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Pluvial flooding is a result of overland flow and ponding before the runoff enters any watercourse, drainage system or sewer, or cannot enter it because the network is full to capacity, usually caused by intense rainfall. River and coastal floods get the most attention since they are largest and last the longest, while pluvial floods are relatively marginalized in research. Therefore, the main goal of this research was to show risk posed by pluvial floods, their connection to current global climate change processes, present effects of flooding in European cities, as well as what we can expect in the future. Furthermore, the aims were to present and get more familiar with scientific projects, strategies, directives and measures devised both on national and international levels, that deal with urban pluvial flood issues across the European continent. Climate change projections indicate that there will be an increase in the frequency and intensity of rainfall events throughout Europe and along with ongoing urbanization, the problem of pluvial flooding will most certainly require more attention, which it is starting to receive. Some countries have already developed their strategies and initiatives and implemented both structural and non-structural measures, such as spatial planning, constructional measures, information systems, reducing land sealing through policies, building codes and standards, on-site improvement of retention, infiltration, evaporation, and rainfall water recycling with the use of green roofs, permeable or porous pavements, rain gardening or urban rainwater harvesting. At the same time, there are numerous research papers, studies, conferences and workshops devoted to the problem of pluvial flooding and its management carried out in an attempt to properly deal with this hazard. [ABSTRACT FROM AUTHOR]

The connections of climatic variables to zoonotic and wildlife diseases remain uncertain. Here, we compiled a systematic database for the prevalence of 121 pathogenic microbial taxa in birds (ca 376 species) and bats (ca 39 species), including 11 939 observations from over 450 000 individuals across Europe and surrounding regions. We modelled the potential connection of climatic variables with the prevalence of 75 pathogenic microbial taxa at a multi‐pathogenic‐taxa level and of 17 most‐studied pathogenic taxa at a single‐pathogenic‐taxon level. According to the multi‐taxa model, the prevalence of bacterial taxa was positively associated with temperature, while this association was significantly weaker for eukaryotes and viruses. The prevalence of bacterial taxa was negatively associated with rainfall, while viruses showed a positive association with rainfall. These associations between climatic variables and prevalence of pathogenic taxa were not different between bird and bat hosts. According to the single‐taxon models, the prevalence of influenza A viruses, Plasmodium, and several bacterial taxa in birds and bats was positively associated with temperature. Rainfall showed positive associations with the prevalence of Usutu, Sindbis and Influenza A viruses but the directions of significant associations varied among bacterial taxa. Strikingly, this was evidenced also between bacterial taxa that share hosts and transmission mechanism hinting towards hitherto unknown features on pathogen ecology, e.g. Salmonella versus Campylobacter and Anaplasma versus Borrelia. Our results suggest that rising temperature and increasing precipitation will accelerate the threat of bird‐ and bat‐associated bacterial and viral pathogens to wildlife, domesticated animals and humans, respectively. However, the idiosyncratic relationships with climatic conditions among pathogenic taxa highlight the need for pathogen‐specific predictive models to understand future pathogen distributions. [ABSTRACT FROM AUTHOR]

Regional climate change affects the state of inland water bodies and their water balance, which is determined by a number of hydrometeorological and hydrogeological factors. An integral characteristic of changes in the water balance is the behavior of the level of lakes and reservoirs, which not only largely determines the physical and ecological state of water bodies, but also significantly affects the coastal infrastructure and socio-economic development of the region. This paper investigates the interannual variability of the level of the Ladoga and Onega lakes, the largest lakes in Europe located in the northwest of Russia, according to satellite altimetry data for 1993–2020. For this purpose, we used three specialized altimetry databases: DAHITI, G-REALM, and HYDROWEB. Water level data from these altimetry databases were compared with in-situ records at water level gauge stations. Information on air temperature (1945–2019) and precipitation (1966–2019) acquired at three meteostations located at Ladoga and Onega lakes was used to investigate interannual trends in the regional climate change. Finally, we discuss the potential impact of the lake level rise and regional climate warming on the infrastructure and operability of railways in this region. [ABSTRACT FROM AUTHOR]

