Multiproxy records of anthropogenic and climate change in Ireland over the last 1, 200 years.
by
Edwina Cole
Department of Botany, Trinity College, Dublin 2, Ireland.
Coauthors: Fraser Mitchell (Department of Botany, Trinity College, Dublin 2, Ireland)

In order to understand recent and future climate change, it is necessary to document how climates have varied in the past. Ireland has a wealth of Late-glacial and Holocene palynology records which provide data on past climates and their associated impacts. Unfortunately most lack the temporal resolution necessary to investigate small climatic changes on centennial to millennial scales (such as the Medieval Warm Period, the Little Ice Age and 20th Century Warming) and to provide information on these and the environmental changes that may have occurred as a result of these climatic changes.

Various methods including pollen analysis, fungal spore and testate amoebae analysis, charcoal analysis, loss on ignition and dating in the form of radiocarbon dating and tephrochronology were employed to construct a high resolution multiproxy record of climate and its environmental impact over the last 1,200 years from three sites in an east to west transect across Ireland.

The regional pollen record charts anthropogenic impact on the landscape which appears to mask impacts caused directly by climate change. Evidence from local pollen and fungal spores suggest that between AD 1150 and AD 1300 Ireland in general experienced mainly wet conditions whereas between 1550 and 1700 dry conditions are suggested by the data. Increasing dry conditions are illustrated in some ways in records from each of the three sites during the time of 20th Century Warming. These dry conditions (as suggested by either local pollen or fungal spore data) during this time period may be due to anthropogenic impacts also such as drainage and peat cutting but climate is also thought to play a role in causing this dryness. The sensitivity to climate appears to be more pronounced in the most western site. This may be due to a combination of its remoteness and its proximity to the Atlantic ocean.

The multiproxy approach has resulted in a detailed, well dated palaeoecological record of the last 1,200 years in three sites across Ireland. Details of climate however are more difficult to interpret and from this study different proxies appear to contradict others with respect to similar time periods in the cores. This may be due to the large anthropogenic impact on the landscape over the last 1,200 years. Another source of error may be the limited number of fungal spore taxa used to infer bog surface wetness.

Date received: March 27, 2001

Copyright © 2001 by the author(s). The author(s) of this document and the organizers of the conference have granted their consent to include this abstract in Atlas Conferences Inc. Document # cagc-36.