biogeochemical Argo

biogeochemical Argo
Name	Biogeochemical Argo
Caption	Autonomous profiling float
Founded	2007
Founders	Global Ocean Observing System; Argo
Area served	Global oceans
Product	Ocean biogeochemical profiles

biogeochemical Argo

Biogeochemical Argo is an international program deploying autonomous profiling floats to collect oceanographic biogeochemical observations for climate, ecosystem, and biogeochemical cycle research. The initiative extends the Argo program by equipping floats with sensors to measure parameters relevant to the carbon cycle, marine ecosystems, and ocean biogeochemistry. It links operational networks, research institutes, and funding agencies to provide near-real-time, global-scale datasets supporting Intergovernmental Panel on Climate Change, International Ocean Discovery Program, and regional monitoring efforts.

Overview and Objectives

The program's primary objectives include documenting marine carbon dynamics, tracking oxygen and nutrient distributions, and resolving seasonal-to-decadal variability to inform IPCC assessments, Global Ocean Observing System, and national monitoring such as National Oceanic and Atmospheric Administration initiatives. Biogeochemical Argo aims to integrate with projects led by National Aeronautics and Space Administration, European Space Agency, Scripps Institution of Oceanography, and Woods Hole Oceanographic Institution to provide interoperable data for modeling centers like NOAA National Centers for Environmental Prediction, European Centre for Medium-Range Weather Forecasts, and Plymouth Marine Laboratory. Goals also include supporting ecosystem-based management under frameworks endorsed by United Nations bodies and informing programs such as the Global Carbon Project and regional efforts like Integrated Marine Observing System.

Instrumentation and Float Technology

Floats are based on core designs from Argo manufacturers including Teledyne Webb Research and Sea-Bird Electronics. Profiles are obtained using buoyancy-driven vehicles derived from Provor and NINJA variants; platform control and telemetry rely on satellite systems like Argos (satellite system) and Iridium (satellite communications). Engineering partnerships involve Monterey Bay Aquarium Research Institute, Royal Netherlands Institute for Sea Research, and French Research Institute for Exploitation of the Sea. Power management, corrosion control, and sensor integration are developed in collaboration with laboratories such as Lamont–Doherty Earth Observatory and University of Washington.

Measured Parameters and Sensors

Biogeochemical Argo floats commonly carry sensors for dissolved oxygen, nitrate, pH, chlorophyll fluorescence, and backscatter. Specific instruments include optodes from Aanderaa for oxygen, ISUS nitrate sensors from Satlantic, pH sensors developed at MBARI or GEOMAR, and ECO triplet fluorometers by WetLabs. Emerging payloads measure dissolved inorganic carbon and alkalinity using technologies advanced at Scripps Institution of Oceanography and Laboratoire des Sciences du Climat et de l'Environnement. Sensor calibration and development draw on expertise from Brookhaven National Laboratory, National Oceanography Centre, and Plymouth Marine Laboratory.

Deployment, Coverage, and Data Collection

Deployment strategies are coordinated among national programs including NOAA, CSIRO, Institut Français de Recherche pour l'Exploitation de la Mer, and regional consortia such as SOCCOM. Floats are deployed from research vessels like R/V Roger Revelle, RRS Sir David Attenborough, and RV Investigator and sometimes air-dropped from aircraft used by United States Air Force Reserve Command for polar access. Coverage emphasizes biomes monitored by Southern Ocean Observing System, California Current Ecosystem, and North Atlantic Bloom Experiment regions, with particular campaigns coordinated with International CLIVAR Project and Global Ocean Ship-based Hydrographic Investigations Program.

Data Processing, Quality Control, and Accessibility

Data pipelines follow standards developed by Argo and are integrated into repositories managed by Argo Information Centre, UK Met Office, and Copernicus Marine Service. Real-time telemetry uses Iridium (satellite communications) and Argos (satellite system) with delayed-mode quality control performed by expert panels from Argo Data Management Team, IOCCP, and the Global Ocean Oxygen Network. Quality control protocols reference procedures from World Meteorological Organization and are compatible with assimilation systems at the National Centers for Environmental Prediction. Data are distributed under open access policies, enabling reuse by Plymouth Marine Laboratory, Lamont–Doherty Earth Observatory, and initiatives like the Global Carbon Project.

Scientific Contributions and Applications

Biogeochemical Argo has advanced understanding of ocean deoxygenation reported in studies linked to IPCC assessments and has provided constraints on regional carbon uptake quantified by Global Carbon Project analyses. The floats have revealed patterns in phytoplankton phenology relevant to Longhurst biogeographical provinces and supported ecosystem forecasts used by NOAA Fisheries and ICES. Observations have been assimilated into models developed at Geophysical Fluid Dynamics Laboratory, NOAA Geophysical Fluid Dynamics Laboratory, and European Centre for Medium-Range Weather Forecasts to improve projections of the Atlantic Meridional Overturning Circulation and coastal hypoxia documented by regional programs like Chesapeake Bay Program.

Challenges, Limitations, and Future Directions

Challenges include sensor biofouling, calibration drift addressed by intercalibration campaigns led by IOCCP and GLODAP efforts, and sparse coverage in polar and marginal seas tackled by programs such as SOCCOM and Arctic Observing Network. Funding and coordination among agencies like NOAA, European Commission, and national ministries remain critical for scaling to the target global array. Future directions emphasize integrating biogeochemical floats with autonomous vehicles from MBARI, satellite missions by NASA and ESA, and high-resolution models at NCAR to close observational gaps and support policy-relevant synthesis for bodies like the United Nations Framework Convention on Climate Change.

Category:Oceanography Category:Climate science Category:Biogeochemistry