During the Cretaceous, planktonic Foraminiferida underwent a major diversification, colonizing a wider range of water depths and geographical regions. Orville Bandy, over 30 years ago, was the first to recognize the potential of using this regional distribution to reconstruct different palaeoceanographic regimes. Using new data from the South Atlantic Ocean, Antarctic Ocean and the Indian Ocean it is possible to show the poleward migration of warm-water taxa during the Cretaceous and compare it with data already available from the Northern Hemisphere. Instead of the present-day nine latitudinal zones based on planktonic taxa it is only possible to identify five with any degree of reliability. These are from north to south, the Boreal, Transition, Tropical (= Tethyan), Transition and Austral. In some of the developing oceans during the Cretaceous (e.g. the Eastern Indian Ocean, South Atlantic Ocean) there are local biogeoprovinces with quite distinctive local assemblages and morphotypes. While these do not reflect on the climatic zonation they provide an interesting insight into the development of the plankton. The foraminiferal distributions are compared with climatic maps produced by the assessment of other data sources.
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Climates: Past and Present
The climate of the early Earth was probably very warm and has, in general, reduced since the Archean. However, it now seems that the world is about 0.6°C warmer than it was 100 years ago and estimates of the rate of global warming over the next century range from 0.16°C to 0.35°C per decade. Concurrently, global sea-level is predicted to rise from 2.4 to 10 cm per decade. These rates of change are much faster than those normally associated with the geological record, causing geologists and palaeontologists to reassess their data and their forecasts on rates of future change.
With the current interest in global climatic change and, more specifically, with global warming, it is clear that palaeontologists have valuable information to provide on the impacts of past climatic change. This volume contains papers from an international array of such geologists and palaeontologists, showing how studies of micro- and macrofossils, plant and vertebrate fossils from a range of geological ages have contributed to our understanding of how climate affects both local and more widespread areas. The contributions are arranged in geological order, ranging from the Permo-Carboniferous to the post-glacial recovery of the last 18,000 years, with an emphasis on climate change during the last two million years, particularly in NW Europe.
Climates: Past and Present will be of interest to palaeontologists, geologists and palaeoclimatologists who specialize in climatic reconstructions and any professionals enagaged in research into the geological aspects of climate change.