UK satellites track global water flows to strengthen climate modelling and industrial risk planning

TWO UK-built satellites have been launched into orbit to improve monitoring of the planet’s water cycle – data that chemical and process engineers rely on for climate-risk assessments, emissions modelling and the design of resilient infrastructure.

Launched from California on a SpaceX rocket, HydroGNSS-1 and HydroGNSS-2 were built by Surrey Satellite Technology (SSTL) in Guildford and supported by £26m of UK Space Agency funding.

The mission aims to produce low-cost, rapidly delivered Earth-observation data that can feed directly into climate models and environmental simulation tools used across the process industries.

The satellites will be used to collect data for climate science and environmental modelling as part of the Scout programme’s wider effort for more efficient weather forecasting, flood prediction and agricultural planning.

Accurate forecasting of soil moisture, flooding, freeze–thaw behaviour and biomass levels increasingly underpins decision-making in sectors such as water treatment, energy, agriculture and chemicals manufacturing.

Sensing technology

The satellites fly in orbits 180° apart and use GNSS reflectometry, a technique that measures GPS and Galileo signals bounced off Earth’s surface. This enables the measurement of key hydrological variables even through thick cloud or forest cover – conditions that often obstruct traditional sensors.

SSTL’s managing director Andrew Cawthorne said: “This mission is a fantastic example of how the UK, working through ESA and with support from the UK Space Agency, is delivering world-class climate science from space.

“HydroGNSS represents SSTL’s 75th and 76th satellites, launched in our 40th anniversary year, and showcases the strength and innovation of the UK’s space industry at the heart of Europe’s environmental monitoring efforts.”

Scout missions

HydroGNSS is the first in ESA’s Scout series, designed to produce focused science missions costing under €35m (US$41m) and developed in under three years.

Other missions in the programme include NanoMagSat, which will track Earth’s magnetic field, and Tango, which will monitor methane, CO2 and nitrogen dioxide from industrial sites worldwide.

Simonetta Cheli, director of Earth Observation Programmes at ESA, said the launch “marks an important milestone for this new family of rapid, low-cost Earth observation missions”.