摘要:West Siberia contains the largest extent of wetlands in the world, including large peat
deposits; the wetland area is equivalent to 27% of the total area of West Siberia. This study
used inverse modeling to refine emissions estimates for West Siberia using atmospheric
CH4 observations and
two wetland CH4 emissions inventories: (1) the global wetland emissions dataset of the NASA Goddard
Institute for Space Studies (the GISS inventory), which includes emission seasons and
emission rates based on climatology of monthly surface air temperature and precipitation,
and (2) the West Siberian wetland emissions data (the Bc7 inventory), based on in situ flux
measurements and a detailed wetland classification. The two inversions using the GISS and
Bc7 inventories estimated annual mean flux from West Siberian wetlands to be
2.9 ± 1.7 and
3.0 ± 1.4 Tg yr − 1, respectively, which
are lower than the 6.3 Tg yr − 1 predicted in the GISS inventory, but similar to those of the Bc7 inventory (3.2 Tg yr − 1). The well-constrained monthly fluxes and a comparison between the predicted
CH4 concentrations in the two inversions suggest that the Bc7
inventory predicts the seasonal cycle of West Siberian wetland
CH4 emissions more reasonably, indicating that the GISS inventory predicts more emissions
from wetlands in northern and middle taiga.