>>13942819This happens when the desert exists before the sea. All the dry sand sucks the moisture out of the water, leaving it salty. This process is called "Salinatunfication". In turn the salty water leaves deposits of crystalline salt along the shore, making it very dry, and so perpetuates the cycle. The first scientist to properly investigate this process, Dr John James of the University of Arizona, also described a reverse process which can happen in some circumstances, whereby lakes of fresh water can be formed by deserts which themselves then turn into lush tropical rain forests. This reverse process became known as "Reverse Salinatunfication" and has become the subject of intense study in recent years by researchers looking for cost effective ways to green desert regions around the world.