Satellite-derived high-resolution precipitation products (HRPP) have been developed to address the needs of the user community and are now available with 0.25° × 0.25° (or less) subdaily resolutions. This paper evaluates a number of commonly available satellite-derived HRPPs covering northwest Europe over a 6-yr period. Precipitation products include the Tropical Rainfall Measuring Mission (TRMM) Multisatellite Precipitation Analysis (TMPA), the Climate Prediction Center (CPC) morphing (CMORPH) technique, the CPC merged microwave technique, the Naval Research Laboratory (NRL) blended technique, and the Precipitation Estimation from Remotely Sensed Information using Artificial Neural Networks (PERSIANN) technique. In addition, the Geosynchronous Operational Environmental Satellite (GOES) precipitation index (GPI) and the European Centre for Medium-Range Weather Forecasting (ECMWF) operational forecast model products are included for comparison. Surface reference data from the European radar network is used as ground truth, supported by the Global Precipitation Climatology Centre (GPCC) precipitation gauge analysis and gauge data over the United Kingdom. Measures of correlation, bias ratio, probability of detection, and false alarm ratio are used to evaluate the products. Results show that satellite products generally exhibit a seasonal cycle in correlation, bias ratio, probability of detection, and false alarm ratio, with poorer statistics during the winter. The ECMWF model also shows a seasonal cycle in the correlation, although the results are poorer during the summer, while the bias ratio, probability of detection, and false alarm ratio are consistent through all seasons. Importantly, all the satellite HRPPs underestimate precipitation over northwest Europe in all seasons. [ABSTRACT FROM AUTHOR]

For building appropriate local/national adaptation and mitigation strategies, detailed analysis of regional climate change is essential. In order to estimate the climate change for the 21st century, both global and regional models may be used. However, due to the coarse horizontal resolution, global climate models are not appropriate to describe regional scale climate processes. On the other hand, regional climate models (RCMs) provide more realistic regional climate scenarios. A wide range of RCM experiments was accomplished in the frame of the ENSEMBLES project funded by the EU FP6 program, which was one of the largest climate change research project ever completed. All the RCM experiments used 25 km horizontal resolution and the A1B emission scenario, according to which CO2 concentration by 2100 is estimated to exceed 700 ppm, i.e., more than twice of the preindustrial level. The 25 km spatial resolution is fine enough to estimate the future hydrology-related conditions in different parts of Europe, from which we separated and analyzed simulated climate data sets for the Central/Eastern European region. Precipitation is an especially important climatological variable because of agricultural aspects and floodrelated natural hazards, which may seriously affect all the countries in the evaluated region. On the basis of our results, different RCM simulations generally project drier summers and wetter winters (compared to the recent decades). The southern countries are more likely to suffer more intense warming, especially, in summer, and also, more intense drought events due to the stronger Mediterranean impact. [ABSTRACT FROM AUTHOR]

In this study, we aim to better understand the current and future projections of precipitation extremes in Europe in the context of climatic variability over a long-term period from the last millennium to the end of the twenty- first century. The daily gridded precipitation data from five global climate models (GCMs) of phase 5 of the Coupled Model Intercomparison Project (CMIP5) are chosen to investigate natural variability and precipitation extremes during the last millennium (850-1849), the historical (1850-2005) period, and two representative concentration pathway (RCP2.6 and RCP8.5) scenarios (2006-99). First, the seasonal and annual precipitation and extreme statistics from GCMs are evaluated using reconstruction and observation. Second, the spatial and temporal patterns of extreme precipitation from GCMs are investigated from the last millennium to the end of the twenty-first century. Meanwhile, the characteristic changes of extreme precipitation for the five regions of Europe are further analyzed. The results revealed the following: GCMs underestimate extreme precipitation and overestimate mean precipitation compared with the observations from European Climate Assessment and Dataset (ECA&D) ; the majority of Europe except southern Europe will most likely have large magnitude increases in the extreme precipitation and mean precipitation in the future under both RCP scenarios; there is no systematic change of precipitation extremes from the last millennium to the historical period from all GCMs; and larger magnitude increases are shown in 100- and 200-yr than in 5- and 10-yr return period precipitation from both RCP scenarios. In addition, short-duration extreme precipitation willmost likely increase more than longer-duration extremes. [ABSTRACT FROM AUTHOR]

