Influence of large‐scale teleconnection patterns on methane sulfonate ice core records in Dronning Maud Land

Abstract

Records of methane sulfonate (MS−) in ice cores from the high plateau of Dronning Maud Land (DML), Antarctica, drilled in the framework of the European Project for Ice Coring in Antarctica, are investigated for their potential as an environmental and climate archive for the Atlantic sector of the Southern Ocean. Despite postdepositional changes, years of extraordinary MS− concentrations can be clearly detected in the ice core records. We use composite anomaly maps of atmospheric parameters from the National Centers for Environmental Prediction/National Center for Atmospheric Research reanalysis fields for years of extreme MS− concentration to detect atmospheric patterns causing MS− variability. Changing atmospheric transport is shown to be an important, but not exclusive, parameter being conserved in the MS− record in DML. The often hypothesized direct link between high MS− concentrations and El Niño events is not supported for the observed region whereas the Antarctic Dipole (ADP), which is modulated by El Niño–Southern Oscillation conditions, exerts significant influence. A clear 13.9‐year cycle can be found throughout a 2000‐year MS− record that can be related to variations in the ADP. Over the last 300 years a 4.6‐year cycle is revealed in the MS− (and sea‐salt record), which vanishes in the deeper part of the ice core as a consequence of diffusion processes. From the long‐term perspective, periods of high MS− concentrations are connected to, on average, higher sea‐salt aerosol as well, reflecting a seasonally independent influence of transport on both species. A distinctive period of efficient atmospheric transport, probably due to a pronounced ADP, could be found from 1200 to 1600 A.D.

Continuous 25-yr aerosol records at coastal Antarctica– I: inter-annual variability of ionic compounds and links to climate indices

“…In this context, the most meaningful ionic impurities have proved to be the marine biogenic methanesulfonate (MS), non–sea salt sulphate (nss‐) that is mainly biogenic or sporadically of volcanic origin, and Na + , a genuine sea salt tracer. From Antarctic ice core records of these ions attempts were made to deduce the history of sea ice extent (Curran et al, 2003; Abram et al, 2007; Becagli et al, 2009), marine bio‐productivity (Rhodes et al, 2009), as well as the southern atmospheric circulation pattern, including the Southern Annular Mode (SAM), Antarctic Dipole (ADP), Antarctic Circumpolar wave (ACW) and El Niño teleconnection (Fischer et al, 2004; Fundel et al, 2006; Mayewski et al, 2009). On the other hand, Russell and McGregor (2009) concluded that the paleoatmospheric circulation reconstructions from ice core data appeared disturbingly inconsistent.…”

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

“…The observational literature has not yet established which processes govern MSA deposition in Antarctica and the spatial extent over which such relationships hold. In addition to sea ice, MSA concentrations have also been linked to changes in atmospheric circulation [e.g., Becagli et al , 2009; Fundel et al , 2006]. The extent to which MSA is influenced by sea ice compared to atmospheric circulation may be regionally dependent.…”

Crystallization and Characterization of Magnesium Methanesulfonate Hydrate Mg(CH3SO3)2·12H2O

“…DMS is produced by processes involving phytoplankton, and it is highly volatile and released to the atmosphere. 11,12 In ice cores, MSA is deposited as methanesulfonate salts 13 rather than in acid form, probably due to its fixation on alkaline particles of marine or continental origin during the glacial period.…”