This article was originally published by The Guardian and is reproduced here as part of the Climate Desk collaboration. The Lake Borgne Surge Barrier, which was built after Hurricane Katrina to protect New Orleans from floods. U.S. Army Corps of Engineers Rising seas could render New Orleans uninhabitable before the end of this century, according to a new paper calling for a managed retreat from the city. The process of relocating people from New Orleans should start immediately, as the city has reached a “point of no return” that will see it surrounded by the ocean within decades due to the climate crisis, a stark new study has concluded.…