Skip to content

Carbon Team

CIRA Carbon Team in 2021.  Back row from left:  Greg Mcgarragh, Peter Somkuti, Andrew Schuh, David Baker.  Front row: Niki Jacobs, Emily Bell, Heather Cronk, Sean Crowell (guest), Chris O’Dell.  Not pictured: Tommy Taylor, Ian Baker.

The research in my group is driven primarily by a desire to increase our knowledge of anthropogenically-forced global climate change. In order to be able to accurately predict future climate for a given scenario of human emissions, it is important to understand currently-occurring changes in the earth system. In my group this is done primarily through global-scale satellite measurements of climatically important variables, such as longwave radiation, clouds, and greenhouse gases (GHGs) such as carbon dioxide. One of our main projects is to better understand the earth’s carbon cycle through precision measurements of carbon dioxide and methane, the two most important greenhouse gases. Precision measurements of these gases may one day lead to the ability to do “top-down” accounting of GHG emissions, which could help in verifying such emissions in a treaty-relevant manner.

Carbon Group Working Areas:

  • Satellite-based greenhouse gas observations (primarily carbon dioxide and methane)
  • Carbon flux inverse modeling
  • Biospheric/land surface modeling of carbon, water and energy exchange
  • Atmospheric transport of trace gases

Key Science Goals:

  • A better understanding of the present state of the earth’s carbon cycle, and the contribution of the biosphere to carbon cycling at urban to regional to global scales.
  • Observing, understanding, and attributing changes to the earth’s carbon cycle in the era of climate change
  • Feasibility of monitoring anthropogenic emissions of greenhouse gases from satellites



Masters or PhD Student Needed

Fully-funded MSc. or Ph.D. research position at Colorado State University for satellite-based measurements of greenhouse gases, starting August 2024.


The Cooperative Institute for Research in the Atmosphere at Colorado State University seeks talented and motivated individuals to join our team measuring and monitoring atmospheric greenhouse gases (GHGs) using state-of-the-art satellite sensors.  Our group is one of the premier teams in the world that makes these measurements possible.  This began with groundbreaking work on how to “retrieve” carbon dioxide from the first dedicated GHG satellites,  JAXA’s Greenhouse Gases Observing Satellite (GOSAT) and NASA’s Orbiting Carbon Observatory-2 (OCO-2).  We also support measurements from OCO-3, installed on the International Space Station since 2019.  We are now expanding our research to new, more powerful sensors such as MethaneSat, launching in mid-2024.  Our measurements are used to both monitor anthropogenic GHG emissions to inform the United Nation’s 5-year Global Stocktake in support of the Paris climate Agreement, as well as to monitor changes to natural sources and sinks of carbon in the Earth’s biosphere that are currently being wrought by global climate change.  Our group collaborates strongly with multiple NASA centers (e.g., NASA’s Jet Propulsion Laboratory and NASA’s Goddard Spaceflight Center).


The successful applicant will learn the basics of atmospheric radiative transfer, scattering by clouds and aerosols, and computer coding necessary to both improve our ability to make these measurements and to utilize these measurements for novel science. She or he should have an undergraduate degree or equivalent in physics, math, atmospheric science, or other hard science discipline, as well as a reasonable facility with at least one programming language (e.g. Python, Matlab, R, IDL, Fortran, C++, Java). Applicants must also have completed a calculus-based math course sequence including differential equations and vector analysis as well as a calculus-based physics course sequence including kinetics, electricity and magnetism, and some modern topics.


Interested parties should email Dr. for more information.  Applications to the Colorado State University Department of Atmospheric Science are due  by January 1st, 2024 in order to start in the Fall 2024 semester.   Colorado State University (CSU) is located at the edge of the beautiful Rocky Mountains in Fort Collins, Colorado.  Fort Collins has a high quality of life and is often ranked as one of the best places to live in America.  CSU Atmospheric Science is a leading global institution, and as such, all members of our community regardless of race, ethnicity, culture, religion, sexual orientation, gender identity and expression, physical ability, age, socioeconomic status or nationality are welcome as equal contributors. We value and appreciate diversity, and we believe that diversity on our campus strengthens our entire scientific community.

Supporting OCO-2 and OCO-3 measurements of carbon dioxide, future measurements of carbon dioxide from the soon-to-launch MethaneSAT, and measurements of carbon dioxide, methane, and carbon monoxide from potential future instruments, such as the proposed geostationary GHG instrument GeoCarb


Image Credit: JPL


Carbon Group Working Areas:

  • Satellite-based greenhouse gas observations (primarily carbon dioxide and methane)
  • Carbon flux inverse modeling
  • Biospheric/land surface modeling of carbon, water and energy exchange
  • Atmospheric transport of trace gases

Key Science Goals:

  • A better understanding of the present state of the earth’s carbon cycle, and the contribution of the biosphere to carbon cycling at urban to regional to global scales.
  • Observing, understanding, and attributing changes to the earth’s carbon cycle in the era of climate change
  • Feasibility of monitoring anthropogenic emissions of greenhouse gases from satellites


Active Projects

Orbiting Carbon Observatory 2 and 3 :: algorithm development and data analysis (with NASA JPL)

GeoCarb :: continuing development/calibration of the instrument towards re-funding & space-flight (with Lockheed-Martin and LumenUs)

MethaneSat :: developing operational CO2 retrievals (with Environmental Defense Fund and Harvard Univ.)

