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Ocean acidification has become one of the most intensively studied climate change topics and it is expected to have both direct and indirect impacts on species, ecosystems, and economies. Experiments have been performed on different taxa, life stages, and at different pH levels. Despite this wealth of information, several key challenges remain, including (1) uncertainty about how to incorporate current pH ranges and variability experienced by organisms into experiments, and (2) how to bring this information together to support analysis and assessments at the broader ecosystem level. Sophisticated modelling tools are needed to 'scale-up' from experimental results to regional-scale insights. This paper highlights the challenges of combining information to determine how commercially exploited species may be affected under future pH levels, and how modelling and experimental results might be better aligned, using northwest Europe and the waters around the British Isles as an example. We argue that in most cases the current evidence does not offer sufficient information into impacts at projected pH levels, and that future experiments should be designed to consider the pH levels actually experienced by organisms, as well as variability in pH. These types of study are key in safeguarding commercially exploited shellfish stocks. [ABSTRACT FROM AUTHOR]

For those involved in planning for regional and local scale changes in future climate, there is a requirement for climate information to be available in a context more usually associated with meteorological timescales. Here we combine a tool used in numerical weather prediction, the 30 weather patterns produced by the Met Office, which are already applied operationally to numerical weather prediction models, to assess changes in the UK Climate Projections (UKCP) Global ensemble. Through assessing projected changes in the frequency of the weather patterns at the end of the 21st Century, we determine that future changes in large-scale circulation tend towards an increase in winter of weather patterns associated with cyclonic and westerly wind conditions at the expense of more anticyclonic, settled/blocked weather patterns. In summer, the results indicate a shift towards an increase in dry settled weather types with a corresponding reduction in the wet and windy weather types. Climatologically this suggests a shift towards warmer, wetter winters and warmer, drier summers; which is consistent with the headline findings from the UK Climate Projections 2018. This paper represents the first evaluation of weather patterns analysis within UKCP Global. It provides a detailed assessment of the changes in these weather patterns through the 21st Century and how uncertainty in emissions, structural and perturbed parameters affects these results. We show that the use of these weather patterns in tandem with the UKCP projections is useful for future work investigating changes in a range of weather-related climate features such as extreme precipitation. [ABSTRACT FROM AUTHOR]

This paper examines the impact that climate change may have on the lodging of oats in the Republic of Ireland and the UK. Through the consideration of a novel lodging model representing the motion of an oat plant due to the interaction of wind and rain and integrating future predictions of wind and rainfall due to climate change, appropriate conclusions have been made. In order to provide meteorological data for the lodging model, wind and rainfall inputs are analysed using 30 years' time series corresponding to peak lodging months (June and July) from 38 meteorological stations in the United Kingdom and the Irish Republic, which enables the relevant probability density functions (PDFs) to be established. Moreover, climate data for the next six decades in the British Isles produced by UK climate change projections (UKCP18) are analysed, and future wind and rainfall PDFs are obtained. It is observed that the predicted changes likely to occur during the key growing period (June to July) in the next 30 years are in keeping with variations, which can occur due to different husbandry treatments/plant varieties. In addition, the utility of a double exponential function for representing the rainfall probability has been observed with appropriate values for the constants given. [ABSTRACT FROM AUTHOR]

