Geoscience Reference
In-Depth Information
Chapter 4
Palaeometeorology
Abstract Review of Harmer's pioneer palaeometeorological research based on
the reconstruction of past circulation patterns including reference to climatic
changes during the Tertiary and Quaternary periods; formation of the East Anglian
Crag deposits; differences in meteorological conditions during the Pliocene epoch
compared with today; blocking anticyclones; travelling depressions; changes in
storm tracks; variations in the prevailing winds over East Anglia and southern
North Sea; comparison of charts by Harmer and Lamb for winter and summer
seasons during the Ice Age; possible changes in the distribution of land and sea;
comparison of past and present temperature gradients; increased storminess and
rainfall during the Pleistocene in the Mediterranean region.
Keywords Palaeometeorology
Tertiary and Quaternary periods
Past circula-
tion patterns
Synoptic analysis
Formation of the East Anglian Crag
Mol-
luscan fauna
Anticyclones
Depressions
North Atlantic Drift
4.1 Introduction
The distribution of the earth's landmasses and oceans into a geographical pattern
that would allow the development of climatic refrigeration occurred in the Tertiary
period and progressive cooling, which eventually led to the Pleistocene glacia-
tions, set in during the middle and late Miocene epoch; by the Pliocene epoch a
cool temperate climate prevailed in the British Isles. Major changes in the oceanic
circulation of the North Atlantic and the northward drift of the European landmass
were two further effects that contributed to the progressive cooling in that region.
Through his studies of the Tertiary and Quaternary periods Harmer became
interested in palaeometeorology and pioneered the reconstruction of past circu-
lation patterns, a valuable tool in meteorological analysis providing a synoptic or
'bird's eye' view of atmospheric behaviour. He was convinced that the major
changes of climate that occurred during the Pliocene and Pleistocene epochs were
