NASA will launch the SpaceX Falcon 9 rocket, which has been chosen as the vehicle for SWOT's launch. The SWOT satellite observatory is being jointly built by NASA and France's Centre National D'√Čtudes Spatiales (CNES).

SWOT-UK is centred on the Bristol Channel and River Severn, and will examine challenging environmental questions about processes and interactions at coastal/estuarine/land interfaces and their influence on coastal hazards and inland flooding.

Surface Water and Ocean Topography UK (SWOT-UK)


The UK Space Agency invested in SWOT jointly with the US NASA, French CNES and Canadian Space Agency to enable the implementation and launch of this mission. SWOT will observe major lakes, rivers and wetlands while detecting ocean features with unprecedented resolution. SWOT data will provide critical information that is needed to assess water resources on land, track regional sea level changes, monitor coastal processes, and observe small-scale ocean currents and eddies.

  • Project aims

    Provide high-resolution data on the transport of heat and carbon by the Earth's ocean.

    Map ocean currents to benefit shipping and other marine activities.

    Support coastal operations affected by tides, currents, storm surges, sediment transport, and water quality issues.

    Help better manage fishing resources by producing improved data on properties of the ocean.

  • Data sharing

    The objectives of SWOT-UK are to assemble a large dataset of quality-controlled< ground-truth and satellite data of water level, slope and river discharge over the Bristol Channel/River Severn region.

    To carry out a targeted campaign of airborne and shipborne surveys during the SWOT 90-days daily repeat cal-val mission phase to complement existing observations.

    To represent the UK within the international SWOT Science Team, interact with SWOT and the UKSA, and engage with key flood forecasting and coastal management stakeholders and the wider UK community to disseminate findings and quality-controlled datasets.

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Mission Orbit - "fast-sampling" phase with a 1-day repeat orbit at an altitude of 857 km (532.5 mi).

The first 90 days of the SWOT science mission will be flown in a "fast-sampling" phase that revisits specific areas once per day. The next phase will have a 21-day repeat orbit to balance global coverage and frequent sampling. SWOT's 120-km-wide (~75-mi-wide) swath will result in overlapping measurements over most of the globe with an average revisit time of 11 days.

More about the Mission