New Scientist: The majestic old trees of the western US are disappearing twice as fast as they were three decades ago, and climate change is most likely to blame, say scientists. Philip van Mantgem of the US Geological Survey and colleagues collected data from 76 plots on the west coast — from California up to British Columbia, Canada — and in Idaho, Arizona and Colorado. These are plots without any direct human management, so any tree loss is not due to logging. The team focused on old …