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• Impact and uncertainty framework for the identification of compound hydro-hazards. • UK example application using EDgE RCP8.5 projections. • NE Scotland and SW UK identified as spatio-temporally compound hotspot regions. • Hydrological models identified as the largest source of variability. • Raises questions regarding spatial variability of hydroclimatological modelling uncertainty. There exists an increasing need to understand the impact of climate change on the hydrological extremes of flood and drought, collectively referred to as 'hydro-hazards'. At present, current methodology are limited in their scope, particularly with respect to inadequate representation of the uncertainty in the hydroclimatological modelling chain. This paper proposes spatially consistent comprehensive impact and uncertainty methodological framework for the identification of compound hydro-hazard hotspots – hotspots of change where concurrent increase in mean annual flood and drought events is projected. We apply a quasi-ergodic analysis of variance (QE-ANOVA) framework, to detail both the magnitude and the sources of uncertainty in the modelling chain for the mean projected mean change signal whilst accounting for non-stationarity. The framework is designed for application across a wide geographical range and is thus readily transferable. We illustrate the ability of the framework through application to 239 UK catchments based on hydroclimatological projections from the EDgE project (5 CMI5-GCMs and 3 HMs, forced under RCP8.5). The results indicate that half of the projected hotspots are temporally concurrent or temporally successive within the year, exacerbating potential impacts on society. The north-east of Scotland and south-west of the UK were identified as spatio-temporally compound hotspot regions and are of particular concern. This intensification of the hydrologic dynamic (timing and seasonality of hydro-hazards) over a limited time frame represents a major challenge for future water management. Hydrological models were identified as the largest source of variability, in some instances exceeding 80% of the total variance. Critically, clear spatial variability in the sources of modelling uncertainty was also observed; highlighting the need to apply a spatially consistent methodology, such as that presented. This application raises important questions regarding the spatial variability of hydroclimatological modelling uncertainty. In terms of water management planning, such findings allow for more focussed studies with a view to improving the projections which inform the adaptation process. [ABSTRACT FROM AUTHOR]

Loch Leven is a large, shallow lake in lowland Scotland, UK. Scientific research began here almost 200 years ago. Early research characterised the biodiversity and physical characteristics of the loch, providing an important historical background for future research. In the mid-1960s, this ad hoc approach was superseded by a more structured research programme under the umbrella of the International Biological Programme. This was the beginning of the Loch Leven long-term monitoring programme. Today, the results of these studies form one of the longest and most comprehensive limnological datasets for shallow freshwater lakes in the world, comprising more than 500 physical, chemical and biological variables collected at two-weekly intervals. To celebrate the 40th anniversary of the start of the long term monitoring programme, and to highlight the scientific investigations still being conducted at Loch Leven, the NERC Centre for Ecology & Hydrology (CEH) organised a symposium entitled "Loch Leven: 40 years of scientific research" in Kinross, Scotland, UK, on 11 December 2008. This examined the role of long-term monitoring in developing our understanding of the links between pollution, climate change and ecological responses in shallow lakes. This article introduces a series of papers summarising the scientific results presented at this meeting. [ABSTRACT FROM AUTHOR]

With evidence suggesting that climate change is resulting in changes within the hydrologic cycle, the ability to robustly model hydroclimatic response is critical. This paper assesses how extreme runoff—1:2- and 1:30-year return period (RP) events—may change at a regional level across the UK by the 2080s (2069–2098). Capturing uncertainty in the hydroclimatic modelling chain, flow projections were extracted from the EDgE (End-to-end Demonstrator for improved decision-making in the water sector in Europe) multi-model ensemble: five Coupled Model Intercomparison Project (CMIP5) General Circulation Models and four hydrological models forced under emissions scenarios Representative Concentration Pathway (RCP) 2.6 and RCP 8.5 (5 × 4 × 2 chains). Uncertainty in extreme value parameterisation was captured through consideration of two methods: generalised extreme value (GEV) and generalised logistic (GL). The method was applied across 192 catchments and aggregated to eight regions. The results suggest that, by the 2080s, many regions could experience large increases in extreme runoff, with a maximum mean change signal of +34% exhibited in East Scotland (1:2-year RP). Combined with increasing urbanisation, these estimates paint a concerning picture for the future UK flood landscape. Model chain uncertainty was found to increase by the 2080s, though extreme value (EV) parameter uncertainty becomes dominant at the 1:30-year RP (exceeding 60% in some regions), highlighting the importance of capturing both the associated EV parameter and ensemble uncertainty. [ABSTRACT FROM AUTHOR]

We begin our April issue with a paper describing the developments and effects of storm ‘Katie’, which brought significant effects to the United Kingdom on Easter Monday, 2015. In ‘Storm Katie – Rapid cyclogenesis and damaging winds of Easter Monday 2016’ on p. 103, Steven Ramsdale and Jason Kelly describe the meteorological developments that developed this low‐pressure system, the uncertainties associated with its development, the warnings issued and the damage caused, in part limited by its presence on a Bank Holiday. On p. 109, Colin Clark describes a flood 112 years ago in ‘The storm and flood of 13 May 1906 at Mells, Somerset, UK’ Dr Clark discusses the significance of the flood and its possible return period using synoptic charts of the time and descriptions published in local newspapers immediately following the event, emphasising our need to know more about floods in history. One of the least explored parts of the Middle East is the Empty Quarter. In the 1940s and 50s, the English explorer and writer Wilfred Thesiger crossed this area of extreme aridity. His discoveries and travels are described by Michael de Villiers in ‘Thesiger's weather in the Arabian Peninsula’ on p. 120. On p. 123, we present Iain Cameron and Adam Watson's annual review of the survival of snow on Scottish mountains. The overall warmth of last year is reflected in this year's title: ‘No Scottish snow patches survive until winter 2017/2018’. Weather and climate have a significant effect on human life and this journal often describes significant weather events, especially those that have affected Britain. But the local variability of weather may arguably present a more significant effect – not least, in the Developing World. Many factors affect school attendance, but weather and climate, including drought, rainstorms and dust pose important challenges, sometimes because of the secondary effects. Joseph Adejuwon discusses these effects in the Sahel zone in ‘Climate variability and the dichotomy in male–female school attendance: a case study of Zamfara State in semi‐arid Nigeria’ on p. 125. [ABSTRACT FROM AUTHOR]