Long-term low-level Arctic aerosol trends, analysis, and climatological correlations at Alert, Canada
Three decades of weekly winter low-level Arctic aerosol samples from Alert, Canada, are analyzed using Neutron Activation Analysis (NAA) in the TRIGA reactor at the University of Texas. The samples are from the longest currently-running Arctic aerosol data collection project and have received only limited analysis to date. The elemental composition (Aluminum, Bromine, Calcium, Chlorine, Copper, Iodine, Magnesium, Manganese, Sodium, Titanium, and Vanadium) is determined for each sample. The elemental results are characterized statistically and the results are compared to climatological data including temperature data, sea ice data, ice shelf data, and snow cover data. Positive Matrix Factorization (PMF) is performed on the complete data set to determine primary sources of the aerosol pollution. Other data from Alert, including Methanesulphonic Acid (MSA), Iron, and Sulphate data, is compared to the NAA results, and additional PMF is performed with the additional data. Results show many expected as well as unexpected trends and correlations including correlations with ice cover and temperature trends, correlations to decreasing anthropogenic pollution, and long-term trends of sea components and sea-component ratios in the aerosol. PMF results conclude that there are 5 predominant sources of the Arctic aerosol including two sea sources, two predominant anthropogenic sources (combustion and industrial), and a crustal component. This particular area of inquiry represents completely new information in the growing body of climate science and may influence studies that relate to the Arctic climate and environment, and should have an impact on the particular fields of Arctic Aerosol Monitoring, Atmospheric Transport, Global Diffusion and Dispersion, Arctic Climate Science, and Pollution Monitoring.