Guardian: With barely five months until make-or-break climate talks in Copenhagen, where the world will attempt to agree a new treaty on climate change, how significant are the G8 announcements? Headline writers have drooled over the “historic” agreement to limit the global temperature rise to 2C, to cut world emissions 50% by 2050, and for the G8 to reduce its own pollution 80% by that date. The numbers may sound reassuringly low, large and colossal, respectively, but there is …