Cookies

We use cookies to ensure that we give you the best experience on our website. By continuing to browse this repository, you give consent for essential cookies to be used. You can read more about our Privacy and Cookie Policy.


Durham Research Online
You are in:

Testing lichenometric techniques in the production of a new growth-rate (curve) for the Breidamerkurjokull foreland, Iceland, and the analysis of potential climatic drivers of glacier recession.

Evans, D.J.A. and Gudmundsson, S. and Vautrey, J.L. and Fernyough, K. and Southworth, W.G. (2019) 'Testing lichenometric techniques in the production of a new growth-rate (curve) for the Breidamerkurjokull foreland, Iceland, and the analysis of potential climatic drivers of glacier recession.', Geografiska annaler, series A, physical geography., 101 (3). pp. 225-248.

Abstract

Independent dating of closely-spaced moraines on the west Breiðamerkurjökull foreland is used to test the accuracy of the size frequency (SF) and largest lichen (5LL) lichenometric dating techniques. The 5LL technique derived the most accurate ages for three undated moraines within the dated sequence but growth rates and lag times produced by the two methods (5LL = 0.71 mm yr-1 and 11 years; SF = 0.64 mm yr-1 and 7 years) were not significantly different. We therefore reject previous conclusions that any one technique is demonstrably inferior to the other, at least for dating glacial landforms created over the last 130 years in SE Iceland. Comparisons of climate trends and recession rates indicate that air temperature anomalies, particularly those of the summer, are the strongest driver of glacier retreat. No clear relationship between NAO trends and glacier retreat were identified, although a positive and/or rising trend in NAO is associated with the slowing of ice retreat overall, and the marked readvances of the mid-1950s, mid-1970s and mid-1990s are all coincident with positive and/or rising NAO 5yr moving averages. Summer and annual temperature trends, not the NAO, clearly show that recent accelerated global warming is driving the marked recession of the period 1995-2015. Over the last 100 years temperature has been the major driver of glacier terminus oscillations at west Breiðamerkurjökull but it is clear that extreme decreases in winter precipitation (i.e. 1960-73) have the potential to increase retreat rates significantly even during times of below average annual temperatures.

Item Type:Article
Full text:(AM) Accepted Manuscript
Download PDF
(2589Kb)
Status:Peer-reviewed
Publisher Web site:https://doi.org/10.1080/04353676.2019.1622919
Publisher statement:This is an Accepted Manuscript of an article published by Taylor & Francis in Geografiska Annaler on 30 June 2019, available online: http://www.tandfonline.com/10.1080/04353676.2019.1622919
Date accepted:29 April 2019
Date deposited:13 June 2019
Date of first online publication:30 June 2019
Date first made open access:30 June 2020

Save or Share this output

Export:
Export
Look up in GoogleScholar