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The article presents a method of optimizing the operation of an air heat pump. For this purpose, a genetic algorithm was used, whose task will be to start the heat pump at the moment of the highest outside air temperatures and the lowest charges for electric current. The device is used for the production of domestic hot water and heating water. Other heat sources such as water and soil were omitted from the analysis due to too much inertia and the fact that air heat pumps are the most widespread in Europe. The analysis focused on transition periods for the climate that occurs in the Polish. Energy calculations were carried out for the month of November 2021. The operation of the heat pump at the highest air temperatures during the day and at the lowest air temperatures during the night was compared. According to the analysis, the costs of generating heat at night are about 6% higher compared to the production of heat during the day. The analysis took into account the occurrence of the largest partitions of hot water from the buffer. The proposed solution for optimizing the operation of the heat pump based on the use of a genetic algorithm takes into account, m.in, the analysis of daily water partitions from the buffer, the purpose of the installation, historical weather data from a given climate zone, maintaining the minimum water temperature in the buffer, periodic overheating above 75°C and electricity prices related to the applicable energy tariff. [ABSTRACT FROM AUTHOR]

[Display omitted] • The model performs good in capturing the seasonal pattern and peak values of river water temperature. • Air temperature and day of year are the major factorson modeling river water temperature. • The model is a promising tool to investigate the impact of climate change on river thermal dynamics. Water temperature is an important physical indicator of rivers because it impacts many other physical and biogeochemical processes and controls the metabolism of aquatic species in rivers. Having a good knowledge of river thermal dynamics is of great importance. In this study, an advanced machine learning based model that is fast, accurate and easy to use, namely the nonlinear autoregressive network with exogenous inputs (NARX) neural network, was coupled with Bayesian Optimization (BO) algorithm for optimizing the number of NARX hidden nodes and lagged input/target values and the Bayesian Regularization (BR) backpropagation algorithm for the NARX training, to forecast daily river water temperatures (RWT). Long-term observed data from 18 rivers of the Vistula River Basin, one of the largest rivers in Europe, were used for model testing, and model performance was compared with the air2stream model. The results showed that the NARX-based model performs significantly better than the air2stream model in the calibration and validation stages, and can better capture the seasonal pattern and peak values of RWT. Input combinations impact the performance of the NARX-based model in RWT modeling, and air temperature and the day of the year (DOY) are the major inputs, while streamflow and rainfall play a minor role on modeling RWT at the Vistula River Basin. Considering that future times series of air temperatures are easily accessible from climate models and DOY is easy to be considered in the model, the NARX-based model can serve as a promising tool to investigate the impact of climate change on river thermal dynamics. [ABSTRACT FROM AUTHOR]

Climate simulations consistently show an increase in European near-surface air temperature by the late 21st century, although projections for near-surface wind speeds and irradiance differ between models, and are accompanied by large natural variability. These factors make it difficult to estimate the effects of physical climate change on power system planning. Here, the impact of climate change on future European power systems is estimated. We show for the first time how a set of divergent future power system scenarios lead to marked differences in Europe's total energy balance (demand-net-renewable supply) by 2050, which dominate over the uncertainty associated with climate change (∼50% and ∼5% respectively). However, within any given power system scenario, national power systems may be subject to considerable impacts from climate change, particularly for seasonal differences between renewable resources (e.g., wind power may be impacted by ∼20% or more). There is little agreement between climate models in terms of the spatio-temporal pattern of these impacts, and even in the direction of change for wind and solar. More thorough consideration of climate uncertainty is therefore needed, as it is likely to be of great importance for robust future power system planning and design. • Future climate affects European power systems simulated with EURO-CORDEX models. • Significant climate uncertainty in key power system properties (demand, renewables). • Climate uncertainty exacerbated in renewable-intensive power system scenarios. • Spatio-temporal and multi-model aggregation masks complex patterns of change. • Better understanding of climate uncertainty in power system design is needed. [ABSTRACT FROM AUTHOR]

Europe has experienced many extreme heat waves over the past few decades. In this study, the physical processes underlying these long-lasting and wide-ranging heat wave events are investigated based on a case study in Europe in June 2021. Heat waves are associated with barotropic anticyclonic anomalies accompanied by positive geopotential height anomalies locally. These anomalies persist under the conditions of increased meridional air temperature gradients of the mid–upper troposphere in the high latitudes of Eurasia and the formation of the Arctic front jet. The shrinking high-latitude snow cover in April–May favors higher surface temperatures and larger meridional temperature gradients in June in the mid–upper troposphere due to the soil moisture–evaporation–temperature positive feedback process. The summer Arctic front jet is then strengthened, and the mid-latitude westerly winds are weakened. This atmospheric circulation background favors waveguide formation and wave resonance that produces high-amplitude atmospheric waves and the stagnation of ridges in the mid-latitudes. Numerical experiments using the Community Atmosphere Model version 5 verify the proposed physical mechanisms, with the climatic responses in sensitivity experiments to anomalous snowfall rates closely resembling the observational results. Therefore, in June 2021, under the identified atmospheric circulation background and the perturbation of the upstream positive phase of the North Atlantic Oscillation, the large-scale barotropic high pressure and barotropic anticyclonic circulation in the study region tended to be stable and persistent, which is favorable for the production of long-lasting and wide-ranging heat wave events. • Physical mechanisms underlying heat waves are investigated based on a case study in Europe in June 2021. • Shrinking Eurasian snow cover in spring favors the strengthened summer Arctic front jet that produces high-amplitude waves. • Upstream positive NAO in June 2021 favors a sequence of waves downstream and affect persistent anticyclone for heat waves. [ABSTRACT FROM AUTHOR]

• Throughout the year, urban forest edges are warmer and drier compared to forest interiors. • Warm and dry microclimates are present up to large edge distances in urban forests. • A denser forest structure buffers the microclimate irrespective of edge distance. • Maintaining dense canopies in wide edge zones can enhance microclimate buffering. The urban heat island (UHI) causes strong warming of cities and their urban forests worldwide. Especially urban forest edges are strongly exposed to the UHI effect, which could impact urban forest biodiversity and functioning. However, it is not known to what extent the UHI effect alters edge-to-interior microclimatic gradients within urban forests and whether this depends on the forests' structure. Here we quantified gradients of air temperature, relative air humidity and vapour pressure deficits (VPD) along urban forest edge-to-interior transects with contrasting stand structures in six major cities across Europe. We performed continuous hourly microclimate measurements for two consecutive years and analysed the magnitude and depth of edge effects, as well as forest structural drivers of microclimatic variation. Compared to edge studies in rural temperate forests, we found that edge effects reached deeper into urban forests, at least up to 50 m. Throughout the year, urban forest edges were warmer and drier compared to forest interiors, with the largest differences occurring during summer and daytime. Not only maximum, but also mean and minimum temperatures were higher at the urban forest edge up to large edge distances (at least 85 m). Denser forests with a higher plant area index buffered high air temperatures and VPDs from spring to autumn. We conclude that urban forest edges are unique ecotones with specific microclimates shaped by the UHI effect. Both forest edges and interiors showed increased buffering capacities with higher forest canopy density. We advocate for the conservation and expansion of urban forests which can buffer increasingly frequent and intense climate extremes. To this end, urban forest managers are encouraged to aim for multi-layered dense forest canopies and consider edge buffer zones of at least 50 m wide. [Display omitted] [ABSTRACT FROM AUTHOR]

