By DREW COSTLEY and SETH BORENSTEIN
ST. HELENA ISLAND, S.C. (AP) — In some parts of the U.S., the risks from climate change have intensified enough to raise a startling question: Should some populated places simply be abandoned to nature? One strategy that is gaining traction is so-called managed retreat, which is the planned relocation of vulnerable communities. Forms of managed retreat have existed in the U.S. since at least 1989, when the Federal Emergency Management Agency began buying properties in flood-prone areas. Parts of Louisiana, Wisconsin and Illinois have used planned relocation to try to save communities from flooding and rising seas. Florida, California and New York could someday need to use the strategy too.