Climate and surging of Donjek Glacier, Yukon, Canada

ABSTRACT

Links between climate and glacier surges are poorly understood but are required to enable prediction of surges and mitigation of associated hazards. Here, we investigate the role of snow accumulation, rain, and temperature on surge periodicity, area changes, and timing of surge initiation since the 1930s at Donjek Glacier, Yukon, Canada. Snow accumulation measured in three ice cores collected at Eclipse Icefield indicates that a cumulative accumulation of 15.5 ± 1.46 or 16.6 ± 2.0 m w.e. occurred in the ten to twelve years between each of its last eight surges, depending on ice motion spatiotemporal offset corrections. Although we find consistent snow accumulation between surges, the transient snow line has risen 10.3 m decade⁻¹ vertically since the 1950s, and Burwash Landing weather station records indicate a 0.5°C decade⁻¹ increase in mean annual air temperature since the 1960s. Changes in surface mass balance are accompanied by a consistent surge interval but decreasing surge extent. The three recent surge events initiated in years with the rainiest summers on record. These findings highlight a complex interplay between external (i.e., climate) and internal glacier processes that control surging at Donjek Glacier, with climate having a more direct influence on surge extent than on recurrence interval.

KEYWORDS:

• Glacier surge
• climate
• ice cores
• Donjek Glacier
• Yukon

Acknowledgments

This work was undertaken in the Traditional Territory of the Kluane First Nation people, and we are thankful for their engagement with this work. We thank Daniel Dixon, Steven Bernsen, Justin Leavitt (University of Maine), Dorota Medrzycka (University of Ottawa), and Patrick Saylor (Dartmouth College) for their help collecting the 2016 ice core, Douglas Introne and Michael Handley for ice core analysis, and Cameron Wake (University of New Hampshire) for help reprocessing the 2002 core isotope data. We thank Robert McNabb (University of Oslo) for the 2002 ASTER DEM and Icefield Discovery, Trans North helicopters, and the Kluane Lake Research Station for their logistical support. We thank the RemoteEx partnership exchange program, funded by the Norwegian Agency for International Cooperation and Quality Enhancement in Higher Education, for facilitating research collaboration that greatly benefited this work. Finally, we thank two anonymous reviewers and the Associate Editor Jacob Yde for their helpful comments in improving this manuscript.

Disclosure statement

No potential conflict of interest was reported by the authors.

Author Contribution

WK, KK, LC, and HJ designed the study. WK carried out data analysis for all remote sensing and weather station data. DW, EM, KK, WK, and SC collected and analyzed the 2016 ice core. DW, EM, KK, and WK reprocessed the 2002 ice core. SW provided analysis of the downscaled NARR data set. WK prepared the article with contributions from all co-authors.

Additional information

Funding

WK was supported by the National Science Foundation Graduate Research Fellowship under Grant No. DGE-1144205 and the Natural Sciences and Engineering Research Council of Canada Vanier Graduate Scholarship (201810CGV-416410-66257). WK thanks Dan and Betty Churchill for funding the 2017 field season and Geophysical Survey Systems, Inc., for funding the 2018 field season. LC thanks the Natural Sciences and Engineering Research Council of Canada, University of Ottawa, and Polar Continental Shelf Program for funding and field logistics. KK thanks the NSF for funding St. Elias research, NSF AGS-1502783. WorldView DEMs were provided by the Polar Geospatial Center under NSF-OPP awards 1043681, 1559691, and 1542736.