Arctic Holocene Transitions
This project seeks to advance our understanding of centennial-scale variability in the Arctic system and the feedbacks that lead to pronounced changes. It focuses on the transition from the warmer early Holocene to the cooler late Holocene, and the shift in ocean-atmospheric circulation associated with this change in the mean state of climate (climate-system reorganization).
To advance this goal, this project will first assess the extent to which prominent climate/environmental shifts that are known from new and existing proxy climate records are contemporaneous within regions (climate driven), versus site-specific (catchment/proxy-specific threshold response). If regionally coherent, were they also synchronous across the Arctic, or does the spatial-temporal pattern resemble known dynamical modes of ocean-atmosphere circulation?
The current focus is on generating a coordinated series of summaries for six regions across the Arctic.
The leaders for the regions are:
Kaufman, Darrell (Alaska and Yukon)
Briner, Jason (Canadian Islands and Greenland)
Cwynar, Les (Mainland Canada)
Sejrup, Hans Petter (North Atlantic and Iceland)
Seppä, Heikki (European Arctic)
Solomina, Olga (Russian Arctic)
Darrell S. Kaufman, Professor
School of Earth Sciences & Environmental Sustainability
Northern Arizona University
Flagstaff, AZ 86011-4099
Arctic Holocene Proxy Climate Database
An extensive compilation of previously published Holocene proxy climate records from the Arctic. The article’s 21 authors identified 170 sites from north of 58° latitude where proxy records extend back at least 6000 years and meet other criteria for resolution and age control. They compiled the time series for each of the records, including metadata that capture the original author’s climate interpretation and the geochronological control. A “geochronology accuracy score” was developed to rate the overall reliability of radiocarbon-based age models from lake and marine sediments – the vast majority of the records.
The data product is now being used to investigate the spatio-temporal pattern of Arctic Holocene climate change and their causes.
Sundqvist HS, Kaufman DS, McKay NP, Balascio NL, Briner JP, Cwynar LC, Sejrup HP, Seppä H, Subetto DA, Andrews JT, Axford Y, Bakke J, Birks HJB, Brooks SJ, de Vernal A, Jennings AE, Ljungqvist FC, Rühland KM, Saenger C, Smol JP & Viau AE (2014) Arctic Holocene proxy climate database – New approaches to assessing geochronological accuracy and encoding climate variables, Climate of the Past 10(4): 1605-1631 doi:10.5194/cp-10-1605-2014