Modeled methanesulfonic acid (MSA) deposition in Antarctica and its relationship to sea ice

In remote marine areas, biogenic productivity and atmospheric particulate are coupled through dimethylsulfide (DMS) emission by phytoplankton. Once in the atmosphere, the gaseous DMS is oxidized to produce H2SO4 and methanesulfonic acid (MSA); both species can affect the formation of cloud condensation nuclei. This study analyses eight years of biogenic aerosol evolution and variability at two Arctic sites: Thule (76.5° N, 68.8° W) and Ny Ålesund (78.9° N, 11.9° E). Sea ice plays a key role in determining the MSA concentration in polar regions. At the beginning of the melting season, in April, up to June, the biogenic aerosol concentration appears inversely correlated with sea ice extent and area, and positively correlated with the extent of the ice-free area in the marginal ice zone (IF-MIZ). The upper ocean stratification induced by sea ice melting might have a role in these correlations, since the springtime formation of this surface layer regulates the accumulation of phytoplankton and nutrients, allowing the DMS to escape from the sea to the atmosphere. The multiyear analysis reveals a progressive decrease in MSA concentration in May at Thule and an increase in July August at Ny Ålesund. Therefore, while the MSA seasonal evolution is mainly related with the sea ice retreat in April, May, and June, the IF-MIZ extent appears as the main factor affecting the longer-term behavior of MSA.

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Coastal ice-core record of recent northwest Greenland temperature and sea-ice concentration

Journal of Glaciology ◽

10.3189/2015jog15j054 ◽

2015 ◽

Vol 61 (230) ◽

pp. 1137-1146 ◽

Cited By ~ 11

Author(s):

Erich C. Osterberg ◽

Robert L. Hawley ◽

Gifford Wong ◽

Ben Kopec ◽

David Ferris ◽

...

Keyword(s):

Sea Ice ◽

Regional Climate ◽

Ice Core ◽

Methanesulfonic Acid ◽

Ice Cores ◽

Snow Accumulation ◽

Multilinear Regression ◽

Sea Ice Concentration ◽

Baffin Bay ◽

Ice Concentration

AbstractCoastal ice cores provide an opportunity to investigate regional climate and sea-ice variability in the past to complement hemispheric-scale climate reconstructions from ice-sheet-interior ice cores. Here we describe robust proxies of Baffin Bay temperature and sea-ice concentration from the coastal 2Barrel ice core collected in the Thule region of northwest Greenland. Over the 1990–2010 record, 2Barrel annually averaged methanesulfonic acid (MSA) concentrations are significantly correlated with May–June Baffin Bay sea-ice concentrations and summer temperatures. Higher MSA is observed during warmer years with less sea ice, indicative of enhanced primary productivity in Baffin Bay. Similarly, 2Barrel annually averaged deuterium excess (d-excess) values are significantly correlated with annual Baffin Bay sea-ice concentrations and summer and annual temperatures. Warm (cool) years with anomalously low (high) sea-ice concentration are associated with proportionally more (less) low-d-excess Baffin Bay moisture at the ice-core site. Multilinear regression models incorporating 2Barrel MSA, d-excess and snow accumulation account for 38–51% of the Baffin Bay sea-ice and temperature variance. The annual temperature model is significantly correlated with temperatures throughout most of Greenland and eastern Arctic Canada due to the strong influence of the North Atlantic Oscillation and Atlantic Multidecadal Oscillation.

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Sulfur-containing species in a snow pit in the Lambert Glacier basin, East Antarctica

Annals of Glaciology ◽

10.3189/172756499781820978 ◽

1999 ◽

Vol 29 ◽

pp. 84-88 ◽

Cited By ~ 1

Author(s):

Sun Junying ◽

Ren Jiawen ◽

Qin Dahe ◽

Wang Xiaoxiang

Keyword(s):

