Spatial priorities for climate-change refugia in British Columbia (Version 2.1)

Overview

This dataset provides spatial priorities for climate-informed conservation and restoration planning across British Columbia. The products integrate multiple indicators of macrorefugia and microrefugia using the Core Area Zonation (CAZ) algorithm in Zonation.

Macrorefugia represent relatively large areas with the potential to maintain suitable climatic conditions or species habitat as climate changes. Microrefugia represent locations where fine-scale topographic, hydrologic, ecological, or disturbance-related conditions may locally buffer ecosystems from regional climate change.

The resulting spatial prioritizations are intended to support climate-informed land stewardship and protected-area planning. They can be used to identify areas with high potential to support biodiversity persistence under climate change, evaluate existing conservation networks, and distinguish areas where conservation versus restoration may be appropriate.

Analyses were conducted at 1-km spatial resolution in the NAD 1983 BC Albers projection. Ranked Zonation priorities range from 0 (lowest priority) to 1 (highest priority).

Land relationship acknowledgement

We respectfully acknowledge that we live and work across diverse unceded territories and treaty lands and pay our respects to the First Nations, Inuit and Métis ancestors of these places. We honour our connections to these lands and waters and reaffirm our relationships with one another.

Methods

1. Macrorefugia

Macrorefugia priorities incorporated both climate-based and species-specific indicators.

Climate-type macrorefugia were represented by forward and backward climate velocity for an ensemble of eight CMIP6 global climate models under SSP2-4.5. Climate-velocity values were transformed so that higher values represented greater refugia potential.

Species-specific macrorefugia represented areas with relatively high potential to retain suitable climatic habitat through time. Separate Zonation scenarios were developed for:

• rare species in British Columbia (833 Red-listed, Blue-listed, and SARA Schedule 1 species), grouped by major taxonomic group;

• 142 climate-sensitive bird species; and

• 10 dominant tree species in British Columbia.

Species-specific macrorefugia inputs were based on indices ranging from 0 to 1, with higher values indicating greater macrorefugia potential.

Taxon-specific Zonation outputs were subsequently combined with forward and backward climate-type velocity in an overall macrorefugia CAZ scenario. Inputs were equally weighted. Separate analyses were conducted for the 2050s (2041–2070) and 2080s (2071–2100) under SSP2-4.5.

2. Microrefugia

A separate CAZ scenario combined six indicators of microrefugia:

1. topodiversity;

2. cool slopes, glaciers, and wetlands;

3. topographically mediated fire refugia;

4. thermal refugia;

5. drought refugia; and

6. old-growth forest.

Inputs were transformed to a common interpretation in which higher values indicated greater microrefugia potential. Binary indicators were assigned values of 0 or 1, while continuous or categorical products were rescaled or reclassified as described in Table 1. 

The six microrefugia indicators were equally weighted in the CAZ analysis. Microrefugia were treated as temporally static and therefore used for both future periods.

3. Combined macrorefugia and microrefugia priorities

The macrorefugia and microrefugia Zonation outputs were combined in a final CAZ scenario, with equal weighting of the two components.

Separate combined prioritizations were produced for the 2050s and 2080s.

4. Conservation and restoration priorities

A post hoc human-footprint mask derived from the British Columbia cumulative-effects dataset was applied to the combined Zonation outputs.

Areas of low human footprint were classified as candidates for area-based conservation, whereas areas of high human footprint were classified as candidates for restoration or other management actions. 

These products should therefore be interpreted as relative spatial priorities under the assumptions and inputs of the prioritization framework, rather than as prescriptive designations of areas that should necessarily be protected or restored.

Table 1. Spatial inputs used to identify macrorefugia and microrefugia

Note: Macrorefugia inputs were first combined within relevant taxonomic groups and then integrated with climate-type velocity in the overall macrorefugia scenario. The six microrefugia indicators were combined in a separate, equally weighted CAZ scenario. Macrorefugia and microrefugia outputs were subsequently combined with equal weighting to produce the final 2050s and 2080s prioritizations.

Files and directory structure

Zonation_macro.7z

Contains outputs from the macrorefugia Zonation CAZ analyses.

Taxon-specific outputs are provided for the individual taxonomic groups used in the macrorefugia analysis, with separate results for the 2050s and 2080s.

Examples:

amph_rept_CAZ_2050s.tif
amph_rept_CAZ_2080s.tif

The archive also contains the combined macrorefugia scenarios:

macro_all_CAZ_2050s.tif
macro_all_CAZ_2080s.tif

These combine the taxon-specific macrorefugia priorities with forward and backward climate-type velocity.

Associated .lyrx files provide ArcGIS layer symbology, and .tfw files provide raster georeferencing information.

