A series of ice-sheet-model intercomparison exercises have been organized as part of EISMINT. One such set of experiments investigated the implications of thermomechanical coupling on the flow of ice sheets with idealized geometry The results of these experiments are discussed by Payne and others (in press). They indicate that local concentrations of ice flow may develop as a consequence of interactions between ice flow, temperature and viscosity The nature of the intercomparison exercise meant that only a limited number of experiments could be performed by the ten contributing groups. Many of the implications arising from the results could not therefore be investigated. This paper focuses on four. They are the initiation of the patterning, its reversibility the influence of the relationship between ice temperature and viscosity and dependence on numerical time-step and horizontal grid size.

ABSTRACT. This work attempts to explain the fan-like landform assemblages observed in satellite images of the area covered by the former Scandinavian ice sheet (SIS). These assemblages have been interpreted as evidence of large ice streams within the SIS. If this interpretation is correct, then it calls into doubt current theories on the formation of ice streams. These theories regard soft sediment and topographic troughs as being the key determinants of ice-stream location. Neither can be used to explain the existence of ice streams on the flat, hard-rock area of the Baltic Shield. Initial results from a three-dimensional, thermomechanical ice-sheet model indicate that interactions between ice flow, form and temperature can create patterns similar to those mentioned above. The model uses a realistic, 20 km resolution gridded topography and a simple parameterization of accumulation and ablation. It produces patterns of maximum ice-sheet extent, which are similar to those reconstructed from the area's glacial geomorphology. Flow in the maximum, equilibrium ice sheet is dominated by wedges of warm, low-viscosity, fast-flowing ice. These are separated by areas of cold, slow-flowing ice. This patterning appears to develop spontaneously as the modelled ice sheet grows.

A new digital elevation model of the surface of the Greenland ice sheet and surrounding rock outcrops has been produced from a comprehensive suite of satellite and airborne remote-sensing and cartographic datasets. The surface model has been regridded to a resolution of 5 km, and combined with a new ice-thickness grid derived from ice-penetrating radar data collected in the 1970s and 1990s. A further dataset, the International Bathymetric Chart of the Arctic Ocean, was used to extend the bed elevations to include the continental shelf. The new bed topography was compared with a previous version used for ice-sheet modelling. Near the margins of the ice sheet and, in particular, in the vicinity of small-scale features associated with outlet glaciers and rapid ice motion, significant differences were noted. This was highlighted by a detailed comparison of the bed topography around the northeast Greenland ice stream.

Panic disorder is a common condition. Epidemiological studies throughout the world consistently indicate that the lifetime prevalence of panic disorder (with or without agoraphobia) is between 1.5% and 3.5%. Panic disorder shows substantial comorbidity with other forms of mental illness. Major depressive disorder occurs in 50 to 65% of individuals with panic disorder and there is considerable cross-sectional and longitudinal comorbidity with recurrent brief depression and dysthymia. Phobic anxiety disorders, most notably social phobia and generalised anxiety disorder, commonly occur with panic disorder, especially in individuals with more severe agoraphobia. Approximately 35 to 50% of individuals with panic disorder in community settings also have agoraphobia. Panic disorder also shows significant comorbidity with physical illness. Compared with individuals without or with some other psychiatric diagnosis, patients with panic disorder have an increased risk of suffering from multiple medically unexplained symptoms and are associated with high use of medical services and increased mortality from both cardiovascular and cerebrovascular disease.

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