There are no true fir species (Abies spp.) native to the British Isles: the first to be introduced was Abies alba in the 1600s which was planted on some scale until the late 1800s when it proved vulnerable to an insect pest. Thereafter interest switched to North American species, particularly grand (Abies grandis) and noble (Abies procera) firs. Provenance tests were established for A. alba, A. amabilis, A. grandis, and A. procera. Other silver fir species were trialled in forest plots with varying success. Although species such as grand fir have proved highly productive on favourable sites, their initial slow growth on new planting sites and limited tolerance of the moist nutrient-poor soils characteristic of upland Britain restricted their use in the afforestation programmes of the last century. As a consequence, in 2010, there were about 8000 ha of Abies species in Britain, comprising less than one per cent of the forest area. Recent species trials have confirmed that best growth is on mineral soils and that, in open ground conditions, establishment takes longer than for other conifers. However, changes in forest policies increasingly favour the use of Continuous Cover Forestry and the shade tolerant nature of many fir species makes them candidates for use with selection or shelterwood silvicultural systems. Supporting evidence is provided by analysis of the regeneration in a long term study of transformation of first rotation conifer plantations. The need to adapt forests to climate change has identified some other silver fir species from southern Europe and Asia as having potential to help increase the resilience of British forests against the impacts of a warmer climate. This paper is the first review of experiments, operational experience with, and the potential role of silver firs in British forestry for more than 20 years. It suggests that previous reviews of the potential role of Abies species have been unduly pessimistic and that there should be an expanded place for silver fir species in British forestry in the future. [ABSTRACT FROM AUTHOR]

The most widespread depositional landforms in many of the upland valleys of the British Isles which have undergone glaciation during the Last Glacial Maximum (LGM) are so-called solifluction sheets. These form a landform-sediment association consisting of smoothed-slopes underlain by poorly-sorted deposits. The timing and nature of sediment deposition is unclear in the absence of a dating framework within which solifluction sheet development can be placed. This paper presents the first dates from these landforms in the British Isles. We used optical dating on deposits exposed at Linhope Burn in the Cheviot Hills of North East England. The results suggest that the bulk of sediment deposition at this site happened over a period spanning the Younger Dryas. We argue that both paraglacial and periglacial processes can account for the main periods of deposition and that the timing of sediment deposition reflects the rapidity with which landform development responded to climatic shifts. [ABSTRACT FROM AUTHOR]

Species distribution models have become a valuable tool to predict the distribution of species across geographic space and time. In this study, maximum entropy models were constructed for two temperate shallow-water octocoral species, the pink sea fan (Eunicella verrucosa) and dead man's fingers (Alcyonium digitatum), to investigate and compare habitat suitability. The study area covered the north-east Atlantic from the Bay of Biscay to the British Isles and southern Norway; this area includes both the northern range of E. verrucosa and the middle-northern range of A. digitatum. The optimal models for each species showed that, overall, slope, temperature at the seafloor and wave orbital velocity were important predictors of distribution in both species. Predictions of habitat suitability showed areas of present-day (1951-2000) suitable habitat where colonies have not yet been observed, particularly for E. verrucosa, where areas beyond its known northern range limit were identified. Moreover, analysis with future layers (2081-2100) of temperature and oxygen concentration predicted a sizable increase in habitat suitability for E. verrucosa beyond these current range limits under the Representative Concentration Pathway 8.5 scenario. This suggests that projected climate change may induce a potential range expansion northward for E. verrucosa, although successful colonisation would also be conditional on other factors such as dispersal and interspecific competition. For A. digitatum, this scenario of projected climate change may result in more suitable habitat in higher latitudes, but, as with E. verrucosa, there is a degree of uncertainty in the model predictions. Importantly, the results from this study highlight present-day areas of high habitat suitability which, if combined with knowledge on population density, could be used to identify priority areas to enhance protection and ensure the long-term survival of these octocoral species in the region. [ABSTRACT FROM AUTHOR]

The extratropical storm tracks cause much of the high-impact weather in the midlatitudes, and thus it is of interest to examine the weather impacts of projected storm track change. Here, a framework for quantifying storm track impact on precipitation over Europe developed in Part I for winter is extended to all four seasons and applied to estimate the precipitation impacts of CMIP5 and CMIP6 model projected storm track change under the high-emission scenarios. For autumn and winter, a significant portion of the projected decrease in precipitation over southern Europe and the Mediterranean Sea region can be related to a projected decrease in storm track activity over these regions. In winter, the projected increase in storm track activity near the British Isles accentuates the precipitation increase over that region. In summer, a projected storm track decrease over northern Europe is expected to give rise to a decrease in precipitation that expands the projected drying region poleward and reduces the impact of the projected high-latitude precipitation increase related to the increase in atmospheric moisture. CMIP6 models project stronger drying than CMIP5 models over central and northern Europe in summer and autumn. Part of this increased drying can be related to an enhanced decrease in storm track activity projected by CMIP6 models. Apart from multimodel mean projections, different model projected storm track change patterns can give rise to very different regional precipitation impacts, and account for the model spread in precipitation projection in many regions. What causes such model diversity should be further examined. [ABSTRACT FROM AUTHOR]