• The influence of decay was much stronger than the influence of climatic variables. • Damage degree explained about 85% of the variation in Rotfinder values. • Rotfinder is applicable on single trees, with two opposite measurements only. • A maximum threshold value of about 11000 RU was identified for decay detection. Wood decay limits the function of Norway spruce (Picea abies (L.) H.Karst.) for wood production and in protection forests (i.e. forests protecting against natural hazards). Therefore, more detailed knowledge about the presence and extent of decay in living trees is highly relevant for both the timber industry and risk management strategies. However, decay detection in living Norway spruce trees is not sufficiently possible by visual methods. One possibility to overcome this problem are indirect, non- or least-destructive measurement devices such as the decay detector Rotfinder. Yet, the influence of climatic variables on the reliability of decay detection determined with the Rotfinder is not sufficiently known. Therefore, we assessed the influences of several climatic variables on the Rotfinder values continuously over one year at the same measuring position. Additionally, we determined a threshold value for decay detection in single Norway spruce trees in Central Europe. Regardless of the temperature, Rotfinder values measured over one year were mainly influenced by internal decay status, i.e. damage degree, which explained about 85% of the variation based on a generalized linear mixed effects model in this temperature range (about 6–27 °C). Together with fluctuations in air temperature, about 87% of the variation in Rotfinder values could be accounted for. For decay detection in single Norway spruce trees, a maximum threshold value of about 11,000 Rotfinder units (RU) was identified, equivalent to about 36% of the Rotfinder values measured for intact trees. Our results indicate that the Rotfinder can be used successfully for decay detection in single Norway spruce trees under Central European conditions. [ABSTRACT FROM AUTHOR]

Highlights • Seasonal evaluation of precipitation characteristics based on aggregated indices. • Trend towards drier springs within Central Europe (Germany > Czechia > Poland). • Restricted temporal stability of trends (drought trends for 1961–2015 > 1951–2015). • Trends influenced by temperature increase (trends of water balance > precipitation). • Heavy precipitation increases prevail throughout all seasons. Abstract The relevance of drought is still often underestimated for temperate climate regions like Central Europe that are characterized by on average ample precipitation. Nonetheless, several drought events in recent years (e.g. 1992, 2003, 2015 and 2018) demonstrated that droughts are a relevant factor for several economic activities (e.g., agriculture, water dependent industries, energy supply, etc.) in Central Europe. This is particularly true for the vegetation period, where increasing evapotranspiration rates due to rising atmospheric temperatures are intensifying existing drought conditions that originally developed from rainfalls deficits. The contribution of this study is an assessment of the long-term variability of drought conditions and seasonal climate trends within 1951–2015 based on a collective of 91 climate stations from the national meteorological services of Germany, Poland and the Czech Republic. Using a set of eight drought and three heavy precipitation indices an aggregated evaluation of seasonal precipitation characteristics is done and the driest seasons are identified for the entire study area as well as for four sub-regions. It is shown that the choice of the study period matters (1951–2015 vs. 1961–2015) as the pronounced (multi-)decadal variability of drought conditions restricts the temporal stability of computed trends. The drought trends computed for 1951–2015 are similar in direction, but generally smaller in magnitude than those of the ten year shorter period 1961–2015, as the 1950s have been a very dry decade in Central Europe. Seasonally, drying trends were observed for spring and less pronounced for summer, while autumn and winter show wetting trends. The seasonal trends are sensitive to shifts in the season definition by one month. Vegetation period I (VP-I) shows stronger drying trends, but less increases in heavy precipitation than spring, while the drought trends are less pronounced in vegetation period II (VP-II) as compared to the summer season, but more trends towards heavy precipitation increases occur in VP-II. These differences are explained by the daily trends in the seasonal cycle that show the strongest drying in April, June and the beginning of August and the strongest wetting in March and September. Generally, heavy precipitation increases prevail over decreasing trends in all seasons, whereby stations with strong drought trends generally have smaller positive or even negative heavy precipitation trends. A simultaneous occurrence of drought and heavy precipitation increases is observed in spring at several stations, particularly in sub-region West. Graphical abstract Image, graphical abstract [ABSTRACT FROM AUTHOR]

Cyclic volatile methylsiloxanes (cVMS) and short-chain chlorinated paraffins (SCCPs) use has been restricted in recent years due to environmental health concerns. Both of these classes of emerging contaminants possess long range transport potential (LRTP), highlighting the need for continuous monitoring to assess effectiveness of implemented regulations. However, emission source elucidation and understanding processes affecting atmospheric transport remain challenging. Atmospheric levels of cVMSs and SCCPs were simultaneously monitored at a background monitoring site in Norway from January–July 2020. Concentrations obtained from active air samplers ranged from 49.9 to 845 (mean: 208) pg/m3 for ƩSCCPs and from 0.4 to 3.5 (mean: 1.5), 1.1–15 (mean: 5.6) and 0.1–0.9 (mean: 0.4) ng/m3 for octamethylcyclotetrasiloxane (D4), decamethylcyclopentasiloxane (D5) and dodecamethylcyclohexasiloxane (D6), respectively. As SCCPs pose several challenges to analysts, different quantification methodologies and blank handling procedures were investigated to ensure reliable environmental measurements. Simulations using a Lagrangian atmospheric transport model (FLEXPART) revealed air masses impacting sampling measurements were of Oceanic origin, but periodic emission events from Europe and Russia were also observed. Seasonal pattern in cVMS concentrations was mainly driven by atmospheric degradation via hydroxyl radical reaction, whereas SCCP concentrations were more influenced by periodic anthropogenic inputs from local and continental Europe. No clear correlation could be observed with SCCP atmospheric concentrations and temperature over the entire sampling campaign. However, increased volatilization at elevated temperatures may be important with emissions originating from local sources. Higher chlorinated homologue groups dominated during the winter season and declined towards spring and summer, whereas reverse was found for the lower and more volatile chlorinated homologue groups. [Display omitted] • LRT of cVMS primarily driven by seasonal atmospheric degradation. • SCCP LRT primarily driven by anthropogenic inputs from continental Europe. • Seasonal changes in SCCP composition pattern were observed. • Proper quantification and blank handling procedures crucial for reporting SCCP. [ABSTRACT FROM AUTHOR]

