Multiscale assessment of North American terrestrial carbon balance
<p>Comparisons of carbon uptake estimates from bottom-up terrestrial biosphere models (TBMs) to top-down atmospheric inversions help assess how well we understand carbon dioxide (CO<span class="inline-formula"><sub>2</sub></span>) exchange between the atmosphe...
| Main Authors: | , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Copernicus Publications
2024-02-01
|
| Series: | Biogeosciences |
| Online Access: | https://bg.copernicus.org/articles/21/869/2024/bg-21-869-2024.pdf |
| _version_ | 1797305139004964864 |
|---|---|
| author | K. T. Foster K. T. Foster W. Sun Y. P. Shiga J. Mao A. M. Michalak A. M. Michalak |
| author_facet | K. T. Foster K. T. Foster W. Sun Y. P. Shiga J. Mao A. M. Michalak A. M. Michalak |
| author_sort | K. T. Foster |
| collection | DOAJ |
| description | <p>Comparisons of carbon uptake estimates from bottom-up terrestrial biosphere models (TBMs) to top-down atmospheric inversions help assess how well we understand carbon dioxide (CO<span class="inline-formula"><sub>2</sub></span>) exchange between the atmosphere and terrestrial biosphere. Previous comparisons have shown varying levels of agreement between bottom-up and top-down approaches, but they have almost exclusively focused on large, aggregated scales (e.g., global or continental), providing limited insights into reasons for the mismatches. Here we explore how consistency, defined as the spread in net ecosystem exchange (NEE) estimates within an ensemble of TBMs or inversions, varies with at finer spatial scales ranging from <span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M2" display="inline" overflow="scroll" dspmath="mathml"><mrow><mn mathvariant="normal">1</mn><msup><mi/><mo>∘</mo></msup><mo>×</mo><mn mathvariant="normal">1</mn><msup><mi/><mo>∘</mo></msup></mrow></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="34pt" height="11pt" class="svg-formula" dspmath="mathimg" md5hash="21fbad4d1955efadb851b48211f1f95d"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="bg-21-869-2024-ie00001.svg" width="34pt" height="11pt" src="bg-21-869-2024-ie00001.png"/></svg:svg></span></span> to the continent of North America. We also evaluate how well consistency informs accuracy in overall NEE estimates by filtering models based on their agreement with the variability, magnitude, and seasonality in observed atmospheric CO<span class="inline-formula"><sub>2</sub></span> drawdowns or enhancements. We find that TBMs produce more consistent estimates of NEE for most regions and at most scales relative to inversions. Filtering models using atmospheric CO<span class="inline-formula"><sub>2</sub></span> metrics causes ensemble spread to decrease substantially for TBMs, but not for inversions. This suggests that ensemble spread is likely not a reliable measure of the uncertainty associated with the North American carbon balance at any spatial scale. Promisingly, applying atmospheric CO<span class="inline-formula"><sub>2</sub></span> metrics leads to a set of models with converging flux estimates across TBMs and inversions. Overall, we show that multiscale assessment of the agreement between bottom-up and top-down NEE estimates, aided by regional-scale observational constraints is a promising path towards identifying fine-scale sources of uncertainty and improving both ensemble consistency and accuracy. These findings help refine our understanding of biospheric carbon balance, particularly at scales relevant for informing regional carbon-climate feedbacks.</p> |
| first_indexed | 2024-03-08T00:20:36Z |
| format | Article |
| id | doaj.art-067132b6299d40d2965c8a992014b26f |
| institution | Directory Open Access Journal |
| issn | 1726-4170 1726-4189 |
| language | English |
| last_indexed | 2024-03-08T00:20:36Z |
| publishDate | 2024-02-01 |
| publisher | Copernicus Publications |
| record_format | Article |
| series | Biogeosciences |
