ARCUS | Arctic Research Consortium of the United States

7th Annual ARCUS Award for Arctic Research Excellence


Submitted by   Kaplan Yalcin
Authors  
Category   Interdisciplinary Research
Title   The 1907 Ksudach, Kamchatka and 1912 Katmai, Alaska Eruptions as Recorded in the Eclipse Ice Core, Yukon Territory
Affiliation   Climate Change Research Center, University of New Hampshire, Durham, NH, USA

Abstract

Analysis of major oxide composition of tephra associated with volcanic sulfate horizons in the Eclipse ice core via automated scanning electron microscope has identified tephra from the 1907 Ksudach, Kamchatka, and 1912 Katmai, Alaska eruptions, confirming my identification of these events in the Eclipse SO42- record and permitting detailed assessment of the associated atmospheric and environmental effects of these regionally significant eruptions. The Eclipse ice core suggests that the Katmai eruption plume consisted of both tropospheric and stratospheric components with different residence times and atmospheric effects. Atmospheric sulfate loading due to the Ksudach and Katmai eruptions is estimated from the Eclipse ice core using a multiplier relating the total atmospheric sulfate loading of the 1989-90 Redoubt eruption to the amount of volcanic sulfate deposited at Eclipse from that eruption. This technique derives minimum estimates for aerosol loading from Alaskan and Kamchatkan eruptions when compared to the techniques of other investigators but is not applicable to more distant eruptions due to greater uncertainty in relating ice core fluxes to atmospheric loading. The climatic significance of these eruptions in the Gulf of Alaska region is assessed using both the Eclipse oxygen isotope record as a temperature proxy and available instrumental temperature records from Alaska, the Yukon, and northern British Columbia. Instrumental temperature records suggest a two-year cooling following the Katmai eruption. I do not find compelling evidence for any climatic effect from the Ksudach eruption.