Abstract: Worldwide demand for energy is growing and predicted to increase by up to three times by 2050. Renewable energy will play a vital role in meeting this demand whilst maintaining global climate change targets. Around the British Isles, development of wind farms has entered Round three, with large, high capacity wind parks being planned to enhance energy security and achieve 2020 renewable energy targets. Such developments place additional pressure on existing sea space and may result in conflicts with other marine activities and users. Co-location of certain activities, marine protected areas, aquaculture and commercial fishing in particular, has therefore been proposed as an option to ease demands on space. Using the UK guided by EU and regional policy, as a case study, following the criteria-based planning system, co-location is legally feasible. Crucially, co-location options will depend on site specific characteristics and site management plans. The biology, ecology and hydrology of the site as well as consideration of important commercial and economic factors will be determining factors of success. For marine protected areas compatibility with conservation objectives for the site will be fundamental. Where possible, it is suggested that activities suitable for co-location will develop in tandem with renewable energy projects. The importance of developing joint projects in this manner is particularly true for aquaculture projects to ensure tenure security and commercial viability. Adaptive management will be a basis for evolution of the concept and practice of co-location. Pilot projects and continued monitoring will be essential in shaping the future of co-location of activities. As the Marine Management Organisation continues the development of marine plans for the English inshore and offshore waters, a study into potential solutions for resolving sea use conflicts is timely. This paper therefore provides a concise overview of the current regulation affecting co-location of key marine activities within wind farm zones and provides suggestions on how co-location projects can be adopted and taken forward, using the UK as a case study. [Copyright &y& Elsevier]

Abstract: Four decades of palaeosea-level research in the British Isles have produced a large dataset of age–altitude curves of postglacial sea-level changes. Patterns of late Holocene relative sea-level change reveal the persistent influence of the British/Irish Ice Sheet and the larger Scandinavian Ice Sheet on contemporary rates of vertical land movements. The map of late Holocene relative land movements has been used in future sea-level rise predictions by the United Kingdom Climate Impact Programme in their 2002 assessment (UKCIP02), but has been mistaken for a map of absolute land movements. In this paper, land-motion data for Britain are extracted from the relative sea-level data, and a new map of crustal land movements is presented which also includes Ireland. This procedure takes into account the regional 20th century sea-level rise (∼0.14m) and the process of ocean syphoning (i.e. a global fall in sea level of ∼0.3mm/yr due to GIA induced ocean-floor lowering and re-distribution of ocean mass). The calculated land-motion rates also depend on the global late Holocene ice-equivalent sea-level change, given by the Intergovernmental Panel on Climate Change as 0.0–0.2mm/yr. Accounting for these processes reduces the misfit between geological observations of vertical land motion and those independently derived from gravity-aligned Global Positioning System (AG GPS) measurements and shows that UKCIP02 has underestimated land subsidence in southern Britain and over-estimated land uplift in Scotland, both by 0.1–0.2mm/yr. A best fit between GPS and geological estimates of land movements in Britain is achieved for a global long-term eustatic sea-level fall of ca 0.2mm/yr, suggesting some global ice expansion in the late Holocene, rather than melt. If this is correct, uplift rates in Scotland would be lower and subsidence rates in southern Britain would be faster (by 0.4–0.5mm/yr) than estimated by UKCIP02. More high-quality late Holocene relative sea-level data are required to quantify vertical land motion as accurately as possible, especially near large coastal population centres, for input into regional scenarios of future sea-level rise. [Copyright &y& Elsevier]

