The risks to human populations in coastal areas are changing due to climate and socio-economic changes, and these trends are predicted to accelerate during the 21 st Century. To understand these changing risks, and the resulting choices and pathways to successful management and adaptation, broad-scale integrated assessment is essential. Due to their complexity these two risks are usually managed independently, yet frequently they are interconnected by longshore exchange of sediments and the resulting broad scale morphological system behaviour. Simply put, if beach levels rise or fall, flood risk in adjacent low-lying coastal areas decreases or increases respectively. In order to generate new insights into the effects of climate change and coastal management practises on coastal erosion and flood risk, we present an integrated assessment of 72 km of shoreline over the 21 st Century on the East Anglian Coast of England. A coupled system of hydrodynamic, morphological, reliability and socio-economic models has been developed for the analysis, which has been implemented under scenarios of climate and socio-economic change. The study is unique in coastal management terms because of the large spatial scale and extended temporal scales over which the analysis is quantified, but is also a site of significant controversy about how to manage coastal flood and erosion risks over the 21 st Century. This study for the first time quantifies what has for some years been argued qualitatively: the role of sediments released from cliff erosion in protecting neighbouring low-lying land from flooding. The losses and benefits are expressed using the common currency of economic risk. The analysis demonstrates that over the 21 st Century, flood risk in the study area is expected to be an order of magnitude greater than erosion risk. Both climate and socio-economic change can have a significant influence on flood risk. This study demonstrates that the choices concerning coastal management are profound, and there are clear tradeoffs between erosion and flood impacts.

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A numerical model detailing the functioning and emergent behaviour of an eroding coastal system is described. Model output from a 50-km study region centred on the soft-rock shore of northeast Norfolk was verified through comparison with cliff recession rates that were extracted from historical maps spanning more than a century. Predictions were then made for the period 2000 to 2100 under combined climatic change and management scenarios. For the scenarios evaluated, the model was relatively insensitive to increases in offshore wave height and moderately sensitive to changes in wave direction, but the most important effects were associated with accelerated sea-level rise (SLR). In contrast to predictions made using a modified version of the Bruun rule, the systems model predicted rather complex responses to SLR. For instance, on some sectors of coast, whereas the Bruun rule predicted increased recession under accelerated SLR, the systems model actually predicted progradation owing to the delivery of sediment from eroding coasts up-drift. By contrast, on coasts where beaches are underlain by shore platforms, both the Bruun rule and the systems model predicted accelerated recession rates. However, explicit consideration of the interaction between beach and shore platform within the systems model indicates that these coasts have a broader range of responses and lower overall vulnerability to SLR than predicted by the Bruun rule.

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Fundamental changes in the meaning and practice of environmental science are affecting – and are affected by – the theoretical, technological, pedagogical and institutional projects of physical geography. These changes have given rise to a range of ‘integrative’ (or integration‐directed) disciplinary narratives which articulate a role for physical geographers within an engaged project of societal relevance and transformation. In this context, we welcome the rise of a notional ‘Critical Physical Geography’ and here we seek to expand the conversation to support thinking about what it might mean to be critical within physical geography. Moving beyond definitions of interdisciplinary collaboration, we propose that being critical from within physical geography begins with cultivating a critical disposition towards the situated partiality of our scientific practices. This prompts consideration of the ways in which our environmental objects could be assembled differently, reflecting different personal histories and values, and from different epistemic locations and management framings and through different investment narratives. A critical disposition prompts reflection upon the situated constraints and opportunities presented by our institutional locations. Recognition and articulation of critical perspectives may provoke endeavours to more consciously reassemble our scientific and institutional projects into more effective interventions to secure a more powerful and meaningful role for physical geographers across their diverse engagements.

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Lord Howe Island, in the northern Tasman Sea, is a remnant of a much larger Late Miocene basaltic shield volcano. Much of the island's coastline is exposed to waves that have unlimited fetch, but a marked contrast is provided by a fringing coral reef and lagoon that very effectively attenuate wave energy along a portion of the western coastline. The geology of the island is varied, with hard and resistant basalt lavas, breccias and tuffs of intermediate resistance, and highly erodible eolianites. This variability provides an excellent opportunity to examine the influence of rock resistance on the development of the spectacular rock coast landforms that occur around the island. The hardness of rocks and the extent of weathering around the coastline were assessed using a Schmidt hammer, and statistical analysis was undertaken to remove outlying values. On all but one occasion, higher mean rebound values were returned from fresh surfaces than weathered surfaces, but only half of these differences were statistically significant. Shore platforms with two distinct levels are juxtaposed along two stretches of coastline and Schmidt hammer results lend support to hypotheses that the raised surfaces may be inherited features. Relative rock resistance was assessed through a combination of Schmidt hammer data and measurements of joint density, and constrained on the basis of morphological data. This approach formed a basis for examining threshold conditions for sea-cliff erosion at Lord Howe Island in the context of the distribution of resistant plunging cliffs and erosional shore platforms.