Evaluating carbon dynamics across regions and scales (NASA, NOAA, NSF)

Designing optimized space-based GHG observing systems (with NASA Goddard)

Utilization of solar induced fluorescence (SIF) towards characterizing dryland agriculture (NASA and USDA)

Using a Novel Multiscale Modeling Framework to Characterize Brazil’s Carbon Cycle (NASA Carbon Monitoring System)

Constraining carbon fluxes and transport patterns using new spatiotemporal information in remotely sensed CO2

GHG Center Funded Trace Gas Flux Inversion Workshops

Past Projects

ACT-America field campaign (with NASA and Penn State)

Japanese Greenhouse Gases Observing Satellite (GOSAT) :: instrument calibration, retrieval algorithm development and data analysis.

Our Working Themes:

  • Climate and Weather Processes
  • Satellite Algorithm Development, Training and Education
  • Modeling Systems Research
  • Data Assimilation


Maity, S., Patra, P.K., …, Baker, D., et al., New metric for semi-hemispheric CO2 flux evaluation using meridional CO2 gradients, in prep

Cui, Y.Y., …, Baker, D., Schuh, A.E., et al., Regional evaluation of global inverse estimates of CO2 net ecosystem exchange in multiple ecoregions of the United States using the ACT-America aircraft campaigns, in prep

Mendonca, J., … O’Dell, C.W., et. al., A neural network approach to filtering OCO-2 retrievals over snow, in prep

Published 2024

Bertolacci, M., Zammit-Mangion, A., Schuh, A.E., et al., Inferring changes to the global carbon cycle with WOMBAT v2.0, a hierarchical flux-inversion framework, Ann. Appl. Stat., 2024,

Published 2023

Jacobs, N., O’Dell, C.W., Taylor, T.E., et. al., The importance of digital elevation model accuracy in XCO2 retrievals: improving the OCO-2 ACOS v11 product, Atmos. Meas. Tech., 2023.

McGarragh, G., O’Dell, C.W., et. al., The GeoCarb greenhouse gas retrieval algorithm: Simulations and sensitivity to sources of uncertainty, Atmos. Meas. Tech., 2023.

Gaubert, B., … Baker, D.F. , … Jacobs, N.O’Dell, C.W.Taylor, T.E., et al., Neutral tropical African CO2 exchange estimated from aircraft and satellite observations, Global Biogeochemical Cycles, 37 (12), 2023,

Schuh, A. E. and Jacobson, A. R., Uncertainty in parameterized convection remains a key obstacle for estimating surface fluxes of carbon dioxide, Atmos. Chem. Phys., 23 (11), 2023,

Keely, W., …, O’Dell, C.W., A nonlinear data-driven approach to bias correction of XCO2 for NASA’s OCO-2 ACOS version 10, Atmos. Meas. Tech., 16 (23), 2023,

Byrne, B., Baker, D.F., …, O’Dell, C.W., …, Schuh, A.E., et al., National CO2 budgets (2015–2020) inferred from atmospheric CO2 observations in support of the Global Stocktake, Earth Syst. Sci. Data, 2023,

Hakkarainen, J., …, O’Dell, C.W., et al., Building a bridge: Characterizing major anthropogenic point sources in the South
African Highveld region using OCO-3 carbon dioxide Snapshot Area Maps and Sentinel-5P/TROPOMI nitrogen dioxide columns, Environmental Research Letters, 18, 2023,

Taylor, T.E., O’Dell, C.W., et. al., Evaluating the consistency between OCO-2 and OCO-3 XCO2 estimates derived from the NASA ACOS version 10 retrieval algorithm, Atmos. Meas. Tech., 2023,

Bell, E., O’Dell, C. W., Taylor, T. E., et al., Exploring bias in the OCO-3 snapshot area mapping mode via geometry, surface, and aerosol effects, Atmos. Meas. Tech., 16, 109–133, 2023,

Published 2022

Baker, D.F., Bell, E., et al., A new exponentially decaying error correlation model for assimilating OCO-2 column-average CO2 data using a length scale computed from airborne lidar measurements Geosci. Model Dev., 15 (2), 2022,

Cui, Y.Y., …, Baker, D.F.,…,Schuh, A.E., et al., Evaluating global atmospheric inversions of terrestrial net ecosystem exchange CO2 over North America on seasonal and sub-continental scales, Geophysical Res. Letters, 49, 2022,

Gourdji, S.M., …, Baker, I.T., et al., A modified vegetation photosynthesis and respiration model (VPRM) for the Eastern USA and Canada, evaluated with comparison to atmospheric observations and other biospheric models, J. Geophys. Res. – Biogeosci., 2022,

