Stephanie Peacock 2024-02-13
Climate Change Vulnerability Assessments (CCVAs) aim to quantify the potential impact of climate change on certain valued attributes of a particular system to inform the identification and prioritization of conservation and mitigation actions. In this project, we are interested in the potential impact of climate change on the viability of Pacific salmon and steelhead Conservation Units (CUs), with the aim to understand which CUs are likely to be most strongly affected and why. For more information on the project, see the Salmon Watersheds Program website.
Our approach to CCVAs involves quantifying exposure to climate
changes as predicted by Global Climate Models, considering the unique
spatial distribution and life-history timing of each CU. We are
considering climate changes throughout the salmon life cycle, and the
code and data here are organized into freshwater and marine
sub-directories because the data sources and processing for these two
environments are different.
Within the freshwater and marine folders, there are R files in
code that read in climate output, organize and summarize it, and
calculate exposure for each CU, life stage, and climate attribute. As of
Febraury 2024, these calculations have been applied for 60 CUs in the
Fraser River basin.
Note that raw data files consist of Global Climate Model projections and are large files (hundreds of GB). These are therefore not made available on GitHub but can be downloaded from the relevant sources listed in the table below or by contacting the project lead (Stephanie Peacock, speacock at psf dot ca).
| Environment | Exposure attribute | Definition | Dataset |
|---|---|---|---|
| Freshwater | Stream temperature | The number of days within each life stage that stream temperature is above a species- and stage-specific upper threshold | Pacific Climate Impacts Consortium gridded hydrologic model output |
| Freshwater | Low flow | The number of days within each freshwater life stage that flow is below 20% of the Mean Annual Discharge (MAD) for the grid cell | Pacific Climate Impacts Consortium gridded hydrologic model output |
| Marine | Sea surface temperature | The number of months that SST is above the “core thermal range” during the marine stages. Core thermal range was defined by Langan et al (in review) based on ocean habitat use by each species. | NOAA’s Climate Change Web Portal |
| Marine | Sea surface salinity | The number of months that salinity was below the 2.5 percentile of historical salinity within each grid cell (i.e., had a z-score of less than -2). | NOAA’s Climate Change Web Portal |
This work is funded by the BC Salmon Restoration and Innovation Fund. We are extremely grateful to PSF’s Climate Science Advisory Committee, who have provided input on our approach. We thank Markus Schnorbus at PCIC for providing preliminary hydrologic model outputs so we can advance this work.