Partitioning uncertainty in projections of future climate change into contributions from internal variability, model response uncertainty and emissions scenarios has historically relied on making assumptions about forced changes in the mean and variability. With the advent of multiple single-model initial-condition large ensembles (SMILEs), these assumptions can be scrutinized, as they allow a more robust separation between sources of uncertainty. Here, the framework from Hawkins and Sutton (2009) for uncertainty partitioning is revisited for temperature and precipitation projections using seven SMILEs and the Coupled Model Intercomparison Project CMIP5 and CMIP6 archives. The original approach is shown to work well at global scales (potential method bias < 20 %), while at local to regional scales such as British Isles temperature or Sahel precipitation, there is a notable potential method bias (up to 50 %), and more accurate partitioning of uncertainty is achieved through the use of SMILEs. Whenever internal variability and forced changes therein are important, the need to evaluate and improve the representation of variability in models is evident. The available SMILEs are shown to be a good representation of the CMIP5 model diversity in many situations, making them a useful tool for interpreting CMIP5. CMIP6 often shows larger absolute and relative model uncertainty than CMIP5, although part of this difference can be reconciled with the higher average transient climate response in CMIP6. This study demonstrates the added value of a collection of SMILEs for quantifying and diagnosing uncertainty in climate projections. [ABSTRACT FROM AUTHOR]

Palaeoecological research in the Department of Geography and Environment at the University of Aberdeen can be traced back to pollen-analytical (palynological) and geomorphological collaborations in the early 1970s. The research has generally been nested within Quaternary science and it features strong interdisciplinary links with archaeology, chronostratigraphy, climate change and ecology more generally. The pollen-based emphasis has been augmented by multi-proxy approaches including plant macro- and microfossils, geochemistry and pedology. There has always been techniques- and methodologically-orientated output and the chronological focus has spanned especially the period from the Lateglacial through to the present. With an emphasis upon research since the year 2000, the account is structured around such themes as environmental change in Scotland and the rest of the British Isles, human-environment interactions in the North Atlantic region, Patagonia and Tierra del Fuego, atmospheric pollution and metals in prehistory, and carbon sequestration and chronologies. A final section looks briefly and selectively at future research. [ABSTRACT FROM AUTHOR]

Empirical works to assist in choosing climatically relevant variables in the attempt to predict climate change impacts on plant species are limited. Further uncertainties arise in choice of an appropriate niche model. In this study we devised and tested a sharp methodological framework, based on stringent variable ranking and filtering and flexible model selection, to minimize uncertainty in both niche modelling and successive projection of plant species distributions. We used our approach to develop an accurate, parsimonious model of Silene acaulis (L.) presence/absence on the British Isles and to project its presence/absence under climate change. The approach suggests the importance of (a) defining a reduced set of climate variables, actually relevant to species presence/absence, from an extensive list of climate predictors, and (b) considering climate extremes instead of, or together with, climate averages in projections of plant species presence/absence under future climate scenarios. Our methodological approach reduced the number of relevant climate predictors by 95.23% (from 84 to only 4), while simultaneously achieving high cross-validated accuracy (97.84%) confirming enhanced model performance. Projections produced under different climate scenarios suggest that S. acaulis will likely face climate-driven fast decline in suitable areas on the British Isles, and that upward and northward shifts to occupy new climatically suitable areas are improbable in the future. Our results also imply that conservation measures for S. acaulis based upon assisted colonization are unlikely to succeed on the British Isles due to the absence of climatically suitable habitat, so different conservation actions (seed banks and/or botanical gardens) are needed. [ABSTRACT FROM AUTHOR]

