Up-scaling mercury emissions from terrestrial surfaces as a response to sustained temperature increase

It has been well established that human activities have significantly altered the earth's climate system. Terrestrial Mercury (Hg) emissions exhibit a strong relationship with meteorological variables, in particular solar radiation and temperature. Alterations to these controlling parameters resulting from climate change will influence Hg air-surface exchange trends. Over the past two decades, using the same micrometeorological-based methodology, mercury flux data was collected at a number of varying terrestrial sites globally. This study aimed to investigate the relationship between climate variables and mercury air-surface exchange. The large data set identified significant relationships between Hg air-surface exchange and temperature that was consistent across the multiple field sites, facilitating the development of a well-constrained empirical model to predict the impact of climate change on terrestrial mercury air-surface exchange, with changing temperature. Flux increases calculated, based on IPCC Temperature projections, ranged between 15 and 43% increase for a 1–2 °C rise in temperature by 2050 and 15–96% increase for temperature rise between 1 and 3.7 °C by 2100. The projections developed here indicate that air temperature can be used as a baseline for determining potential terrestrial evasion under projected climate change, prolonging the recovery time of the natural mercury cycle in view of reduced anthropogenic emissions.