The main goal of this paper is to derive a method for a daily gross primary production (GPP) product over Europe and Africa taking the full advantage of the SEVIRI/MSG satellite products from the European Organization for the Exploitation of Meteorological Satellites (EUMETSAT) sensors delivered from the Satellite Application Facility for Land Surface Analysis (LSA SAF) system. Special attention is paid to model the daily GPP response from an optimized Montheith's light use efficiency model under dry conditions by controlling water shortage limitations from the actual evapotranspiration and the potential evapotranspiration (PET). The PET was parameterized using the mean daily air temperature at 2 m ( T a ) from ERA-Interim data. The GPP product (MSG GPP) was produced for 2012 and assessed by direct site-level comparison with GPP from eddy covariance data (EC GPP). MSG GPP presents relative bias errors lower than 40% for the most forest vegetation types with a high agreement ( r > 0.7) when compared with EC GPP. For drylands, MSG GPP reproduces the seasonal variations related to water limitation in a good agreement with site level GPP estimates (RMSE = 2.11 g m −2 day −1 ; MBE = −0.63 g m −2 day −1 ), especially for the dry season. A consistency analysis against other GPP satellite products (MOD17A2 and FLUXCOM) reveals a high consistency among products (RMSD < 1.5 g m −2 day −1 ) over Europe, North and South Africa. The major GPP disagreement arises over moist biomes in central Africa (RMSD > 3.0 g m −2 day −1 ) and over dry biomes with MSG GPP estimates lower than FLUXCOM (MBD up to −3.0 g m −2 day −1 ). This newly derived product has the potential for analysing spatial patterns and temporal dynamics of GPP at the MSG spatial resolutions on a daily basis allowing to better capture the GPP dynamics and magnitude. [ABSTRACT FROM AUTHOR]

The aim of this paper is to present the development and evaluation of neural network based identification algorithms for the prediction of outdoor air temperature using acquired data from four European cities (Ancona – Italy, Chania – Greece, Granada – Spain and Mollet – Spain). Different neural network topologies (feed forward, cascade and elman) have been tested to identify the most suitable for each city. The efficiency of the prediction is validated by comparing predicted and measured outdoor air temperature. Furthermore, statistical tools such as R 2 , and root mean square error (rmse) are used to evaluate the annual performance of the neural network. The comparison of measured and predicted outdoor air temperature ( R 2 > 0.9, rmse <2 °C) confirms the accurate training of the neural network for all four European cities. All work has been contacted using Matlab's environment. [ABSTRACT FROM AUTHOR]

• Alley cropping systems show reduced wind speed, light intensity and surface runoff. • Effect on other parameters varies with the design and orientation of the tree rows. • Soil moisture showed the highest variability within and among studies. Climate change scenarios predict an increased occurrence of droughts and heatwaves, as well as extreme rainfall events in Central Europe. Alley cropping, which is the inclusion of rows of trees and shrubs in agricultural land, could enhance the resilience of cropping systems, as these systems are expected to positively modify the microclimate and water balance of croplands. This review analyses the effect of alley cropping on the microclimate and water balance, based on the available evidence from temperate alley cropping systems. Within alley cropping systems, the tree rows generate gradients in microclimatic variables, whereby strongest effects are observed in or close to the tree rows. Field-scale studies on light intensity (n =20), wind speed (n =4) and surface runoff (n =3) all reported a reduction compared to sole cropping systems. Effects on air temperature (n =10), relative humidity (n =5) and evapotranspiration (n =6) varied among studies, with the majority reporting a decrease in daytime temperatures (50% of studies), variable effects on relative humidity (60%) and an increase in evapotranspiration (50%) due to higher evapotranspiration by trees. Highest variation among studies was found for soil moisture, with 41% of studies reporting temporal and spatial differences within the system. This variation among studies likely depends on the purpose of the trees (short rotation coppice vs. fruit and/or timber trees) and design of the system. Also site context, such as topography, landscape diversity and climate, could play a role, but these factors are rarely taken into account. Only few studies investigated landscape-scale effects (n =3), such as groundwater recharge and moisture recycling. Future research should investigate the role of site context in the functioning of alley cropping systems and quantify landscape-scale effects. The process understanding gained from those studies will contribute to designing alley cropping systems that enhance the climate change resilience of current central European cropping systems. [Display omitted] [ABSTRACT FROM AUTHOR]

The impact of biogenic emissions on ozone and PM 2.5 levels over Europe is assessed using CMAQ. Biogenic emissions are predicted to increase Max8hrO 3 mixing ratios by 5.7% and to decrease PM 2.5 concentrations by 1.9%, increasing PM 2.5 _ OC by 13.6% and decreasing PM 2 . 5 _SO 4 , PM 2 . 5 _NO 3 and PM 2 . 5 _NH 4 by 5.6%, 3.7% and 5.6%, respectively, on average over Europe due to their interactions with anthropogenic emissions. A suite of perturbations in temperature is imposed individually on the base case conditions in order to determine the sensitivities to air temperature changes. Temperature increases of 1, 2 or 3° K suggest an average increase in Max8hrO 3 mixing ratios of 0.9%, 1.8% or 2.9%, respectively, and an average decrease in daily average PM 2.5 concentrations of 2.5%, 4.2% and 5.8%, respectively, increasing PM 2.5 _ OC and decreasing PM 2 . 5 _SO 4 , PM 2 . 5 _NO 3 and PM 2 . 5 _NH 4 component concentrations on average over Europe. In order to examine if abatement measures for anthropogenic emissions could offset ozone increases in higher temperatures and their effect on PM 2.5 concentrations, a simulation with a domain wide reduction in anthropogenic NO x emissions of 10% is performed. This is estimated to reduce Max8hrO 3 mixing ratios by 1.3% on average over Europe. However, NO x reduction is estimated to increase Max8hrO 3 in VOCs limited areas. The reduction in anthropogenic NO x emissions is predicted to reduce PM 2.5 concentrations by 1.0% enhancing the reduction simulated, here, with temperature increase but further modifying PM 2.5 component concentrations. [ABSTRACT FROM AUTHOR]

The Pyhäsalmi mine, central Finland, has operated as a deep metal mine since 1967. It currently reaches a depth of almost 1500 m, making it the deepest mining operation in Europe. Around 900,000 m 3 of metal-rich, extremely acidic water are pumped out of the mine each year. The near constant air temperature of ∼24 °C together with exposure of sulfidic rock surfaces to air and water, have created an environment that is highly suitable for colonization by acidophilic mineral-oxidizing microorganisms. Using a combined cultivation-dependent and molecular approach, indigenous bacteria in waters at two depths within the mine, and of an acid streamer sample were identified and isolated. Iron-oxidizing chemolithotrophs ( Acidithiobacillus and Leptospirillum spp., and “ Ferrovum myxofaciens ” were the most abundant bacteria in mine water samples, whereas the acid streamer community contained a greater proportion of heterotrophic acidophiles ( Ferrimicrobium acidiphilum and a gammaproteobacterium related to Metallibacterium scheffleri ). The most abundant isolates obtained from both water and streamer samples were all strains of Acidithiobacillus Group IV, a proposed separate species of iron-oxidizing acidithiobacilli that has not yet been classified as such. Archaea were also detected in water and streamer samples using molecular methods, but most were not identified and no isolates were obtained. [ABSTRACT FROM AUTHOR]

