Climatic Warming History from Inversions of Temperature Logs

Recent projects have been dealing with studies of ground warming histories from the inversions of precise temperature logs from wells across western Canada. Logging of temperature has been done in over 80 wells spread throughout the western Canada basin and the Williston basin. In the last century, average warming magnitude was 1.9 K. Repeated logs that have been done over the last decade revealed 0.1-0.3 K relative change of ground surface temperature. Across Cananda, studies of the patterns of ground warming are under way. The east to west retardation in the onset of the recent warming across Canada inferred from inversions of temperature logs was recently studied (Majorowicz, Safanda, and Skinner 2002 Journal of Geophysical Research, Solid State, V.107, B10, 2227, doi:10.1029/2001JB000519.2002)

Recently large ground warming in the Canadian Arctic was inferred from inversions of temperature logs and compared with other proxy climate reconstructions. Warming as high as 2 C was found to be commonly occurring since the late 1700s untill the mid-twentieth century followed by cooling in the 1960s and 1970s. The results are to be published by Pure and Applied Geophysics (accepted in 2003) and Earth and Planetary Science Letters (2004).

FIG. 1.

Ground Warming Magnitudes (K) in the Canadian Prarie Provinces Derived From Temperature Versus Depth Profiles, Majorowicz and Skinner, Climatic Research, Vol. 16, No. 3, 157-167, 2001

FIG. 2, a-c

Warming and Cooling Patterns throughout the last four centuries across Canada derived from FSI inversions of temperature logs in wells. Well sites are shown by triangles. East to west retardation of the onset of recent warming has been observed (JGR 2002, Vol. 107, No. B10. 2227, doi:10.1029/2001JB000519, 2002).