Science-Based Development of the Rolling Review of Requirements for a Comprehensive Ocean Observing System

The increasing impacts of climate change on ocean systems underscore the need for a comprehensive, sustained, and rationalized ocean observing system. Such a system is essential for acquiring high-quality, accessible data that supports our understanding of ocean-climate interactions, enables assessment of environmental impacts of climate change, and informs climate adaptation and risk mitigation strategies. This proposal emphasizes the collaborative efforts of national and international entities, particularly through initiatives involving the Global Ocean Observing System (GOOS), the Global Climate Observing System (GCOS), and the World Meteorological Organization (WMO). These organizations, supported by initiatives such as the UN Ocean Decade’s Ocean Observing Co-Design and international projects like the EU Horizon Europe ObsSea4Clim and the GOOS Indicators  framework, are advancing the scientific design of a cohesive ocean observing system.

A structured, science-based framework for ocean observations is essential for understanding and addressing climate-driven changes and extremes in marine environments. Central to this effort is the WMO’s Rolling Review of Requirements (RRR) framework, initially developed for Numerical Weather Prediction. The ObsSea4Clim project contributes to this goal by advancing the RRR for ocean applications areas through a systematic approach centered on GOOS Essential Ocean Variables (EOVs) and GCOS Essential Climate Variables (ECVs). By building standardized indicators based on these variables, ObsSea4Clim is setting the foundation for a rationalized, robust ocean observing system that supports a wide range of future ocean applications. It also stimulates the regional/global ocean observing development through the best practice sharing and helps reverse the decline of the data stream (e.g. over the Indo-Pacific Warm Pool) in response to the covid-19 impact.  In parallel, the UN Decade on Ocean Sciences program Ocean Observing Co-Design, prioritizes co-designed, multipurpose observations that address both scientific and societal needs.

Through targeted test cases, both ObsSea4Clim and Ocean Observing Co-Design address key ocean changes—such as warming, ocean stratification. and sea-ice loss—and extreme events like marine heat waves and tropical cyclones. These application areas not only demonstrate the importance of sustained, reliable ocean data but also establish methods for evaluating the adequacy of observations and highlighting priority areas for monitoring. This framework thus provides a pathway to standardize observational requirements and enhance data consistency, paving the way for global adoption.

A core objective of ObsSea4Clim within the RRR process is to establish guidance and best practices for future ocean observing applications. The project’s adherence to the FAIR (Findable, Accessible, Interoperable, Reusable) and CARE (Collective benefit, Authority, Responsibility, Ethics) data principles ensures that the collected data supports integrated climate assessments, enhances predictive models, and facilitates evidence-based decision-making. By focusing on the interactions among climate drivers and developing multivariate indicators, ObsSea4Clim aims to create a versatile framework that can adapt to evolving scientific and societal needs, thereby supporting sustainable ocean and climate management.