Articles | Volume 15, issue 2
https://doi.org/10.5194/gmd-15-649-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/gmd-15-649-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Development and technical paper
| 
26 Jan 2022
Development and technical paper |
| 26 Jan 2022
| 26 Jan 2022
A new exponentially decaying error correlation model for assimilating OCO-2 column-average CO2 data using a length scale computed from airborne lidar measurements
David F. Baker
CORRESPONDING AUTHOR
Cooperative Institute for Research in the Atmosphere, Colorado State University, Fort Collins, CO, USA
Emily Bell
Cooperative Institute for Research in the Atmosphere, Colorado State University, Fort Collins, CO, USA
Kenneth J. Davis
Department of Meteorology and Atmospheric Science, Pennsylvania State University, University Park, PA, USA
Earth and Environmental Systems Institute, Pennsylvania State University, University Park, PA, USA
Joel F. Campbell
NASA Langley Research Center, Hampton, VA, USA
Bing Lin
NASA Langley Research Center, Hampton, VA, USA
Jeremy Dobler
Spectral Sensor Solutions LLC, Fort Wayne, IN, USA
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The tangent linear and adjoint models have been successfully implemented in the MPAS-CO2 system, which has undergone rigorous accuracy testing. This development lays the groundwork for a global carbon flux data assimilation system, which offers the flexibility of high-resolution focus on specific areas, while maintaining a coarser resolution elsewhere. This approach significantly reduces computational costs and is thus perfectly suited for future CO2 geostationery and imager satellites.
Brendan Byrne, David F. Baker, Sourish Basu, Michael Bertolacci, Kevin W. Bowman, Dustin Carroll, Abhishek Chatterjee, Frédéric Chevallier, Philippe Ciais, Noel Cressie, David Crisp, Sean Crowell, Feng Deng, Zhu Deng, Nicholas M. Deutscher, Manvendra K. Dubey, Sha Feng, Omaira E. García, David W. T. Griffith, Benedikt Herkommer, Lei Hu, Andrew R. Jacobson, Rajesh Janardanan, Sujong Jeong, Matthew S. Johnson, Dylan B. A. Jones, Rigel Kivi, Junjie Liu, Zhiqiang Liu, Shamil Maksyutov, John B. Miller, Scot M. Miller, Isamu Morino, Justus Notholt, Tomohiro Oda, Christopher W. O'Dell, Young-Suk Oh, Hirofumi Ohyama, Prabir K. Patra, Hélène Peiro, Christof Petri, Sajeev Philip, David F. Pollard, Benjamin Poulter, Marine Remaud, Andrew Schuh, Mahesh K. Sha, Kei Shiomi, Kimberly Strong, Colm Sweeney, Yao Té, Hanqin Tian, Voltaire A. Velazco, Mihalis Vrekoussis, Thorsten Warneke, John R. Worden, Debra Wunch, Yuanzhi Yao, Jeongmin Yun, Andrew Zammit-Mangion, and Ning Zeng
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Changes in the carbon stocks of terrestrial ecosystems result in emissions and removals of CO2. These can be driven by anthropogenic activities (e.g., deforestation), natural processes (e.g., fires) or in response to rising CO2 (e.g., CO2 fertilization). This paper describes a dataset of CO2 emissions and removals derived from atmospheric CO2 observations. This pilot dataset informs current capabilities and future developments towards top-down monitoring and verification systems.
Hélène Peiro, Sean Crowell, Andrew Schuh, David F. Baker, Chris O'Dell, Andrew R. Jacobson, Frédéric Chevallier, Junjie Liu, Annmarie Eldering, David Crisp, Feng Deng, Brad Weir, Sourish Basu, Matthew S. Johnson, Sajeev Philip, and Ian Baker
Atmos. Chem. Phys., 22, 1097–1130, https://doi.org/10.5194/acp-22-1097-2022, https://doi.org/10.5194/acp-22-1097-2022, 2022
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Satellite CO2 observations are constantly improved. We study an ensemble of different atmospheric models (inversions) from 2015 to 2018 using separate ground-based data or two versions of the OCO-2 satellite. Our study aims to determine if different satellite data corrections can yield different estimates of carbon cycle flux. A difference in the carbon budget between the two versions is found over tropical Africa, which seems to show the impact of corrections applied in satellite data.
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Joel F. Campbell, Bing Lin, and Zhaoyan Liu
Atmos. Meas. Tech., 18, 4003–4004, https://doi.org/10.5194/amt-18-4003-2025, https://doi.org/10.5194/amt-18-4003-2025, 2025
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This is a reply to a recent article by Christoph Kiemle et al., critical of CO2 measurements using continuous-wave (CW) lidar. We show CW lidar is not only capable of measuring range but also capable of measuring range to the required accuracy without the aid of an external altimeter.