Keller, G.R., …, O’Dell, C.W., et al., Inflight radiometric calibration and performance of the orbiting carbon observatory 3 for version 10 products. IEEE Transactions on Geoscience and Remote Sensing, 60, 2022,

Kuai, L., …, Baker, I.T., et al., Quantifying northern high latitude gross primary productivity (GPP) using carbonyl sulfide (OCS), Glob. Biogeochem. Cy., 2022,

Nassar, R., …, O’Dell, C.W., et al., Tracking CO2 emission reductions from space: A case study at Europe’s largest fossil fuel power plant, Frontiers in Remote Sensing, 3, 2022,

Peiro, H., Crowell, S., Schuh, A.E., Baker, D.F., O’Dell, C.W., Baker, I.T., Four years of global carbon cycle observed from the Orbiting Carbon Observatory 2 (OCO-2) version 9 and in situ data and comparison to OCO-2 version 7, Atmos. Chem. Phys., 2022,

Philip, S., Johnson, M.S., Baker, D.F., et al., OCO-2 satellite-imposed constraints on terrestrial biospheric CO2 fluxes over South Asia, J. Geophys. Res.- Atmospheres, 2022,

Schuh, A.E., et al. On the role of atmospheric model transport uncertainty in estimating the Chinese land carbon sink. Nature, 603, E13–E14, 2022,

Stinecipher, J.R., …, Baker, I.T., Remotely sensed carbonyl sulfide constrains model estimates of Amazon primary productivity, Geophys. Res. Let., 2022,

Taylor, T.E., O’Dell, C.W., et. al., An 11-year record of XCO2 estimates derived from GOSAT measurements using the NASA ACOS version 9 retrieval algorithm. Earth System Science Data, 14 (1), 325-360, 2022,

Walley, S., …, Bell, E., … Baker, D.F., …, O’Dell, C.W., et al., Airborne lidar measurements of XCO2 in synoptically active environment and associated comparisons with numerical simulations, Journal of Geophysical Research: Atmospheres, 127 (16), 2022,

Wang, Y.,…, Baker, D.F., Schuh, A.E., et al., Constraining China’s land carbon sink from emerging satellite CO2 observations: progress and challenges, Global Change Biology, 2022,

Zhang, L., Davis, K. J., Schuh, A. E., et al. Multi-season evaluation of CO2 weather in OCO-2 MIP models. Journal of Geophysical Research: Atmospheres, 127, 2022,

Published 2021

Buchwitz, M., …, O’Dell, C. W., et al., Can a regional-scale reduction of atmospheric CO2 during the COVID-19 pandemic be detected from space? A case study for East China using satellite XCO2 retrievals, Atmos. Meas. Tech., 14 (3), 2021,

Cui, Y.Y., Baker, D.F., et al., Evaluation of CarbonTracker’s inverse estimates of North American net ecosystem exchange of CO2 from different observing systems using ACT-America airborne observations, J. Geophys. Res.- Atm., 2021,

Davis, K.J., …,Baker, D.F., Baker, I.T.,…, O’Dell, C.W., Schuh, A.E., et al., The Atmospheric Carbon and Transport (ACT) America Mission., Bull. Amer. Meteorol. Soc., 2021,

Feng, S., …, Baker, I.T., et al., Joint CO2 mole fraction and flux analysis confirms missing processes in CASA
terrestrial carbon uptake over North America, Glob. Biogeochem. Cy., 2021,

Gallup, S.M., Baker, I.T., et al., Accurate simulation of both sensitivity and variability for Amazonian photosynthesis: Is it too much to ask?, J. Adv. Mod. Earth Sy., 2021,

Gaudet, B.J.,…, Schuh, A.E., et al., Regional-scale, sector-specific evaluation of global CO2 inversion models using aircraft data from the ACT-America project, JGR-Atmospheres, 2020,

Hu, L., …, Baker, I.T., COS-derived GPP relationships with temperature and light help explain high-latitude atmospheric CO2 seasonal cycle amplification, Proc. Nat. Acad. Sci., 2021, doi:

Kooijmans, L.M.J, …, Baker, I.T., et al., Evaluation of carbonyl sulfide biosphere exchange in the Simple Biosphere Model (SiB4), Biogeosciences, 2021,

Lei, R., …, O’Dell, C.W., et al., Fossil fuel CO2 emissions over metropolitan areas from space: A multi-model analysis of OCO-2 data over Lahore, Pakistan, Rem. Sens. Env., 264, 2021,

Massie, S.T., …, O’Dell, C.W., … Baker, D.F., Analysis of 3D cloud effects in OCO-2 XCO2 retrievals, Atmos. Meas. Tech., 14 (2), 2021,

Mendonca J., Nassar R., O’Dell C.W., et al., Assessing the feasibility of using a neural network to filter Orbiting Carbon Observatory 2 (OCO-2) retrievals at northern high latitudes, Atmos. Meas. Tech., 14 (12), 2021,