In addition, a list of bird species is included in the bird macrorefugia component of the Zonation analysis:

Birds_species_included_in_Zonation_macrorefugia_scenarios.txt

Zonation_micro.7z

Contains the combined microrefugia Zonation CAZ output:

micro_CAZ.tif

This scenario integrates topodiversity; cool slopes, glaciers, and wetlands; fire refugia; thermal refugia; drought refugia; and old-growth forest.

Zonation_macro_micro.7z

Contains the final combined macrorefugia and microrefugia prioritizations and the products derived after application of the human-footprint mask.

macro_micro_CAZ_2050s.tif
macro_micro_CAZ_2080s.tif

These represent combined, unmasked macrorefugia and microrefugia priorities.

Conservation priorities

conservation_priorities_2050s.tif
conservation_priorities_2080s.tif

These represent combined macrorefugia and microrefugia priorities occurring in areas classified as having low human footprint.

Restoration priorities

restoration_priorities_2050s.tif
restoration_priorities_2080s.tif

These represent combined macrorefugia and microrefugia priorities occurring in areas classified as having high human footprint.

Associated .lyrx files provide ArcGIS layer symbology.

Zonation_priorities_by_ecoprovince.7z

Contains the following root folders:

/Macro_scenarios/

/Micro_scenarios/

/Macro_Micro_scenarios/

Within each root folder are .jpg and .tif (GeoTIFF) files of Zonation priorities for the 2050s and 2080s (except for the microrefugia scenarios) using the same inputs as described for the province-wide scenarios above.

Example:

%taxon_name%_CAZ_2050s_BOP.CAZ_E.jpg

%taxon_name%_CAZ_2050s_BOP.CAZ_E.rank.compressed.tif

CAZ = Core Area Zonation

BOP = Boreal Plains ecoprovince (in this example)

rank.compressed.tif = the Zonation ranking for the ecoprovince and scenario

"macro_all" refers to the combination of taxonomic groups plus macrorefugia potential based on forward and backward velocity

Zonation analyses by ecoprovince were performed using the 'analysis area mask' setting in Zonation.  This allows the algorithm to prioritize pixels relative to the rest of the ecoprovince rather than the entire province of British Columbia. Both approaches are useful depending on land stewardship objectives.  Please see Table 1 for the list of spatial inputs.

Terrestrial ecoprovinces of British Columbia:

BOP    BOREAL PLAINS
CEI    CENTRAL INTERIOR
COM    COAST AND MOUNTAINS
GED    GEORGIA DEPRESSION
NBM    NORTHERN BOREAL MOUNTAINS
SAL    SOUTHERN ALASKA MOUNTAINS
SBI    SUB-BOREAL INTERIOR
SIM    SOUTHERN INTERIOR MOUNTAINS
SOI    SOUTHERN INTERIOR
TAP    TAIGA PLAINS

Footprint.7z

Contains:

footprint.tif

Binary human-footprint layer derived from the Government of British Columbia (2022) cumulative-effects dataset and resampled to the 1-km analysis grid.

Values:

0 = low/no mapped human footprint
1 = mapped human footprint

This layer was used only as a post hoc mask to divide the final Zonation prioritization into conservation and restoration products; it was not itself a Zonation prioritization feature.

Interpretation of Zonation outputs

Zonation raster values range continuously from 0 to 1:

0 = lowest relative priority
1 = highest relative priority

Values represent relative rankings within the geographic extent of a given analysis. Consequently, rankings from the province-wide analysis and ecoprovince-specific analyses should not be interpreted as directly equivalent.

The products identify relative spatial priorities given the particular refugia indicators, transformations, weighting decisions, climate scenarios, and Zonation settings used in this analysis. They are intended as decision-support products rather than definitive classifications of climate-change refugia.

Raster specifications

Format: GeoTIFF
Pixel type: Floating point
Compression: LZW
Cell size: 1,000 × 1,000 m
Columns: 1,598
Rows: 1,369
Bands: 1

Coordinate reference system

Projected coordinate system: NAD 1983 BC Albers
Datum: NAD83
Linear units: metres
Central meridian: −126
Latitude of origin: 45
Standard parallel 1: 50
Standard parallel 2: 58.5
False easting: 1,000,000 m
False northing: 0 m

Geographic extent

West: −139.061502°
East: −110.430823°
South: 47.680823°
North: 60.605550°

Suggested citation

Stolar, J., Stralberg, D., Raymundo Sanchez, A. A. P., Kehm, G., Naujokaitis-Lewis, I., & Nielsen, S. E. (2026). Spatial priorities for climate-change refugia in British Columbia (Version 2.1) [Data set]. University of Alberta. Zenodo. https://doi.org/10.5281/zenodo.21027179