The diurnal variation of the rainfall amount, frequency and intensity, and the rainfall with different durations, as well as their seasonality, were analysed by using the hourly rainfall data at 90 stations in the UK during 1998–2015. The rainfall amount averaged in the entire UK presented two comparable peaks in the early morning and the late afternoon, which contributed by the frequency (the early morning) and the intensity (the late afternoon), separately. The rainfall peaks were closely related with the location and the duration of the rainfall. For the rainfall amount, the early morning peaks were more prevailing in the rainfall events lasting more than 6 hr and at the stations along the western coast of the British Isles; however, the rainfall events lasting 1–6 hr usually reached the hourly maximum in the late afternoon. For the seasonal variability, more nocturnal rainfall peaks of rainfall amount and intensity were found over the southern plains in winter. In spring to autumn, only the rainfall at some coastal stations or the stations on islands got the maximum during midnight to the early morning. For the rainfall frequency, the regional differences were more apparent in spring and summer, and the hourly rainfall frequency in the UK mainly peaked around 0600 GMT (Greenwich mean time) in autumn and in 1100–1300 GMT in winter. The results enriched the knowledge of the hourly rainfall features over the UK. The diurnal variations in the rainfall amount, frequency and intensity, rainfall events with different durations, and their seasonality were analysed using the hourly rainfall data collected at 90 stations in the UK from 1998 to 2015. The average rainfall amount in the entire UK presented two comparable peaks in the early morning and late afternoon, which reflected contributions from the frequency (the early morning) and intensity (the late afternoon), respectively. The rainfall peaks of rainfall amount, frequency and intensity were closely related to their location and the durations. Spatial distributions of the peaks of the diurnal cycles of the hourly precipitation amount (a), frequency (b), and intensity (c) averaged during 1998–2015, as well as topography (shaded, units: m). The vectors denote the GMT at which the maximum precipitation occurred (the phase clock). [ABSTRACT FROM AUTHOR]

Blocking anticyclonic circulations from Europe are provoking climatic episodes responsible for discomfort, human and financial loses. During the summer, these episodes are known for prolonged droughts and maximum temperatures often exceeding 35 °C to 40 °C. In the cold season, the rainfalls are close to 0 while the daily minimum temperatures are low under the average period. For this study, we used a synoptic classification which is available especially for Central Europe but works similarly for Romanian territory too. We aim to follow what kind of climatic conditions these circulations are producing in Romania during their presence in Europe. ECA&D daily gridded climatic dataset was used in this study. The study period lasts from 1961 to 2012. We used the minimum and maximum daily temperatures as well the rainfall quantities recorded. Since the output volume of data was too high, we aggregated the results into yearly multiseasonal average. In order to classify the synoptic patterns as blocking anticyclones, we used two synoptic situations from Hess-Brezowsky defined as Anticyclone High Central (HM) and High British Isles (HB). We calculated the thermic anomalies as well the rainfall quantities recorded in Romania during the presence of these circulations in central Europe. The results shows a perspective over the synoptic conditions in Romania during the presence of the above mentioned synoptic types in Central Europe. [ABSTRACT FROM AUTHOR]

This account presents information on all aspects of the biology of Ambrosia artemisiifolia L. (Common ragweed) that are relevant to understanding its ecology. The main topics are presented within the standard framework of the Biological Flora of the British Isles: distribution, habitat, communities, responses to biotic factors, responses to environment, structure and physiology, phenology, floral and seed characters, herbivores and disease, and history, conservation, impacts and management., Ambrosia artemisiifolia is a monoecious, wind-pollinated, annual herb native to North America whose height varies from 10 cm to 2.5 m, according to environmental conditions. It has erect, branched stems and pinnately lobed leaves. Spike-like racemes of male capitula composed of staminate (male) florets terminate the stems, while cyme-like clusters of pistillate (female) florets are arranged in groups in the axils of main and lateral stem leaves., Seeds require prolonged chilling to break dormancy. Following seedling emergence in spring, the rate of vegetative growth depends on temperature, but development occurs over a wide thermal range. In temperate European climates, male and female flowers are produced from summer to early autumn (July to October)., Ambrosia artemisiifolia is sensitive to freezing. Late spring frosts kill seedlings and the first autumn frosts terminate the growing season. It has a preference for dry soils of intermediate to rich nutrient level., Ambrosia artemisiifolia was introduced into Europe with seed imports from North America in the 19th century. Since World War II, it has become widespread in temperate regions of Europe and is now abundant in open, disturbed habitats as a ruderal and agricultural weed., Recently, the North American ragweed leaf beetle ( Ophraella communa) has been detected in southern Switzerland and northern Italy. This species appears to have the capacity to substantially reduce growth and seed production of A. artemisiifolia., In heavily infested regions of Europe, A. artemisiifolia causes substantial crop-yield losses and its copious, highly allergenic pollen creates considerable public health problems. There is a consensus among models that climate change will allow its northward and uphill spread in Europe. [ABSTRACT FROM AUTHOR]