Abstract: Mitigating climate change through operational energy reduction in existing buildings is of highest priority for policy-makers in Europe and elsewhere. At the same time there is increasing understanding of the significance of impacts arising from material production for buildings. The aim of this work has therefore been to evaluate the importance of embodied GWP for refurbishment for operational energy reduction on a stockwide basis. It is further intended to judge the relative significance of embodied GWP for specific refurbishment measures implemented for operational energy reduction. We study the case of operational energy reduction in the Swedish residential building stock by 50% compared to 1995. The total embodied GWP to achieve the noted operational energy reduction is 0.35 Mt CO2-e/year. 83% of this total is due to ventilation and window measures alone. Compared with previous studies assessing GWP mitigation from operational energy reduction, the “GWP payback time” is just over 3 years. Many types of measure that contribute significantly to achieving the above operational energy goal had average embodied GWP between 10 and 20 g CO2-e/kW h operational energy reduction, notably window and ventilation measures. Indoor temperature reduction (to 20 °C), was also significant for stockwide operational energy reduction but had a very low GWP of 0.4 g CO2-e/kW h operational energy reduction. If this measure proves unfeasible to implement on a stockwide basis then more expensive measures with higher embodied GWP will be needed to achieve the stated energy reduction goal. [Copyright &y& Elsevier]

Highlights: [ • ] Soil samples represented a range of pedo-climatic conditions, across Europe. [•] Pre-incubation temperatures were tested for soil basal respiration. [ • ] Pre-incubation conditions did not affect initial rate of basal respiration. [ • ] Experimental incubation temperatures were evaluated for soil basal respiration. [•] Results were most consistent at experimental incubation temp of 20°C and 25°C. [Copyright &y& Elsevier]

This study presents a proxy-based, quantitative reconstruction of cold-season (mean October to May, TOct–May) air temperatures covering nearly the entire last millennium (AD 1060–2003, some hiatuses). The reconstruction was based on subfossil chrysophyte stomatocyst remains in the varved sediments of high-Alpine Lake Silvaplana, eastern Swiss Alps (46°27’N, 9°48′W, 1791 m a.s.l.). Previous studies have demonstrated the reliability of this proxy by comparison to meteorological data. Cold-season air temperatures could therefore be reconstructed quantitatively, at a high resolution (5-yr) and with high chronological accuracy. Spatial correlation analysis suggests that the reconstruction reflects cold season climate variability over the high- Alpine region and substantial parts of central and western Europe. Cold-season temperatures were characterized by a relatively stable first part of the millennium until AD 1440 (2σ of 5-yr mean values = 0.7 °C) and highly variable TOct–May after that (AD 1440–1900, 2σ of 5-yr mean values = 1.3 °C). Recent decades (AD, 1991-present) were unusually warm in the context of the last millennium (exceeding the 2σ-range of the mean decadal TOct–May) but this warmth was not unprecedented. The coolest decades occurred from AD 1510–1520 and AD 1880–1890. The timing of extremely warm and cold decades is generally in good agreement with documentary data representing Switzerland and central European lowlands. The transition from relatively stable to highly variable TOct–May coincided with large changes in atmospheric circulation patterns in the North Atlantic region. Comparison of reconstructed cold season temperatures to the North Atlantic Oscillation index (NAO) during the past 1000 years showed that the relatively stable and warm conditions at the study site until AD 1440 coincided with a persistent positive mode of the NAO. We propose that the transition to large TOct–May variability around AD 1440 was linked to the subsequent absence of this persistent zonal flow pattern, which would allow other climatic drivers to gain importance in the study area. From AD 1440–1900, the similarity of reconstructed TOct–May to reconstructed air pressure in the Siberian High suggests a relatively strong influence of continental anticyclonic systems on Alpine cold season climate parameters during periods when westerly airflow was subdued. A more continental type of atmospheric circulation thus seems to be characteristic for the Little Ice Age in Europe. Comparison of Toct–May to summer temperature reconstructions from the same study site shows that, as expected, summer and cold season temperature trends and variability differed completely throughout nearly the entire last 1000 years. Since AD 1980, however, summer and cold season temperatures show a simultaneous, strong increase, which is unprecedented in the context of the last millennium. We suggest that the most likely explanation for this recent trend is anthropogenic greenhouse gas (GHG) forcing. [ABSTRACT FROM AUTHOR]

• Fire intensity and air temperature have a great influence on scorch height. • The presence of canopy gaps results in scorch height differences. • The scorch height increases because of the canopy gaps in the upper slope. • The scorch volume varies based on fire intensity, air temperature and canopy base height. • The scorch height and volume play an important role in prescribed burn windows. The use of prescribed fire has been on the rise in recent years owing to its effectiveness in surface fuel reduction, its implementation cost, and the possibility of firefighter training. However, greater knowledge regarding the effects of fire on woodlands is required by forest managers. Scorch height and scorch volume are the most widely used variables for evaluating the effects of burning on trees. This study proposes a scorch height model for the prescribed fires of pine stands in Southern Europe. Although the two main variables of the existing models (fire-line intensity and air temperature) were considered, our model achieved a coefficient of determination of 89% with the incorporation of the canopy base height. A decision tree for scorch volume was also developed using the three independent variables. The presence of canopy gaps in the lower, mid-, and upper slopes resulted in significant differences in the scorch height. The scorch height increased between 0.33 m and 2.08 m because of the canopy gaps in the upper slope. These findings can play an important role in the implementation and improvement of prescribed burn windows. [ABSTRACT FROM AUTHOR]

