This page contains definitions to commonly used terms within the work of the Vulnerability Committee.


Adaptation is an adjustment in natural or human systems in response to actual or expected climatic changes, which moderates harm or exploits beneficial opportunities.

Climate change

Climate change is any systematic change in the long-term statistics of climate elements (such as temperature, pressure, or winds) sustained over several decades or longer. Climate change may be due to natural external forcings, such as changes in solar emission or slow changes in the earth's orbital elements; natural internal processes of the climate system; or anthropogenic forcing.

Engineering vulnerability

Engineering vulnerability is defined as the shortfall in the ability of public infrastructure to absorb the negative effects, and benefit from the positive effects, of changes in the climate conditions used to design and operate infrastructure.

Vulnerability is a function of:

  1. Character, magnitude and rate of change in the climatic conditions to which infrastructure is predicted to be exposed;
  2. Sensitivities of infrastructure to the changes, in terms of positive or negative consequences of changes in applicable climatic conditions; and
  3. Built-in capacity of infrastructure to absorb any net negative consequences from the predicted changes in climatic conditions.

Vulnerability assessment will, therefore, require assessment of all three elements above.

Engineering vulnerability to climate change

Engineering vulnerability to climate change is defined as the level of risk of destruction, disruption or deterioration of engineered public infrastructure resulting from changes in the climatic conditions used to establish the engineering design and operational elements and tolerances for the public infrastructure.


Mitigation is an intervention to reduce the sources or enhance the sinks for greenhouse gases that are a driver for climatic change. This strategy is used to slow the rate of climatic change.

Public Infrastructure

Public Infrastructure is defined as those facilities, networks and assets operated for the collective public benefit including the health, safety, cultural or economic well-being of Canadians, whether operated by government and/or non-government agencies.


Resilience is defined as the ability of a system, community or society exposed to hazards to resist, absorb, accommodate to and recover from the effects of a hazard in a timely and efficient manner, including through the preservation and restoration of its essential basic structures and functions.


Vulnerability is the degree to which a system is susceptible to, or unable to cope with, adverse effects of climate, including climate variability and extremes. It is a function of the character, magnitude and rate of climate variation to which a system is exposed, its sensitivity, and its adaptive capacity.