Case studies

Assessing Vulnerabilities: Future Scenarios for Forest Ecosystem and Disturbance Patterns

The next step in the decision process was to set out the potential implication of future climate change on ecosystem management in Mt. Robson Park. The focus here was on potential climate change scenarios for three of the most significant factors impacting final management objectives: Forest ecosystems; Mountain pine beetle disturbance; and, Wildfire disturbance.

The approach to determine each of the three future scenarios began with a review of the general state of knowledge. Key trends (and uncertainties) were then developed based on the climate change scenarios described in the previous section. Depending on the availability of information, the tools and techniques applied to determine these scenarios range from:

  •  Inferring results from research conducted in similar circumstances

  •  Extrapolating results from broader provincial-scale assessments

  •  Applying subjective professional judgments.

The intent was not to undertaken comprehensive predictive modeling of forest ecosystem and disturbance regimes in the Park under conditions of climate change. Care was taken to highlight many of the challenges to be faced in applying global climate change scenario predictions to scale-dependent questions such as forest evolution in a mountainous region. This approach can be described as a “multiple lines of evidence” approach. It is expected to be common among climate change adaptation practitioners faced with addressing multiple, inter-related planning issues.

The table below provides a summary of the key long-term trends and key uncertainties in forest ecosystem and disturbance scenarios for Mt. Robson Park.

Table 6: Summary of forest ecosystem and disturbance scenarios

Issue Key Long-term Trends Confidence Major Uncertainties
Forest Ecosystems Increase in forested area, with ICH, SBS and ESSF subzones all migrating to higher elevations. Decrease in the AT zone. Very Likely The rate of change.
The extent to which ICH replaces SBS.
Increase in climatically suitable habitat for lodgepole pine and western red cedar. Likely The extent to which tree species are able to utilize new habitat.
MPB Disturbance Increase in climate suitability for the mountain pine beetle. Very Likely The rate of change.
Increase in the probability of major outbreaks. Possible The frequency of future outbreaks, which will be increasingly determined by host availability.
Fire Disturbance Increase in high fire weather indexes. Likely The rate of change.
Future fire season precipitation.
Increase in the probability of major fires. Possible The extent of changes to ecosystems zones (SBS has a shorter fire return interval), tree species, and major MPB outbreak frequency.

**Note: The subjective confidence rating scales are based on UKCIP framework guidance as follows. Virtually certain (>99%), Very likely (90-99%), Likely (66-90%), Possible (33-66).

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