Abstract: The decomposition of soil organic matter (SOM) is temperature dependent, but its response to a future warmer climate remains equivocal. Enhanced rates of decomposition of SOM under increased global temperatures might cause higher CO2 emissions to the atmosphere, and could therefore constitute a strong positive feedback. The magnitude of this feedback however remains poorly understood, primarily because of the difficulty in quantifying the temperature sensitivity of stored, recalcitrant carbon that comprises the bulk (>90%) of SOM in most soils. In this study we investigated the effects of climatic conditions on soil carbon dynamics using the attenuation of the 14C ‘bomb’ pulse as recorded in selected modern European speleothems. These new data were combined with published results to further examine soil carbon dynamics, and to explore the sensitivity of labile and recalcitrant organic matter decomposition to different climatic conditions. Temporal changes in 14C activity inferred from each speleothem was modelled using a three pool soil carbon inverse model (applying a Monte Carlo method) to constrain soil carbon turnover rates at each site. Speleothems from sites that are characterised by semi-arid conditions, sparse vegetation, thin soil cover and high mean annual air temperatures (MAATs), exhibit weak attenuation of atmospheric 14C ‘bomb’ peak (a low damping effect, D in the range: 55–77%) and low modelled mean respired carbon ages (MRCA), indicating that decomposition is dominated by young, recently fixed soil carbon. By contrast, humid and high MAAT sites that are characterised by a thick soil cover and dense, well developed vegetation, display the highest damping effect (D =c. 90%), and the highest MRCA values (in the range from 350±126 years to 571±128 years). This suggests that carbon incorporated into these stalagmites originates predominantly from decomposition of old, recalcitrant organic matter. SOM turnover rates cannot be ascribed to a single climate variable, e.g. (MAAT) but instead reflect a complex interplay of climate (e.g. MAAT and moisture budget) and vegetation development. [Copyright &y& Elsevier]

Abstract: This study focuses on the changes in the yield stability of winter wheat and spring barley over the past 140 years and changes in the weather–yield relationships. The study area is located in the Czech Republic in eastern Central Europe between 48°37′–49°30′N and 15°29′–17°55′E and includes 4900km2 of arable land within eight districts for which yield data were collected for the years 1869–1913 and 1961–2007. The cropping systems in the region are dominated by rain-fed production of winter wheat, spring barley and winter rape. The yields for winter wheat and spring barley have increased by a factor of 2–3 since the late 19th century, whereas the temperature and precipitation patterns showed trends toward warmer and drier conditions. There was a considerable increase in the inter-annual variability of the absolute yields in the districts. When the variability was evaluated in relative terms (i.e., compared with the yield level), it showed no change or insignificant increases in the warmest and driest regions. The study also found that the sensitivity to inter-seasonal temperature increase was much more pronounced during 1961–2007 than at the end of the 19th century and that an increase of the mean temperature by 1°C led to yield decreases of up to 11% for winter wheat and up to 10% for spring barley. In contrast, the same temperature increase during the 1869–1913 period would have caused yield decreases of up to 8% and 5%, respectively. In the 1961–2007 period, the negative relationship between the temperature and yields of barley (wheat) was highly significant in seven (eight) of eight districts compared with only four (five) with a much weaker correlation in 1869–1913. During the early period, drier conditions had very small negative or even slightly positive effects on yields, whereas at the end of the 20th century, the May and June drought became a factor that explained a considerable proportion of the yield variability. This was the case especially for spring barley, which is more vulnerable to droughts than is winter wheat. The negative effects of increasing temperature and drought on grain yield were most pronounced in the districts that are currently the warmest and driest. The increasing vulnerability of wheat and barley production to increasing temperatures and droughts over time should be addressed by plant breeders, as there are relatively few adaptation options available to farmers except switching to other crops, which cannot fully substitute for wheat and barley. [Copyright &y& Elsevier]

Abstract: Seasonal snow cover is a valuable indicator of climatic variations due to its sensitivity to temperature and precipitation. Complementary to ground-based station data, satellite time series provide large-scale spatial capabilities. The primary disadvantage of this technique, however, is the relative brevity of records. Only AVHRR offers the opportunity to analyze more than 25years of medium-resolution satellite imagery on a daily basis. AVHRR thereby holds a great potential to detect, map and quantify long-term environmental changes. However, to serve this purpose though, adequate algorithms and careful validation are of major significance. Here, we describe and extensively validate snow cover retrieval from historical 1-km AVHRR data using a stable snow detection algorithm, which allows consistent snow sampling across all AVHRR sensors. As a new asset, a pixel-wise probability map based on logistic regression is provided for each snow mask. The spatial and seasonal validation includes a comparison to MOD10A1 and webcam imagery. In addition, the influence of acquisition geometry and the sensor-to-sensor consistency have been investigated using LANDSAT TM data and a snow climatology based on long-term station data. We conclude that the snow detection algorithm tested allows for a 1-km snow extent climatology to be generated from the 25-year full-resolution AVHRR data archived at the University of Bern with favorable accuracy and stability. Given the importance of mountainous regions for climate change studies, this satellite-based data set could become an important tool for assessing environmental changes in the European Alps. [Copyright &y& Elsevier]

Abstract: This report presents a study of the variability in a recently published April to September gridded reconstruction temperatures in Europe and an analysis of their extremes. This reconstruction was based on tree rings, historical documents, pollen assemblages and ice cores. The methodology used, an original spectral analog method, preserves long-term variations and the variability of temperature series, which guarantees the pertinence of the analysis of the extremes over a period as long as the last millennium. The analysis of the extremes was performed with the peak-over-threshold (POT) method over two warm periods (A.D. 1000–1350 and 1880–2007) and a cold period (A.D. 1350–1950). We found that (1) according to the long-term variations shown in this reconstruction, the growing season temperature during the last decade has exceeded all of those observed during the Medieval period; (2) the return period of the maximum event of the Medieval period has been reduced by at least a factor of 5; and (3) all decades before A.D. 1350 were warm on average but relatively heterogeneous, while the last decade was homogeneously warmer. A new result of this study concerning Europe is that this anthropogenic change is characterized by spatial homogeneity, with similar changes in both average temperatures and in the distribution of extreme events, while natural climate forcings induce warm periods with heterogeneous spatial patterns and less frequent extreme events. [Copyright &y& Elsevier]

Abstract: A 274-lake calibration data-set for chironomid-based temperature reconstruction is presented which is based on the taxonomic amalgamation of a 117-lake data-set from Switzerland and a 157-lake data-set from Norway and Svalbard. Taxonomic consistency of the two data-sets was ensured by joint microscope sessions by the two involved analysts, re-identifying chironomid assemblages in the Swiss data-set to reach an identical taxonomic resolution as in the Norwegian data, and by double-checking selected samples of the Norwegian calibration data-set. The combined Swiss-Norwegian calibration data-set contains information on the distribution of 154 chironomid taxa over a July air temperature range of 3.5–18.4 °C, a pH range of 4.7–8.8, and an altitudinal range of 5–2815 masl from lakes in temperate, subarctic, arctic, and alpine environments. Inference models developed based on this data-set using weighted averaging-partial least squares (WA-PLS) regression outperformed inference models based on maximum likelihood regression. After outlier deletion WA-PLS regression predicted July air temperature with a bootstrapped (cross-validated) root mean squared error of prediction (RMSEP) of 1.40 °C. Inference models developed from the separate regional data-sets have an RMSEP of 1.16 and 1.43 °C for the Norwegian and the Swiss calibration data-set, respectively. The WA-PLS inference model based on the Norwegian data-set adequately predicted July air temperature based on chironomid assemblages in the Swiss data-set (RMSEP 2.05 °C; r 2 0.74). In contrast, the WA-PLS model based on the Swiss chironomid assemblages performed poorly in inferring July air temperatures based on the Norwegian chironomid assemblages (RMSEP 2.70 °C; r 2 0.39). We attribute this discrepancy to the large proportion of chironomid taxa in Norwegian samples not represented in the Swiss data-set, the larger range of both pH and lake types included in the Norwegian calibration data-set, and the lack of some chironomid taxa with an arctic and boreal distribution in the Swiss data-set. The WA-PLS inference model based on the combined Swiss-Norwegian calibration data-set is the largest taxonomically consistent chironomid-based inference model available to date and outperforms other existing models if the r 2 and RMSEP relative to the overall temperature gradient are examined. We demonstrate that the combined model can reconstruct a larger range of temperatures when applied to fossil assemblages than models based on the Norwegian or Swiss calibration data-sets only. The combined data-set includes the majority of chironomid taxa expected in late Pleistocene and Holocene sediments of lakes from Northern, Eastern, and Central Europe as well as from southern European mountain lakes. The newly developed WA-PLS inference model is therefore well suited for developing continental-scale reconstructions of late Quaternary temperature change based on chironomid records from different parts of Europe. [Copyright &y& Elsevier]

