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Recent extreme weather events have had severe impacts on UK crop yields, and so there is concern that a greater frequency of extremes could affect crop production in a changing climate. Here we investigate the impacts of future climate change on wheat, the most widely grown cereal crop globally, in a temperate country with currently favourable wheat-growing conditions. Historically, following the plateau of UK wheat yields since the 1990s, we find there has been a recent significant increase in wheat yield volatility, which is only partially explained by seasonal metrics of temperature and precipitation across key wheat growth stages (foundation, construction and production). We find climate impacts on wheat yields are strongest in years with compound weather extremes across multiple growth stages (e.g. frost and heavy rainfall). To assess how these conditions might evolve in the future, we analyse the latest 2.2 km UK Climate Projections (UKCP Local): on average, the foundation growth stage (broadly 1 October to 9 April) is likely to become warmer and wetter, while the construction (10 April to 10 June) and production (11 June to 26 July) stages are likely to become warmer and slightly drier. Statistical wheat yield projections, obtained by driving the regression model with UKCP Local simulations of precipitation and temperature for the UK's three main wheat-growing regions, indicate continued growth of crop yields in the coming decades. Significantly warmer projected winter night temperatures offset the negative impacts of increasing rainfall during the foundation stage, while warmer day temperatures and drier conditions are generally beneficial to yields in the production stage. This work suggests that on average, at the regional scale, climate change is likely to have more positive impacts on UK wheat yields than previously considered. Against this background of positive change, however, our work illustrates that wheat farming in the UK is likely to move outside of the climatic envelope that it has previously experienced, increasing the risk of unseen weather conditions such as intense local thunderstorms or prolonged droughts, which are beyond the scope of this paper. [ABSTRACT FROM AUTHOR]

Managing urban flood risk is a key global challenge of the twenty-first century. Drivers of future UK flood risk were identified and assessed by the Flood Foresight project in 2002–2004 and 2008; envisaging flood risk during the 2050s and 2080s under a range of scenarios for climate change and socio-economic development. This paper qualitatively reassesses and updates these drivers, using empirical evidence and advances in flood risk science, technology and practice gained since 2008. Of the original drivers, five have strengthened, three have weakened and 14 remain within their 2008 uncertainty bands. Rainfall, as impacted by climate change, is the leading source driver of future urban flood risk. Intra-urban asset deterioration, leading to increases in a range of consequential flood risks, is the primary pathway driver. Social impacts (risk to life and health, and the intangible impacts of flooding on communities) and continued capital investment in buildings and contents (leading to greater losses when newer buildings of higher economic worth are inundated) have strengthened as receptor drivers of urban flood risk. Further, we propose two new drivers: loss of floodable urban spaces and indirect economic impacts, which we suggest may have significant impacts on future urban flood risk. This article is part of the theme issue 'Urban flood resilience'. [ABSTRACT FROM AUTHOR]

Sewer flooding, urban surface water flooding and wet weather pollution are recognised as significant problems in the UK and elsewhere in the world, and changes in extreme rainfall arising as a consequence of climate change are likely to exacerbate these problems. This paper reports on new approaches to estimate potential future rainfall intensity changes over the UK at temporal and spatial scales that impact on urban drainage systems. The research (part of UK Water Industry Research's programme of climate change related projects) has produced estimates of rainfall intensity change over different parts of the UK using a climate analogue approach and a very high-resolution (1·5 km) climate model developed by the UK Met Office. The new estimates produced are, in general, higher than existing UK climate change allowances for rainfall intensity. Sewer flooding volumes, flooding frequency and frequency of pollution events are also investigated for one location; indicating that these incidents and flood volumes are also likely to increase in the future. [ABSTRACT FROM AUTHOR]

Climate change modelling has improved significantly in recent years and the impact of climate change on flooding in the UK and internationally has become an area of increased importance. Flooding in the UK occurs for a range of reasons; this paper examines some of the predicted changes related to rainfall processes. The different types of rainfall in the UK can be categorised into groups such as frontal, orographic and convective, and combinations of these. Notable flooding events in the UK in recent years have been caused by different types of rainfall; Boscastle in 2004 and the widespread autumn 2000 floods being examples of quite different rainfall processes. Predicting how different types of flood-producing rainfall will change in the future climate presents researchers with major challenges, including that of spatial scale and uncertainty in the predictions. This paper highlights some of these challenges and looks at areas where future research could be focused. [ABSTRACT FROM AUTHOR]

Climate change is expected to modify rainfall, temperature and catchment hydrological responses across the world, and adapting to these water-related changes is a pressing challenge. This paper reviews the impact of anthropogenic climate change on water in the UK and looks at projections of future change. The natural variability of the UK climate makes change hard to detect; only historical increases in air temperature can be attributed to anthropogenic climate forcing, but over the last 50 years more winter rainfall has been falling in intense events. Future changes in rainfall and evapotranspiration could lead to changed flow regimes and impacts on water quality, aquatic ecosystems and water availability. Summer flows may decrease on average, but floods may become larger and more frequent. River and lake water quality may decline as a result of higher water temperatures, lower river flows and increased algal blooms in summer, and because of higher flows in the winter. In communicating this important work, researchers should pay particular attention to explaining confidence and uncertainty clearly. Much of the relevant research is either global or highly localized: decision-makers would benefit from more studies that address water and climate change at a spatial and temporal scale appropriate for the decisions they make. [ABSTRACT FROM AUTHOR]

This paper describes a novel technique for downscaling daily rainfall which uses a combination of a generalised linear model (GLM) and artificial neural network (ANN) to downscale rainfall. A two-stage process is applied, an occurrence process which uses the GLM model and an amount process which uses an ANN model trained with a Levenberg--Marquardt approach. The GLM-ANN was compared with other three downscaling models, the traditional neural network (ANN), multiple linear regression (MLR) and Poisson regression (PR). The models are applied for downscaling daily rainfall at three locations in the North West of England during the winter and summer. Model performances with respect to reproduction of various statistics such as correlation coefficient, autocorrelation, root mean square errors (RMSE), standard deviation and the mean rainfall are examined. It is found that the GLM-ANN model performs better than the other three models in reproducing most daily rainfall statistics, with slight difficulties in predicting extremes rainfall event in summer. The GLM-ANN model is then used to project future rainfall at the three locations employing three different general circulation models (GCMs) for SRES scenarios A2 and B2. The study projects significant increases in mean daily rainfall at most locations for winter and decreases in summer. [ABSTRACT FROM AUTHOR]

Internationally, agriculture is widely regarded as one of the sectors at most risk from a changing climate. This is due to the impact of increased temperatures, reduced rainfall and increased frequency of extreme events, not only in the tropics but also in temperate environments. In the UK, growers also face a range of 'non-climate' risks, which, it is often argued, present a potentially greater and more immediate threat to sustainable food production than climate change. This paper highlights the climate and non-climate impacts on crop production, the adaptation options and the institutional and regulatory barriers to their uptake by farmers. It concludes that there are likely to be both positive impacts (for example, yield gains) and negative impacts (for example, increased water stress). Either way, there will be a need for new investments in adaptive management and technology, including new collaborations between the public and private sectors, to enable UK agriculture to respond to the potential effects of climate change. [ABSTRACT FROM AUTHOR]