TY - JOUR
T1 - A three‐dimensional synthesis study of δ18O in atmospheric CO2 2. Simulations with the TM2 transport model
AU - Ciais, P.
AU - Tans, P.P.
AU - Denning, A.S.
AU - Francey, R.J.
AU - Trolier, M.
AU - Meijer, H.A.J.
AU - White, J.W.C.
AU - Berry, J.A.
AU - Randall, D.A.
AU - Collatz, G.J.
AU - Sellers, P.J.
AU - Monfray, P.
AU - Heimann, M.
N1 - Relation: http://www.agu.org/
Rights: American Geophysical Union
PY - 1997
Y1 - 1997
N2 - In this study, using a three-dimensional (3-D) tracer modeling approach, we simulate the delta(18)O of atmospheric CO2. In the atmospheric transport model TM2 we prescribe the surface fluxes of O-18 due to vegetation and soils, ocean exchange, fossil emissions, and biomass burning. The model simulations are first discussed for each reservoir separately, then all the reservoirs are combined to allow a comparison with the atmospheric delta(18)O measurements made by the National Oceanic and Atmospheric Administration-University of Colorado, Scripps Institution of Oceanography-Centrum Voor Isotopen Onderzoek (United States-Netherlands) and Commonwealth Scientific and Industrial Research Organisation (Australia) air sampling programs, Insights into the latitudinal differences and into the seasonal cycle of delta(18)O in CO2 are gained by looking at the contribution of each source, The isotopic exchange with soils induces a large isotopic depletion over the northern hemisphere continents, which overcomes the concurrent effect of isotopic enrichment due to leaf exchange, Compared to the land biota, the ocean fluxes and the anthropogenic CO2 source have a relatively minor influence, The shape of the latitudinal profile in delta(18)O appears determined primarily by the respiration of the land biota, which balances photosynthetic uptake over the course of a year, Additional information on the phasing of the terrestrial carbon exchange comes from the seasonal cycle of delta(18)O at high northern latitudes.
AB - In this study, using a three-dimensional (3-D) tracer modeling approach, we simulate the delta(18)O of atmospheric CO2. In the atmospheric transport model TM2 we prescribe the surface fluxes of O-18 due to vegetation and soils, ocean exchange, fossil emissions, and biomass burning. The model simulations are first discussed for each reservoir separately, then all the reservoirs are combined to allow a comparison with the atmospheric delta(18)O measurements made by the National Oceanic and Atmospheric Administration-University of Colorado, Scripps Institution of Oceanography-Centrum Voor Isotopen Onderzoek (United States-Netherlands) and Commonwealth Scientific and Industrial Research Organisation (Australia) air sampling programs, Insights into the latitudinal differences and into the seasonal cycle of delta(18)O in CO2 are gained by looking at the contribution of each source, The isotopic exchange with soils induces a large isotopic depletion over the northern hemisphere continents, which overcomes the concurrent effect of isotopic enrichment due to leaf exchange, Compared to the land biota, the ocean fluxes and the anthropogenic CO2 source have a relatively minor influence, The shape of the latitudinal profile in delta(18)O appears determined primarily by the respiration of the land biota, which balances photosynthetic uptake over the course of a year, Additional information on the phasing of the terrestrial carbon exchange comes from the seasonal cycle of delta(18)O at high northern latitudes.
U2 - 10.1029/96JD02361
DO - 10.1029/96JD02361
M3 - Article
SN - 2169-8996
VL - 102
SP - 5873
EP - 5883
JO - Journal of Geophysical Research D
JF - Journal of Geophysical Research D
IS - 5
ER -