Recent climatic change has been recorded across the globe. Although environmental change is a characteristic feature of life on Earth and has played a major role in the evolution and global distribution of biodiversity, predicted future rates of climatic change, especially in temperature, are such that they will exceed any that has occurred over recent geological time. Climate change is considered as a key threat to biodiversity and to the structure and function of ecosystems that may already be subject to significant anthropogenic stress. The current understanding of climate change and its likely consequences for the fishes of Britain and Ireland and the surrounding seas are reviewed through a series of case studies detailing the likely response of several marine, diadromous and freshwater fishes to climate change. Changes in climate, and in particular, temperature have and will continue to affect fish at all levels of biological organization: cellular, individual, population, species, community and ecosystem, influencing physiological and ecological processes in a number of direct, indirect and complex ways. The response of fishes and of other aquatic taxa will vary according to their tolerances and life stage and are complex and difficult to predict. Fishes may respond directly to climate-change-related shifts in environmental processes or indirectly to other influences, such as community-level interactions with other taxa. However, the ability to adapt to the predicted changes in climate will vary between species and between habitats and there will be winners and losers. In marine habitats, recent changes in fish community structure will continue as fishes shift their distributions relative to their temperature preferences. This may lead to the loss of some economically important cold-adapted species such as Gadus morhua and Clupea harengus from some areas around Britain and Ireland, and the establishment of some new, warm-adapted species. Increased temperatures are likely to favour cool-adapted ( e.g. Perca fluviatilis) and warm-adapted freshwater fishes ( e.g. roach Rutilus rutilus and other cyprinids) whose distribution and reproductive success may currently be constrained by temperature rather than by cold-adapted species ( e.g. salmonids). Species that occur in Britain and Ireland that are at the edge of their distribution will be most affected, both negatively and positively. Populations of conservation importance ( e.g. Salvelinus alpinus and Coregonus spp.) may decline irreversibly. However, changes in food-web dynamics and physiological adaptation, for example because of climate change, may obscure or alter predicted responses. The residual inertia in climate systems is such that even a complete cessation in emissions would still leave fishes exposed to continued climate change for at least half a century. Hence, regardless of the success or failure of programmes aimed at curbing climate change, major changes in fish communities can be expected over the next 50 years with a concomitant need to adapt management strategies accordingly. [ABSTRACT FROM AUTHOR]

Climate change may increase the number and distribution of alien plant species, where these taxa are better suited to future climates, comprise life-forms known to benefit from a warmer environment, and/or possess life-history traits that facilitate the rapid tracking of climate change. Sequential atlases of the British flora enable assessment of the role of climate in changes in native and alien plant distributions over the latter half of the 20th century, a period coincident with marked climatic warming. While the climate profiles (e.g. frost-sensitive) and life-forms (e.g. therophytes and geophytes) of aliens suggest a high likelihood of becoming more widespread under a warmer, drier climate, this is not evident from changes in distributions since the 1960s. The strong association of aliens with anthropogenic habitats and the tendency for species spread to consolidate occupancy within the current range rather than extending range boundaries, indicate that land-use change may be a driver of species distributions. Nevertheless, problems arising from the consolidation of a species range may warrant as much concern as any poleward expansion of its distribution. While certain species may respond more to future climates than others, changes in the alien flora as a whole will probably also reflect other drivers, such as land use, propagule pressure and human-mediated dispersal. The importance of land-use change in the spread of alien plants is expected to continue even in the face of future climate change, not only in the UK, but also worldwide. [ABSTRACT FROM AUTHOR]

