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High resolution DEMs obtained from LiDAR topographic data have led to improved landform inventories (e.g. landslides and fault scarps) and understanding of geomorphic event frequency. Here we use airborne LiDAR mapping to investigate meltwater pathways associated with the Tweed Valley palaeo ice-stream (UK). In particular we focus on a gorge downstream of Palaeolake Milfield, previously mapped as a sub-glacial meltwater channel, where the identification of abandoned headcut channels, run-up bars, rock-cut terrace surfaces and eddy flow features attest to formation by a sub-aerial glacial lake outburst flood (GLOF) caused by breaching of a sediment dam, likely an esker ridge. Mapping of these landforms combined with analysis of the gorge rim elevations and cross-section variability revealed a two phase event with another breach site downstream following flow blockage by higher elevation drumlin topography. We estimate the magnitude of peak flow to be 1–3 × 103 m3/s, duration of the event to range from 16–155 days, and a specific sediment yield of 107–109 m3/km2/yr. We identified other outburst pathways in the lower Tweed basin that help delineate an ice margin position of the retreating Tweed Valley ice stream. The results suggest that low magnitude outburst floods are under-represented in Quaternary geomorphological maps. We therefore recommend regional LiDAR mapping of meltwater pathways to identify other GLOFs in order to better quantify the pattern of freshwater and sediment fluxes from melting ice sheets to oceans. Despite the relatively low magnitude of the Till outburst event, it had a significant impact on the landscape development of the lower Tweed Valley through the creation of a new tributary pathway and triggering of rapid knickpoint retreat encouraging new regional models of post-glacial fluvial landscape response. Copyright © 2015 John Wiley & Sons, Ltd.

Research by Eugene Hunn (1996) suggested that toponymic density and population density are roughly equal for a range of indigenous groups across North America. In Wemindji, Quebec, historic and current toponymic and population data support Hunn's observation. I demonstrate that toponymic constraints are real by holding the number of traditional toponyms (898) as a background constant, and estimating the growth of Wemindji's population from 1960 to 2010 based on knowledge held by local experts. Measurements from historic air photographs assumed toponymic growth proportional to the area within the limits of Wemindji town development. A set of 78 new town place names provide a baseline for that measurement. Relative to toponymic density, population density steadily increased from 1960 to 2010, with a graph depicting the two densities suggesting equality in approximately 1995. Les contraintes toponymiques a Wemindji Les travaux de recherche realises par Eugene Hunn (1996) ont pu demontrer que la densite toponymique et la densite de la population chez divers groupes autochtones partout en Amerique du Nord sont sensiblement egales. Les observations faites par Hunn sont corroborees par les donnees relatives a la population et a la toponymie actuelles et historiques de Wemindji, Quebec. L'importance bien reelle des contraintes toponymiques est mise en evidence en considerant le nombre traditionnel de toponymes (898) comme une constante de fond et en se referant a une estimation de la croissance de la population de Wemindji entre 1960 et 2010 qui provient des connaissances detenues par des experts locaux. Des mesures effectuees a partir de photographies aeriennes historiques tenaient pour acquis que la croissance toponymique etait proportionnelle a la superficie du territoire urbanise de Wemindji. Les 78 nouveaux noms de lieux apparus dans le village fournissent une valeur de reference pour cette mesure. De concert avec la densite toponymique, la densite de la population n'a cesse de croitre entre1960 et 2010. Les deux densites sont presentees sous forme d'un graphique indiquant que l'egalite fut etablie vers 1995.

This commentary is a direct response to the Forum article ‘Environmentalist thinking and/in geography’ by Radcliffe et al. (2010) . Two main problems are addressed: the perpetuation of a false analogy between cultural and biological evolution, and a misunderstanding of memes. I review the literature and summarize the main issues in cultural and biological evolution and in the related field of memetics, noting ways in which the Forum’s authors’ arguments might be strengthened. In conclusion, some suggestions are made for how geographers might productively engage with innovative ideas from other closely related disciplines.

This short article reviews and critically appraises Kingsbury and Jones’ (2009) Geoforum article entitled “Walter Benjamin’s Dionysian Adventures on Google Earth”, and finds it lacking in several regards. First, the use of Nietzsche’s Dionysus/Apollo dichotomy is in fact a double binary, in which Apollonian logic is constructed as a binary within the dichotomy, while the Dionysian logic is ‘bacchanalian’. Second, Walter Benjamin as exemplar of Dionysian logic is shown to be problematic and more a distraction from the flawed Nietzschean logic than a useful construct in itself. Lastly, the educational potential of Google Earth is overlooked by Kingsbury and Jones, in their haste to see Google Earth through ‘Google goggles’, in which everything Google appears through Dionysian-tinted lenses.

The publication of volume six of The History of Cartography is a momentous occasion. Monmonier, its editor, has the right blend of general and specialist knowledge to make this a very special volum...