ARCSS Program | Co-oP Concept Paper Submissions By Author

Gifford Miller

Response: Volcanoes in the Arctic System

Response: Climate, Volcanoes, Climate change

Response: Lead: Gifford H. Miller
University of Colorado

Additional participants

University of Bergen, Norway
Hans Petter Sejrup
Haflidi Haflidason
Post-Doc (TBA)

University of Iceland
Aslaug Geirsdottir
Thor Thordarson
Sigfus Johnsen
Gudrun Johannsdottir (PhD Student)

University of Colorado, Boulder USA
Gifford Miller
Scott Lehman
John Andrews
Anne Jennings

NCAR
Bette Otto-Bliesner
Caspar Ammann

University of Massachusetts, Amherst USA
Ray Bradley
Julie Brigham-Grette

Queen's University, Belfast, Ireland
Jon Pilcher
Valerie Hall

Response: Two major centers of frequent explosive volcanism are found in the Arctic; along the subduction zone of the Aleutian trench and the Iceland hot spot. Both regions leave widespread, often geochemically diagnostic tephra across much of the Arctic. Explosive volcanism impacts Arctic climate and biota; the extensive tephra may allow synchronization of paleoclimate archives (ice cores, and lake and marine sediment). Precise synchronization provides one of the few tools to evaluate leads and lags between different components of the climate system. Explosive volcanism in the Arctic was more frequent in the early Holocene than in the last millennium, but the potential climate impacts have not been evaluated.
We propose a Community of Practice to focus on the impacts of volcanism on the Arctic system, and to better utilize the time synchronization offered by diagnostic tephra from both Alaskan and Icelandic sources.

Atmospheric component: How did frequent early Holocene explosive volcanism in the North Atlantic impact the climate system? Can diagnostic tephra in key paleoclimate archives be used to synchronize these records so that the leads and lags between ocean, atmosphere and solar forcing can be evaluated?

Limnological component: Does dusting lakes with tephra effect of nutrient loading and lead to a biotic response? Laminated sediment may allow a precise evaluation of these effects.

Geomorphology and fire-history component: Is there a link between eruptions and fires or changes in watershed and lake-sedimentation processes.

Marine circulation component: Can diagnostic tephras in marine sediment be used to evaluate the 14C reservoir age of surface waters through the Holocene for the high-northern latitudes? The spatial/temporal pattern of reservoir age provides first-order information on past changes in ocean circulation.

Response: The largest variable on decadal to centennial timescales that impacts Arctic climate is the transport of heat and moisture from lower latitudes by the ocean-atmosphere system via the Nordic Seas. This system accounts for approximately one-third of the heat in the Arctic, and is known to vary in response to changes in the AO (frequencies 10-15 years). Holocene paleorecords document strong power also at 80 and 200 years, frequencies known to characterize variations in solar luminosity. High-resolution records (100 to 101 yr) for the past 500 to 7000 years are available from ice cores, tree rings, and select marine and lacustrine sedimentary archives. Considerable success in combining these records for the past 500 years has allowed a reconstructing of changing modes of AO variability, also with suggestions of low-frequency (80 to 200 yr) cyclicities. However, the records are not long enough to confirm these cycles.

We envision an international effort that focuses on refining of the Arctic/Icelandic/Northern Hemisphere tephra chronology and testing of its utility in marine, terrestrial and ice core archives from around the Atlantic Arctic. The team will focus on the impacts of volcanism on the Arctic system utilizing climate models, and to better utilize the time synchronization offered by diagnostic tephra from both Alaskan/Cascade and Icelandic sources to evaluate leads and lags in the climate system. In keeping with ARCSS Program Goals, this effort is strongly international with other Arctic-rim countries around the North Atlantic. Although our initial list of CoP participants is biased toward the North Atlantic regions, we envision a stronger contribution from the Pacific sector as the project develops.

Response: Climate modeling groups, ice-core researchers, volcanologists

Response: Less than 30, more than 10

Response: Less than 30, more than 10

Response: Global modeling community, possibly the HARC community

Response: Web Conferences
Online Bulletin Board
Electronic email list

Response: What are you offering?