Lichenometric dating of little ice age glacier activity in the central british columbia coast mountains, canada

Abstract

Abstract

The ittle ce ge behaviour of glaciers in the central ritish olumbia oast ountains, anada, was described by conducting lichenometric surveys of hizocarpon spp. found on recently deposited moraines in the itimat and acific ranges. At attullo lacier in the southern itimat ange, surveys across four sets of nested lateral moraines describe advances prior to the late thirteenth century, 1550–1610, 1680–1710, and 1850 ad. In the onarch cefield area in the northern acific ange, ittle ce ge moraines stabilized prior to 1380–1430 ad, the mid‐seventeenth and mid‐eighteenth centuries, and in the mid‐nineteenth century. The timing of these moraine‐building episodes corresponds closely to the intervals of glacier expansion recorded in complementary studies in the region. These findings indicate that most glaciers in the region reached their maximum downvalley ittle ce ge extent prior to 1780 ad, and suggest that climate forcing likely contributed to regionally synchronous glacier fluctuations.

Key words:

• lichenometry
• Rhizocarpon
• Little Ice Age

Acknowledgements

The authors thank Sandy Allen, Jodi Axelson, Jessica Craig, Laurel George, Alexis Johnson, Sarah Laxton, Mel Page, Kara Pitman, and Colette Starheim for their field assistance. Support for this research was provided by a Natural Science and Engineering Research Council of Canada (NSERC) award to Smith, and a Canadian Foundation for Climate and Atmospheric Science (CFCAS) award to the Western Canadian Cryospheric Network (WC²N). Permission to collect samples in North Tweedsmuir Provincial Park was granted by BC Parks.