Abstract: In this study, we apply for the first time the definition of a derecho (Johns and Hirt, 1987) to European cold-season convective storm systems. These occurred on 18 January 2007 and 1 March 2008, respectively, and they are shown to fulfill the criteria of a derecho. Damaging winds were reported over a distance of 1500km and locally reached F3 intensity. Synoptic analysis for the events reveal strongly forced situations that have been described for cold-season derechoes in the United States. A comparison of swaths of damaging winds, radar structures, detected lightning, cold pool development, and cloud-top temperatures indicates that both derechoes formed along cold fronts that were affected by strong quasi-geostrophic forcing. It seems that the overlap of the cold front position with the strong differential cyclonic vorticity advection at the cyclonic flank of mid-level jet streaks favoured intense convection and high winds. The movement and path width of the two derechoes seemed to be related to this overlap. The wind gust intensity that was also different for both events is discussed and could be related to the component of the mid-level winds perpendicular to the gust fronts. [Copyright &y& Elsevier]

Abstract: Summer 2007 was abnormally warm for many areas of southeastern Europe, the Balkan peninsula and parts of Asia Minor with departures from the seasonal means exceeding 4 °C in some areas but also distinct periods of extremely hot weather. Greece experienced very likely the warmest summer of its instrumental history with record breaking temperatures being observed at a number of stations. The historical air temperature record of the National Observatory of Athens (NOA), extending back to the 19th century, was used in order to highlight the rarity of the event. Seasonal (June to August) temperature anomalies at NOA exceeded 3 °C corresponding to more than 3 standard deviations with respect to the 1961–1990 reference period. The record value of 44.8 °C was observed at NOA on 26 June 2007 (previous record 43 °C in June 1916) during the first and most intense heat wave that affected the area. The study places summer 2007 in the climatology of the previous century and also examines whether the statistics of summer 2007 have similarities with Mediterranean summers of the future. An ensemble of regional climate model simulations undertaken for the European domain indicate that summer 2007 reflects the daily maximum temperatures that are projected to occur in the latter part of the 21st century. The analysis of temperature data from other less urbanized stations indicates that the urban heat effect in Athens contributed positively to the anomalies of the nocturnal temperatures. The abnormally hot summer of 2007 is perhaps not the proof but a strong indicator of what eastern Mediterranean summers could resemble in future. [Copyright &y& Elsevier]

Regional and temporal growth variation of Norway spruce (Picea abies (L.) Karst.) and its dependence on air temperature and precipitation were compared in stands across latitudinal and altitudinal transects in southwestern and eastern Germany, Norway, and Finland. The temporal variation of radial growth was divided into two components: medium- and high-frequency variation, i.e. decadal and year-to-year variation, respectively. The medium-frequency component was rather different between regions, especially the southern and northern ones. However, within each region the medium-frequency growth variation was relatively similar, irrespective of altitudinal and latitudinal differences of the sample sites. A part of the high-frequency variation was common to all four regions, which suggests that some factors synchronising tree growth are common for the entire study area. The high-frequency component of growth was more strongly related to monthly air temperature and precipitation than was the medium-frequency variation. The limiting effect of low temperatures was more significant at northern as well as high-altitude sites, while the importance of precipitation increased in the south and at low altitudes. [Copyright &y& Elsevier]

There is a sparsity of long, continuous palaeotemperature records for the last glacial period in central Europe, particularly for the interval corresponding to Marine Isotope Stages (MIS) 4 and 3. Here we present a new, ca. 50-thousand year (ka)-long chironomid record from Füramoos, southern Germany, covering the interval from MIS 5a to MIS 3 that we use to examine lake development and then to quantitatively reconstruct mean July air temperatures. Chironomid assemblages with high abundances of taxa such as Polypedilum nubeculosu m-type, Microtendipes pedellus -type, Cladopelma lateralis -type and Dicrotendipes nervosus -type imply a shallow-lake setting for the majority of the examined interval, which is corroborated by other aquatic remains such as oribatid mites, Sialidae and Ceratopogonidae. Assemblages from the interval ca. 99 to 80 ka (in the region corresponding to the Brörup Interstadial, Stadial B and early Odderade Interstadial) are dominated by taxa such as Tanytarsus glabrescens -type and Tanytarsus mendax -type and indicate relatively warm temperatures. Assemblages from the interval covering ca. 80 to 54 ka (corresponding to the late Odderade, Stadial C, Dürnten Interstadial and Stadial D) are dominated by taxa such as Sergentia coracina -type and Tanytarsus lugens -type and are typical for cooler conditions. Reconstructed July temperatures for the early Würmian (Brörup to early Odderade; ca. 99–80 ka) are 13–14 °C. Values decline to <10 °C during the late Odderade and Stadial C (ca. 80–77 ka) around the MIS 5a/4 transition. This decrease is coeval with a pronounced decrease in Northern Hemisphere summer insolation. Values stay in the range of 9–11 °C during the Dürnten and Stadial D (ca. 54–74.5 ka) and increase again to 12.5 °C during the Bellamont 1 interstadial (ca. 54–46 ka). Reconstructed July temperatures track changes in arboreal pollen percentages at Füramoos and agree with a summer-temperature decrease during the early to mid-Würmian as reported by other palaeotemperature records from Europe and the North Atlantic. Our chironomid record from Füramoos provides valuable new insights into Würmian climate dynamics in Central Europe, and corroborates other temperature reconstructions from the early to mid-Würmian glacial period. • A new continuous chironomid-based temperature reconstruction from MIS5c to MIS3. • The main summer temperature cooling occurs ca. 85–75 thousand years ago. • Coldest July temperatures of 8.5 °C are inferred in Stadial C (correlated to GS 21). [ABSTRACT FROM AUTHOR]

