Scientific Impacts

The expected scientific impacts stem from the complete availability of a Ready-for-climate analyses dataset. Indeed, by ensuring FAIR-compliancy and end-to-end workflow orchestration, this service empowers researchers with a single and efficient access to qualification tools, to the ancillary data sources they used as input, and enables their chained execution. This helps in efficiently delivering biogeochemical data, in a FAIR way, with the quality level required to perform climate change analyses, and thus helps addressing pressing global issues such as ocean acidification (pH), carbon and nutrient cycling (Chlorophyll-a and Nitrate), ecosystem resilience under climate stress, and supporting Copernicus Marine and Climate services in their ecosystem monitoring and forecasting services as well as EMODNET for the Marine Strategy Framework Directive.

This eased Q.C.V BGC service will benefit the scientific community through several downstream applications necessitating datasets with a quality and associated uncertainty compliant for climate analyses (climate-ready dataset), both for scientific and for operational users such as Copernicus or EMODNET. The delivery in a timely manner of climate-analysis-ready datasets allows the scientific community a quicker and enlarged uptake of these essential in-situ measurements into their studies, such as ocean acidification, nutrients and the carbon-cycle, or anthropogenic carbon uptake by the ocean. It also allows improvements for operational applications, including ocean and climate forecast and reanalyses. These ocean and climate reanalyses are in turn used by the scientific community to perform climate-change studies. They are also used specifically for satellite measurement calibration, and thus are beneficial to the scientific community using satellite dataset.

Besides serving the environmental community, it will also serve the purpose of the Life Science cluster Research Infrastructures such as EMBRC. Indeed, the study of marine life requires knowledge of the environment in which the population evolves and physical and biogeochemical properties of their biota are key to understand their movements, the evolution of their numbers, or study how they adapt to climate-change. The targeted dataset allows to uniquely provide a global, synoptic view and main movements of population. It also helps in responding to the European Marine Strategy Framework Directive, both from the large-scale impact into monitored regions, but also closer to the coast as Argo is also deployed in European marginal seas (e.g. Baltic Sea, Mediterranean Sea, Black Sea).

The service aims at improving the efficiency of the Qualification, Calibration and Validation processing of BGC data (also referred to as delayed mode processing). This service will increase the amount of available data timely-delivered with a high quality stamp, including improved uncertainty assessments. This Q.C.V. processing is primarily applied to data from the Argo array, which is used by a large international community and which allows a global and synoptic coverage, but it can also be applied to data from the Glider array. Both Argo and Glider are autonomous platforms providing BGC measurements that need to be Q.C.V.-ed while at sea (i.e. without having the instrument in hand as this is the case for BGC data acquired from Vessels). In that aspect, it’s a challenge for such complex and sensitive measurements.

The Q.C.V. process is essential to correct BGC variables from various physical and biogeochemical phenomena, such as sensor drift (quite common to a wide variety of sensors) or the quenching (specific to the case of Chlorophyll-a). It is the first time that such an end-to-end Q.C.V service is proposed to the community of Argo delayed mode operators. It will also be the first time that both glider and Argo data can be calibrated using the same service. The service can also facilitate cross-calibration experiments, and methods comparisons, helping in improving each other in a virtuous cycle, or else said cross-fertilisation with other marine Research Infrastructures. This cross-fertilisation is also eased with the use of the Galaxy Europe platform, which allows the simple design and re-use of workflows, and which is, by essence, a multi-domain framework.

Access to high-quality data is essential for ocean and climate scientific studies such as assessing the global characteristics and local variability of the deoxygenation, the ocean acidification, better understanding the carbon cycle and the anthropogenic carbon uptake by the ocean. It is noteworthy that most biogeochemical parameters are intertwined; let them be nitrate, Chlorophyll-a, oxygen, silicate, phosphate, pH, pCO2, light: all have their role into the carbon cycle.

The Argo array is unique; it allows measurements to be performed all over the world ocean, at any time of the year, when boats and very precise measurements are not possible. This allows understanding the characteristics and seasonal variability almost everywhere, even in regions and times where usual measures made from research vessels are not possible, e.g., the Polar regions. This autonomy of the Argo floats often comes with an impossibility to directly post-calibrate the sensor. This is the reason why continuous effort has been made in defining and developing calibration procedures, using external but close in time and space high-quality data (as compared to the region variability and correlation scales), which are less numerous but more accurate. Even for gliders, which drift at sea for a smaller time span, are systematically recovered and can be post-calibrated for sensor drift, there is a need to adjust for other phenomena such as the quenching correction. Calibration is most often performed per sensor, over its whole time series (drift assessment). Argo data have been highly quoted in scientific publications since the inception of the Argo array (early 2000s). Their numbers have reached between 80 and 100 articles each year with a European main author since 2014, and 3 to 4 times more publications at the international level (see https://www.euro-argo.eu/KPIs ). Argo data are also thoroughly quoted (44 mentions, 320 publications and 4 key figures) and its importance for climate monitoring highlighted in the 6th Intergovernmental Panel on Climate Change (IPCC) report as summarized in an infographic that can be viewed here.

In-situ data, such as Argo and glider data, are also integrated by operational users regarding ocean and ocean-atmosphere coupled models (European Copernicus Marine service reanalyses and other international services such as those from the USA/NOAA). Core parameters (temperature and salinity) are assimilated and significantly improve the accuracy of the models, this accuracy improvement being assessed through OSSE experiments, i.e. comparison of the model accuracy between various assimilation scenarios where all available data is assimilated, half of them, none of them. Operational users are eager to assimilate more widely BGC data to improve the reliability of environmental models. This step should be taken for the Digital Twin of the Ocean (EDITO). The in-situ accuracy and its accessibility plays a crucial role to improve the accuracy of Digital Twin of the Ocean reanalyses and predictive scenarios. In particular, the accessibility of high-quality BGC data improves the ability to derive as accurate as possible predictive scenarios. The developed service can be used by other observations that use the same methodology, or for which such methodology would be relevant. It can also be used to compute or to compare results for mutual improvements (GLIDER, but also for other oceanic in-situ arrays from Research Infrastructures such as JERICO or EMSO). This publication of processing methods in an easy-to-uptake service can also encourage other Research Infrastructures to offer the same kind of service, in a mutual emulation.