The Theme
Wind erosion has noticeable effects on agricultural lands and on sand dune areas in many parts of Canada. These effects result in soil and nutrient losses and,
ultimately, in reduced crop yields. A relatively good understanding exists of wind erosion impacts on these unprotected soils under present-day conditions. In
general, the risk is increased when soils are dryer and winds are stronger. Both of these conditions are more likely to occur as the climate warms. This map
shows the projected vulnerability of these areas to climate change.
Sensitivity Projection
This map shows both the projected general patterns and the local details of these patterns. Two variables are being mapped:
- Wind erosion risk. This risk is based on the nature
of local climate and vegetation. Areas with dryer, warmer climates and
with sparse vegetation cover are more vulnerable to wind erosion. The
degree of wind erosion risk is shown on the map by using heavier saturation
of any of the colours (in other words, dark colour shades of any colour
mean a higher wind erosion risk).
- Climate sensitivity. The levels of climate sensitivity
were derived by comparing present and future ecoclimatic regions of
Canada, based on the assumption of a doubling of atmospheric carbon
dioxide concentrations over pre-industrial levels. The projection of
future ecoclimatic regions of Canada was developed by Rizzo and Wiken
(1992). The sensitivity results are shown by types of colour. Areas
in bright colour will have a more substantial shift of their ecoclimatic
region type if the projected carbon dioxide change takes place. For
example, the projected shifts are more pronounced in the southern Prairies
and in the southernmost part of Ontario.
Each of the two variables is divided into four categories to suggest
the severity of risk. The matrix of sixteen possible combinations
of these two valuables is mapped below (Figure 1). Areas of greatest
risk are represented using the most vivid colours, as well as the
heaviest saturation of each colour.
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Figure 1. Sensitivity Matrix
Risk Patterns
The map reveals that the regions that would have the highest sensitivity to a warming climate, as shown in pink and orange, are likely to occur in the southern
and central Prairies and in the southernmost part of Ontario. Within these regions, there is a varying degree of vulnerability to wind erosion risk, depending on
local circumstances. Areas with lowest overall risk are likely those shown in light green, which have a lower climate sensitivity as well as a lower level of wind
erosion risk under the present-day conditions. These areas are found in the northern fringes of the Prairies and in large parts of the agricultural areas of Quebec
and the Maritimes.
Dune sensitivity was also derived based on the potential change
in ecoclimatic conditions. Changes in wind erosion risk of sand
dunes will mainly result from changes in the amount and type of
vegetation cover. Most sand dunes in Canada are rated as having
a low climatic sensitivity because the changes in vegetation cover
are found to have minimal effects on most sand dune activity. The
areas that are sensitive to climate change include the southern
portions of Alberta and Saskatchewan corresponding to a potential
semi-desert ecoclimatic region. Southern Ontario and portions of
the Maritimes, including Prince Edward Island, have moderate to
high sensitivity. Sensitivity declines northward with changes in
climatic and vegetation conditions.
Data Source
This map is an insert to the publication: Wolfe, S.A. and W.G.
Nickling. 1997. Sensitivity of Eolian Processes to Climate Change
in Canada. Geological Survey of Canada Bulletin 421. Ottawa: Natural
Resources Canada.
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