Composition and evolution of volcanic aerosol from eruptions of Kasatochi, Sarychev and Eyjafjallajökull in 2008–2010 based on CARIBIC observations

Abstract

Large volcanic eruptions impact significantly on climate and lead to ozone depletion due to injection of particles and gases into the stratosphere where their residence times are long. In this the composition of volcanic aerosol is an important but inadequately studied factor. Samples of volcanically influenced aerosol were collected following the Kasatochi (Alaska), Sarychev (Russia) and also during the Eyjafjallajökull (Iceland) eruptions in the period 2008–2010. Sampling was conducted by the CARIBIC platform during regular flights at an altitude of 10–12 km as well as during dedicated flights through the volcanic clouds from the eruption of Eyjafjallajökull in spring 2010. Elemental concentrations of the collected aerosol were obtained by accelerator-based analysis. Aerosol from the Eyjafjallajökull volcanic clouds was identified by high concentrations of sulphur and elements pointing to crustal origin, and confirmed by trajectory analysis. Signatures of volcanic influence were also used to detect volcanic aerosol in stratospheric samples collected following the Sarychev and Kasatochi eruptions. In total it was possible to identify 17 relevant samples collected between 1 and more than 100 days following the eruptions studied. The volcanically influenced aerosol mainly consisted of ash, sulphate and included a carbonaceous component. Samples collected in the volcanic cloud from Eyjafjallajökull were dominated by the ash and sulphate component (∼45% each) while samples collected in the tropopause region and LMS mainly consisted of sulphate (50–77%) and carbon (21–43%). These fractions were increasing/decreasing with the age of the aerosol. Because of the long observation period, it was possible to analyze the evolution of the relationship between the ash and sulphate components of the volcanic aerosol. From this analysis the residence time (1/e) of sulphur dioxide in the studied volcanic cloud was estimated to be 45 ± 22 days

Global-scale atmosphere monitoring by in-service aircraft – current achievements and future prospects of the European Research Infrastructure IAGOS

“…Weigelt et al (2009) analysed several hundred cloud encounters in five geographic regions using IAGOS-CARIBIC data and showed that deep convective clouds in the tropics act as a particle source. Another important source for UTLS aerosols is volcanic eruptions (Andersson et al, 2013) with significant impacts on the radiation budget of the LS and on cirrus cloud coverage . Andersson et al (2013) also calculated the residence time (1/e) of SO 2 in two volcanic clouds to be about 45 d.…”

“…Another important source for UTLS aerosols is volcanic eruptions (Andersson et al, 2013) with significant impacts on the radiation budget of the LS and on cirrus cloud coverage . Andersson et al (2013) also calculated the residence time (1/e) of SO 2 in two volcanic clouds to be about 45 d.…”

Sub-micrometer refractory carbonaceous particles in the polar stratosphere

“…However, carbonaceous material was found in samples from the Kasatochi (Alaska, 2008), Sarychev (Russia, 2009) as well as Eyafjallajökull (Iceland, 2010) eruptions (Martinsson et al, 2009;Schmale et al, 2010;Andersson et al, 2013). The carbonaceous material most probably originates from air entrained into the volcanic cloud.…”

Nabro volcano aerosol in the stratosphere over Georgia, South Caucasus from ground-based spectrometry of twilight sky brightness

“…Jégou et al (2013) combined satellite-based limb and lidar measurements, ground-based lidar measurements and in situ balloon measurements to investigate Arctic region stratospheric aerosols from the Sarychev volcano eruption in the summer of 2009. Andersson et al (2013) investigated composition and evolution of volcanic aerosols from the eruptions of Kasatochi, Sarychev and Eyjafjallajökull in 2008-2010 based on CARIBIC (Civil Aircraft for Regular Investigation of the atmosphere Based on an Instrument Container) observations. Aerosol particles of 0.08-2 µm aerodynamic diameters were collected.…”