Transport accessibility is an important driver of urban growth and key to the sustainable development of cities. This paper presents a simple GIS-based tool developed to allow the rapid analysis of accessibility by different transport modes. Designed to be flexible and use publicly-available data, this tool (built in ArcGIS) uses generalized cost to measure transport costs across networks including monetary and distance components. The utility of the tool is demonstrated on London, UK, showing the differing patterns of accessibility across the city by different modes. It is shown that these patterns can be examined spatially, by accessibility to particular destinations (e.g., employment locations), or as a global measure across a whole city system. A number of future infrastructure scenarios are tested, examining the potential for increasing the use of low-carbon forms of transport. It is shown that private car journeys are still the least cost mode choice in London, but that infrastructure investments can play a part in reducing the cost of more sustainable transport options.

Critical national infrastructures, including energy, transport, digital communications, and water, are prone to flood damage. Their geographical extent is a determinant of, and is determined by, patterns of human development, which is often concentrated in floodplains. It is important to understand how infrastructure systems react to large‐scale flooding. In this paper, we present an integrated framework for critical infrastructure flood impact assessment. Within this integrated framework, we represent interdependent infrastructure assets through spatial network models. We quantify infrastructure flood impacts in terms of disrupted customers linked directly to flood assets and customers disrupted indirectly due to network effects. The analysis shows how spatial network models inform flood risk management practitioners to identify and compare critical infrastructures risks on flooded and non‐flooded land, for prioritising flood protection investments and improve resilience of cities. A case study of the Thames catchment in England is presented, which contains key infrastructure assets and highest population concentrations in United Kingdom.

We have measured the surface flow rate of the large east Greenland glacier, Sortebræ, through both the initiation and termination of a major surge using synthetic aperture radar (SAR) feature tracking, optimized to minimize error. The Sortebræ surge began between November and January 1992–1993, after at least 6 weeks of subfreezing temperatures over the whole glacier, and propagated rapidly up‐glacier from a central nucleus. Sortebræ reached sustained fast flow rates of up to 24 m d−1, and the active phase lasted for 28–32 months before terminating in June 1995. Termination was abrupt, coinciding with the arrival of the spring thaw and the apparent release of a large volume of stored water from a single outlet at the front. The surge mechanism is interpreted as a switch from channelized to distributed drainage, which at present is best explained by Kamb's linked cavity sliding model.

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