Temperatures in the Rocky Mountains have risen by a degree or two Celsius across the region over the last century. That might seem modest, but the National Park Service says that in some places invasive species are on the rise, and there’s less water for plants and animals. Swiss bicyclist Florian Reber is documenting these changes as he rides the Continental Divide from Vancouver to New Mexico, blogging and filming a documentary. And he was just in Colorado. We spoke with him by Skype.