Provides continuously updated data on the state of the world's oceans, maps, development trends and threats to human heath from the deteriorating marine environment - such as overfishing and pollution that endangers marine biodiversity, coastal habitats, and the global climate.
In association with Environment Canada, the United Nations also maintains the GEMS/WATER site detailing global freshwater quality issues, featuring information on 82 major watersheds of the world. The World Ocean Atlas from the US National Oceanographic Data Centre provides maps of the world's oceans showing variables such as water temperature, salinity, oxygen,nutrients, chlorophyll, and zooplankton.