Inhabit: A prominent climate scientist has declared a "global climate emergency" after observing the jet stream in the Northern Hemisphere crossing the equator and mixing with the jet stream in the Southern Hemisphere. Paul Beckwith, a geography professor at the University of Ottawa, wrote in a blog post that this behavior is new and "indicates that climate system mayhem is ongoing." If the merging of the jet streams continues, it could disrupt the seasons, threatening the food supply chain and causing "massive...