Wintertime midlatitude cyclone activity and precipitation are projected to increase across northern Europe and decrease over southern Europe, particularly over the western Mediterranean. Greater confidence in these regional projections may be established by their replication in state-of-the-art, high-resolution global climate models that resolve synoptic-scale dynamics. We evaluated the representation of the wintertime eddy-driven and subtropical jet streams, extratropical cyclone activity, and precipitation across the North Atlantic and Europe under historical (1985–2011) and RCP8.5 sea surface temperature forcing in an ensemble of atmosphere-only HadGEM3-GA3.0 simulations, where horizontal atmospheric resolution is increased from 135 to 25 km. Under RCP8.5, increased (decreased) frequency of northern (southern) eddy-driven jet occurrences and a basinwide poleward shift in the upper-level westerly flow are simulated. Increasing atmospheric resolution significantly enhances these climate change responses. At 25-km resolution, these enhanced changes in large-scale circulation amplify increases (decreases) in extratropical cyclone track density and mean intensity across the northern (southern) Euro-Atlantic region under RCP8.5. These synoptic changes with resolution impact the overall climate change response of mean and heavy winter precipitation: wetter (drier) conditions in northern (southern) Europe are also amplified at 25-km resolution. For example, the reduction in heavy precipitation simulated over the Iberian Peninsula under RCP8.5 is ~15% at 135 km but ~30% at 25-km resolution. Conversely, a shift to more frequent high extratropical cyclone (ETC)-associated precipitation rates is simulated over Scandinavia under RCP8.5, which is enhanced at 25 km. This study provides evidence that global atmospheric resolution may be a crucial consideration in European winter climate change projections. [ABSTRACT FROM AUTHOR]

Producing reliable estimates of changes in precipitation at local and regional scales remains an important challenge in climate science. Statistical downscaling methods are often utilized to bridge the gap between the coarse resolution of general circulation models (GCMs) and the higher resolutions at which information is required by end users. As the skill of GCM precipitation, particularly in simulating temporal variability, is not fully understood, statistical downscaling typically adopts a perfect prognosis (PP) approach in which high-resolution precipitation projections are based on real-world statistical relationships between large-scale atmospheric predictors and local-scale precipitation. Using a nudged simulation of the ECHAM5 GCM, in which the large-scale weather states are forced toward observations of large-scale circulation and temperature for the period 1958-2001, previous work has shown ECHAM5 skill in simulating temporal variability of precipitation to be high in many parts of the world. Here, the same nudged simulation is used in an alternative downscaling approach, based on model output statistics (MOS), in which statistical corrections are derived for simulated precipitation. Cross-validated MOS corrections based on maximum covariance analysis (MCA) and principal component regression (PCR), in addition to a simple local scaling, are shown to perform strongly throughout much of the extratropics. Correlation between downscaled and observed monthly-mean precipitation is as high as 0.8-0.9 in many parts of Europe, North America, and Australia. For these regions, MOS clearly outperforms PP methods that use temperature and circulation as predictors. The strong performance of MOS makes such an approach to downscaling attractive and potentially applicable to climate change simulations. [ABSTRACT FROM AUTHOR]

Daily rain gauge data over Europe for the period from 1950 to 2009 were used to analyze changes in the duration of wet and dry spells. The duration of wet spells exhibits a statistically significant growth over northern Europe and central European Russia, which is especially pronounced in winter when the mean duration of wet periods increased by 15%-20%. In summer wet spells become shorter over Scandinavia and northern Russia. The duration of dry spells decreases over Scandinavia and southern Europe in both winter and summer. For the discrimination between the roles of a changing number of wet days and of a regrouping of wet and dry days for the duration of the period, the authors suggest a fractional truncated geometric distribution. The changing numbers of wet days cannot explain the long-term variability in the duration of wet and dry periods. The observed changes are mainly due to the regrouping of wet and dry days. The tendencies in duration of wet and dry spells have been analyzed for a number of European areas. Over the Netherlands both wet and dry periods are extended in length during the cold and the warm season. A simultaneous shortening of wet and dry periods is found in southern Scandinavia in summer. Over France and central southern Europe during both winter and summer and over the Scandinavian Atlantic coast in summer, opposite tendencies in the duration of wet and dry spells were identified. Potential mechanisms that might be responsible for the changing durations of wet and dry periods and further perspectives are discussed. [ABSTRACT FROM AUTHOR]

