The map layer shows the 405 largest river basin areas in the world classified by the number of riparian states.
Example: How to read the map:
The catchment area of the River Rhine extends across nine states (Germany, Austria, Italy, Switzerland, France, Belgium, Luxembourg, the Netherlands, Liechtenstein) and totals 190,522km2.
The Global Runoff Data Centre (GRDC)
The Global Runoff Data Centre (GRDC) was founded in Koblenz by the German Federal Institute of Hydrology (BfG) in 1998. Under the supervision of the World Meteorological Organization (WMO), the Centre promotes the exchange of hydrological data and information at a global level and supports the UN’s hydrological and climate-related programmes. In this respect, the GRDC consolidates data from more than 9,000 gauging stations in a central database and makes the results available at no charge for non-commercial purposes. Furthermore, global data sets on the spatial dimension of the largest river basins in the world are made available and kept up to date.