Evaluation of Modeled Carbon Monoxide and Methane Columns in the High Arctic Using TCCON Measurements

Methane (CH4) and carbon monoxide (CO) are gases with important climate impacts as direct and indirect greenhouse gases, respectively. Methane has a warming potential 28 times that of carbon dioxide on a 100-year timescale, and carbon monoxide is a precursor to ozone in the troposphere. Modeling trace gas concentrations in the Arctic atmosphere can be challenging due to Arctic conditions and sensitivity to long-range transport, and comparing model outputs to remote sensing measurements is essential for ensuring that models are performing well. Ground-based Arctic measurements are spatially sparse, so it is important to make use of all such available data sets. In this study, we assess eight atmospheric models, comparing their simulations of atmospheric CO and CH4 column-averaged dry-air mole fractions for 2014 and 2015 with ground-based retrievals of these species at three Arctic stations in the Total Carbon Column Observing Network (TCCON). The multi-model mean had mean biases (± one standard deviation of the mean) of −5.4% ± 8% at Eureka, Canada, −6.5% ± 8% at Ny-Ålesund, Norway, and −11% ± 7% at Sodankylä, Finland for CO, and mean biases of −0.25% ± 0.5% at Eureka, −0.90% ± 0.5% at Ny-Ålesund, and −1.0% ± 0.5% at Sodankylä for CH4. Individual model mean biases range from −33% to +35% for CO and −2.5% to +1.9% for CH4. These results indicate that models could benefit from improvements targeting simulations of Arctic CO.

MCGEE Erin;  STRONG Kimberly;  WALKER Kaley A.;  WHALEY Cynthia;  KIVI Rigel;  NOTHOLT Justus;  CASSIDY Gabriel;  BEAGLEY Stephen;  CHIEN Rong-You;  DOBRICIC Srdan;  DONG Xinyi;  FU Joshua;  GAUSS Michael;  GONG Wanmin;  LANGNER Joakim;  LAW Kathy S.;  MARELLE Louis;  ONISHI Tatsuo;  OSHIMA Naga;  PLUMMER David;  POZZOLI Luca;  RAUT Jean-Christophe;  TSYRO Svetlana; 

2025-11-20

AMER GEOPHYSICAL UNION

JRC133523

2169-8996 (online),   

https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2025JD043489,    https://publications.jrc.ec.europa.eu/repository/handle/JRC133523,   

10.1029/2025JD043489 (online),