Summary

These scenarios may be more palatable to policy and decision-makers as they appear to have a

greater Ňgrounding” in reality; they have been experienced in the past. However, the

magnitude and types of changes that may be expected as a result of climate change have not

been experienced during recorded history, making it difficult to find appropriate analogues.  

A.3 Systematic Changes to Climate Parameters

In this technique, scenarios are developed by making systematic changes to observed climate

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data, for example, 1 or 2 or 3  C temperature increase or  10 % or  20 % precipitation change

or other factors such as lake levels.  These scenarios are developed with guidance from GCMs

(e.g. limits of temperature changes) or stakeholder-specified vulnerabilities.  These scenarios

are often considered very simplistic representations of the complex response of the climate

system.  However, they can provide a preliminary exploration of critical thresholds or

changes in a Ňsensitivity analysis”.  If warranted, more detailed scenario development and

impact analysis can follow.

References

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http://www.cics.uvic.ca/index.cgi?/About_Us/Canadian_Institute_for_Climate_Studies

CCIS. (Canadian Climate Impacts Scenarios Project). 2002.  

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