Corresponding author: stolar@ualberta.ca

References

Bateman, B. L., Wilsey, C., Taylor, L., Wu, J., LeBaron, G. S., & Langham, G. S. (2020). North American birds require mitigation and adaptation to reduce vulnerability to climate change. Conservation Science and Practice, 2(8), e242. https://doi.org/10.1111/csp2.242

BC Government. (2022). BC Cumulative Effects Framework – Human Disturbance – Archived [Data set]. Government of British Columbia. https://catalogue.data.gov.bc.ca/dataset/bc-cumulative-effects-framework-human-disturbance-archived

BC Government. (2023). Old growth maps [Data set]. Government of British Columbia. https://www2.gov.bc.ca/gov/content/industry/forestry/managing-our-forest-resources/old-growth-forests/old-growth-maps

Campbell, E., Wang, T., Raymundo Sanchez, A. A. P.& Stralberg, D. (2025). Velocity-based macrorefugia indices for Canadian tree species [Dataset]. Zenodo. https://doi.org/10.5281/zenodo.14681689 

Carroll, C. (2023). Velocity of climate change for North America based on CMIP6 GCMs [Data set]. Zenodo. https://doi.org/10.5281/zenodo.10631706

Carroll, C., Lawler, J. J., Roberts, D. R., & Hamann, A. (2015). Biotic and climatic velocity identify contrasting areas of vulnerability to climate change. PLOS ONE, 10(10), e0140486. https://doi.org/10.1371/journal.pone.0140486

IPCC. (2023) Climate Change 2023: Synthesis Report. doi: https://doi.org/10.59327/IPCC/AR6-9789291691647

Kehm, G. (2023). Topography-based metrics for climate-change microrefugia: topodiversity, glaciers, wetlands, cool slopes in British Columbia (Version 1) [Dataset]. Zenodo. https://doi.org/10.5281/zenodo.14708618 

Kehm, G. (2026). Topography-based metrics for climate-change microrefugia: topodiversity, glaciers, wetlands, cool slopes in British Columbia (Version 2.1) [Dataset]. Zenodo. https://doi.org/10.5281/zenodo.20129261 

Kuntzemann, C., Whitman, E., Lewis, D., & Stralberg, D. (2025a). Data to support fire refugia analyses in forested British Columbia, Canada [Dataset]. Zenodo. https://doi.org/10.5281/zenodo.16539967 

Kuntzemann, Christine E., Ellen Whitman, Doug Lewis, and Diana Stralberg. 2025. Climate, Topography, or Fuels? Top-Down versus Bottom-Up Controls on Fire Refugia across British Columbia, Canada. Ecosphere 16(9): e70385. https://doi.org/10.1002/ecs2.70385 

Raymundo Sanchez, A. A. P., Bateman, B., & Stralberg, D. (2025b). Macrorefugia indices for North American avifauna [Data set]. Zenodo. https://doi.org/10.5281/zenodo.14658236

Raymundo, A., Stolar, J., Kehm, G., & Stralberg, D. (2026). Climate-change macrorefugia for rare species in British Columbia (backward and forward refugia, 2050s–2080s) [Data set]. Zenodo. https://doi.org/10.5281/zenodo.20785381

Sang, Z., Hethcoat, M., & Stralberg, D. (2025a). Thermal sensitivity of western Canadian ecosystems: A remote-sensing based vulnerability analysis [Data set]. Zenodo. https://doi.org/10.5281/zenodo.14630422

Sang, Z., Robitaille, A. L.& Stralberg, D. (2025b). Drought sensitivity of Canadian forest ecosystems: a remote-sensing based vulnerability analysis [Dataset]. Zenodo. https://doi.org/10.5281/zenodo.14630325 

Stolar, J., Stralberg, D., Raymundo, A., Naujokaitis-Lewis, I., & Nielsen, S. E. (2026). Ecological niche models for British Columbia's rare species (Red-, Blue-, and SARA-listed): Climate normal and future (2050s & 2080s) distributions [Data set]. Zenodo. https://doi.org/10.5281/zenodo.19081408

Funding and acknowledgements

We gratefully acknowledge financial support from the BC Conservation Fund, Environment and Climate Change Canada, the Province of British Columbia through the Ministry of Water, Land and Resource Stewardship and the Ministry of Environment and Climate Change Strategy, the BC Parks Living Lab for Climate Change and Conservation, and the Wilburforce Foundation. In-kind contributions were provided by Natural Resources Canada (Canadian Forest Service).

Disclaimer

The University of Alberta (UofA) is furnishing this deliverable "as is." UofA provides no warranty regarding the contents of the deliverable, whether express, implied, or statutory, including warranties of merchantability, fitness for a particular purpose, or that the contents will be error-free.