The current climate warming phenomenon manifests itself with the occurrence of, among other characteristics, extremely hot months and seasons. Examples include the heat waves of April and May 2018 and of June 2019, which swept through large areas of Europe with considerable damage to nature and the economy. The study looks at thermal anomalies of this kind using average monthly air temperature records from 210 weather stations collected over the period 1951–2018. For the purpose of the study an anomaly was defined as a deviation of the average monthly temperature from the long-term average by at least two standard deviations. An anomaly was considered large-area if it occurred simultaneously at 20 or more stations, which corresponded to about one-tenth of the continent. The study found that positive large-area anomalies were increasingly frequent, some being recorded at 80 stations, and that no cool large-area anomalies were recorded after 2010. Large-area thermal anomalies of both types were the most frequent overall in Central Europe. Unlabelled Image • Large-area thermal anomalies (LATA, both negative and types) were the most frequent overall in Central Europe. • The bulk of LATA− occurred up to 1995, while the bulk of LATA+ were recorded after 1995. • The frequency of LATA+ is increasing faster than the frequency of LATA− is decreasing. [ABSTRACT FROM AUTHOR]

The aim of this study is to analyse the influence of atmospheric circulation over Central Europe on the long-term variability of relative sunshine duration (RSD) and air temperature in Poland. The analysis of data from 23 stations located in different parts of the country has made it possible to indicate to what extent the trends of these two climate elements are related to atmospheric circulation and whether they occur throughout the year or only in certain months. To this end, the author's own classification of circulation types was used, which relies on a set of indices related to the velocity and direction of geostrophic flow, as well as total shear vorticity, calculated using a gridded data set of sea-level pressures. The results of the research showed that atmospheric circulation over Central Europe has a significant impact on RSD and air temperature in Poland, but not on their upward trends in recent decades. The increase in the average annual values of both these climate elements was marked in almost every circulation type. This contradicts the assumption of classical synoptic climatology, which assumes that circulation types themselves are usually considered to be constant, i.e. that changes in air temperature can be related only to an increase or decrease in the incidence of the circulation types. • Atmospheric circulation has a significant impact on sunshine duration and air temperature in Poland • There was no relationship between the atmospheric circulation over Central Europe and the upward trends of these two elements • The increase in sunshine duration and air temperature was marked in almost every circulation type [ABSTRACT FROM AUTHOR]

We present a new chironomid record from sediments of former Lake Švarcenberk in South Bohemia (412 m asl, Czech Republic), located in the oceanic-to-continental macroclimatic transitional zone of eastern Central Europe. We provide estimates of Weichselian Late Glacial and Early Holocene (ca. 15–8 ka BP) mean July air temperatures on the basis of changes in the fossil assemblage using a joint Norwegian-Swiss transfer function. In our study, the climate was found to be relatively cold during the Late Pleniglacial, with July temperatures ranging between 11.2 and 12.3 °C. With the exception of the youngest section of this interval, temperatures during the Bølling-Allerød interstadial were relatively stable and warm, with values around 13.3–14.5 °C. During the Younger Dryas (YD), July temperatures varied between 12.7 and 16 °C, and these particular results are in agreement with other climatic reconstructions from the central to the eastern part of the European continent showing no or moderate summer temperature decrease during the YD, or even a slightly warming trend. A relatively warm and climatically stable early YD phase was followed by a variable and overall cooler younger phase. At the beginning of the Early Holocene, our reconstructed July temperatures increased to 17.7 °C. We demonstrate that general patterns of temperature changes inferred from chironomids during the Last Glacial Termination are similar to various multi-proxy reconstructions in Europe but we observe two unusually strong and abrupt cooling events: one that may be linked with the Gerzensee oscillation at the end of the Bølling-Allerød Interstadial and another that probably corresponds to the Preboreal Oscillation, although the temperature decreases in these intervals were much more pronounced than observed in other chironomid records from Europe, suggesting that local climatic factors and ecosystem responses may have overamplified these cold events in the temperature reconstruction. However, other proxies (geochemistry, pollen) support the interpretation of climatically driven palaeoenvironmental changes such as the development of vegetation cover, changes in lake productivity, pedogenesis and erosion. • The first chironomid record from eastern Bohemian Massif covering the Last Glacial Termination. • The changes in chironomids primarily represented response to past temperature change. • Two unusually strong and abrupt cooling events were observed. • In-lake processes may have been reinforced by other environmental changes. [ABSTRACT FROM AUTHOR]

The climate shift of the Last Glacial Maximum (LGM) strongly impacted the vegetation cover and related trophic chains of western Europe. Harsh, cold and dry conditions then prevailed in most regions, strongly impacting migrations and survival of human beings. Nonetheless, environments suitable for mammalian fauna to survive persisted in SW Europe thus providing refugia for hunters. Tooth enamel from large herbivorous mammal remains from archaeological sites located in southwest France and Spain were analyzed for their stable carbon and oxygen isotope compositions for documenting paleotemperatures and paleoprecipitations. These sites were occupied by humans between 25 ky and 16 ky. Skeletal remains of Cervidae, Equidae and Caprinae suggest colder and drier conditions relative to present-day. Paleoprecipitations were reconstructed from a modern-based transfer function using δ13C-values of apatite carbonate, then corrected for the low atmospheric pCO 2 value of the LGM. They ranged from ≈250 mm yr−1 on the Mediterranean façade, to ≈550 mm yr−1 on the Atlantic side. Setting the δ18O-value of the northeastern North Atlantic LGM-surface water to +0.8‰, based on Biscay Golf marine core studies, mean air temperatures inferred from 18O-data in apatite calcite were close to 14–15 °C (Mediterranean) and 6 °C–10 °C (Atlantic), i.e., about 4–5 °C and 5–8 °C higher than pre-industrial temperatures, respectively. The two areas thus define distinct clusters of air temperatures and precipitation regimes with strong negative offsets vs the Present. These isotopically-reconstructed climate conditions indicate a strong control from proximal surface ocean/marine waters, in particular of mean annual air temperatures. • LGM in SW Europe illustrates faunal and vegetation partitioning in provinces. • δ13C and δ18O of apatite carbonate were obtained on remains of large mammals. • MAP ranged from ≈250 mm yr−1 (Mediterranean side) to ≈550 mm yr−1 (Atlantic side). • MAAT were close to 14–15 °C (Mediterranean side) and from 6 °C to 10 °C (Atlantic side). [ABSTRACT FROM AUTHOR]