Nassar, R., …, O’Dell, C.W., et al., Advances in quantifying power plant CO2 emissions with OCO-2, Rem. Sens. Env., 264, 2021,

Parazoo, N., …, Baker, I.T., et al., Covariation of airborne biogenic tracers (CO2, COS and CO) support stronger than expected growing season photosynthetic uptake in the southeastern US, Glob. Biogeochem. Cy., 2021,

Schuh, A.E. et al., Far-field biogenic and anthropogenic emissions as a dominant source of variability in local urban carbon budgets: A global high-resolution model study with implications for satellite remote sensing, Remote Sensing of Environment, Volume 262,2021,

Somkuti, P., O’Dell, C.W., …, McGarragh, G.R., et al., Solar-induced chlorophyll fluorescence from the Geostationary Carbon Cycle Observatory (GeoCarb): An extensive simulation study, Rem. Sens. Env., 263, 2021,

Weir, B., Crisp, D., O’Dell, C.W., et al., Regional impacts of COVID-19 on carbon dioxide detected worldwide from space, Science Advances, 7 (45), 2021,

Published 2020

Wang, J., …, O’Dell, C.W., et al., Large Chinese land carbon sink estimated from atmospheric carbon dioxide data, Nature, 586 (7831), 2020,

Payne, V.H., …, O’Dell, C.W., Absorption coefficient (ABSCO) tables for the Orbiting Carbon Observatories: Version 5.1, Journal of Quantitative Spectroscopy and Radiative Transfer, 255, 2020,

Bell, E., O’Dell, C.W., et al., Evaluation of OCO‐2 XCO2 variability at local and synoptic scales using lidar and in situ observations from the ACT‐America campaigns, Journal of Geophysical Research: Atmospheres, 125 (10), 2020,

Campbell, J.F., …, O’Dell, C.W., et al., Field evaluation of column CO2 retrievals from intensity‐modulated continuous‐wave differential absorption lidar measurements during the ACT‐America campaign, Earth and Space Science, 7 (12),

Johnson, M.S., …, O’Dell, C.W., Carbon dioxide emissions during the 2018 Kilauea volcano eruption estimated using OCO‐2 satellite retrievals, Geophysical Research Letters, 47 (24), 2020,

Chevallier, F., …, O’Dell, C.W., Local anomalies in the column‐averaged dry air mole fractions of carbon dioxide across the globe during the first months of the coronavirus recession, Geophysical Research Letters, 47 (22), 2020,

Taylor, T.E., et. al., OCO-3 early mission operations and initial (vEarly) XCO2 and SIF retrievals, Remote Sensing of Environment, 251, 2020.

Feng, S.,…, Schuh, A.E., Baker, I.T., Seasonal characteristics of model uncertainties from biogenic fluxes, transport, and large‐scale boundary inflow in atmospheric CO2 simulations over North America, JGR-Atmospheres, 2020,

Yu, S., …, Taylor, T.E., O’Dell, C.W., et al., Stability assessment of OCO-2 radiometric calibration using aqua MODIS as a reference, Remote Sensing, 12 (8), 2020,

Nelson, R. R., …, O’Dell, C.W., Retrieved wind speed from the Orbiting Carbon Observatory-2, Atmos. Meas. Tech., 13 (12), 2020,

Jacobs, N., …, O’Dell, C. W., Quality controls, bias, and seasonality of CO2 columns in the boreal forest with Orbiting Carbon Observatory-2, Total Carbon Column Observing Network, and EM27/SUN measurements, Atmos. Meas. Tech., 13 (9), 2020,

Reuter, M., …, O’Dell, C. W., et al., Ensemble-based satellite-derived carbon dioxide and methane column-averaged dry-
air mole fraction data sets (2003–2018) for carbon and climate applications, Atmos. Meas. Tech., 13 (2), 2020,

Wang, J., …, Baker, D.F., et al., The impacts of fossil fuel emission uncertainties and accounting for 3-D chemical CO2 production on inverse natural carbon flux estimates from satellite and in situ data, Environ. Res. Lett., 2020,

Published 2019

Reuter, M., …, O’Dell, C.W., et al., Towards monitoring localized CO2 emissions from space: co-located regional CO2 and NO2 enhancements observed by the OCO-2 and S5P satellites, Atmos. Chem. Phys., 19 (14), 2019,

Baker, I.T., et al., Surface-atmosphere coupling scale, the fate of water, and ecophysiological function in a Brazilian forest, Adv. Mod. Earth Sy., 11 (8), 2019,

Haynes, K.D., Baker, I.T., et al., Representing grasslands using dynamic prognostic phenology based on biological growth stages: 1. Implementation in the Simple Biosphere Model (SiB4), J. Adv. Mod. Earth Sy., 11 (12), 2019,

Haynes, K.D., Baker, I.T., et al, Representing grasslands using dynamic prognostic phenology based on biological growth stages: 2. Carbon cycling, J. Adv. Mod. Earth Sy., 11 (12), 2019,