We use field observations in two geographic regions within the British Isles and regression and neural network models to examine the relationship between microhabitat use, thoracic temperatures and activity in a widespread lycaenid butterfly, Polyommatus icarus. We also make predictions for future activity under climate change scenarios. Individuals from a univoltine northern population initiated flight with significantly lower thoracic temperatures than individuals from a bivoltine southern population. Activity is dependent on body temperature and neural network models of body temperature are better at predicting body temperature than generalized linear models. Neural network models of activity with a sole input of predicted body temperature (using weather and microclimate variables) are good predictors of observed activity and were better predictors than generalized linear models. By modelling activity under climate change scenarios for 2080 we predict differences in activity in relation to both regional differences of climate change and differing body temperature requirements for activity in different populations. Under average conditions for low-emission scenarios there will be little change in the activity of individuals from central-southern Britain and a reduction in northwest Scotland from 2003 activity levels. Under high-emission scenarios, flight-dependent activity in northwest Scotland will increase the greatest, despite smaller predicted increases in temperature and decreases in cloud cover. We suggest that neural network models are an effective way of predicting future activity in changing climates for microhabitat-specialist butterflies and that regional differences in the thermoregulatory response of populations will have profound effects on how they respond to climate change. [ABSTRACT FROM AUTHOR]

The winter climate of the British Isles is characterized by considerable interannual variability, which, because of the general climate sensitivity of a number of health outcomes, places at times considerable pressure on the provision of health services. Seasonal climate forecasts potentially could improve management within the health sector and assist in hedging against the vagaries of climatic variability. For this reason, an exploratory analysis of the potential utility of seasonal climate forecasting for the health sector in the United Kingdom is presented here. Study results revealed that the general level of winter mortality at the monthly to seasonal time scale possesses a strong association with simple descriptors of winter climate such as maximum temperature and the number of days below a given temperature threshold. Because such climate indices can be derived from the output of coupled seasonal climate prediction models, predictions of general levels of mortality may be possible using simple transfer functions that describe winter climate and health associations. Despite the potential one-month-ahead and one-season-ahead predictability of winter mortality levels, the predictability of the key climate indices by coupled climate models is shown to be somewhat limited, which compromises the ability to predict general levels of winter mortality for all months except February. [ABSTRACT FROM AUTHOR]

An ensemble of regional climate change scenarios for the North Sea is validated and analyzed. Five Coupled Model Intercomparison Project Phase 5 (CMIP5) General Circulation Models (GCMs) using three different Representative Concentration Pathways (RCPs) have been downscaled with the coupled atmosphere–ice–ocean model RCA4-NEMO. Validation of sea surface temperature (SST) against different datasets suggests that the model results are well within the spread of observational datasets. The ensemble mean SST with a bias of less than 1 ∘ C is the solution that fits the observations best and underlines the importance of ensemble modeling. The exchange of momentum, heat, and freshwater between atmosphere and ocean in the regional, coupled model compares well with available datasets. The climatological seasonal cycles of these fluxes are within the 95% confidence limits of the datasets. Towards the end of the 21st century the projected North Sea SST increases by 1.5 ∘ C (RCP 2.6), 2 ∘ C (RCP 4.5), and 4 ∘ C (RCP 8.5), respectively. Under this change the North Sea develops a specific pattern of the climate change signal for the air–sea temperature difference and latent heat flux in the RCP 4.5 and 8.5 scenarios. In the RCP 8.5 scenario the amplitude of the spatial heat flux anomaly increases to 5 W/m 2 at the end of the century. Different hypotheses are discussed that could contribute to the spatially non-uniform change in air–sea interaction. The most likely cause for an increased latent heat loss in the central western North Sea is a drier atmosphere towards the end of the century. Drier air in the lee of the British Isles affects the balance of the surface heat budget of the North Sea. This effect is an example of how regional characteristics modulate global climate change. For climate change projections on regional scales it is important to resolve processes and feedbacks at regional scales. [ABSTRACT FROM AUTHOR]