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Abstract
Caseldine, C., Stötter, J. and Wastl, M. (1998). Palaeoclimatic reconstruction in Northern Iceland: calibration and Holocene implications. 28th International Arctic Workshop, Arctic and Alpine Environments, Past and Present, Program with Abstracts, 1998. Institute of Arctic and Alpine Research, University of Colorado at Boulder, Boulder, 33.


The period since the mid 19th century, when instrumental meteorological recording first started in Iceland, has shown climate conditions close to, or possibly at, both Holocene minimum and optimum levels. The 19th century part of the Little Ice Age represents a thermal minimum, whilst the warmest decades of the 20th century are close to the estimated Holocene thermal maximum. A model describing sea-ice - climate - ELA relationships in Northern Iceland for this period is presented, which provides a calibrated proxy climate record as a basis for palaeoclimatic reconstruction for the Holocene as a whole.
Post-Preboreal Holocene climatic minima are marked by glacier advances to limits slightly in advance of those of the Little Ice Age. These have been dated so far to around 4700 BP, shortly after 4200 BP, between 3400 and 2800 BP, between 2200 and 1800 BP, around 1600 BP and around 1000 BP, based on radiocarbon dating and tephrochronology (Stötter et al., in press). At these times climatic conditions would have been comparable to the extremes of the 19th century. If it is assumed that annual mean temperatures experienced during the 1930s, the warmest in the observed record, are comparable to the Holocene thermal optimum, a range of ca 3K can be estimated for the Holocene as a whole. Studies of variations in the ELAs of glaciers in the Tröllaskagi area of Northern Iceland over the period of meteorological observations show a mean ELA rise of only 50m, over 200m less than that calculated from the observed temperature change of 1.7K in mean summer temperature. It is argued that this reflects a doubling of precipitation levels (Caseldine and Stötter, 1993).
This calibration provides a baseline for the examination of other proxy palaeoclimatic data for the Holocene as a whole, especially pollen and macrofossil evidence, the results of which are presented elsewhere.

References
Caseldine, C. and Stötter, J. (1993). 'Little Ice Age' glaciation of Tröllaskagi peninsula, northern Iceland: climatic implications for reconstructed equilibrium line altitudes (ELAs). The Holocene, 3(4), 357-366.
Stötter, J., Wastl, M., Caseldine, C. and Häberle, T. (in press). Holocene palaeoclimatic reconstruction in Northern Iceland: approaches and results. Quaternary Science Reviews.
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