Jason P. Horne, Scott J. Richardson, Samantha L. Murphy, Helen C. Kenion, Bernd J. Haupt, Benjamin J. Ahlswede, Natasha L. Miles, and Kenneth J. Davis
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2025-232, https://doi.org/10.5194/essd-2025-232, 2025
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Bryan Edward Fabbri, Gregory L. Schuster, Frederick M. Denn, Bing Lin, David A. Rutan, Wenying Su, Zachary A. Eitzen, James J. Madigan Jr., Robert Arduini, and Norman G. Loeb
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A new upwelling longwave (LW) measuring technique is presented without the influence of an obstruction on a pyrgeometer using an infrared radiation thermometer, a downwelling LW pyrgeometer and an air temperature probe. This new technique could be used at other locations with obstruction issues and also to verify existing upwelling longwave pyrgeometer measurements. Satellite projects such as the Clouds and the Earth's Radiant Energy System rely on accurate measurements to verify their models.
Tobias Gerken, Kenneth J. Davis, Klaus Keller, and Sha Feng
EGUsphere, https://doi.org/10.5194/egusphere-2025-341, https://doi.org/10.5194/egusphere-2025-341, 2025
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We apply the Patient Rule Induction Method (PRIM) technique to airborne CO2 and meteorological data to better understand atmospheric conditions and implications for carbon dioxide model-observation-mismatches. We found PRIM is capable of separating observations from different seasons and levels based on atmospheric conditions. Large magnitude carbon dioxide model-observation-differences were associated with non-typical atmospheric conditions, with implications for transport model evaluation.
Zhaoyan Liu, Bing Lin, Joel F. Campbell, Jirong Yu, Jihong Geng, and Shibin Jiang
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Tao Zheng, Sha Feng, Jeffrey Steward, Xiaoxu Tian, David Baker, and Martin Baxter
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We assess the ability of the GreenLITE™ emissions monitoring system to detect, localize, and quantify methane emissions and evaluate its performance using a DOE-supported Continuous Monitoring Protocol. GreenLITE™ detected emission rates as low as 0.22 kg/h with a 90 % detection limit of 0.89 kg/h and wind-normalized detection limit of 0.44 (kg/h)/(m/s).
Daniel J. Varon, Daniel J. Jacob, Benjamin Hmiel, Ritesh Gautam, David R. Lyon, Mark Omara, Melissa Sulprizio, Lu Shen, Drew Pendergrass, Hannah Nesser, Zhen Qu, Zachary R. Barkley, Natasha L. Miles, Scott J. Richardson, Kenneth J. Davis, Sudhanshu Pandey, Xiao Lu, Alba Lorente, Tobias Borsdorff, Joannes D. Maasakkers, and Ilse Aben
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We use TROPOMI satellite observations to quantify weekly methane emissions from the US Permian oil and gas basin from May 2018 to October 2020. We find that Permian emissions are highly variable, with diverse economic and activity drivers. The most important drivers during our study period were new well development and natural gas price. Permian methane intensity averaged 4.6 % and decreased by 1 % per year.
Zachary Barkley, Kenneth Davis, Natasha Miles, Scott Richardson, Aijun Deng, Benjamin Hmiel, David Lyon, and Thomas Lauvaux
Atmos. Chem. Phys., 23, 6127–6144, https://doi.org/10.5194/acp-23-6127-2023, https://doi.org/10.5194/acp-23-6127-2023, 2023
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Using methane monitoring instruments attached to towers, we measure methane concentrations and quantify methane emissions coming from the Marcellus and Permian oil and gas basins. In the Marcellus, emissions were 3 times higher than the state inventory across the entire monitoring period. In the Permian, we see a sharp decline in emissions aligning with the onset of the COVID-19 pandemic. Tower observational networks can be utilized in other basins for long-term monitoring of emissions.
