WMO Hydrological Observing System

WMO Hydrological Observing System

The WMO Hydrological Observing System (WHOS) is  a portal to the online holdings of National Hydrological Services (NHS) around the world that publish their historical observation and/or real-time data without restrictions or cost. It represents the hydrological component of the WMO Integrated Global Observing System (WIGOS).
Important Notes: WHOS is being developed and implemented in phases.  The map interface appearing above is a provisional product designed for demonstration and testing in preparation for a review of the WHOS concept at the 15th Session of the Commission for Hydrology (CHy-15) in December 2016.  A full WHOS implementation is subject to approval by CHy-15.

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As the global population grows and the demand for water increases, it is critical to effectively and sustainably manage our limited water resources. To do so, we need to know where they are, in what quantity and quality, how variable they are, and how they will evolve  in the foreseeable future.

Commission for Hydrology (CHy)

The Commission for Hydrology (CHy) addresses basic hydrological observation networks, water resources assessment, flood forecasting and warning, flood and drought management and adaptability to climate variability and change and promotes the exchange of technology and capacity building.