Integrated Modeling to Evaluate Climate Change Impacts on Coupled Social-Ecological Systems in Alaska

Abstract

Hollowed et al. Alaska Integrated Climate Modeling including projections of catch for core species under baseline (status quo) fishing conditions and two alternative fishing scenarios are discussed. The ACLIM modeling framework serves as a guide for multidisciplinary integrated climate impact and adaptation decision making in other large marine ecosystems.

Ensemble Projections of Future Climate Change Impacts on the Eastern Bering Sea Food Web Using a Multispecies Size Spectrum Model

“…Modeling frameworks that link global climate processes to regional ecological systems are vital test beds for evaluating management strategies under climate change (e.g. Weijerman et al, 2016;Hollowed et al, 2019). The framework presented here makes significant inroads in this regard and offers a template for other systems.…”

“…This information can help inform and prioritize development of more concerted research programs based on both the species and objective. While we have partly focused on one facet of structural uncertainty at the MSSM level, we note that other single and multispecies models may also offer plausible representations of EBS fish and crab species dynamics and a major goal of ACLIM is to bracket the possible range of ecological effects of climate change by including models that differ in terms of their strengths and weaknesses (Hollowed et al, 2019). We expect ensemble projections that include a broader set of structurally distinct higher trophic level models will increase projection uncertainty.…”

“…We evaluated three fishery management scenarios based on current policies for setting total allowable catch (TAC). This procedure is essential because the Bering Sea-Aleutian Islands ecosystem cap requires that individual species TACs be reduced so that the sum of all species is at or below the 2 million metric ton ecosystem cap (Hollowed et al, 2019). We considered scenarios in which: (1) TAC was allocated based on recent historical patterns ("status quo"); (2) pollock and Pacific cod TAC is increased up to 10% relative to status quo at the cost of lower flatfish TAC, and (3) flatfish TAC was increased up to 10% relative to status quo at the cost of lower pollock and Pacific cod TAC.…”

“…However, out of practical necessity these studies lack taxonomic detail, make simplifying assumptions regarding growth potential and trophic structure, and are forced with ESM projections with coarse spatial resolution. To better understand the implications of climate change for higher trophic level species and their fisheries in the EBS, the interdisciplinary Alaska Climate Integrated Modeling project (ACLIM) was initiated by the NOAA Alaska Fisheries Science Center (Hollowed et al, 2019). As a component of ACLIM, capacity to dynamically downscale ESM projections to the EBS was expanded (Hermann et al, 2019) and an MSSM was developed for and calibrated to the EBS (Reum et al, 2019).…”

“…The first relates to different scenarios of future GHG emissions (Payne et al, 2015;Cheung et al, 2016). The second corresponds to different fisheries management scenarios that, relative to status quo, prioritize fishing on different components of the EBS food web and reflect trade-offs fishery managers are confronted with in setting total allowable catches for each stock (Figure 1; Hollowed et al, 2019).…”