Sea Ice ◽

Methanesulfonic Acid ◽

Volcanic Eruptions ◽

Sea Salt ◽

The South ◽

South Indian ◽

The Mean ◽

Total Sulfate ◽

Lambert Glacier ◽

Lambert Glacier Basin

AbstractA 2.7 m snow pit was sampled in the Lambert Glacier basin, about 650 km from the coast. Concentrations of methanesulfonic acid (MSA) and non-sea-salt SO42- (nssSO42-) show distinct variation with depth in the snow pit. The seasonal variation of MSA is used to date the snow-pit samples. MSA concentration is in the range 1.922.0 μgkg−1 with a mean of 7.0 μgkg-1. The mean nssSO42- concentration is 41.5 μgkg−1 with a range of 0-87 μgkg−1. The nssSO42- ∼ concentration was calculated by subtracting the sea-salt sulfate contribution using Nai as a conservative tracer. The nssSO42– contributes about 80% of the total sulfate in the snow pit. The mean mass ratio of MSA to nssSO42- 0.176, is much higher than that measured in the low to mid-latitudes, but is very close to the ratio in snow at the South Pole. El Chichon and Hudson volcanic eruptions do not significantly perturb the nssS042- concentrations at this site. MSA concentrations are anticorrelated with sea-ice area for the South Indian Ocean sector between 40° and 90° E, suggesting enhanced MSA production accompanying low sea-ice coverage.

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Changes in climate, ocean and ice-sheet conditions in the Ross embayment, Antarctica, at 6 ka

Annals of Glaciology ◽

10.3189/1998aog27-1-305-310 ◽

1998 ◽

Vol 27 ◽

pp. 305-310 ◽

Cited By ~ 51

Author(s):

Eric J. Steig ◽

Charles P. Hart ◽

James W. C. White ◽

Wendy L. Cunningham ◽

Mathew D. Davis ◽

...

Keyword(s):

Sea Ice ◽

Late Holocene ◽

Environmental Changes ◽

Ross Sea ◽

Ice Core ◽

Sediment Cores ◽

Methanesulfonic Acid ◽

Ice Shelf ◽

Radiocarbon Dates ◽

Ice Shelves

Evidence from the Ross embayment, Antarctica, suggests an abrupt cooling and a concomitant increase in sea-ice cover at about 6000 BP (6 ka). Stable-isotope (δD) concentrations in the Taylor Dome ice core, at the western edge of the Ross embayment, decline rapidly after 6 ka, and continue to decline through the late Holocene. Methanesulfonic acid concentrations at Taylor Dome show opposite trends to δD Sediment cores from the western Ross Sea show a percentage minimum for the sea-ice diatom Fragilariopsis curta between 9 and 6 ka, whenTaylor Dome δD values are highest, followed by an increase through the late Holocene. Radiocarbon dates from raised beach deposits indicate that the retreat of ice shelves in the Ross embayment ceased at about 6 ka, coincident with the environmental changes inferred from the sediment and ice-core records. The similarity in timing suggests an important role for climate in controlling the evolution of ice-shelf margins following the end of the last glaciation.

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The methanesulfonic acid (MSA) record in a Svalbard ice core

Annals of Glaciology ◽

10.3189/172756405781812637 ◽

2005 ◽

Vol 42 ◽

pp. 345-351 ◽

Cited By ~ 30

Author(s):

Elisabeth Isaksson ◽

Teija Kekonen ◽

John Moore ◽

Robert Mulvaney

Keyword(s):

Sea Ice ◽

Dimethyl Sulfide ◽

Barents Sea ◽

Ice Core ◽

Methanesulfonic Acid ◽

Ice Cores ◽

Climatic Conditions ◽

Temperature Record ◽

Decadal Scale ◽

The 19Th Century

AbstractSvalbard ice cores have not yet been fully exploited for studies of climate and environmental conditions. In one recently drilled ice core from Lomonosovfonna, we have studied the methanesulfonic acid (MSA) records in relation to temperature and sea ice. Under the present climatic conditions, MSA appears to be negatively correlated with the sea-ice conditions in the Barents Sea, and positively correlated with the instrumental temperature record from Svalbard. However, prior to about 1920 the MSA concentrations were about twice as high, despite the more extensive sea-ice coverage. After exploring different possibilities, we suggest that MSA concentrations were higher in the 19th century than in the 20th century due to increased primary production, in response to increased vertical stability of the sea surface layers, caused by increased meltwater production from the more extensive sea-ice cover. Thus, the MSA record from Lomonosovfonna probably both is a measure of the regional sea-ice variability on the multi-decadal scale and reflects locally favorable conditions for marine biogenic dimethyl sulfide (DMS) production on the sub-decadal scale.

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