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Subtidal seabed sediments are one of the planet's biggest organic carbon stores, but have been poorly considered in nature‐based climate change mitigation. Protection of the seabed is predominantly through establishment of marine protected area (MPA) networks, but their emphasis on biodiversity may limit their carbon value. The United Kingdom has one of the most extensive networks of MPAs in the world, yet damaging human activities are excluded from only a small portion. We calculate that full protection of the MPA network would offer limited carbon benefit, due to below average organic carbon stocks and disturbance from mobile fishing gears when compared to the entire U.K. seabed. We find that inshore exclusion zones (where mobile gears are restricted from nearshore areas to benefit biodiversity and low‐impact fishers) could offer greater carbon benefits compared to MPAs. However, neither of these biodiversity‐focused protection strategies are as effective for seabed carbon as targeted protection. [ABSTRACT FROM AUTHOR]

The Paris Agreement on climate change has calls for urgent, radical, and transformative actions in mitigation and adaptation, particularly in terms of reducing greenhouse gas (GHG) emission. There are many terms used to describe the process of reducing GHGs, including decarbonization, low carbon development (LCD) or low carbon transition (LCT). The conceptualization of these terms remains puzzling and there has not been any consensus to explain the meaning and their interrelationship. Clearer definition and conceptual boundaries are necessary to improve the coherence of overarching practices to cut CO 2 emission. The paper aims to review key concepts related to climate change mitigation related to the reduction of CO 2 and efforts toward net-zero emission in the academic literature, by (1) examining progress of the literature over time, (2) identifying geographical locus and sectoral focus of the literature, (3) determining the interrelationships between the key concepts. We use a Systematic Literature Review (SLR) method for data collection by selecting peer-reviewed literature from Scopus and analyzing the data with content analysis and bibliometric analysis. The findings are, firstly, the publications of the literature are influenced by global and national climate change policies and the interest of scholars affiliated to institutions from major emitter countries. Therefore, the literature is mostly originating from countries that emit the most CO 2 while also implement mitigations to reduce CO 2 emission. Secondly, China is the country where studies are mostly focused and also where the authors are affiliated/located. However, publications from the United Kingdom are cited the most. Thirdly, there are three clusters of literature found, namely that LCD and LCT are the terms used to identify visions for climate mitigation, while decarbonization is the actions and processes to achieve either LCD or LCT (as the visions). • The dynamic of climate change policies influence the literature trend. • The literature is mostly originating from major CO 2 emitter. • Low carbon development and low carbon transition are visional terms. • Decarbonization indicates the processes of decoupling CO 2 to achieve the visions. [ABSTRACT FROM AUTHOR]

The global carbon cycle is currently being perturbed by the large-scale burning of fossil fuels, leading to rising global temperatures and related stress and damage to life on Earth. At the same time, we lack a detailed understanding of the various reservoirs and fluxes of the coastal and marine carbon cycle. Quantification of marine organic carbon stocks and their vulnerability to climate change and human activities is crucial for effective climate change mitigation and other management strategies. Recently, research has focussed on the ability of salt marshes, mangroves, seagrasses and macroalgae, so-called Blue Carbon ecosystems, to remove carbon dioxide from the atmosphere and store it as organic carbon. Likewise, fjords have been identified as locations of rapid burial of organic carbon. Less attention has, however, been directed to continental shelf sediments, presumably due to low carbon densities found in such sediments. Despite this, there are indications that organic carbon stocks of surficial shelf sediments are important: It was estimated that the upper 10 cm of the north-west European continental shelf sea sediments store between 230 and 882 teragrams (Tg) of organic carbon. A recent study found that organic carbon stocks of continental shelf sediments by far exceed those of salt marshes and seagrasses in the United Kingdom. Additionally, it was reported that marine sediment organic carbon stocks might be of similar magnitude as terrestrial soil stocks in some maritime nations.Here we report on initial results of a pilot study, which aims to spatially predict organic carbon stocks and burial rates of surface sediments in the Norwegian Trough and North Sea. This pilot study attempts to establish suitable methodologies for making such spatial predictions based on a comprehensive set of existing data on organic carbon concentrations, sediment properties and sedimentation rates. It is hoped that a complete assessment of stocks and burial rates on the Norwegian continental shelf will subsequently be conducted under the auspices of the MAREANO seafloor mapping programme. Initial results indicate that the Norwegian Trough stores approximately 67 Tg of organic carbon in the upper 10 cm of the sediment column alone. By comparison, the sediments of the Norwegian part of the North Sea, which have organic carbon densities typical for the north-west European continental shelf, contain approximately 36 Tg of organic carbon in an area that is 25% larger than the Norwegian Trough. These results indicate that the Norwegian Trough is an important regional store for organic carbon. Subsequent analysis will attempt to shed light on burial rates and the residence time of organic carbon within the zone of active degradation. [ABSTRACT FROM AUTHOR]