Schuh, A.E.,…, Baker, D.F., et al., Quantifying the impact of atmospheric transport uncertainty on CO2 surface flux estimates, Global Biogeochemical Cycles, 2019,

Crowell, S., Baker, D.F., Schuh, A.E.,…,O’Dell, C.W., et al., The 2015–2016 Carbon Cycle As Seen from OCO-2 and the Global In Situ Network, Atmos. Chem. Phys., 2019,

Eldering, A., Taylor, T.E., O’Dell, C.W. and Pavlick, R., The OCO-3 mission: measurement objectives and expected performance based on 1 year of simulated data, Atmospheric Measurement Techniques, 12 (4), 2341-2370, 2019,

Kulawik, S.S., O’Dell, C.W., Nelson, R. R., and Taylor, T. E., Validation of OCO-2 error analysis using simulated retrievals, Atmos. Meas. Tech., 12 (10), 2019,

Kulawik, S.S., Crowell. S., Baker, D.F., …, O’Dell, C.W., et al., Characterization of OCO-2 and ACOS-GOSAT biases and errors for CO2 flux estimates, Atmos. Meas. Tech. Discuss., 2019,

Chevallier, F., Remaud, M., O’Dell, C.W., Baker, D.F., and Cozic, A., Objective evaluation of surface- and satellite-driven carbon dioxide atmospheric inversions, Atmos. Chem. Phys., 19 (22), 2019,

Kiel, M., O’Dell, C.W., et. al., How bias correction goes wrong: measurement of XCO2 affected by erroneous surface pressure estimates, Atmospheric Measurement Techniques, 12 (4), 2019,

Nelson, R.R., and O’Dell, C.W., The impact of improved aerosol priors on near-infrared measurements of carbon dioxide, Atmospheric Measurement Techniques, 12 (3), 2019,

Byrne, B., …, Baker, D.F., et al., On what scales can GOSAT flux inversions constrain anomalies in terrestrial ecosystems?, Atmos. Chem. Phys., 2019,

Palmer, P.I., Feng, L., Baker, D.F., Chevallier, F., Bosch, H., and Somkuti, P., Net carbon emissions from African biosphere dominate pan-tropical atmospheric CO2 signal, Nature Communications, 2019,

Bushinsky, S.M., …, Baker, D.F., et al., Reassessing Southern Ocean air-sea CO2 flux estimates with the addition of biogeochemical float observations, Glob. Biogeochem. Cycles, 2019,

Philip, S., …, Baker, D.F., et al., Prior biosphere model impact on global terrestrial CO2 fluxes estimated from OCO-2 retrievals, Atmos. Chem. Phys., 2019,

Kawa, S.R., Abshire, J.B., Baker, D.F., et al., Active Sensing of CO2 Emissions over Nights, Days, and Seasons (ASCENDS): Final Report of the ASCENDS Ad Hoc Science Definition Team, 2019,

Published 2018

Basu, S., Baker, D.F., et al., The impact of transport model differences on CO2 surface flux estimates from OCO-2 retrievals of column average CO2, Atmos. Chem. Phys., 2018,

O’Dell, C.W.,…Taylor, T.E.,…,Baker, D.F., et. al., Improved retrievals of carbon dioxide from Orbiting Carbon Observatory-2 with the version 8 ACOS algorithm, Atmospheric Measurements Techniques, 11 (12), 2018,

Buchwitz, M.,…, O’Dell, C.W., Computation and analysis of atmospheric carbon dioxide annual mean growth rates from satellite observations during 2003–2016, Atmos. Chem. Phys., 18 (23), 2019,

Moore, B., …, O’Dell, C.W., et al., The potential of the Geostationary Carbon Cycle Observatory (GeoCarb) to provide multi-scale constraints on the carbon cycle in the Americas, Frontiers in Environmental Science, 6, 2018,

Published 2017

Baker, I.T., et al., Closing the scale gap between land surface parameterizations and GCMs with a new scheme, SiB3-Bins, J. Adv. Mod. Earth Sy., 9 (1), 2017,

Published 2016

Coming soon…

Published 2015

Houweling, S., Baker, D.F., et al., An inter-comparison of inverse models for estimating sources and sinks of CO2 using GOSAT measurements, Journal Geophysical Research – Atmospheres, 2015,

Published 2014

Wang, J.S., …, Baker, D.F., et al., A regional CO2 observing system simulation experiment for the ASCENDS satellite mission, Atmos. Chem. Phys., 2014,

Published 2013

Schuh, A.E., et al, Evaluating atmospheric CO2 inversions at multiple scales over a highly inventoried agricultural landscape, Global Change Biology, 19 (5), 2013,

Baker, I.T., et al., Surface ecophysiological behavior across vegetation and moisture gradients in Amazonia, Agric. For. Meteor., 182-183, 2013,

Berry, J.A.,…, Baker, I.T., et al., A coupled model of the global cycles of carbonyl sulfide and CO2: A possible new window on the carbon cycle, J. Geophys. Res., 118 (2), 2013,

