Ice core paleovolcanic records from the St. Elias Mountains, Yukon, Canada

Abstract

We previously reported a record of regionally significant volcanic eruptions in the North Pacific using an ice core from Eclipse Icefield (St. Elias Mountains, Yukon, Canada). The acquisition of two new ice cores from Eclipse Icefield, along with the previously available Eclipse Icefield and Mount Logan Northwest Col ice cores, allows us to extend our record of North Pacific volcanism to 550 years before present using a suite of four ice cores spanning an elevation range of 3–5 km. Comparison of volcanic sulfate flux records demonstrates that the results are highly reproducible, especially for the largest eruptions such as Katmai (A.D. 1912). Correlation of volcanic sulfate signals with historically documented eruptions indicates that at least one‐third of the eruptions recorded in St. Elias ice cores are from Alaskan and Kamchatkan volcanoes. Although there are several moderately large (volcanic explosivity index (VEI) ≥ 4) eruptions recorded in only one core from Eclipse Icefield, the use of multiple cores provides signals in at least one core from all known VEI ≥ 4 eruptions in Alaska and Kamchatka since A.D. 1829. Tephrochronological evidence from the Eclipse ice cores documents eruptions in Alaska (Westdahl, Redoubt, Trident, and Katmai), Kamchatka (Avachinsky, Kliuchevoskoi, and Ksudach), and Iceland (Hekla). Several unidentified tephra‐bearing horizons, with available geochemical evidence suggesting Alaskan and Kamchatkan sources, were also found. We present a reconstruction of annual volcanic sulfate loading for the North Pacific troposphere based on our ice core data, and we provide a detailed assessment of the atmospheric and climatic effects of the Katmai eruption.

Perchlorate Depositional History as Recorded in North American Ice Cores from the Eclipse Icefield, Canada, and the Upper Fremont Glacier, USA

“…Chronology of the Eclipse ice core is based on multi-parameter annual layer counting of seasonal oscillations in the stable isotope (δ 18 O) and major ion records (Na + ). The Eclipse ice core (core 3) covers the period 1910 to 2002, with dating error in the core estimated to be ±1 year based on the number of independently dated horizons (Yalcin et al 2007). The relatively higher resolution of the Eclipse ice core (average annual accumulation rate=1.30 m water equivalence (w.e.))…”

“…We analyzed subsamples from previously studied ice cores (Yalcin et al 2007(Yalcin et al , 2006aSchuster et al 2000Schuster et al , 2002 in the Upper Fremont Glacier (UFG) at the Wind River Range, Wyoming (43°07′ N, 109°37′ W; 4,100-m elevation) and the Eclipse Icefield, Yukon Territory, Canada (60.51°N, 139.47°W; 3,017-m elevation). The UFG samples were produced from ice cores (2 nos.)…”

“…drilled in 1991 and 1998, and the Eclipse core (core 3) was drilled in 2002. Details on the drilling of ice cores, recovery, and preservation are detailed elsewhere (Yalcin et al 2007(Yalcin et al , 2006aSchuster et al 2002). Ice core subsamples along with a travel blank were shipped in clean plastic bottles to Texas Tech University, Lubbock, Texas, and upon arrival were immediately transferred to laboratory freezers.…”

Records of volcanic events since AD 1800 in the East Rongbuk ice core from Mt. Qomolangma

“…More and more ice cores are available for studying volcanic events [12][13][14][15][16] , which provides a reliable method to understand the global historical volcanic eruptions. However, few ice cores from the low-latitude mountainous glaciers have been used for reconstructing the volcanic events due to the disturbance of high dust background.…”

The Role of Volcanic Activity in Climate and Global Change

“…A significant amount of volcanic aerosols penetrated to the troposphere through the tropopause folds is washed out in storm tracks. Aerosols deposited in downward branches of the Brewer-Dobson circulation in the polar regions are preserved in the polar ice sheets, recording the history of the Earth's explosive volcanism for thousands of years [24][25][26]. However, the atmospheric loadings calculated using volcanic time series from high-latitude ice records suffer from uncertainties in observation data and poor understanding of atmospheric transport and deposition processes.…”