Detecting, attributing, and projecting global marine ecosystem and fisheries change: FishMIP 2.0

Abstract

There is an urgent need for models that can robustly detect past and project future ecosystem changes and risks to the services that they provide to people. The Fisheries and Marine Ecosystem Model Intercomparison Project (FishMIP) was established to develop model ensembles for projecting long-term impacts of climate change on fisheries and marine ecosystems while informing policy at spatio-temporal scales relevant to the Inter-Sectoral Impact Model Intercomparison Project (ISIMIP) framework. While contributing FishMIP models have improved over time, large uncertainties in projections remain, particularly in coastal and shelf seas where most of the world’s fisheries occur. Furthermore, previous FishMIP climate impact projections have mostly ignored fishing activity due to a lack of standardized historical and scenario-based human activity forcing and uneven capabilities to dynamically model fisheries across the FishMIP community. This, in addition to underrepresentation of coastal processes, has limited the ability to evaluate the FishMIP ensemble’s ability to adequately capture past states - a crucial step for building confidence in future projections. To address these issues, we have developed two parallel simulation experiments (FishMIP 2.0) on: 1) model evaluation and detection of past changes and 2) future scenarios and projections. Key advances include historical climate forcing, that captures oceanographic features not previously resolved, and standardized fishing forcing to systematically test fishing effects across models. FishMIP 2.0 is a key step towards a detection and attribution framework for marine ecosystem change at regional and global scales, and towards enhanced policy relevance through increased confidence in future ensemble projections.

Developing a Southern Ocean Marine Ecosystem Model Ensemble To Assess Climate Risks and Uncertainties

“…Building on previous efforts to enhance regional MEM for the Southern Ocean (Constable et al, 2023;McCormack et al, 2021;Murphy et al, 2012), and facilitated by the FishMIP 2.0 protocol (Blanchard et al, 2024;Ortega-Cisneros et al, this issue) and the extensive FishMIP network, we first assembled and consulted a group of experts in ocean, biogeochemical, biological and socio-ecological modelling. We determined that a skill assessment of the ocean-biogeochemical model environmental forcing variables (sea surface temperature (SST), sea ice concentration, and phytoplankton biomass: Table S1; collectively referred to as climate forcings from hereon in) used in FishMIP 3a and required to drive MEMs was necessary to establish if they are fit-forpurpose in Southern Ocean regions.…”

“…This is particularly relevant at the regional scale, where FishMIP outputs could play a critical role in informing climate-resilient fisheries policy and management. To build confidence in projections, a new phase of the model intercomparison project, FishMIP 2.0, considers aspects such as the use of higher spatial resolution, reanalysis-forced ocean model outputs, and globallystandardised fishing effort forcing the development of a model ensemble skill assessment and evaluation framework for FishMIP 3a (Blanchard et al, 2024;Frieler et al, 2024), as well as integration of future climate and fishing scenarios (Maury et al,this issue,FishMIP 3b).…”

“…FishMIP2.0 (Blanchard et al, 2024) also includes a detailed workflow to implement the regional MEM protocol (Ortega-Cisneros et al, this issue) to facilitate model intercomparison across scales and different parts of the world to help build regional modelling capacity, identify issues, and ultimately improve models. To address the research gap of robustly testing scenarios of past and future change (focus area 3; Murphy et al 2012), we propose the Southern Ocean Marine Ecosystem Model Ensemble (SOMEME; Figure 2) as a contribution to the FishMIP 2.0 regional model inter-comparison initiative.…”