It looks a little strange from the air, rolling dunes topped with tufted grasses leading to desert-like landscapes where angular outcrops stand above dry, waterless canyons, dunes which form the hinterland to miles of empty golden beach. There’s not a single building to be seen until just before the wheels of the aeroplane touch down on the tarmac – and even then, it’s an airport terminal which looks more like a sand castle than a transport hub. The island of Boa Vista fights two perpetual battles with nature. One, Sahara sand from continental Africa blows constantly across the island, shifting dunes from east to west and regularly forming damaging sand…