Terrestrial carbon storage during the past 200 years: A Monte Carlo Analysis of CO2 data from ice core and atmospheric measurements ...

• Main Authors: Bruno, Michele, Joos, Fortunat
• Format: Article in Journal/Newspaper
• Language: English
• Published: University of Bern 1997
• Subjects: ice core
• Online Access: https://dx.doi.org/10.48350/158805; https://boris-portal.unibe.ch/handle/20.500.12422/43408

We have updated earlier deconvolution analyses using most recent high-precision ice core data for the last millennium [Etheridge et al., 1996] and direct atmospheric CO2 observations starting in 1958 [Keeling and Whorf, 1994]. We interpreted nonfossil emissions, that is, the difference between the increase in observed atmospheric plus modeled oceanic carbon inventory and fossil emissions, as biospheric carbon storage (release). We have assessed uncertainties in the CO2 ice core data using a Monte Carlo approach and found a 2-σ uncertainty for the nonfossil emissions (20-year averages) of 0.2–0.4 GtC yr−1. Overall uncertainties of the nonfossil emissions were estimated to be 0.5 GtC yr−1 before 1950 and ˜1 GtC yr−1 during the last decade. We found a large and rapid change of −0.8 GtC yr−1 in the nonfossil emissions (approximate net air-biota flux) between 1933 and 1943. Before 1933, the land biota acted as carbon source of order 0.5 GtC yr−1 in agreement with independent estimates of carbon emissions by land ...