Chemical cycling and deposition of atmospheric mercury in polar regions: review of recent measurements and comparison with models
Journal article, 2016
Mercury (Hg) is a worldwide contaminant that can cause adverse health effects to wildlife and humans. While atmospheric modeling traces the link from emissions to deposition of Hg onto environmental surfaces, large uncertainties arise from our incomplete understanding of atmospheric processes (oxidation pathways, deposition, and re-emission). Atmospheric Hg reactivity is exacerbated in high latitudes and there is still much to be learned from polar regions in terms of atmospheric processes. This paper provides a synthesis of the atmospheric Hg monitoring data available in recent years (2011-2015) in the Arctic and in Antarctica along with a comparison of these observations with numerical simulations using four cutting-edge global models. The cycle of atmospheric Hg in the Arctic and in Antarctica presents both similarities and differences. Coastal sites in the two regions are both influenced by springtime atmospheric Hg depletion events and by summertime snowpack re-emission and oceanic evasion of Hg. The cycle of atmospheric Hg differs between the two regions primarily because of their different geography. While Arctic sites are significantly influenced by northern hemispheric Hg emissions especially in winter, coastal Antarctic sites are significantly influenced by the reactivity observed on the East Antarctic ice sheet due to katabatic winds. Based on the comparison of multi-model simulations with observations, this paper discusses whether the processes that affect atmospheric Hg seasonality and inter-annual variability are appropriately represented in the models and identifies research gaps in our understanding of the atmospheric Hg cycling in high latitudes.
Author
H. Angot
Grenoble Alpes University
A. Dastoor
Environment Canada
F. De Simone
National Research Council of Italy (CNR)
Katarina Gårdfeldt
Chalmers, Chemistry and Chemical Engineering, Energy and Material
C. N. Gencarelli
National Research Council of Italy (CNR)
I. M. Hedgecock
National Research Council of Italy (CNR)
Sarka Langer
IVL Swedish Environmental Research Institute
O. Magand
LGGE Laboratoire de Glaciologie et Geophysique de l'Environnement
Grenoble Alpes University
Michelle Nerentorp
Chalmers, Chemistry and Chemical Engineering, Energy and Material
C. Nordstrom
Danmarks Miljoundersogelser
K. A. Pfaffhuber
Norwegian Institute for Air Research (NILU)
N. Pirrone
National Research Council of Italy (CNR)
A. Ryjkov
Environment Canada
N. E. Selin
Massachusetts Institute of Technology (MIT)
H. Skov
Danmarks Miljoundersogelser
S. J. Song
Massachusetts Institute of Technology (MIT)
F. Sprovieri
National Research Council of Italy (CNR)
A. Steffen
Environment Canada
K. Toyota
Environment Canada
O. Travnikov
Meteorological Synthesizing Centre
X. Yang
British Antarctic Survey
A. Dommergue
Grenoble Alpes University
LGGE Laboratoire de Glaciologie et Geophysique de l'Environnement
Atmospheric Chemistry and Physics
1680-7316 (ISSN) 1680-7324 (eISSN)
Vol. 16 16 10735-10763Driving Forces
Sustainable development
Subject Categories (SSIF 2011)
Earth and Related Environmental Sciences
DOI
10.5194/acp-16-10735-2016