Freshwater shelled invertebrate indicators of paleoclimate in northwestern Canada during late glacial times: Discussion

Abstract

The preservation of icy Pleistocene sediments and the lower portions of relic ice wedges beneath a widespread thaw unconformity within 60 km of site 3 of Delorme et al. (1977) suggests a maximum postglacial thaw of only a few meters. Permafrost was present, along the western Arctic Coast, throughout postglacial time. Mean annual ground temperatures have not risen above 0.degree. C except for very brief periods measurable only in years, not centuries. As present mean annual air temperatures in Canada tend to be several degrees colder than mean annual ground temperatures, it seems probable that mean annual air temperatures were several degrees below 0.degree. C during the postulated warm interval 14,410-6820 yr B.P.