"It is becoming increasingly recognized that sea level change since the LGM exhibits a globally complex spatial pattern : that sea level does not go up or down everywhere at the same rates, and may even differ in sign ; that sea levels did not first reach present values everywhere at the same time ; and that there is no simple relation between this sea level change and ice volumes. It is also widely accepted that this variability is the result of the earth-ocean response to the changing ice loads. But if this is so, why are these same messages largely forgotten in many discussions of sea level for earlier periods ? Why is it usually assumed that Last Interglacial shorelines - irrespective of whether these sites are at continental edges, mid-ocean islands or relatively near former ice margins – should occur at 4-8 m I the absence of vertical tectonic movements ? Why are LIg data from different localities combined without recognition that this may produce artificial oscillations in the resulting sea-level function ?
This seminar examines this issue with particular reference to two periods, the last Interglacial and the Late Pliocene and presents inferences on ice volumes during these periods and on tectonics."
Géophysicien, géodésien et planétologue australien de réputation mondiale, Kurt Lambeck enseigne à l'Australian National University (Australie). Ses recherches portent sur les variations de la rotation de la Terre, les déformations lentes de la Terre et l'élévation du niveau des mers à la suite des déglaciations.Cliquer ICI pour fermer
Dernière mise à jour : 14/02/2013