, reinforcing the long-sleeve-cooling theory.
I post it here as another strategy for heat management (yes, I know this blog is sponsored by a clothing manufacturer, with an interest in selling long sleeve summer shirts):
You may be surprised by the unsung features.
blog.coolibar.com