Streaming Media

Presentation Abstract

Projections of the future ocean state for Canada’s Salish Sea are necessary to understand the effects of climate change on ecosystems, fisheries, and aquaculture providing critical information on likely future conditions and the ability to adaptively manage fisheries resources, ecosystems and significant areas. A multi-stage downscaling system is under development to improve our understanding of climate impacts for the Salish Sea and to generate actionable climate data for decision makers. Climate models are global and, therefore, are restricted to coarse resolutions on the order of 100km. The narrow straits and channels and complex bathymetry of the Salish Sea are modelled using a high-resolution ocean model known as the SalishSeaCast (500m). To drive the ocean model, the atmospheric climate forcing will be downscaled to a meaningful resolution. This project compares statistical and dynamical downscaling methods for downscaling the driving atmospheric fields to determine which method produces a more realistic ocean state. The downscaled fields will be used to analyze changes between a hindcast period (1986-2005) and future period (2046-2065) under two climate scenarios: the moderate mitigation representative concentration pathway (RCP) 4.5 and the no mitigation scenario RCP 8.5. The SalishSeaCast will be enhanced with a module for benthic respiration to improve the representation of biogeochemistry. The study will quantify changes in key stressors (e.g. temperature, oxygen, pH) and create maps of change to highlight ecologically significant areas for the purposes of conservation and protection. Additionally, we will investigate the impact of changing freshwater discharge on the Salish Sea marine ecosystem by conducting sensitivity tests using the recently available hydrological model projections of future discharge from the Fraser River under both future scenarios.

Session Title

Climate Science 2: Water

Conference Track

SSE8: Climate Change

Conference Name

Salish Sea Ecosystem Conference (2022 : Online)

Document Type

Event

SSEC Identifier

SSE-traditionals-78

Start Date

27-4-2022 9:45 AM

End Date

27-4-2022 11:15 AM

Type of Presentation

Oral

Genre/Form

conference proceedings; presentations (communicative events)

Contributing Repository

Digital content made available by University Archives, Heritage Resources, Western Libraries, Western Washington University.

Subjects – Topical (LCSH)

Climatic changes--Salish Sea (B.C. and Wash.); Ecosystem management--Salish Sea (B.C. and Wash.); Fisheries--Salish Sea (B.C. and Wash.)

Geographic Coverage

Salish Sea (B.C. and Wash.)

Rights

Copying of this document in whole or in part is allowable only for scholarly purposes. It is understood, however, that any copying or publication of this document for commercial purposes, or for financial gain, shall not be allowed without the author's written permission.

Type

Text

Language

English

Format

application/pdf

Share

COinS
 
Apr 27th, 9:45 AM Apr 27th, 11:15 AM

Projecting Future Climate States for the Salish Sea in Support of the Management of local Ecosystems and Fisheries

Projections of the future ocean state for Canada’s Salish Sea are necessary to understand the effects of climate change on ecosystems, fisheries, and aquaculture providing critical information on likely future conditions and the ability to adaptively manage fisheries resources, ecosystems and significant areas. A multi-stage downscaling system is under development to improve our understanding of climate impacts for the Salish Sea and to generate actionable climate data for decision makers. Climate models are global and, therefore, are restricted to coarse resolutions on the order of 100km. The narrow straits and channels and complex bathymetry of the Salish Sea are modelled using a high-resolution ocean model known as the SalishSeaCast (500m). To drive the ocean model, the atmospheric climate forcing will be downscaled to a meaningful resolution. This project compares statistical and dynamical downscaling methods for downscaling the driving atmospheric fields to determine which method produces a more realistic ocean state. The downscaled fields will be used to analyze changes between a hindcast period (1986-2005) and future period (2046-2065) under two climate scenarios: the moderate mitigation representative concentration pathway (RCP) 4.5 and the no mitigation scenario RCP 8.5. The SalishSeaCast will be enhanced with a module for benthic respiration to improve the representation of biogeochemistry. The study will quantify changes in key stressors (e.g. temperature, oxygen, pH) and create maps of change to highlight ecologically significant areas for the purposes of conservation and protection. Additionally, we will investigate the impact of changing freshwater discharge on the Salish Sea marine ecosystem by conducting sensitivity tests using the recently available hydrological model projections of future discharge from the Fraser River under both future scenarios.