New fleet of advanced robotic floats to understand ocean health

A dark ocean surface littered with ice, an inhospitable and remote location

The ocean plays a vital role in sustaining life on Earth, regulating our climate and providing us with living resources, such as food. A new fleet of advanced robotic floats will provide data to understand the status of the ocean environment and its resources today, and for years to come.

Researchers will be able to gain new insights into how the ocean and climate are changing, and for improving forecasts for planning, resource management, policy development and restoring the health of our oceans.

This month the Natural Environment Research Council and the National Oceanography Centre (NOC) announced an investment of £3.7 million to begin building the UK Atlantic Sector BGC Argo Network (ASBAN-UK). The NOC will deploy 30 Biogeochemical (BGC) Argo profiling floats in the Atlantic Ocean over the next three years as part of the UK Argo programme. Each float will be equipped with sensors to measure pressure, temperature, salt content, pH (ocean acidity), oxygen, nitrate (a nutrient), chlorophyll, particles suspended in the water, and light levels. They will collect observations between the surface and a depth of 2000m, drifting freely around the Atlantic Ocean and operating continuously for about five years.

Data from the floats will allow scientists to address fundamental questions about the role of the ocean in absorbing human carbon emissions, and processes responsible for decreasing levels of oxygen in the global ocean.

Professor Penny Holliday, NOC’s Associate Head of Marine Physics and Ocean Climate, said “Whilst scientists have been able to collect information about ocean health through research ship expeditions, these only cover a tiny fraction of the area of the ocean and short snapshots in time. The use of BGC Argo floats is an innovative low-carbon and low-cost approach to greatly expand the amount of information available for users. The floats will cover much wider areas and measure throughout all seasons including winter storms.”

The floats will make a substantial contribution to the Biogeochemical mission of the international Argo ocean observing network, providing unprecedented resolution and coverage, and forming a key component of the Global Ocean Observing System (GOOS). By relaying their data to global databases in near real-time, the floats will reduce uncertainty in predictions of changes in ocean climate and health for coming decades.

Dr Brian King, NOC senior researcher in marine physics and ocean climate, said “All of the data collected by the floats will be available freely and without restriction to researchers and students, policymakers, resource managers, and others. The NOC’s British Oceanographic Data Centre (BODC) will provide this data in near-real time through the Argo data system, and following expert quality control as science-ready data in partnership with NOC research experts.”

The data will also be distributed through the UK Met Office to the World Meteorological Organisation’s Integrated Global Observing System (WIGOS) for the benefit of operational users.

The implementation of ASBAN-UK will coincide with the first part of the UN Decade of Ocean Science for Sustainable Development (2021–30) which presents an opportunity for a new link between science and innovation and the needs of society. ASBAN-UK will establish the strong base of a UK national facility that will provide data and information to inform policy in support of the UN Sustainable Development Goals.

Implementation will be underpinned by CLASS (Climate Linked Atlantic Sector Science), a NERC National Capability programme led by the NOC, that includes open ocean research ship expeditions to deploy the floats. Highly accurate data collected on CLASS expeditions will also be used to calibrate the float data, forming a component of the network essential to ensure data are of the highest quality.

Investment in the new BGC Argo floats is made through allocation of NOC capital resources and funding awarded from the NERC 2020 competitive Strategic Capital Call, supported by government’s World Class Labs funding scheme, via UKRI.