Abstracts

Identifying the potential influence of climate change on mercury air-surface exchange

by Katrina Macsween

Human activities over the last few centuries have altered the earth's climate system and added to the global mercury budget. In order to understand how future climate predictions may influence future mercury emissions it is important to first understand how current climate parameters influence mercury exchange from different surfaces. This research aimed to investigate the relationship between climate controls and mercury air-surface exchange and determine the potential implications of these findings with future climate change. Mercury flux data was obtained for a number of sites using micrometeorological methods and comprised of both background and enriched sites. The Arrhenius equation was applied to gain a better understanding of which parameters control mercury flux. Environmental parameters were ffound to have a significant relationship with Hg air-surface exchange at the study sites. Interactions between the parameters and the Hg fluxes varied depending on sites and classification. Flux adjustments indicated that with temperature increase it is likely there will be an increase in Hg emissions from natural substrates. Flux increases calculated here range between a 30 and 40% increase for a 1 to 2⁰C rise in temperature by 2050 and a 30 to 52% increase for temperature rise between 1 and 3.7⁰C by 2100.