Probably nothing is more impressive concerning the underwater world than its colors. Corals, colorful fish and the play of the sun shining through the waves. Divers know what is meant. But - all of this is endangered by climate change. The world's oceans are already warmed up to a depth of two kilometers by a tenth of a degree - this could be devastating for coral reefs and the oxygen content in the ocean. At the water sports fair boot in Düsseldorf, it's not all about climate protection. Because without intact water there can also not be any water sports.