Surge in sulphur and halogen degassing from Ambrym volcano, Vanuatu

Abstract

Volcanoes provide important contributions to atmospheric budgets of SO 2 and reactive halogens, which play significant roles in atmospheric oxidative capacity and radiation. However, the global source strengths of volcanic emissions remain poorly constrained. These uncertainties are highlighted here by the first measurements of gas emission rates from Ambrym volcano, Vanuatu. Our initial airborne ultraviolet spectroscopic measurements made in January 2005 indicate fluxes of 18-270 kg s -1 of SO 2 , and 62-110 gs -1 of BrO, into the atmosphere, placing Ambrym amongst the largest known contemporary point sources of both these species on Earth. We also estimate high Cl and F fluxes of~8-14 and~27-50 kg s -1 , respectively, for this period. Further observations using both airborne and spaceborne remote sensing reveal a fluctuating SO 2 output between 2004 and 2008, with a surge in the first half of 2005, and underline the substantial contribution that a single passively degassing volcano can make to the atmospheric budget of sulfur and halogens.

Gases in Volcanic Lake Environments

“…It is well recognised that many volcanoes emit large quantities of gas in the absence of significant eruption activity, including Etna (Aiuppa et al 2007); Popocatépetl (Delgado-Granados et al 2001), Ambrym (Bani et al 2009), Miyakejima (Shinohara et al 2003) and a wide range of less prodigeous emitters, some including volcanic lakes (e.g., Aso, Shinohara et al this issue), White (after Giggenbach 1996). CO 2 is relatively insoluble in melts, having a bulk solubility similar to that of the noble gases Island (Werner et al 2008), Poás (Rowe et al 1992), and Ruapehu (Christenson 2000.…”

New clues on the contribution of Earth’s volcanism to the global mercury cycle

“…Ambrym is the most active volcano in the Vanuatu chain (South Pacific), and is world famous for its commonly active lava lakes within the two main active cones, Bembow and Marum (Table 1). Activity at Ambrym volcano ranges from lava lake degassing confined to the summit craters, to dense ash-rich eruptions producing cropdamaging acid rain across the island (Cronin and Sharp 2002;Robin et al 1993;Bani et al 2009). Open-vent magmatic degassing at this volcano sustains a strong gas plume (Allard et al 2008;Bani et al 2009).…”

“…Activity at Ambrym volcano ranges from lava lake degassing confined to the summit craters, to dense ash-rich eruptions producing cropdamaging acid rain across the island (Cronin and Sharp 2002;Robin et al 1993;Bani et al 2009). Open-vent magmatic degassing at this volcano sustains a strong gas plume (Allard et al 2008;Bani et al 2009). Yasur (southern Vanuatu, Tanna Island) is one of the world's most active volcanoes, and is characterised by persistent strombolian activity and degassing, producing an ash-laden plume whose compositional features have only recently been characterised (Bani and Lardy 2007).…”

SO<sub>2</sub> and BrO observation in the plume of the Eyjafjallajökull volcano 2010: CARIBIC and GOME-2 retrievals

“…Since Bobrowski et al (2003) detected large amounts of BrO downwind of the Soufrière Hills volcano (Montserrat) measurements (and simulation studies) also target the chemistry of halogen compounds. A few years later volcanic BrO emissions were also studied using aircraft measurements (Bani et al, 2009) and satellite observations (Theys et al, 2009). Compared to ground based measurements both airborne and satellite observation offer the advantage that measurements at various distances from the crater can be performed with the same instrument.…”