Using 20 years of high-resolution satellite data, we present quantitative evidence that High-Latitude Dust (HLD) sources to the atmosphere are widespread across the "Canadian Arctic Dust Belt". Our results motivate atmospheric model development to include HLD sources, while our data provides an observational basis for evaluating such improved models. The Arctic is a fragile region experiencing 3–4 greater warming than global average and HLD is of significance to that warming.

Nineteen years of atmospheric composition measurements made at the University of Toronto Atmospheric Observatory (TAO; 43.66° N, 79.40° W; 174 m.a.s.l.) are presented. These are retrieved from Fourier transform infrared (FTIR) solar absorption spectra recorded with a spectrometer from May 2002 to December 2020. The retrievals have been optimized for fourteen species: O₃, HCl, HF, HNO₃, CH₄, C₂H₆, CO, HCN, N₂O, C₂H₂, H₂CO, CH₃OH, HCOOH, and NH₃.

The MOPITT instrument has been measuring atmospheric carbon monoxide (CO) from space since 2000. Its data products are valuable for CO trend analysis. This paper compares products with different spatial resolutions to identify discrepancies in mean CO amounts and detectable trends for coastal grid boxes. It is found that CO amounts and trends differ significantly between data products for a large number of these grid boxes, essentially due to how the coarser-resolution products are created.