Reconstruction of little ice age climate in southwestern Ontario, Canada, from oxygen and hydrogen isotope ratios in tree rings

Oxygen and hydrogen isotopes in wood cellulose from an elm and a maple tree that grew in different hydrological settings are used to reconstruct recent temperature and moisture changes in southwestern Ontario, Canada. Cellulose isotope data and inferred δwater and relative humidity, for the two sites, are compared with recorded (after A.D. 1880) climate data. This provides the basis for the reconstruction of palaeoclimate before A.D. 1880. Evidence here indicates that climate, during the historical end of the Little Ice Age in southwestern Ontario, was characterized by warmer annual temperatures with intervals of dry (A.D. 1610 to 1820) and moist (A.D. 1820 to 1860) annual seasons. This may reflect a change in airmass influence in the Great Lakes region at this time. (author). 40 refs, 2 figs