O’Brien, D.M., Polonsky, I., O’Dell, C.W., et al., Testing the polarization model for TANSO-FTS on GOSAT against clear-sky observations of sun-glint over the ocean, IEEE Trans. Geosci. Remote Sens., 51 (12), 2013,

Published 2012

Crisp, D., Fisher, B.M., O’Dell, C.W., …, O’Brien, D.M., …,Polonsky, I., …, Taylor, T.E., et al., The ACOS XCO2 retrieval algorithm, Part 2: Global XCO2 data characterization, Atmos Meas. Tech., 5 (4), 2012,

Frankenberg, C., O’Dell, C.W., L. Guanter, and J. McDuffie, Remote sensing of near-infrared chlorophyll fluorescence from space in scattering atmospheres: implications for its retrieval and interferences with atmospheric CO2 retrievals, Atmos Meas. Tech., 5 (8), 2012,

Frankenberg, C., Hasekamp, O., O’Dell, C.W., et al., Aerosol information content analysis of multi-angle high spectral resolution measurements and its benefit for high accuracy greenhouse gas retrievals, Atmos. Meas. Tech., 5 (7),

Hammerling, D., Michalak, A., O’Dell, C.W., and Kawa, S.R, Global CO2 distributions over land from the Greenhouse Gases Observing Satellite (GOSAT), Geophys. Res. Lett, 39 (8), 2012,

Houweling, S., Badawy, B., Baker, D.F., …, Schuh, A.E., et al., Iconic CO2 time series at risk, Science, 2012,

Lauvaux, T., Schuh, A.E., et al., Network design for mesoscale inversions of CO2 sources and sinks, Tellus B: Chemical and Physical Meteorology, 2012,

Lauvaux, T., Schuh, A. E., et al., Constraining the CO2 budget of the corn belt: exploring uncertainties from the assumptions in a mesoscale inverse system, Atmos. Chem. Phys., 2012,

Nevison, C.D., Baker, D.F., and Gurney, K.R., A methodology for estimating seasonal cycles of atmospheric CO2 resulting from terrestrial net ecosystem exchange (NEE) fluxes using the Transcom T3L2 pulse-response functions, Geosci. Model Dev. Discuss., 2012,

O’Dell, C.W., …, O’Brien, D.M., …, Polonsky, I., …, Taylor, T.E., et al., The ACOS CO2 retrieval algorithm, Part 1: Description and validation against synthetic observations, Atmos. Meas. Tech., 5 (1), 2012,

Oshchepkov, S., …, O’Dell, C.W., et al., Effects of atmospheric light scattering on spectroscopic observations of greenhouse gases from space: Validation of PPDF-based CO2 retrievals from GOSAT, J. Geophys. Res. – Atmospheres, 117 (D12), 2012,

Taylor, T.E., O’Dell, C.W., O’Brien, D.M., et al., Comparison of cloud screening methods applied to GOSAT near-infrared spectra, IEEE Trans. Geosci. Remote Sens, 50 (1), 2012,

Published 2011

Boesch, H., Baker, D.F., et al., Global characterization of CO2 column retrievals from shortwave-infrared satellite observations of the OCO-2 mission, Remote Sens., 2011,

Day, J.O., O’Dell, C.W., et al., Preflight spectral calibration of the Orbiting Carbon Observatory, IEEE Trans. Geosci. Remote Sens., 49 (7), 2011.

O’Dell, C.W., Day, J.O., …, O’Brien, D.M., et al., Preflight radiometric calibration of the Orbiting Carbon Observatory, IEEE Trans. Geosci. Remote Sens., 49 (6), 2011,

Turnbull, J.C., …, Baker, D.F., et al., Atmospheric observations of carbon monoxide and fossil fuel CO2 emissions from East Asia, J.G.R.– Atmos., 2011,

Wunch, D., …, O’Dell, C.W., et al., A method for evaluating bias in global measurements of CO2 total columns from space, Atmos. Chem. Phys., 11 (23), 2011,

Published 2010

Baker, D.F.,…, O’Brien, D.M., et al., Carbon source/sink information provided by column CO2 measurements from the Orbiting Carbon Observatory, Atmos. Chem. Phys., 2010,

Corbin, K. D., …, Schuh, A.E., …, Baker, I.T., Assessing the impact of crops on regional CO2 fluxes and atmospheric concentrations, Tellus, 2010,

Schuh, A.E.,…,Baker, I.T., et al., A regional high-resolution carbon flux inversion of North America for 2004, Biogeosciences, 7, 1625-1644, 2010,

Kuze, A., O’Brien, D.M., Taylor, T.E., Day, J.O., O’Dell, C.W., et al., Vicarious calibration of the GOSAT sensors using the Railroad Valley Desert Playa, IEEE Trans. Geosci. Remote Sens., 49 (5), 2010,

O’Dell, C.W., Acceleration of multiple-scattering, hyperspectral radiative transfer calculations via low-streams interpolation, J. Geophys. Res. – Atmospheres, 115 (D10206), 2010,

