Eruption dynamics of the 22–23 April 2015 Calbuco Volcano (Southern Chile): Analyses of tephra fall deposits

Abstract

26After 54 years since its last major eruption in 1961, Calbuco volcano (Ensenada, 27 Southern Chile) reawakened with few hours of warning on 22 April 2015 at 18:05 local

Direct injection of water vapor into the stratosphere by volcanic eruptions

“…The back trajectories from the geolocations of the MLS‐observed enhancements at 83 and 68 mb originate very close to Calbuco at the time of the first eruption event at ~21:00 on 22 April 2015 [ Romero et al , ], with altitudes of 16.6 and 15.7 km, respectively (Figure ). The tropopause pressure in the NCEP product at the nearest point in space to Calbuco linearly interpolated to the time of the first eruptive event (42.5°S, 72.5°W at 21:00 UTC on 22 April) is 167 mb, which corresponds to a significantly lower height than the plume at that time, indicating that volcanic water vapor was directly injected into the stratosphere in all likelihood.…”

“…The Chilean volcano Calbuco (41.326°S, 72.614°W) erupted on 22 and 23 April 2015, with the eruption column reaching ≥15 km during both events [ Romero et al , ]. This eruption has a VEI of 4 [ Van Eaton et al , ].…”

Comparisons of the Orbiting Carbon Observatory-2 (OCO-2) <i>X</i><sub>CO<sub>2</sub></sub> measurements with TCCON

“…The Southern Hemisphere ocean glint bias does not impact the overall scaling bias between OCO-2 and TCCON X CO 2 within the uncertainty but does impact the latitudinal gradients (and hence fluxes) inferred by the OCO-2 data. While the cause of the bias in the southern winter is currently unclear, there is a promising hypothesis related to the OCO-2 B7r algorithm's misrepresentation of stratospheric aerosols, exacerbated by the eruption of Mount Calbuco in Chile on 22 April 2015 (Romero et al, 2016). The overall comparisons between the OCO-2 data and TCCON data are reported in Tables 3 and 5 and shown in Figs.…”

Tephra From the 3 March 2015 Sustained Column Related to Explosive Lava Fountain Activity at Volcán Villarrica (Chile)

“…At farther distances (>40 km), only individual fine lapilli (2-5 mm) particles were found without the formation of a homogeneous tephra layer ( Figure 4H). In those deposits, lapilli were partially cemented by the subsequent ash fallout from the eruption of Calbuco Volcano on 22-23 April 2015, which deposited a few mm of tephra in the area near to the international road (CH-199) and Mamuil-Malal mountain pass (see Romero et al, 2016b for details). Ash deposits were not detected at San Martín de Los Andes or Junin de los Andes in Argentina (Clarin, 2015).…”