Biases in regional carbon budgets from covariation of surface fluxes and weather in transport model inversions
Recent advances in atmospheric transport model inversions could significantly reduce uncertainties in land carbon uptake through the assimilation of CO<sub>2</sub> concentration measurements at weekly and shorter timescales. The potential of these measurements for reducing biases in esti...
| Main Authors: | , , , , |
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| Format: | Article |
| Language: | English |
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Copernicus Publications
2014-02-01
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| Series: | Atmospheric Chemistry and Physics |
| Online Access: | http://www.atmos-chem-phys.net/14/1571/2014/acp-14-1571-2014.pdf |
| _version_ | 1818050318152237056 |
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| author | I. N. Williams W. J. Riley M. S. Torn S. C. Biraud M. L. Fischer |
| author_facet | I. N. Williams W. J. Riley M. S. Torn S. C. Biraud M. L. Fischer |
| author_sort | I. N. Williams |
| collection | DOAJ |
| description | Recent advances in atmospheric transport model inversions could significantly
reduce uncertainties in land carbon uptake through the assimilation of CO<sub>2</sub>
concentration measurements at weekly and shorter timescales. The potential
of these measurements for reducing biases in estimated land carbon sinks
depends on the strength of covariation between surface fluxes and atmospheric
transport at these timescales and how well transport models represent this
covariation. Daily to seasonal covariation of surface fluxes and atmospheric
transport was estimated in observations at the US Southern Great Plains
Atmospheric Radiation Measurement Climate Research Facility, and compared to
an atmospheric transport model inversion (CarbonTracker). Covariation of
transport and surface fluxes was stronger in CarbonTracker than in
observations on synoptic (daily to weekly) timescales, with a wet year
(2007) having significant covariation compared to a dry year (2006).
Differences between observed and CarbonTracker synoptic covariation resulted
in a 0.3 ppm CO<sub>2</sub> enhancement in boundary layer concentrations during the
growing season, and a corresponding enhancement in carbon uptake by 13% of
the seasonal cycle amplitude in 2007, as estimated by an offline simplified
transport model. This synoptic rectification of surface flux variability was
of similar magnitude to the interannual variability in carbon sinks alone,
and indicates that interannual variability in the inversions can be affected
by biases in simulated synoptic rectifier effects. The most significant
covariation of surface fluxes and transport had periodicities of 10 days and
greater, suggesting that surface flux inversions would benefit from improved
simulations of the effects of soil moisture on boundary layer heights and
surface CO<sub>2</sub> fluxes. Soil moisture remote sensing could be used along with
CO<sub>2</sub> concentration measurements to further constrain atmospheric transport
model inversions. |
| first_indexed | 2024-12-10T10:51:34Z |
| format | Article |
| id | doaj.art-58a959a22bfc4e44a6f48dea5b576fa1 |
| institution | Directory Open Access Journal |
| issn | 1680-7316 1680-7324 |
| language | English |
| last_indexed | 2024-12-10T10:51:34Z |
| publishDate | 2014-02-01 |
| publisher | Copernicus Publications |
| record_format | Article |
| series | Atmospheric Chemistry and Physics |
| spelling | doaj.art-58a959a22bfc4e44a6f48dea5b576fa12022-12-22T01:51:59ZengCopernicus PublicationsAtmospheric Chemistry and Physics1680-73161680-73242014-02-011431571158510.5194/acp-14-1571-2014Biases in regional carbon budgets from covariation of surface fluxes and weather in transport model inversionsI. N. Williams0W. J. Riley1M. S. Torn2S. C. Biraud3M. L. Fischer4Lawrence Berkeley National Laboratory, Earth Sciences Division, Berkeley, CA, USALawrence Berkeley National Laboratory, Earth Sciences Division, Berkeley, CA, USALawrence Berkeley National Laboratory, Earth Sciences Division, Berkeley, CA, USALawrence Berkeley National Laboratory, Earth Sciences Division, Berkeley, CA, USALawrence Berkeley National Laboratory, Environmental Energy Technologies Division, Berkeley, CA, USARecent advances in atmospheric transport model inversions could significantly reduce uncertainties in land carbon uptake through the assimilation of CO<sub>2</sub> concentration measurements at weekly and shorter timescales. The potential of these measurements for reducing biases in estimated land carbon sinks depends on the strength of covariation between surface fluxes and atmospheric transport at these timescales and how well transport models represent this covariation. Daily to seasonal covariation of surface fluxes and atmospheric transport was estimated in observations at the US Southern Great Plains Atmospheric Radiation Measurement Climate Research Facility, and compared to an atmospheric transport model inversion (CarbonTracker). Covariation of transport and surface fluxes was stronger in CarbonTracker than in observations on synoptic (daily to weekly) timescales, with a wet year (2007) having significant covariation compared to a dry year (2006). Differences between observed and CarbonTracker synoptic covariation resulted in a 0.3 ppm CO<sub>2</sub> enhancement in boundary layer concentrations during the growing season, and a corresponding enhancement in carbon uptake by 13% of the seasonal cycle amplitude in 2007, as estimated by an offline simplified transport model. This synoptic rectification of surface flux variability was of similar magnitude to the interannual variability in carbon sinks alone, and indicates that interannual variability in the inversions can be affected by biases in simulated synoptic rectifier effects. The most significant covariation of surface fluxes and transport had periodicities of 10 days and greater, suggesting that surface flux inversions would benefit from improved simulations of the effects of soil moisture on boundary layer heights and surface CO<sub>2</sub> fluxes. Soil moisture remote sensing could be used along with CO<sub>2</sub> concentration measurements to further constrain atmospheric transport model inversions.http://www.atmos-chem-phys.net/14/1571/2014/acp-14-1571-2014.pdf |
| spellingShingle | I. N. Williams W. J. Riley M. S. Torn S. C. Biraud M. L. Fischer Biases in regional carbon budgets from covariation of surface fluxes and weather in transport model inversions Atmospheric Chemistry and Physics |
| title | Biases in regional carbon budgets from covariation of surface fluxes and weather in transport model inversions |
| title_full | Biases in regional carbon budgets from covariation of surface fluxes and weather in transport model inversions |
| title_fullStr | Biases in regional carbon budgets from covariation of surface fluxes and weather in transport model inversions |
| title_full_unstemmed | Biases in regional carbon budgets from covariation of surface fluxes and weather in transport model inversions |
| title_short | Biases in regional carbon budgets from covariation of surface fluxes and weather in transport model inversions |
| title_sort | biases in regional carbon budgets from covariation of surface fluxes and weather in transport model inversions |
| url | http://www.atmos-chem-phys.net/14/1571/2014/acp-14-1571-2014.pdf |
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