Midge-inferred temperatures from Iceland lakes

Midge-inferred temperatures from Iceland lakes: Defining an Icelandic response to abrupt climate change and climate periodicity in the North Atlantic
Collaborators: Yarrow Axford (http://ucsub.colorado.edu/~axford/) — Searching for the Icelandic signature of abrupt change in the North Atlantic, Gifford H. Miller (http://instaar.colorado.edu/people/bios/miller.html), Peter G. Langdon (http://gg-svr7.geog.soton.ac.uk/staff/pgl/profile/default.aspx)

In this project, which started in 2007 we propose to reconstruct summer air temperatures over Iceland through the Holocene at ~100-yr resolution, using changes in chironomid assemblages preserved in lake sediments. Our research focusses on abrupt temperature changes and climate periodicities. Temperature inferences will utilize an existing Icelandic chironomid-temperature transfer function, which will be improved with additional calibration data as part of this research.

The research will:
Expand the modern calibration data set for chironomid-based temperature inferences on Iceland, approximately doubling the number of calibration sites. The lake downcore effort proposed, as well as other ongoing and future work, will benefit from an improved chironomid-temperature transfer function.

Generate high-resolution Holocene temperature reconstructions. This will be the first study aimed at quantifying abrupt Holocene climate changes on Iceland, and the first aimed at constraining temperature changes associated with millennial-scale climate periodicity.

Monitor subtle environmental changes through the Holocene using high-resolution BiSiO2 and TOC measurements. These proven sensitive indicators of environmental change will be measured at sub-centennial resolution, providing a qualitative record of centennial- and millennial-scale climate variations.

Yarrow Axford´s postdoctoral research and the cost of field work in Iceland was supported by the Gary S. Comer Educational and Research Foundation and a postdoctoral grant from the University of Iceland.