Published 2009

Schuh, A.E.,…Baker, I.T., et al., Seeing the forest through the trees: Recovering large-scale carbon flux biases in the midst of small-scale variability, Journal of Geophysical Research – Biogeosciences, 114 (G3), 2009,

Vidot, J., Bennartz, J.R., O’Dell, C.W., et al, CO2 retrieval over clouds from the OCO mission: Model simulations and error analysis, J. Atmos. Oceanic Technol., 26 (6), 1090-1104, 2009,

Published 2008

Gurney, K.R., Baker, D.F., et al., Interannual variations in continental-scale net carbon exchange and sensitivity to observing networks estimated from atmospheric CO2 inversions for the period 1980 to 2005, Global Biogeochem. Cycles, 2008,

Nevison, C.D., …, Baker, D.F., et al., Contribution of ocean, fossil fuel, land biosphere, and biomass burning carbon fluxes to seasonal and interannual variability in atmospheric CO2, J. Geophys. Res.- Biogeosciences, 2008,

Published 2007

Baker, D.F., Climate Change: Reassessing Carbon Sinks, Perspectives, Science, 2007,

Williams, C.A., …, Baker, D.F., Africa and the global carbon cycle, Carbon Balance and Management, 2007,

Published 2006

Baker, D.F., et al., TransCom3 inversion inter-comparison: Interannual variability of regional CO2 sources and sinks, 1988-2003, Global Biogeochem. Cycles, 2006,

Baker, D.F., et al., Variational data assimilation for atmospheric CO2, Tellus-B: Chemical and Physical Meteorology, 2006,

Heidinger, A.K., O’Dell, C.W., et al., The successive order of interaction radiative transfer model, Part I: Model development, J. Appl. Meteorol. Clim., 45 (10), 2006,

O’Dell, C.W., et al., The successive order of interaction radiative transfer model, Part II: Model performance and applications, J. Appl. Meteorol. Clim., 45 (10), 2006,

Published 2005

Bruhwiler, L.M.P., …, Baker, D.F., and Tans, P., An improved Kalman smoother for atmospheric inversions, Atmos. Chem. Phys., 2005,

Published 2004

Gurney, K.R., …, Baker, D.F., et al., Transcom3 inversion inter-comparison: Model mean results for the estimation of seasonal carbon sources and sinks, Global Biogeochem. Cycles, 2004,

Published 2003

Gurney, K.R., …, Baker, D.F., et al., Transcom3 CO2 inversion intercomparison: 1. Annual mean control results and sensitivity to transport and prior flux info, Tellus B: Chemical and Physical Meteorology, 2003,

Published 2002

Gurney, K.R., …, Baker, D.F., et al., Towards robust regional estimates of CO2 sources and sinks using atmospheric transport models, Nature, 2002,

Peylin, P., Baker, D.F., et al., Influence of transport uncertainty on annual mean and seasonal inversions of atmospheric CO2 data, J. Geophys. Res. – Atmospheres, 2002,

Schimel, D., and Baker, D.F., The wildfire factor, News and Views, Nature, 2002,

Published 2001

Pacala, S.W., Hurtt, G.C., Baker, D.F., et al., Consistent land- and atmosphere-based U.S. carbon sink estimates, Science, 2001,

Published 2000

Baker, D.F., An inversion method for determining time-dependent surface CO2 fluxes, in Inverse Methods in Global Biogeochemical Cycles, Geophys. Monogr. Ser., 114, edited by P Kasibhatla et al., pp. 279-293, AGU, Washington, D.C., 2000,


Group Alumni (year of departure)

Emily Bell (2023). Emily completed her Masters degree in the CSU Atmospheric Science department in 2018 under the supervision of Dr. Chris O’Dell. She continued to work within the CIRA Carbon Group through September of 2023, providing analysis of data obtained during the ACT-America campaign and, later, on a simulation based study of biases in the Level 2 Full Physics retrieval. She currently works at NASA’s Global Modeling and Assimilation Office in Greenbelt, Maryland.

Dr. Nicole Jacobs (2023). After obtaining her PhD in Atmospheric Chemistry and Climatology at the Univ. of Alaska, Fairbanks, Niki started a postdoc in October 2020 with Dr. Chris O’Dell, continuing her research on high latitude retrievals of XCO2, as well as a detailed study on the effects of Digital Elevation Models on the full physics retrieval. She left the group in October 2023 for a research position in the Wunch group at the University of Toronto.

Heather Cronk (2022). Heather obtained a Masters in Atmospheric Science in 2009 under the supervision of Prof. Tom Vonderhar. After a brief stint as a high school math teacher, she took several positions related to the pre and post-launch characterization of the S-NPP VIIRS satellite at NASA’s Goddard Spaceflight Center. In 2013 she joined the CloudSat Data Processing Center, housed at CSU CIRA. For a number of years, her time was split between the CDPC and the Carbon Group, where she was responsible for developing data pipelines, algorithms, analysis tools, data products, and documentation. In approximately 2018 she was selected as the Ground System Manager for NASA’s GeoCarb Ground Data Operations Center, located at CSU CIRA. In June 2023 she took a new position as Data Systems Team Lead at the Laboratory for Atmospheric and Space Physics (LASP) in Boulder, Colorado.

