HR: 17:00h
AN: PP54A-05 [Abstracts]
TI: Divergence in ringwidth Chronologies from the Yukon Territory, Canada
AU: * Luckman, B H
EM: luckman@uwo.ca
AF: Department of Geography, The University of Western Ontario, London, ONT N6A5C2,
Canada
AU: Earles, S
EM: searles2@uwo.ca
AF: Department of Geography, The University of Western Ontario, London, ONT N6A5C2,
Canada
AU: Morimoto, D
EM: dmorimot@uwo.ca
AF: Department of Geography, The University of Western Ontario, London, ONT N6A5C2,
Canada
AU: Watson, E
EM: emma.watson@rogers.com
AF: Department of Geography, The University of Western Ontario, London, ONT N6A5C2,
Canada
AU: Kenigsberg, M
EM: mkenigs@uwo.ca
AF: Department of Geography, The University of Western Ontario, London, ONT N6A5C2,
Canada
AB:
A new tree-ring chronology database has been developed across the Yukon and northern British Columbia that
includes almost 100 upper elevation white spruce chronologies and over 20 new subalpine fir chronologies that
extend into the present century. These include approximately 20 sites along the Dempster Highway that bracket
the position of the TTHH site where divergence was initially recognized. Preliminary results indicate a mixed
response in regional chronology patterns. The dominant pattern (in both spruce and fir) shows maximum 20th
century growth in the 1930—50 interval with lower and/or declining values in the late 20th century although some
chronologies in the southwest show highest growth in the late 20th century The strongest correlations of
ringwidth series from sites along the Dempster Highway with Dawson temperatures show inverse relationships
with summer (JJA) and/or June July temperatures in the two years prior to the growth year although residual
chronologies at a few sites do show a summer temperature signal. These results suggest current relationships
with climate are complex and may reflect local site and or microclimate conditions as well as larger scale climatic
controls. Investigation of changing response to temperatures over the 20th century are ongoing will be reported
at the meeting.
DE: 1600 GLOBAL CHANGE
DE: 1626 Global climate models (3337, 4928)
SC: Paleoceanography and Paleoclimatology [PP]
MN: 2007 Fall Meeting