Short-Lived Climate Forcers (SLCFs) are atmospheric species with climate impacts and lifetimes shorter than that of carbon dioxide; they are a major subject of interest of the Arctic Monitoring and Assessment Programme (AMAP), a working group of the Arctic Council, and were the focus of the 2021 AMAP Assessment Report. AMAP studies and documents the effects of climate change and pollution on Arctic climate with the intent of informing policy recommendations. AMAP used multiple models to determine levels of SLCFs in the Arctic; these models include CESM, CMAM, DEHM, EMEP-MSC-W, GEM-MACH, GEOS-Chem, MATCH, MATCH-SALSA, MRI-ESM2, UKESM1, and WRF-Chem. The present study compares carbon monoxide and methane outputs from these models, where possible, to data from ground-based Fourier Transform Infrared (FTIR) Spectrometers focused on the near-infrared spectral region. These spectrometers are part of the Total Carbon Column Observing Network (TCCON), with Arctic stations in Eureka (Nunavut, Canada), Ny Ålesund (Spitzbergen, Norway), and Sodankylä (Finland). TCCON has been used for many validation studies in the past due to it having very low site-to-site bias. The model outputs are 3-D mixing ratios given at three-hour intervals for the years 2014 and 2015; these are sampled at TCCON locations and smoothed using TCCON averaging kernels in order to be compared to the TCCON column-averaged dry air mole fraction (Xgas) data product. We evaluate the AMAP models against TCCON observations to assess their ability to simulate carbon monoxide and methane in the High Arctic, and ultimately better understand their suitability for informing SLCF policy decisions.
Host: Christian DiMaria