Living in the Arizona desert, clouds are a rare occurrence. But in the Andean highlands, they are everything. The cloud forest (bosque nublado) that dominates these mountains can change its character rapidly, and so imposes its rhythms on its inhabitants. The first thing to understand is where cloud forest comes from. Clouds form as moist…

A field campaign is not very different than a space launch. After seven weeks of fieldwork in Peru, I’ve returned from our expedition and have been contemplating the long journeys we made, laden with supplies and scientists. Like a space mission, we aim for inhospitable destinations in far-away places. The steep slopes of the cloud…