Lectures

Lectures in 2007-8

7:30 -9:30 pm on Thursdays in the Friends Meeting House, Upper Goat Lane, Norwich.  Good car parking facilities are available in the multi-storey next door. Come early (from 7:00) to join informal discussions and meet your fellow members.

October 18th    Prof Tony Stuart, “Late Quaternary megafaunal extinctions in Northern Eurasia”
We live today in a zoologically impoverished world from which most of the largest and most spectacular terrestrial vertebrates (megafauna) have disappeared in the recent geological past. Losses include mammoths (2 species), mastodons, sabretooths, ground sloths and many other species in North America, and woolly mammoth, woolly rhino, giant deer (‘Irish elk’), cave bear, cave lion, and spotted hyena in Northern Eurasia. South America and Australia were also severely affected. Did these Late Quaternary megafaunal extinctions result from climatic/vegetational changes, ‘overkill’ by human hunters, or a combination of both? Resolution of this crucial issue can only come from detailed research, especially constructing a firm chronology of extinctions in each region. 
In our current NERC funded research project we are generating new AMS radiocarbon dates made directly on material of to establish a reliable chronology for the extinct megafauna of Northern Eurasia ca. 45 to 5 thousand years BP. A major aspect of our project is comparing the megafaunal record with the archaeological and vegetational evidence using GIS mapping and range charts with the aim of better understanding the cause or causes of these extinctions.

November 15th  Dr Tim Lenton, UEA. “Tipping points in the Earth system”
The term “tipping point” usually refers to a critical threshold at which a tiny perturbation can qualitatively alter the state and development of a system. The term “tipping element” has been introduced to describe large-scale components of the Earth System that may pass a tipping point. Of particular interest are those elements in the climate system that may be tipped by human activities this century and undergo a qualitative change before the next millennium. We have critically reviewed these potential policy-relevant tipping elements, drawing on the fast-increasing pertinent literature and an international workshop, in order to compile a master list and assess where their tipping points lie. For an important subset, their sensitivity to global warming and the uncertainties in this are ranked using the results from an expert elicitation exercise. The Greenland Ice Sheet emerges as the tipping element with the nearest threshold and the least uncertainty in this. The majority of causal connections identified between tipping elements are ‘positive’ – where tipping one element encourages tipping another. This raises the alarming possibility of human activities triggering “domino dynamics” in the climate system. The implications for human societies and climate policy are profound. In principle, early warning systems could be established to detect the proximity of some tipping points, but in practice the necessary long time-series of high resolution observations are lacking. Recognizing the nonlinearity in damage costs associated with passing a tipping point fundamentally alters the minimisation problem for the combined costs of mitigation and adaptation, shifting temperature targets accordingly. On the other hand, the accessibility of certain tipping points in the socio-economic system may even provide no-regret options for triggering the transition to a low carbon economy.
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December  6th   Dr R Belshaw,  "Sedimentary and surface processes in the development of the East Anglian landscape". 
Sedimentary Processes.  River Processes-What flowing water can and cannot do; the importance of super-critical flow; why lowland rivers cannot incise and form terraces in warm periods; why they might incise in cold periods. Marine Processes-Sub-tidal channels; tidal barrier beaches; the effect of changes in sea-level
Landscape evolution in central and eastern England since the early Tertiary

January 10th  2008  Prof. Conway-Morris.  "Does evolution have a direction, and if so where is it going?"
Is evolution a random, open-ended process without inherent predictability?  "Re-run the tape of life", claimed Stephen J. Gould and the out-come will be entirely different: no humans, for example.  Prof. Conway-Morris will argue the exact reverse.  Evolution is far more predictable than generally thought, whether we are talking about molecules or societies.  This means human-like intelligence is very probable, perhaps inevitable.  So not only does this indicate a deep structure to evolution, but re-opens the question posed by Fermi: where are the extraterrestrials?

February 21st,  Dr Steven Pawley on the chronology of glaciations.
Steve will tell us of his research in North Norfolk and how he has unravelled the evidence of several glaciations to establish their chronology.