National Synthesis of Environmental Change

Activity Rationale

In order to predict how present changes in climate will affect Canada's environment, it is essential to understand the environmental impacts of past climate changes. In this activity, paleogeographic data from the last 18,000 years are assembled, synthesized, published, and web-enabled to help guide climate change adaptation strategies.

Leader: Stephen Wolfe

The Topic

Understanding the natural variability of the climate-environment system is essential for assessing present changes in climate associated with human activities. Of particular interest are the changes in climate over the last 18,000 years, from the Last Glacial Maximum (the period during the last ice age when the ice was at maximum extent) to the present. This activity displays some of the environmental consequences of past climate change that have occurred in North America since the Last Glacial Maximum. Products from this activity will include:

• A synthesis of postglacial changes in sea- and lake-levels

• Maps showing postglacial crustal warping

• Updated databases on permafrost history, eolian history, wetland history, and sea-ice history.  

Maps of North America created by querying the Interactive Map Viewer. The top map shows the extent of glaciations that occurred in North America 18,000 years ago (white represents ice, blue represents water, and grey represents land). The bottom map shows the vegetation that would have occurred during this time.

Results

Reconstructions are provided at the web-link below for two series of maps, with each map representing a point in time (e.g., 10 000 years ago). Each map series is briefly described by an abstract. The maps may be viewed and manipulated using the software provided on the site. The underlying scientific databases and literature sources may be accessed by querying the site symbols on the maps. The symbols represent sites for which published data and interpretations are available. We intend to post updates of these maps and the databases as significant amounts of new data become available.

Although a wider selection of reconstructions will eventually be provided, the site currently contains a sequence of maps displaying (1) deglaciation and associated changes in land, sea, and lake areas, and (2) changes in the distribution of terrestrial biomes during deglaciation. Future maps series will display isobases of crustal rebound (change of elevation), marine molluscan zones and marine mammal distributions, and archaeological site distributions.

Present map series include Deglaciation of North America and Vegetation History, Glaciated North America. Please access the web link below to view these interactive maps.

Activities

• Deglaciation of North America

   

  • Abstract

     

  • Interactive map viewer

    

     

    1,000 years BP2,000 years BP3,000 years BP4,000 years BP5,000 years BP5,500 years BP6,000 years BP6,500 years BP7,000 years BP7,200 years BP7,600 years BP7,700 years BP7,800 years BP8,000 years BP8,500 years BP9,000 years BP9,500 years BP9,600 years BP10,000 years BP10,250 years BP10,500 years BP11,000 years BP11,500 years BP12,000 years BP12,500 years BP13,000 years BP13,500 years BP14,000 years BP14,500 years BP15,000 years BP15,500 years BP16,000 years BP16,500 years BP17,000 years BP17,500 years BP18,000 years BP

     

   

• Vegetation History, Glaciated North America

   

  • Abstract

     

  • Interactive Map Viewer

    

     

    1,000 years BP2,000 years BP3,000 years BP4,000 years BP5,000 years BP6,000 years BP7,000 years BP8,000 years BP9,000 years BP10,000 years BP11,000 years BP12,000 years BP13,000 years BP14,000 years BP18,000 years BP

     

Publications

Please note that subscriptions may be required for access to some articles. To request a copy of publications, or for any more information, please contact Art Dyke.

Check for more recent publications in GEOSCAN, the publications database of the Geological Survey of Canada and the Canada Centre for Remote Sensing.

Dyke, A.S. 2005. Late Quaternary vegetation history of northern North America based on pollen, macrofossil, and faunal remains. Géographie physique et Quaternaire, 2005, vol. 59, nos 2-3, p. 211-262.

Dyke, A.S., 2004. An outline of the deglaciation of North America with emphasis on central and northern Canada, p. 373-424. In J. Ehlers and P.L. Gibbard, ed., Quaternary Glaciations-Extent and Chronology, Part II: North America. Developments in Quaternary Science, Vol. 2b. Elsevier, Amsterdam, 440 p.