SS3.09 Climate-Lake Interactions
Date: Wednesday, June 12, 2002
Time: 10:00:00 AM
Location: Colwood
 
MonteithDT, Environmental Change Research Centre, University College London, London, United Kingdom, dmonteit@geog.ucl.ac.uk
 
SENSITIVITY OF DIATOM COMMUNITY COMPOSITION IN UPLAND SCOTTISH LOCHS TO THE NORTH ATLANTIC OSCILLATION THROUGH INTER-ANNUAL VARIATION IN SPRING PRECIPITATION.
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Quarterly water chemistry and diatom species composition of annually retrieved sediment trap samples have been monitored in a set of upland acid-sensitive lakes in the UK since 1988. Lake pH is strongly dependent on the amount of recent precipitation, and the antecedent period which maximises this correlation is related to mean residence time. For lochs in northern Scotland, where anthropogenic acidification has been negligible, sediment trap diatom inferred pH is tightly anti-correlated with the mean amount of antecedent rainfall (period determined by relationship identified above) during 20 days in mid-spring. It is proposed that the sedimentary diatom record of lochs with a range of residence times might provide information on differing periods of spring precipitation. As precipitation in this region is tightly governed by the North Atlantic Oscillation, these findings have great potential for the reconstruction of spring climate at a regional scale.