Simulations of atmospheric methane for Cape Grim, Tasmania, to constrain southeastern Australian methane emissions
This study uses two climate models and six scenarios of prescribed methane emissions to compare modelled and observed atmospheric methane between 1994 and 2007, for Cape Grim, Australia (40.7° S, 144.7° E). The model simulations follow the TransCom-CH<sub>4</sub>...
| Main Authors: | , , , , , , , |
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| Format: | Article |
| Language: | English |
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Copernicus Publications
2015-01-01
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| Series: | Atmospheric Chemistry and Physics |
| Online Access: | http://www.atmos-chem-phys.net/15/305/2015/acp-15-305-2015.pdf |
| _version_ | 1818539104755777536 |
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| author | Z. M. Loh R. M. Law K. D. Haynes P. B. Krummel L. P. Steele P. J. Fraser S. D. Chambers A. G. Williams |
| author_facet | Z. M. Loh R. M. Law K. D. Haynes P. B. Krummel L. P. Steele P. J. Fraser S. D. Chambers A. G. Williams |
| author_sort | Z. M. Loh |
| collection | DOAJ |
| description | This study uses two climate models and six scenarios of prescribed
methane emissions to compare modelled and observed atmospheric methane
between 1994 and 2007, for Cape Grim, Australia (40.7° S,
144.7° E). The model simulations follow the TransCom-CH<sub>4</sub>
protocol and use the Australian Community Climate and Earth System
Simulator (ACCESS) and the CSIRO Conformal-Cubic Atmospheric Model
(CCAM). Radon is also simulated and used to reduce the impact of
transport differences between the models and observations.
Comparisons are made for air samples that have traversed the
Australian continent. All six emission scenarios give modelled
concentrations that are broadly consistent with those observed. There
are three notable mismatches, however. Firstly, scenarios that
incorporate interannually varying biomass burning emissions produce
anomalously high methane concentrations at Cape Grim at times of large
fire events in southeastern Australia, most likely due to the fire
methane emissions being unrealistically input into the lowest model
level. Secondly, scenarios with wetland methane emissions in the
austral winter overestimate methane concentrations at Cape Grim during
wintertime while scenarios without winter wetland emissions perform
better. Finally, all scenarios fail to represent a~methane source in
austral spring implied by the observations. It is possible that the
timing of wetland emissions in the scenarios is incorrect with recent
satellite measurements suggesting an austral spring (September–October–November),
rather than winter, maximum for wetland emissions. |
| first_indexed | 2024-12-11T21:37:39Z |
| format | Article |
| id | doaj.art-6618a5e488b64a5a946b218a1da18fea |
| institution | Directory Open Access Journal |
| issn | 1680-7316 1680-7324 |
| language | English |
| last_indexed | 2024-12-11T21:37:39Z |
| publishDate | 2015-01-01 |
| publisher | Copernicus Publications |
| record_format | Article |
| series | Atmospheric Chemistry and Physics |
| spelling | doaj.art-6618a5e488b64a5a946b218a1da18fea2022-12-22T00:49:58ZengCopernicus PublicationsAtmospheric Chemistry and Physics1680-73161680-73242015-01-0115130531710.5194/acp-15-305-2015Simulations of atmospheric methane for Cape Grim, Tasmania, to constrain southeastern Australian methane emissionsZ. M. Loh0R. M. Law1K. D. Haynes2P. B. Krummel3L. P. Steele4P. J. Fraser5S. D. Chambers6A. G. Williams7Centre for Australian Weather and Climate Research, CSIRO Oceans and Atmosphere Flagship, Private Bag 1, Aspendale, Vic 3195, AustraliaCentre for Australian Weather and Climate Research, CSIRO Oceans and Atmosphere Flagship, Private Bag 1, Aspendale, Vic 3195, AustraliaCentre for Australian Weather and Climate Research, CSIRO Oceans and Atmosphere Flagship, Private Bag 1, Aspendale, Vic 3195, AustraliaCentre for Australian Weather and Climate Research, CSIRO Oceans and Atmosphere Flagship, Private Bag 1, Aspendale, Vic 3195, AustraliaCentre for Australian Weather and Climate Research, CSIRO Oceans and Atmosphere Flagship, Private Bag 1, Aspendale, Vic 3195, AustraliaCentre for Australian Weather and Climate Research, CSIRO Oceans and Atmosphere Flagship, Private Bag 1, Aspendale, Vic 3195, AustraliaAustralian Nuclear Science and Technology Organisation, Locked Bag 2001, Kirrawee DC, NSW 2232, AustraliaAustralian Nuclear Science and Technology Organisation, Locked Bag 2001, Kirrawee DC, NSW 2232, AustraliaThis study uses two climate models and six scenarios of prescribed methane emissions to compare modelled and observed atmospheric methane between 1994 and 2007, for Cape Grim, Australia (40.7° S, 144.7° E). The model simulations follow the TransCom-CH<sub>4</sub> protocol and use the Australian Community Climate and Earth System Simulator (ACCESS) and the CSIRO Conformal-Cubic Atmospheric Model (CCAM). Radon is also simulated and used to reduce the impact of transport differences between the models and observations. Comparisons are made for air samples that have traversed the Australian continent. All six emission scenarios give modelled concentrations that are broadly consistent with those observed. There are three notable mismatches, however. Firstly, scenarios that incorporate interannually varying biomass burning emissions produce anomalously high methane concentrations at Cape Grim at times of large fire events in southeastern Australia, most likely due to the fire methane emissions being unrealistically input into the lowest model level. Secondly, scenarios with wetland methane emissions in the austral winter overestimate methane concentrations at Cape Grim during wintertime while scenarios without winter wetland emissions perform better. Finally, all scenarios fail to represent a~methane source in austral spring implied by the observations. It is possible that the timing of wetland emissions in the scenarios is incorrect with recent satellite measurements suggesting an austral spring (September–October–November), rather than winter, maximum for wetland emissions.http://www.atmos-chem-phys.net/15/305/2015/acp-15-305-2015.pdf |
| spellingShingle | Z. M. Loh R. M. Law K. D. Haynes P. B. Krummel L. P. Steele P. J. Fraser S. D. Chambers A. G. Williams Simulations of atmospheric methane for Cape Grim, Tasmania, to constrain southeastern Australian methane emissions Atmospheric Chemistry and Physics |
| title | Simulations of atmospheric methane for Cape Grim, Tasmania, to constrain southeastern Australian methane emissions |
| title_full | Simulations of atmospheric methane for Cape Grim, Tasmania, to constrain southeastern Australian methane emissions |
| title_fullStr | Simulations of atmospheric methane for Cape Grim, Tasmania, to constrain southeastern Australian methane emissions |
| title_full_unstemmed | Simulations of atmospheric methane for Cape Grim, Tasmania, to constrain southeastern Australian methane emissions |
| title_short | Simulations of atmospheric methane for Cape Grim, Tasmania, to constrain southeastern Australian methane emissions |
| title_sort | simulations of atmospheric methane for cape grim tasmania to constrain southeastern australian methane emissions |
| url | http://www.atmos-chem-phys.net/15/305/2015/acp-15-305-2015.pdf |
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