The monitoring of atmospheric mercury species in the Southern Indian Ocean at Amsterdam Island (38°S)

Abstract. Although essential to fully understand the cycling of mercury at the global scale, mercury species records in the Southern Hemisphere are scarce. Under the framework of the Global Mercury Observation System (GMOS) project, a monitoring station has been set up on Amsterdam Island (37°48´ S, 77°34´ E) in the remote southern Indian Ocean. For the first time in the Southern Hemisphere, a 2-year record of gaseous elemental mercury (GEM), reactive gaseous mercury (RGM) and particle-bound mercury (PBM) is presented. GEM concentrations were remarkably steady (1.03 ± 0.08 ng m−3) while RGM and PBM concentrations were very low and exhibited a strong variability (mean: 0.34 pg m−3, range: < detection limit–4.07 pg m−3; and mean: 0.67 pg m−3, range: < detection limit–12.67 pg m−3, respectively). Despite the remoteness of the island, wind sector analysis, air mass back trajectories and the observation of radonic storms highlighted a long-range contribution from the southern African continent to the GEM and PBM budgets from July to September during the biomass burning season. Low concentrations of GEM were associated with southerly polar and marine air masses from the remote southern Indian Ocean. This unique data set provides new baseline GEM concentrations in the Southern Hemisphere midlatitudes while mercury speciation along with upcoming wet deposition data will help to improve our understanding of the mercury cycle in the marine boundary layer.

Download Full-text

A 2 year record of atmospheric mercury species at a background Southern Hemisphere station on Amsterdam Island

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-14-14439-2014 ◽

2014 ◽

Vol 14 (10) ◽

pp. 14439-14470

Author(s):

H. Angot ◽

M. Barret ◽

O. Magand ◽

M. Ramonet ◽

A. Dommergue

Keyword(s):

Indian Ocean ◽

Southern Hemisphere ◽

Marine Boundary Layer ◽

Elemental Mercury ◽

Atmospheric Mercury ◽

Southern Indian Ocean ◽

Observation System ◽

Mercury Species ◽

Back Trajectories ◽

Gaseous Elemental Mercury

Abstract. Scarcity of mercury species records in the Southern Hemisphere is a critical weak point for the development of appropriate modeling and regulation scenarios. Under the framework of the "Global Mercury Observation System" (GMOS) project, a monitoring station has been set up on Amsterdam Island (37°48' S, 77°34' E) in the remote southern Indian Ocean. For the first time in the Southern Hemisphere, a 2 year record of gaseous elemental mercury (GEM), reactive gaseous mercury (RGM) and particle-bound mercury (PBM) is presented. GEM concentrations were remarkably steady (1.03 ± 0.08 pg m−3) while RGM and PBM concentrations were very low and exhibited a strong variability (mean: 0.34 pg m−3 [range: 0.28–4.07 pg m−3] and mean: 0.67 pg m−3 [range: 0.28–12.67 pg m−3], respectively). Despite the remoteness of the island, wind sector analysis, air mass back trajectories and the observation of radonic storms highlighted a long-range contribution from the southern African continent to the GEM and PBM budgets in winter during the biomass burning season. Lowest concentrations of GEM were associated with southerly polar and marine air masses from the remote southern Indian Ocean. This unique dataset provides new baseline GEM concentrations in the Southern Hemisphere mid-latitudes for further modeling studies, while mercury speciation along with upcoming wet deposition data will help improving our understanding of mercury cycle in the marine boundary layer.

Download Full-text

AN ABERRANTLY PIGMENTED SOUTHERN ELEPHANT SEAL (MIROUNGA LEONINA) AT ILES KERGUELEN, SOUTHERN INDIAN OCEAN

Marine Mammal Science ◽

10.1111/j.1748-7692.2000.tb00964.x ◽

2000 ◽

Vol 16 (3) ◽

pp. 681-684 ◽

Cited By ~ 8

Author(s):

Joel Bried ◽

Daniel Haubreux

Keyword(s):

Indian Ocean ◽

Elephant Seal ◽

Southern Indian Ocean ◽

Southern Elephant Seal ◽

Mirounga Leonina

Download Full-text

Distribution of atmospheric mercury species near ground

Environmental Science & Technology ◽

10.1021/es60097a004 ◽

1974 ◽

Vol 8 (12) ◽

pp. 1003-1009 ◽

Cited By ~ 88

Author(s):

David L. Johnson ◽

Robert S. Braman

Keyword(s):

Atmospheric Mercury ◽

Mercury Species

Download Full-text

Life history characteristics ofAlticus monochrus, a supratidal blenny of the southern Indian Ocean

