Drivers of column-average CO_2 variability at Southern Hemispheric Total Carbon Column Observing Network sites
Creators
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1.
University of Wollongong
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2.
University of Bremen
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3.
Laboratoire des Sciences du Climat et de l'Environnement
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4.
University of the Philippines Diliman
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California Institute of Technology
Abstract
We investigate factors that drive the variability in total column CO_2 at the Total Carbon Column Observing Network sites in the Southern Hemisphere using fluxes tagged by process and by source region from the CarbonTracker analysed product as well as the Simple Biosphere model. We show that the terrestrial biosphere is the largest driver of variability in the Southern Hemisphere column CO_2. However, it does not dominate in the same fashion as in the Northern Hemisphere. Local- and hemispheric-scale biomass burning can also play an important role, particularly at the tropical site, Darwin. The magnitude of seasonal variability in the column-average dry-air mole fraction of CO_2, X_CO_2, is also much smaller in the Southern Hemisphere and comparable in magnitude to the annual increase. Comparison of measurements to the model simulations highlights that there is some discrepancy between the two time series, especially in the early part of the Darwin data record. We show that this mismatch is most likely due to erroneously estimated local fluxes in the Australian tropical region, which are associated with enhanced photosynthesis caused by early rainfall during the tropical monsoon season.
Additional Information
© Author(s) 2014. This work is distributed under the Creative Commons Attribution 3.0 License. Received: 10 April 2013; Published in Atmos. Chem. Phys. Discuss.: 3 June 2013; Revised: 22 July 2014; Accepted: 13 August 2014; Published: 18 September 2014. TCCON is funded by grant NNX11AG01G from NASA's Carbon Cycle Science Program. Measurements at Darwin are supported by Australian Research Council grant DP0879468 and NASA's Orbiting Carbon Observatory Project. The Lauder TCCON programme and TM3 model simulations are funded by NIWA under the New Zealand Greenhouse Gas Emissions, Mitigation, and Carbon Cycle Science Programme, and under the NZ Foundation of Research Science and Technology contracts C01X0204 and COX10406. CarbonTracker 2011_oi results provided by NOAA ESRL, Boulder, Colorado, USA from the website at http://carbontracker.noaa.gov. This work was also made possible by an RSNZ ISAT bilateral exchange grant and by grants from the Australian Research Council and Department of Innovation, Industry, Science and Research International Science Linkages project CG130014. Support for this work was also provided by the ESA GHG-CCI project. We gratefully acknowledge operational assistance from staff at the ARM site in Darwin. The authors acknowledge the constructive input of the two anonymous referees, whose feedback resulted in a much improved manuscript. Edited by: T. RöckmannAttached Files
Published - acp-14-9883-2014.pdf
Files
acp-14-9883-2014.pdf
Additional details
Additional titles
- Alternative title
- Drivers of column-average CO2 variability at Southern Hemispheric Total Carbon Column Observing Network sites
Identifiers
- Eprint ID
- 50586
- Resolver ID
- CaltechAUTHORS:20141020-161537740
Funding
- NASA
- NNX11AG01G
- Australian Research Council
- DP0879468
- NIWA New Zealand Greenhouse Gas Emissions, Mitigation, and Carbon Cycle Science Programme
- New Zealand Foundation of Research Science and Technology
- C01X0204
- New Zealand Foundation of Research Science and Technology
- COX10406
- RSNZ ISAT bilateral exchange grant
- Department of Innovation, Industry, Science and Research (Australia)
- CG130014
Dates
- Created
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2014-10-21Created from EPrint's datestamp field
- Updated
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2021-11-10Created from EPrint's last_modified field
Caltech Custom Metadata
- Caltech groups
- Division of Geological and Planetary Sciences (GPS)