Brendan Byrne, David F. Baker, Sourish Basu, Michael Bertolacci, Kevin W. Bowman, Dustin Carroll, Abhishek Chatterjee, Frédéric Chevallier, Philippe Ciais, Noel Cressie, David Crisp, Sean Crowell, Feng Deng, Zhu Deng, Nicholas M. Deutscher, Manvendra K. Dubey, Sha Feng, Omaira E. García, David W. T. Griffith, Benedikt Herkommer, Lei Hu, Andrew R. Jacobson, Rajesh Janardanan, Sujong Jeong, Matthew S. Johnson, Dylan B. A. Jones, Rigel Kivi, Junjie Liu, Zhiqiang Liu, Shamil Maksyutov, John B. Miller, Scot M. Miller, Isamu Morino, Justus Notholt, Tomohiro Oda, Christopher W. O'Dell, Young-Suk Oh, Hirofumi Ohyama, Prabir K. Patra, Hélène Peiro, Christof Petri, Sajeev Philip, David F. Pollard, Benjamin Poulter, Marine Remaud, Andrew Schuh, Mahesh K. Sha, Kei Shiomi, Kimberly Strong, Colm Sweeney, Yao Té, Hanqin Tian, Voltaire A. Velazco, Mihalis Vrekoussis, Thorsten Warneke, John R. Worden, Debra Wunch, Yuanzhi Yao, Jeongmin Yun, Andrew Zammit-Mangion, and Ning Zeng
Earth Syst. Sci. Data, 15, 963–1004, https://doi.org/10.5194/essd-15-963-2023, https://doi.org/10.5194/essd-15-963-2023, 2023
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Changes in the carbon stocks of terrestrial ecosystems result in emissions and removals of CO2. These can be driven by anthropogenic activities (e.g., deforestation), natural processes (e.g., fires) or in response to rising CO2 (e.g., CO2 fertilization). This paper describes a dataset of CO2 emissions and removals derived from atmospheric CO2 observations. This pilot dataset informs current capabilities and future developments towards top-down monitoring and verification systems.
Rory A. Barton-Grimley, Amin R. Nehrir, Susan A. Kooi, James E. Collins, David B. Harper, Anthony Notari, Joseph Lee, Joshua P. DiGangi, Yonghoon Choi, and Kenneth J. Davis
Atmos. Meas. Tech., 15, 4623–4650, https://doi.org/10.5194/amt-15-4623-2022, https://doi.org/10.5194/amt-15-4623-2022, 2022
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HALO is a multi-functional lidar that measures CH4 columns and profiles of H2O mixing ratio and aerosol/cloud optical properties. HALO supports carbon cycle, weather dynamics, and radiation science suborbital research and is a technology testbed for future space-based differential absorption lidar missions. In 2019 HALO collected CH4 columns and aerosol/cloud profiles during the ACT-America campaign. Here we assess HALO's CH4 accuracy and precision compared to co-located in situ observations.
Vanessa C. Monteiro, Natasha L. Miles, Scott J. Richardson, Zachary Barkley, Bernd J. Haupt, David Lyon, Benjamin Hmiel, and Kenneth J. Davis
Earth Syst. Sci. Data, 14, 2401–2417, https://doi.org/10.5194/essd-14-2401-2022, https://doi.org/10.5194/essd-14-2401-2022, 2022
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We describe a network of five ground-based in situ towers, equipped to measure concentrations of methane, carbon dioxide, hydrogen sulfide, and the isotopic ratio of methane, in the Permian Basin, United States. The main goal is to use methane concentrations with atmospheric models to determine methane emissions from one of the Permian sub-basins. These datasets can improve emissions estimations, leading to best practices in the oil and natural gas industry, and policies for emissions reduction.
Hélène Peiro, Sean Crowell, Andrew Schuh, David F. Baker, Chris O'Dell, Andrew R. Jacobson, Frédéric Chevallier, Junjie Liu, Annmarie Eldering, David Crisp, Feng Deng, Brad Weir, Sourish Basu, Matthew S. Johnson, Sajeev Philip, and Ian Baker
Atmos. Chem. Phys., 22, 1097–1130, https://doi.org/10.5194/acp-22-1097-2022, https://doi.org/10.5194/acp-22-1097-2022, 2022
Short summary
Short summary
Satellite CO2 observations are constantly improved. We study an ensemble of different atmospheric models (inversions) from 2015 to 2018 using separate ground-based data or two versions of the OCO-2 satellite. Our study aims to determine if different satellite data corrections can yield different estimates of carbon cycle flux. A difference in the carbon budget between the two versions is found over tropical Africa, which seems to show the impact of corrections applied in satellite data.
Timothy G. Pernini, T. Scott Zaccheo, Jeremy Dobler, and Nathan Blume
Atmos. Meas. Tech., 15, 225–240, https://doi.org/10.5194/amt-15-225-2022, https://doi.org/10.5194/amt-15-225-2022, 2022
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We demonstrate a novel approach to estimating emissions from oil sands operations that utilizes the GreenLITE™ gas concentration measurement system and an atmospheric model. While deployed at a facility in the Athabasca region of Alberta, Canada, CH4 emissions from a tailings pond were estimated to be 7.2 t/d for July–October 2019, and 5.1 t/d for March–July 2020. CH4 emissions from an open-pit mine were estimated to be 24.6 t/d for September–October 2019.
