Assessing emission, transport, atmospheric chemistry, and deposition processes of mercury (Hg) is vital to understanding the impact of mercury pollution on the environment and human health. Factors such as emission uncertainties, transport mechanisms, a chemical fate, including accumulation and toxicity to living organisms complicate the problem of mercury in the environment. (Clarkson 1993) Over the last decades, significant advances in the determination of speciation, deposition, and transport of atmospheric mercury have been made with the increasing number of studies on the estimation of mercury dry and wet deposition. Yet, there is still a significant gap in knowledge of mercury dry and wet deposition and identification of geographical patterns. This research builds on previous studies conducted by Risch and Kenski (2018), L. Zhang et al. (2016), L. Zhang et al. (2012), X. Zhang et al. (2012) showing that Hg dry deposition was a significant contributor to the overall Hg load at North American sites.

In order to advance the state of the science, this study aims to presents a new product for NADP that includes an estimate of total mercury wet deposition data obtained from Mercury Deposition Network (MDN) and estimated dry deposition for the Atmospheric Mercury Network (AMNet) sites. Atmospheric mercury dry deposition in different land cover around 12 sites in North America was estimated using AMNet data for the year 2017. Sites were selected based on data quality and data record completeness for MDN and AMNet network locations. The main contribution of this study is the establishment of variability assessment and geographical patterns of Hg dry and wet deposition over the dominant land cover, along with the relative importance of dry and wet deposition. The results will demonstrate the application of using ambient Hg measurements to develop an annual dry deposition estimate for AMNet network sites.