African Zoology ◽

10.1080/15627020.2006.11407330 ◽

2006 ◽

Vol 41 (1) ◽

pp. 1-7 ◽

Cited By ~ 3

Author(s):

M. Bhikajee ◽

J. M. Green ◽

R. Dunbrack

Keyword(s):

Life History ◽

Indian Ocean ◽

Southern Indian Ocean ◽

Life History Characteristics

Download Full-text

Simulation of atmospheric mercury depletion events (AMDEs) during polar springtime using the MECCA box model

Atmospheric Chemistry and Physics ◽

10.5194/acp-8-7165-2008 ◽

2008 ◽

Vol 8 (23) ◽

pp. 7165-7180 ◽

Cited By ~ 35

Author(s):

Z.-Q. Xie ◽

R. Sander ◽

U. Pöschl ◽

F. Slemr

Keyword(s):

Aqueous Phase ◽

Ozone Depletion ◽

Elemental Mercury ◽

Atmospheric Mercury ◽

Box Model ◽

Rate Coefficients ◽

Mercury Species ◽

Phase Reaction ◽

Gaseous Elemental Mercury ◽

Sea Salt Aerosol

Abstract. Atmospheric mercury depletion events (AMDEs) during polar springtime are closely correlated with bromine-catalyzed tropospheric ozone depletion events (ODEs). To study gas- and aqueous-phase reaction kinetics and speciation of mercury during AMDEs, we have included mercury chemistry into the box model MECCA (Module Efficiently Calculating the Chemistry of the Atmosphere), which enables dynamic simulation of bromine activation and ODEs. We found that the reaction of Hg with Br atoms dominates the loss of gaseous elemental mercury (GEM). To explain the experimentally observed synchronous depletion of GEM and O3, the reaction rate of Hg+BrO has to be much lower than that of Hg+Br. The synchronicity is best reproduced with rate coefficients at the lower limit of the literature values for both reactions, i.e. kHg+Br≈3×10−13 and kHg+BrO≤1×10−15 cm3 molecule−1 s−1, respectively. Throughout the simulated AMDEs, BrHgOBr was the most abundant reactive mercury species, both in the gas phase and in the aqueous phase. The aqueous-phase concentrations of BrHgOBr, HgBr2, and HgCl2 were several orders of magnitude larger than that of Hg(SO3)22−. Considering chlorine chemistry outside depletion events (i.e. without bromine activation), the concentration of total divalent mercury in sea-salt aerosol particles (mostly HgCl42−) was much higher than in dilute aqueous droplets (mostly Hg(SO3)22−), and did not exhibit a diurnal cycle (no correlation with HO2 radicals).

Download Full-text

Continuous flow analysis of the Mount Brown South ice core

10.5194/egusphere-egu21-15782 ◽

2021 ◽

Author(s):

Margaret Harlan ◽

Helle Astrid Kjær ◽

Tessa Vance ◽

Paul Vallelonga ◽

Vasileios Gkinis ◽

...

Keyword(s):

Indian Ocean ◽

Size Distribution ◽

Continuous Flow ◽

Ice Core ◽

Flow Analysis ◽

East Antarctica ◽

Southern Indian Ocean ◽

Indian Ocean Region ◽

Continuous Flow Analysis ◽

Ocean Region

The Mount Brown South (MBS) ice core is an approximately 300-meter-long ice core, drilled in 2016-2017 to the south of Mount Brown, Wilhelm II Land, East Antarctica. This location in East Antarctica was chosen as it produces an ice core with well-preserved sub-annual records of both chemistry and isotope concentrations, spanning back over 1000 years. MBS is particularly well suited to represent climate variations of the Indian Ocean sector of Antarctica, and to provide information about regional volcanism in the Southern Indian Ocean region.A section of ice spanning the length of the MBS core was melted as part of the autumn 2019 continuous flow analysis (CFA) campaign at the Physics of Ice, Climate, and Earth (PICE) group at the University of Copenhagen. During this campaign, measurements were conducted for chemistry and impurities contained in the ice, in addition to water isotopes. The data measured in Copenhagen include measurements of H2O2, pH, electrolytic conductivity, and NH4+, Ca2+, and Na+&#160;ions, in addition to insoluble particulate concentrations and size distribution measured using an Abakus laser particle counter.Here, we present an overview of the CFA chemistry and impurity data, as well as preliminary investigations into the size distribution of insoluble particles and the presence of volcanic material within the ice. These initial chemistry and particulate size distribution data sets are useful in order to identify sections of the MBS core to subject to further analysis to increase our understanding of volcanic activity in the Southern Indian Ocean region.

Download Full-text