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The oxygen isotope signal in benthic foraminifera from deep-sea cores is mainly determined by deep-ocean temperature and land ice volume. Separating the temperature and ice volume signals is a key step in understanding the evolution of Cenozoic climate. Except for the last few million years, fluctuations in land ice volume were determined mainly by the size of the Antarctic ice sheet. Here a simplified Antarctic ice-sheet model and composite deep-sea oxygen isotope records are used to derive a deep-sea temperature history for the Cenozoic. The ice-sheet model is forced with the oxygen-isotope record, which is instantaneously corrected for the calculated ice volume. Therefore, the resulting deep-sea temperature and Antarctic ice volume curves are mutually consistent.The temperature record of Lear et al. [Science 287 (2000) 269], derived from the Mg/Ca ratio in benthic calcite, is also used to force the ice-sheet model. The resulting ice-volume does not agree well with the ice-volume history inferred by Lear et al. from a comparison of Mg/Ca and δ18O records.The most important points emerging from this study are: [Copyright &y& Elsevier]

Presents a study that investigated the data from several automatic weather stations concerning katabatic flow over glaciers. Background on the glacier winds; Information on the wind maximum and vertical temperature of glaciers; Discussion on the Prandtl model used in the estimation of heat flux associated with the glacier wind.

A letter to the editor is presented in response to various articles on the stability of the Antarctic and Greenland Ice Sheets in the March 24, 2006 issue.

Reports on a workshop held during the Climate Conference in August 2001 at Utrecht University in the Netherlands regarding the katabatic flows over glaciers and ice sheets. Effects of turbulence on the glacier surface and atmosphere; Reasons behind the existence of katabatic flows; Discussion on the spatial scale of glaciers.

Understanding the interactions between surface and deep Earth processes is important for research in many diverse scientific areas including climate, environment, energy, georesources and biosphere. The TOPO-EUROPE initiative of the International Lithosphere Program serves as a pan-European platform for integrated surface and deep Earth sciences, synergizing observational studies of the Earth structure and fluxes on all spatial and temporal scales with modelling of Earth processes. This review provides a survey of scientific developments in our quantitative understanding of coupled surface-deep Earth processes achieved through TOPO-EUROPE. The most notable innovations include (1) a process-based understanding of the connection of upper mantle dynamics and absolute plate motion frames; (2) integrated models for sediment source-to-sink dynamics, demonstrating the importance of mass transfer from mountains to basins and from basin to basin; (3) demonstration of the key role of polyphase evolution of sedimentary basins, the impact of pre-rift and pre-orogenic structures, and the evolution of subsequent lithosphere and landscape dynamics; (4) improved conceptual understanding of the temporal evolution from back-arc extension to tectonic inversion and onset of subduction; (5) models to explain the integrated strength of Europe's lithosphere; (6) concepts governing the interplay between thermal upper mantle processes and stress-induced intraplate deformation; (7) constraints on the record of vertical motions from high-resolution data sets obtained from geo-thermochronology for Europe's topographic evolution; (8) recognition and quantifications of the forcing by erosional and/or glacial-interglacial surface mass transfer on the regional magmatism, with major implications for our understanding of the carbon cycle on geological timescales and the emerging field of biogeodynamics; and (9) the transfer of insights obtained on the coupling of deep Earth and surface processes to the domain of geothermal energy exploration. Concerning the future research agenda of TOPO-EUROPE, we also discuss the rich potential for further advances, multidisciplinary research and community building across many scientific frontiers, including research on the biosphere, climate and energy. These will focus on obtaining a better insight into the initiation and evolution of subduction systems, the role of mantle plumes in continental rifting and (super)continent break-up, and the deformation and tectonic reactivation of cratons; the interaction between geodynamic, surface and climate processes, such as interactions between glaciation, sea level change and deep Earth processes; the sensitivity, tipping points, and spatio-temporal evolution of the interactions between climate and tectonics as well as the role of rock melting and outgassing in affecting such interactions; the emerging field of biogeodynamics, that is the impact of coupled deep Earth – surface processes on the evolution of life on Earth; and tightening the connection between societal challenges regarding renewable georesources, climate change, natural geohazards, and novel process-understanding of the Earth system. • Coupled surface-deep Earth processes determine Earth evolution and environment. • An adequate response to societal geo-challenges requires Earth System Science. • Earth System Science allows tackling frontier research and innovative applications. • TOPO-EUROPE is a robust platform to assess natural hazards and geo-resources. [ABSTRACT FROM AUTHOR]

The Antarctic Vostok ice core provided compelling evidence of the nature of climate, and of climate feedbacks, over the past 420,000 years. Marine records suggest that the amplitude of climate variability was smaller before that time, but such records are often poorly resolved. Moreover, it is not possible to infer the abundance of greenhouse gases in the atmosphere from marine records. Here we report the recovery of a deep ice core from Dome C, Antarctica, that provides a climate record for the past 740,000 years. For the four most recent glacial cycles, the data agree well with the record from Vostok. The earlier period, between 740,000 and 430,000 years ago, was characterized by less pronounced warmth in interglacial periods in Antarctica, but a higher proportion of each cycle was spent in the warm mode. The transition from glacial to interglacial conditions about 430,000 years ago (Termination V) resembles the transition into the present interglacial period in terms of the magnitude of change in temperatures and greenhouse gases, but there are significant differences in the patterns of change. The interglacial stage following Termination V was exceptionally long--28,000 years compared to, for example, the 12,000 years recorded so far in the present interglacial period. Given the similarities between this earlier warm period and today, our results may imply that without human intervention, a climate similar to the present one would extend well into the future.