Climate change scenarios in fisheries and aquatic conservation research

Abstract

Climate change projections are central to fisheries and aquatic conservation research, and to planning for a warming world. Such projections include assumptions about future emissions pathways and climate-system sensitivity to emissions. Fisheries and aquatic conservation research typically uses emissions scenarios created for the Intergovernmental Panel on Climate Change (IPCC). However, recent climate research and global development trends have significantly changed our understanding of the ranges of plausible emissions pathways to 2100 and climate sensitivities. Here, we provide a concise review of these updates to our understanding of climate futures, and we make recommendations for best-practice use of climate change scenarios in fisheries and aquatic conservation research. Although emissions pathways are subject to deep uncertainty, recent research suggests that emissions scenarios producing a range of approximately 3.4-4.5W/m2 radiative forcing by 2100 might be most plausible. With median climate sensitivities, this corresponds to approximately 2-3 degrees C global warming by 2100. Climate-sensitivity uncertainties expand this range to approximately 1.5-4 degrees C. In terms of the Shared Socioeconomic Pathways (SSPs) and Representative Concentration Pathways (RCPs), radiative forcing outcomes mostly fall between SSP2-3.4 and SSP2-4.5/RCP4.5, though higher and lower emissions scenarios (e.g., RCP2.6 and RCP6.0) might be plausible and should be explored in research. However, we argue that uses of the highest-emission scenarios (RCP8.5/SSP5-8.5, SSP3-7.0)—which currently predominate the literature—should come with clearly articulated rationales and appropriate caveats to ensure results are not misinterpreted by scholars, policymakers, and media.

Distribution and predicted climatic refugia for a reef‐building cold‐water coral on the southeast US margin

“…Our notable findings of potential climate refugia on the eastern Blake Plateau warrant additional protections including the extension of the HAPC to unprotected mound features (Figure 1), to prevent damaging these valuable ecosystems with bottom‐contact fishing gear. Our study also highlights the utility of regional models in refining habitat suitability projections from coarser models (e.g., Davies et al, 2008; Morato et al, 2020), and of using multiple climate scenarios rather than a single business‐as‐usual scenario that is unlikely to occur (Burgess et al, 2022; Meinshausen et al, 2022). Indeed, visual comparison of our model outputs with those from Morato et al (2020) suggest that more of the eastern Blake Plateau is within the current climatic niche of L. pertusa (Figure S3.11), which may also be due in part to our inclusion of additional occurrence locations.…”

“…Our notable findings of potential climate refugia on the eastern Blake Plateau warrant additional protections including the extension of the HAPC to unprotected mound features (Figure 1), to prevent damaging these valuable ecosystems with bottom-contact fishing gear. Our study also highlights the utility of regional models in refining habitat suitability projections from coarser models (e.g., Davies et al, 2008;Morato et al, 2020), and of using multiple climate scenarios rather than a single business-as-usual scenario that is unlikely to occur (Burgess et al, 2022;Meinshausen et al, 2022).…”

Species redistribution creates unequal outcomes for multispecies fisheries under projected climate change

“…The variation in our projections represents a range of plausible futures, and we would therefore recommend the multimodel or ensemble approach to other SDM practitioners. Future studies using SDMs should continue to assess multiple model types or formulations and consider alternative climate models or at least present their results with appropriate caveats (62,63). Furthermore, climate change will affect other key aspects of fish stock productivity that are beyond the scope of this study, including alterations to age and size structure, ontogeny, recruitment, and food web structure [e.g., (64)(65)(66)].…”

Rebuilding Mediterranean marine resources under climate change

“…Hausfather & Peters 2020, Schwalm et al 2020, Arias et al 2021). RCP8.5 is one of the most commonly used scenarios in the climate impact literature, but it is increasingly considered as unrealistic in its assumptions (Kemp et al 2022, Burgess et al 2023. Future works using OSMOSE-MED to explore consequences of future management decisions under climate change should therefore consider more plausible median scenarios such as SSP2-3.4 and SSP2-4.5 (Pielke et al 2022, Burgess et al 2023.…”

“…RCP8.5 is one of the most commonly used scenarios in the climate impact literature, but it is increasingly considered as unrealistic in its assumptions (Kemp et al 2022, Burgess et al 2023. Future works using OSMOSE-MED to explore consequences of future management decisions under climate change should therefore consider more plausible median scenarios such as SSP2-3.4 and SSP2-4.5 (Pielke et al 2022, Burgess et al 2023. Second, we employed a range of fairly simplistic fishing scenarios that do not incorporate spatial, seasonal or ontogenic variations in the fishing mortality applied to each species.…”