Tao Zheng, Sha Feng, Kenneth J. Davis, Sandip Pal, and Josep-Anton Morguí
Geosci. Model Dev., 14, 3037–3066, https://doi.org/10.5194/gmd-14-3037-2021, https://doi.org/10.5194/gmd-14-3037-2021, 2021
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Carbon dioxide is the most important greenhouse gas. We develop the numerical model that represents carbon dioxide transport in the atmosphere. This model development is based on the MPAS model, which has a variable-resolution capability. The purpose of developing carbon dioxide transport in MPAS is to allow for high-resolution transport model simulation that is not limited by the lateral boundaries. It will also form the base for a future development of MPAS-based carbon inversion system.
David R. Lyon, Benjamin Hmiel, Ritesh Gautam, Mark Omara, Katherine A. Roberts, Zachary R. Barkley, Kenneth J. Davis, Natasha L. Miles, Vanessa C. Monteiro, Scott J. Richardson, Stephen Conley, Mackenzie L. Smith, Daniel J. Jacob, Lu Shen, Daniel J. Varon, Aijun Deng, Xander Rudelis, Nikhil Sharma, Kyle T. Story, Adam R. Brandt, Mary Kang, Eric A. Kort, Anthony J. Marchese, and Steven P. Hamburg
Atmos. Chem. Phys., 21, 6605–6626, https://doi.org/10.5194/acp-21-6605-2021, https://doi.org/10.5194/acp-21-6605-2021, 2021
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The Permian Basin (USA) is the world’s largest oil field. We use tower- and aircraft-based approaches to measure how methane emissions in the Permian Basin changed throughout 2020. In early 2020, 3.3 % of the region’s gas was emitted; then in spring 2020, the loss rate temporarily dropped to 1.9 % as oil price crashed. We find this short-term reduction to be a result of reduced well development, less gas flaring, and fewer abnormal events despite minimal reductions in oil and gas production.
Steven T. Massie, Heather Cronk, Aronne Merrelli, Christopher O'Dell, K. Sebastian Schmidt, Hong Chen, and David Baker
Atmos. Meas. Tech., 14, 1475–1499, https://doi.org/10.5194/amt-14-1475-2021, https://doi.org/10.5194/amt-14-1475-2021, 2021
Short summary
Short summary
The OCO-2 science team is working to retrieve CO2 measurements that can be used by the carbon cycle community to calculate regional sources and sinks of CO2. The retrieved data, however, are in need of improvements in accuracy. This paper discusses several ways in which 3D cloud metrics (such as the distance of a measurement to the nearest cloud) can be used to account for cloud effects in the OCO-2 CO2 data files.
Xueying Yu, Dylan B. Millet, Kelley C. Wells, Daven K. Henze, Hansen Cao, Timothy J. Griffis, Eric A. Kort, Genevieve Plant, Malte J. Deventer, Randall K. Kolka, D. Tyler Roman, Kenneth J. Davis, Ankur R. Desai, Bianca C. Baier, Kathryn McKain, Alan C. Czarnetzki, and A. Anthony Bloom
Atmos. Chem. Phys., 21, 951–971, https://doi.org/10.5194/acp-21-951-2021, https://doi.org/10.5194/acp-21-951-2021, 2021
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Methane concentrations have doubled since 1750. The US Upper Midwest is a key region contributing to such trends, but sources are poorly understood. We collected and analyzed aircraft data to resolve spatial and timing biases in wetland and livestock emission estimates and uncover errors in inventory treatment of manure management. We highlight the importance of intensive agriculture for the regional and US methane budgets and the potential for methane mitigation through improved management.
Petter Weibring, Dirk Richter, James G. Walega, Alan Fried, Joshua DiGangi, Hannah Halliday, Yonghoon Choi, Bianca Baier, Colm Sweeney, Ben Miller, Kenneth J. Davis, Zachary Barkley, and Michael D. Obland
Atmos. Meas. Tech., 13, 6095–6112, https://doi.org/10.5194/amt-13-6095-2020, https://doi.org/10.5194/amt-13-6095-2020, 2020
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The present study describes an autonomously operated instrument for high-precision (20–40 parts per trillion in 1 s) measurements of ethane during actual airborne operations on a small aircraft platform (NASA's King Air B200). This paper discusses the dynamic nature of airborne performance due to various aircraft-induced perturbations, methods devised to identify such events, and solutions we have enacted to circumvent these perturbations.
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Short summary
The OCO-2 satellite measures many closely spaced column-averaged CO2 values around its orbit. To give these data proper weight in flux inversions, their error correlations must be accounted for. Here we lay out a 1-D error model with correlations that die out exponentially along-track to do so. A correlation length scale of ∼20 km is derived from column CO2 measurements from an airborne lidar flown underneath OCO-2 for use in this model. The model's performance is compared to previous ones.
The OCO-2 satellite measures many closely spaced column-averaged CO2 values around its orbit....