Dr. Peter Somkuti (2021). Peter obtained his PhD with the Earth Observation Science group at the University of Leicester (United Kingdom), under the supervision of Prof. Hartmut Bösch. He then joined CSU’s CIRA Carbon group in 2018 for a 2 year post-doc position, focusing on greenhouse gas retrievals from space. He left the CIRA Carbon Group in 2021 to serve as the GeoCarb Deputy Project Scientist. More recently, he took a position at NASA’s Global Modelling and Assimilation Office in Greenbelt, Maryland.

Dr. Robert Nelson (2019). Rob completed his PhD in the CSU Atmospheric Science department in 2019 under the supervision of Dr. Chris O’Dell. His area of focus was the study of CO2 retrievals from OCO-2. After graduation, Rob took a post-doc with the OCO team and is now a Research Scientist at NASA’s Jet Propulsion Laboratory.

Dr. Michael Cheeseman (2018). Michael received his Masters degree at CSU Atmospheric Science department in 2018, advised by Prof. Scott Denning, with technical support from the CIRA Carbon Team. Prior to attending CSU, Michael was a summer research student, at which time he began his collaboration with the CIRA Carbon Group. He received his PhD at CSU in 2021, studying satellite detection of air quality in Prof. Jeff Pierce’s research group.

Andrew Manaster (2016). Andrew completed his Masters degree in the CSU Atmospheric Science department in 2016 under the supervision of Drs. Christian Kummerow and Chris O’Dell. His study focused on cloud feedbacks in the climate system. He is now a researcher at Remote Sensing Systems in Santa Rosa, CA.

Dr. Hannakaisa Lindqvist (2015). Hannakaisa did a post-doc with Dr. Chris O’Dell in January 2014 through June 2015, where she focused on improvements in the radiative transfer for the OCO retrieval algorithm, and performed analysis of GOSAT XCO2 data and is currently head of the Greenhouse Gases and Satellite Methods Group at the Finnish Meteorological Institute (FMI), in Helsinki, Finland.

Dr. Igor Polonsky (2012). Initially working for Professor Graeme Stephens on the CloudSat project, Igor joined the CIRA Carbon group circa 2009 as a Research Scientist specializing in radiative transfer theory and application. In approximately 2012, Igor left CIRA, and is now a researcher at Atmospheric and Environmental Research (AER).

Dr. Denis O’Brien (2012). Denis is considered to be the founder of the CIRA Carbon Research Group. A mathematician by training, he was a pioneer in the field of remote sensing of carbon dioxide from space, publishing several early fundamental papers. While working as a Senior Research Scientist for Professor Graeme Stephens at CSU’s Atmospheric Science Department, Denis secured project funding for NASA’s Orbiting Carbon Observatory algorithm development circa 2006. Shortly thereafter, Dr Chris O’Dell and Mr Tommy Taylor were hired to assist with the OCO effort. In 2012, after loosing his home to a wildfire, Denis relocated back to his native Australia, where he currently resides. At that time Dr. Chris O’Dell became the defacto group leader. As recently as approximately 2020, Denis remained active in the field of greenhouse gas remote sensing, most notably assisting with early GeoCarb efforts.

Dr Jason Day (2009). After receiving his PhD in Physics from the Univ. Wisc., Madison, Jason served a post-doc in the CIRA Carbon Group prior to taking a position on “The Hill” in Washington, D.C. in September 2009 as an AAAS Science and Technology Policy Fellow. In 2011, he served as an AGU/AAAS Congressional Science Fellow to Senator Al Franken, followed by 5 years in the U.S. House of Representatives as a legislative policy advisor. His career in legislative policy continues most recently as a Research Policy Director at the U.S. Department of Defense.

Carbon Group in summer 2017
Back row from left: Heather Cronk, Chris O’Dell, Emily Bell, and Michael Cheeseman
Front row: David Baker, Tommy Taylor, Andrew Schuh, and Rob Nelson

Carbon Group in summer 2014
List of people (left to right): Michael Cheeseman, Andrew Schuh, Andy Manaster, Robert Nelson, Chris O’Dell, Tommy Taylor, and Hannakaisa Lindqvist

Carbon Group in summer 2012
List of people (left to right): David Baker, Andrew Schuh, Rob Nelson, Chris O’Dell, Tommy Taylor, Igor Polonsky, Denis O’Brien and Tom Oda.

Carbon Team:

Carbon Team
  • (970)556-8646
  • Carbon Team

    Chris O’Dell

    Senior Research Scientist/Scholar

    CIRA Fellow

  • 970.491.8973
  • Carbon Team

    Andrew Schuh

    Research Scientist/Scholar III

  • 970-491-8546
  • Carbon Team
  • 970.491.8546