ECV Products and Requirements for River Discharge
These products and requirements reflect the Implementation Plan 2016 (GCOS-200). GCOS is reviewing and will update the requirements until 2022. More information on: gcos.wmo.int.
| PRODUCT | DEFINITION | FREQUENCY | RESOLUTION | REQUIRED MEASUREMENT UNCERTAINTY | STABILITY | STANDARDS/ REFERENCES |
| River Discharge | Volume of water flowing through a river (or channel) cross-section per unit time | Daily | Per river | 10 % (relative) | ISO/TC 113: WMO (2010) WMO (2008a) WMO (2009) | |
| Water Level | Elevation of the free-water surface of a body of water relative to a datum level | Daily | 100m | 10 cm | 1 cm/yr | ISO/TC 113: WMO (2010) WMO (2008a) WMO (2009) |
| Flow Velocity | Vector indicating the speed and direction, at a point, of a moving liquid | Few times per year for station calibration | Per river | 10 % (relative) | ISO/TC 113: WMO (2010) WMO (2008a) WMO (2009) | |
| Cross-Section | Section perpendicular to the main direction of flow bounded by the free surface and wetted perimeter of the stream or channel (ISO 772) | Few times per year for station calibration | Per river | 10 % (relative) | ISO/TC 113: WMO (2010) WMO (2008a) WMO (2009) |