Geographical zonality and continentality are presented. The global climate models (GCM) and the ERA-40 adjusted observations are called to answer three questions: (i.) How do these peculiarities appear in the observed climate of single meridional and zonal belts around the Globe? (ii.) Can the models properly simulate the present zonal and continental order in seasonal and annual means of temperature, precipitation and sea-level pressure? (iii.) Can these features also be recognised in patterns of CO2-forced climate changes? The questions are answered by using the MAGICC/SCENGEN 5.3v2 diagnostic model (Wigley, 2008). The third answer is based on the A1B emission scenario with no changes in the aerosol content. The simulated present climate patterns are compared to those from the ERA-40 reanalyses. The future time horizon is 2030-2049 compared to 1980-1999 for baseline climate. Zonality and continentality are presented in two narrow belts around the Globe. The pair of zonally oriented belts with 2.5 degree width, taken along both sides of the 47,5 N latitude, is selected to demonstrate the effects of continentality. These two neighbouring belts spread from the Pacific Ocean along North-America, the Atlantic Ocean, Europe and Asia. The other 2.5 degree wide belt starts at the North Pole, spreads along the 18.75th eastern longitude in its centre towards the South Pole, continuing along the 161.25th western longitude towards the North Pole, again. The first 180 degree long part of this belt crosses parts of Europe, Africa and Antarctica, whereas the rest spreads along the Pacific Ocean, is slightly disturbed in its purely oceanic character by Alaska. This belt is chosen to demonstrate zonality. The results indicate that various aspects of zonaliy and continentality occur in the simulation biases and projected changes, as well. [ABSTRACT FROM AUTHOR]

An extreme-value analysis of projected changes in heavy precipitation is carried out for an ensemble of eight high-resolution regional climate model simulations over the European domain. The consideration of several regional climate models that are forced by different global models allows for an assessment of the robustness of the results in terms of intersimulation agreement. The extreme-value statistical method is based on a model that includes time-dependent parameters. Summer and winter are examined separately. This allows for identifying and sharpening the understanding of physical processes inducing the changes in precipitation characteristics. Thermodynamic aspects of changes in heavy precipitation are discussed. Variables that are related to the process of precipitation formation, such as precipitable water and cloud liquid water, are examined. In this context, the scaling of changes in heavy precipitation and other thermodynamic quantities with changes in temperature is explored. The validity of a Clausius-Clapeyron scaling of heavy precipitation is assessed on regional scales. Significant regional and seasonal differences in trends of heavy precipitation and only a limited validity of the Clausius-Clapeyron scaling are found. In winter, enhanced moisture transport and storm-track intensity lead to an increase in heavy precipitation, especially over the northern parts of the European continent. In summer, the increase of precipitable water is less than that required to maintain the same probability for saturation over southern Europe, which results in negative trends of heavy precipitation in these regions. [ABSTRACT FROM AUTHOR]

Aim Climate is an important determinant of species distributions. We assess different aspects of risk arising from future climate change by quantifying changes in the spatial distribution of future climatic conditions compared with the recent past. Location Europe. Methods A 10′ × 10′ resolution gridded data set of five climate variables was used to calculate expected changes to the area, distance and direction of 1931–60 climatic conditions under the HadCM3 climate model for four future climate scenarios based on different rates of greenhouse gas emissions (SRES scenarios). Three levels of tolerance ranges determined the thresholds for which future conditions are considered analogous to 1931–60 (pre-warming) conditions. Results For many parts of Europe, areas with pre-warming analogous climate conditions will be smaller and further away in the future than they are now. For any location in Europe, areas with pre-warming analogous mean annual temperature conditions will, on average, be reduced between 23.7% (B1 scenario) and 49.7% (A1FI scenario) by 2100 when assuming a medium tolerance range. The mean distance to these areas will, on average, increase between 272 km (B1) and 645 km (A1FI). These changes are more pronounced for temperature than for water availability variables and also for narrow tolerance ranges compared to wide tolerance ranges. Using a combined measure of both temperature and precipitation variables, areas with prewarming analogous conditions are predicted to be in a more northeasterly direction in the future, but there are considerable regional differences within Europe. Main conclusions The results suggest that, for some parts of Europe, the loss of area with any suitable climatic conditions represents the greatest risk to biodiversity, but in other regions the distances that species may have to move to reach suitable climatic conditions may be a greater problem. Quantifying the distance and direction in analyses of change of climatically suitable areas can add additional information for climate change risk assessments. [ABSTRACT FROM AUTHOR]