Source: Pascal Brackman
It is not a coincidence that the dune area of Psili Ammos is located on the south side of the long beach of Psili Ammos. The most prevailing wind on this island is coming from the north. That means that the sand of of Psili Ammos is blown to the south, and piled up on that side. The reason why there are mainly northerly winds here is that the air above the desert of Egypt and Libya (south of here) is being heated up and as such ascents. That results in a low pressure area. As a result, air from the north which is mainly a high pressure area, is sucked into that low pressure area. Who would realize that such a macro structure has an effect on the local beach of Psili Ammos.