Climate and atmospheric drivers of historical terrestrial carbon uptake in the province of British Columbia, Canada
- 1Canadian Centre for Climate Modelling and Analysis, Environment Canada, University of Victoria, Victoria, BC, V8W 2Y2, Canada
- 2Canadian Forest Service, Natural Resources Canada, 506 West Burnside Road, Victoria, BC, V8Z 1M5, Canada
- 3Faculty of Forestry, University of British Columbia, 2424 Main Mall, Vancouver, BC, V6T1Z4, Canada
- 4Centre for Forest Biology, University of Victoria, British Columbia, Canada
- 5Pacific Climate Impacts Consortium, University of Victoria, Victoria, British Columbia, Canada
Abstract. The impacts of climate change and increasing atmospheric CO2 concentration on the terrestrial uptake of carbon dioxide since 1860 in the Canadian province of British Columbia are estimated using the process-based Canadian Terrestrial Ecosystem Model (CTEM). Model simulations show that these two factors yield an enhanced carbon uptake of around 44 gC m−2 yr−1 (or equivalently 63 gC m−2 yr−1 over the province's forested area), during the 1980s and 1990s, and continuing into the 2000s. About three-quarters of the simulated sink enhancement in our study compared to pre-industrial conditions is attributed to changing climate, and the rest is attributed to increase in CO2 concentration. The model response to changing climate and increasing CO2 is corroborated by comparing simulated stem wood growth rates with ground-based measurements from inventory plots in coastal British Columbia. The simulated sink is not an estimate of the net carbon balance because the effects of harvesting, insect disturbances and land-use change are not considered.