Periodic Reporting for period 2 - iAtlantic (Integrated Assessment of Atlantic Marine Ecosystems in Space and Time) Reporting period: 2020-12-01 to 2022-05-31 Summary of the context and overall objectives of the project iAtlantic aims to deliver an integrated assessment of ecosystem status and dynamics in the deep and open Atlantic Ocean, and targets fundamental gaps in our understanding of the resilience, drivers of ecosystem change and tipping points of Atlantic’s deep and open-ocean ecosystems. With 35 beneficiaries spanning 4 continents, iAtlantic takes a basin-scale, interdisciplinary scientific approach to unifying stakeholder efforts to better inform sustainable management and enhance human and observational capacity in an all-Atlantic context. The overall objectives are: 1.standardise South and North Atlantic Ocean observations to enable short, medium and long-term assessments of Atlantic Ocean circulation and physico-biogeochemical environment; 2.map deep and open-ocean ecosystems at basin, regional and local scales; 3.assess the stability, vulnerability, and tipping points of deep and open-ocean Atlantic ecosystems to changes in ocean circulation, and effects of single and multiple stressors; 4.align and enhance human, technological and data inter-operability capacities for cost-effective cooperation and planning across the Atlantic; and 5.define requirements for sustainable management with industry and governmental stakeholders to reflect societal needs and inform policy developments that ensure and encourage a sustainable Blue Economy. Work performed from the beginning of the project to the end of the period covered by the report and main results achieved so far During the 2nd period of iAtlantic, beneficiaries: •Created 2 statistical workflows and set 3 common research questions to standardise ecological time series analysis across our 12 Study Regions. •Analysed carbon and nutrients from water samples, investigated temperature and salinity in the Atlantic, and refined methodology for calibrating and processing data from moored sensors.•Deployed Pressure Inverted Echo Sounders for the South Atlantic Gateway array around 10°W between 19 and 35°S with results due at the end of 2022.•Used forcing data from the most-recent basin-scale INALT20-jra55 model simulations and data from tidal model solutions to provide outputs used to link observed distributions of benthic species and modelled environmental parameters.•Made progress towards basin-wide mapping with new bathymetry datasets by gathering new data and unlocking of existing data, particularly through collaboration with industry. •Completed the first basin-wide Atlantic marine landscape map. •Completed the first genomic analyses on the vent gastropod Peltospira smaragdina. •Shown that shifts in the upper ocean ecosystems caused by climate change and overfishing are likely to have significant impacts on the scavenger community at the deep seafloor. •Shown that the pelagic fauna is likely to increase metabolic rates to offset the effects of warmer temperatures in the water column, and is thus significantly impacted by climate change. •Investigated the severe toxic and lethal effects of mining on the larvae stages of the important reef-building coral Lophelia pertusa via physiological experiments combining ocean acidification and deep-sea mining.•Continued the compilation of the best available ocean-basin scale biogeographic and human-use data to produce transparent ocean basin scale management scenarios for the whole Atlantic.•Maintained and expanded the iAtlantic GeoNode, the web-GIS platform for the visualisation of data in the iAtlantic study regions and regions of interest. •Intensified the efforts to source and supplement the existing GeoNode layers with more industry/human use data layers.•Continued working with the consortium to identify potential diverse sources of data.•Updated the map of the iAtlantic regional boundaries. •Finalised the goals and objectives for the development of iAtlantic’s Systematic Conservation Planning scenarios.•Launched the All-Atlantic Data Community Portal on the GEOSS Portal, granting access to as many of the used Atlantic data resources as possible through a single portal access point.•Established a successful workflow to provide access to the iAtlantic data layers archived and published by the PANGAEA World Data Centre via the iAtlantic GeoNode.•Progressed with connecting the PANGAEA data resources through the different EMODnet thematic portals (e.g. EMODnet Biology).•Published over 60 datasets, 40 of which have been curated and archived by PANGAEA, including hard-to-access industrial datasets from Petrobras.•Compiled the 1st project-wide inventory of all iAtlantic-related datasets.•Addressed the COVID-19-related restrictions on in-person events by going online and/or by the clever use of online platforms and social media.•(Co-)hosted 3 satellite activities in connection with 3 different UN Decade of Ocean Science for Sustainable Development laboratory themes.•Continued the monthly iAtlantic ‘Follow the Fellows’ and thematic webinars.•Appointed the iAtlantic Innovation and Exploitation Manager to support and maximise the take-up and impact of project results.•Maintained strong links and continued following external groups from industry, sectoral bodies, regional authorities, international and intergovernmental organisations, civil society groups and other science networks.•Carefully designed our stakeholder strategy once international in-person meetings restart, being sensitive to stakeholders’ priority changes and pressures on agendas.•Maintained the iAtlantic Fellowship, the cohort of early-career researchers within iAtlantic.•Maintained the iAtlantic Expeditions Replanning Working Group to mitigate the risks posed by the COVID-19 pandemic to the iAtlantic cruises.•Responded to consultation exercises launched by stakeholder organisations.•Published 40 papers in peer-reviewed scientific journals. Progress beyond the state of the art and expected potential impact (including the socio-economic impact and the wider societal implications of the project so far) iAtlantic endeavours to facilitate the implementation of the Belém Statement on Atlantic Ocean Research and Innovation Cooperation (2017) through supporting collaboration between project partners from Europe, Africa and North and South America. It is expected that iAtlantic will greatly enhance the monitoring, modelling, planning, management, and prediction capacities across the Atlantic (e.g. through the mapping of Atlantic ecosystems at various spatial scales). As an interdisciplinary research project, iAtlantic’s results are highly relevant addressing current issues that beset deep and open-ocean ecosystems, and subsequently societies who rely on the services rendered from these ecosystems, in what is now a rapidly changing ocean. iAtlantic aims to assess ecosystem status under current and future climate scenarios and better understand the impacts of multiple stressors on ecosystem functioning. The project also aims to increase the competitiveness of EU’s Blue Economy by developing new technologies to service societal needs and new value chains (e.g. through the demonstration of novel machine learning solutions for advanced monitoring of Atlantic resources). iAtlantic's fundamental ambition is to provide the evidence required to inform sustainable management of Atlantic ecosystems to avoid significant adverse impacts and facilitate the achievement of healthy and productive waters (e.g. through the development of area-based management tools to facilitate marine spatial planning). As such, iAtlantic will contribute towards Sustainable Development Goal 14, as well as to overarching policy processes (e.g. engagement in ongoing negotiations for the conservation and sustainable use of marine biodiversity in areas beyond national jurisdiction. Humpback whale breaching off the eastern coast of USA. Image courtesy T.Kelley.