| spelling | doaj.art-067132b6299d40d2965c8a992014b26f2024-02-16T08:23:12ZengCopernicus PublicationsBiogeosciences1726-41701726-41892024-02-012186989110.5194/bg-21-869-2024Multiscale assessment of North American terrestrial carbon balanceK. T. Foster0K. T. Foster1W. Sun2Y. P. Shiga3J. Mao4A. M. Michalak5A. M. Michalak6Department of Global Ecology, Carnegie Institution for Science, Stanford, CA 94305, USADepartment of Earth System Science, Stanford University, Stanford, CA 94305, USADepartment of Global Ecology, Carnegie Institution for Science, Stanford, CA 94305, USAindependent researcher: San Francisco, CA, USAEnvironmental Sciences Division and Climate Change Science Institute, Oak Ridge National Laboratory, Oak Ridge, TN 37830, USADepartment of Global Ecology, Carnegie Institution for Science, Stanford, CA 94305, USADepartment of Earth System Science, Stanford University, Stanford, CA 94305, USA<p>Comparisons of carbon uptake estimates from bottom-up terrestrial biosphere models (TBMs) to top-down atmospheric inversions help assess how well we understand carbon dioxide (CO<span class="inline-formula"><sub>2</sub></span>) exchange between the atmosphere and terrestrial biosphere. Previous comparisons have shown varying levels of agreement between bottom-up and top-down approaches, but they have almost exclusively focused on large, aggregated scales (e.g., global or continental), providing limited insights into reasons for the mismatches. Here we explore how consistency, defined as the spread in net ecosystem exchange (NEE) estimates within an ensemble of TBMs or inversions, varies with at finer spatial scales ranging from <span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M2" display="inline" overflow="scroll" dspmath="mathml"><mrow><mn mathvariant="normal">1</mn><msup><mi/><mo>∘</mo></msup><mo>×</mo><mn mathvariant="normal">1</mn><msup><mi/><mo>∘</mo></msup></mrow></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="34pt" height="11pt" class="svg-formula" dspmath="mathimg" md5hash="21fbad4d1955efadb851b48211f1f95d"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="bg-21-869-2024-ie00001.svg" width="34pt" height="11pt" src="bg-21-869-2024-ie00001.png"/></svg:svg></span></span> to the continent of North America. We also evaluate how well consistency informs accuracy in overall NEE estimates by filtering models based on their agreement with the variability, magnitude, and seasonality in observed atmospheric CO<span class="inline-formula"><sub>2</sub></span> drawdowns or enhancements. We find that TBMs produce more consistent estimates of NEE for most regions and at most scales relative to inversions. Filtering models using atmospheric CO<span class="inline-formula"><sub>2</sub></span> metrics causes ensemble spread to decrease substantially for TBMs, but not for inversions. This suggests that ensemble spread is likely not a reliable measure of the uncertainty associated with the North American carbon balance at any spatial scale. Promisingly, applying atmospheric CO<span class="inline-formula"><sub>2</sub></span> metrics leads to a set of models with converging flux estimates across TBMs and inversions. Overall, we show that multiscale assessment of the agreement between bottom-up and top-down NEE estimates, aided by regional-scale observational constraints is a promising path towards identifying fine-scale sources of uncertainty and improving both ensemble consistency and accuracy. These findings help refine our understanding of biospheric carbon balance, particularly at scales relevant for informing regional carbon-climate feedbacks.</p>https://bg.copernicus.org/articles/21/869/2024/bg-21-869-2024.pdf |
| spellingShingle | K. T. Foster K. T. Foster W. Sun Y. P. Shiga J. Mao A. M. Michalak A. M. Michalak Multiscale assessment of North American terrestrial carbon balance Biogeosciences |
| title | Multiscale assessment of North American terrestrial carbon balance |
| title_full | Multiscale assessment of North American terrestrial carbon balance |
| title_fullStr | Multiscale assessment of North American terrestrial carbon balance |
| title_full_unstemmed | Multiscale assessment of North American terrestrial carbon balance |
| title_short | Multiscale assessment of North American terrestrial carbon balance |
| title_sort | multiscale assessment of north american terrestrial carbon balance |
| url | https://bg.copernicus.org/articles/21/869/2024/bg-21-869-2024.pdf |
| work_keys_str_mv | AT ktfoster multiscaleassessmentofnorthamericanterrestrialcarbonbalance AT ktfoster multiscaleassessmentofnorthamericanterrestrialcarbonbalance AT wsun multiscaleassessmentofnorthamericanterrestrialcarbonbalance AT ypshiga multiscaleassessmentofnorthamericanterrestrialcarbonbalance AT jmao multiscaleassessmentofnorthamericanterrestrialcarbonbalance AT ammichalak multiscaleassessmentofnorthamericanterrestrialcarbonbalance AT ammichalak multiscaleassessmentofnorthamericanterrestrialcarbonbalance |