MARSHALL ISLANDS. ARNO. Arno is one of the idyllic palm-fringed atolls which make up the Marshall Islands. Here the toppled coconut palms show how sea level rise is nibbling away at the already tiny islands. Often less than 50 metres (55 yards) from lagoon to the open ocean. The coconut palms' survival is essential because they hold together the soil and make up the major agricultural crop of the islands. 2004.