There is considerable demand for satellite observations that can support spatiotemporally continuous mapping of land surface temperature (LST) because of its strong relationships with many surface processes. However, the frequent occurrence of cloud cover induces a large blank area in current thermal infrared-based LST products. To effectively fill this blank area, a new method for reconstructing the cloud-covered LSTs of Terra Moderate Resolution Imaging Spectroradiometer (MODIS) daytime observations is described using random forest (RF) regression approach. The high temporal resolution of the Meteosat Second Generation (MSG) LST product assisted in identifying the temporal variations in cloud cover. The cumulative downward shortwave radiation flux (DSSF) was estimated as the solar radiation factor for each MODIS pixel based on the MSG DSSF product to represent the impact from cloud cover on incident solar radiation. The RF approach was used to fit an LST linking model based on the datasets collected from clear-sky pixels that depicted the complicated relationship between LST and the predictor variables, including the surface vegetation index (the normalized difference vegetation index and the enhanced vegetation index), normalized difference water index, solar radiation factor, surface albedo, surface elevation, surface slope, and latitude. The fitted model was then used to reconstruct the LSTs of cloud-covered pixels. The proposed method was applied to the Terra/MODIS daytime LST product for four days in 2015, spanning different seasons in southwestern Europe. A visual inspection indicated that the reconstructed LSTs thoroughly captured the distribution of surface temperature associated with surface vegetation cover, solar radiation, and topography. The reconstructed LSTs showed similar spatial pattern according to the comparison with clear-sky LSTs from temporally adjacent days. In addition, evaluations against Global Land Data Assimilation System (GLDAS) NOAH 0.25° 3-h LST data and reference LST data derived based on in-situ air temperature measurements showed that the reconstructed LSTs presented a stable and reliable performance. The coefficients of determination derived with the GLDAS LST data were all above 0.59 on the four examined days. These results indicate that the proposed method has a strong potential for reconstructing LSTs under cloud-covered conditions and can also accurately depict the spatial patterns of LST. • A new LST reconstruction method for cloud-covered pixels is proposed. • The reconstructed LSTs well captured the distribution of surface temperature. • The evaluations with GLDAS and air temperature data suggest its good performance. • The proposed method shows good potential for reconstructing cloud-covered LSTs. [ABSTRACT FROM AUTHOR]

Upcoming climate change effects will vary with region, season and time of the day. Existing annual and daily temperature cycles will shift and be reshaped, leading to increased air temperatures earlier and later in the year. Buildings will be affected by these changes, especially the ones using passive design strategies, whose performance is highly weather dependent. This study analyses the shift and reshape of annual and daily temperature cycles, focusing on when, where, and how passive design strategies (natural ventilation (NV), night cooling, and solar shading) are affected, going beyond season or yearly effectiveness. High temporal resolution (sub-daily and monthly) modelled data for the time frames (1971–2000) and (2017–2100) have been used to analyze upcoming changes in temperature, their interaction with solar radiation, and the consequent impacts on passive building strategies efficiency in European Union 43 most populated cities. The results show that changes in the diurnal temperature cycle will affect the daily temperature range (DTR), leading to two daily temperature cycle shapes: daytime (DTR increase) and a nighttime (DTR decrease), with different impacts on the heating and cooling seasons. Further, mild and warm days will occur earlier and persist until later in the year, shifting NV and shading seasons. In Northern Europe, NV season will be 6 weeks longer, while in Southern Europe it will be 9 weeks shorter. In Southern Europe, shading season will increase 2.5 months, direct solar radiation in south façades will increase 35% consequence of −13.5° in average maximum solar altitude, making overhangs less effective. • Climate change will affect the shape of the diurnal temperature cycles. • Days with reduced temperature amplitude occur in the heating season and increase residential heating demand. • Days with increased temperature amplitude occur mostly during the cooling season and increase cooling demand. • Shifts in annual temperature distribution will increase natural ventilation in the North of Europe and decrease in the South. [ABSTRACT FROM AUTHOR]

• The combined SVM/TBATS model improves pure TBATS or SVM air temperature prediction. • Dynamics of the weather conditions influences SVM/TBATS long-term prediction. • The lengths of the learning/testing data sets should be individually estimated. • The SVM/TBATS model can be successfully used for filling gaps in time series data. • SVM/TBATS predicted and measured temperature values lead to similar modelled yield. This paper explores the idea of combining Trigonometric Exponential Smoothing State Space model with Box-Cox transformation, ARMA errors, Trend and Seasonal Components (TBATS) with Support Vector Machine (SVM) model to estimate time series of the minimum and maximum daily air temperatures in a period of six years for various climatic localizations in Europe. It was found that a combined SVM/TBATS model can predict not only seasonality but also local temperature variation between subsequent days observed in daily data. Because the SVM sub-model uses not only results of TBATS prediction as an input data, but also several meteorological values, such modelling cannot be treated as a future time series estimation. Therefore, it has a potential to be used for filling gaps in the air temperature data. As is shown in our results, the precision of air temperature prediction improves when using the combined SVM/TBATS modelling, compared with pure TBATS or SVM modelling. For various locations, which can be related with different climatic conditions, this improvement ranged from 3% up to 14% for the maximum daily air temperature and from 5% to 25% for the minimum daily air temperature. The temperature sums calculated on the base of air temperatures predicted with SVM/TBATS models and from measured values did not differ more than 300°C (less than 1°C per day) in majority of cases. The average error in wheat yield prediction by WOFOST and DNDC models did not exceed 12.8% and 13.3%, respectively. [ABSTRACT FROM AUTHOR]

• We developed a stage-structured population dynamics model for Aedes albopictus. • The model includes temperature-dependent biodemographic functions. • We predict Ae. albopictus potential distribution, abundance and activity in the EU. The Asian tiger mosquito (Aedes albopictus) is one of the most invasive disease vectors worldwide. The species is a competent vector of dengue, chikungunya, Zika viruses and other severe parasites and pathogens threatening human health. The capacity of this mosquito to colonize and establish in new areas (including temperate regions) is enhanced by its ability of producing diapausing eggs that survive relatively cold winters. The main drivers of population dynamics for this mosquito are water and air temperature and photoperiod. In this paper, we present a mechanistic model that predicts the potential distribution, abundance and activity of Asian tiger mosquito in Europe. The model includes a comprehensive description of: i) the individual life-history strategies, including diapause, ii) the influence of weather-driven individual physiological responses on population dynamics and iii) the density-dependent regulation of larval mortality rate. The model is calibrated using field data from several locations along an altitudinal gradient in the Italian Alps, which enabled accurate prediction of cold temperature effects on population abundance, including identification of conditions that prevent overwintering of the species. Model predictions are consistent with the most updated information on species' presence and absence. Predicted population abundance shows a clear south-north decreasing gradient. A similar yet less evident pattern in the activity of the species is also predicted. The model represents a valuable tool for the development of strategies aimed at the management of Ae. albopictus and for the implementation of effective control measures against vector-borne diseases in Europe. [ABSTRACT FROM AUTHOR]

• Outbreaks of Dendrolimus pini cause damage to forests in Central Europe. • Range expansion of D. pini in Europe has been observed, due to climate changes. • Climate warming leads to shorter periods between D. pini outbreaks. • Forest protection should include increasing resistance of stands to D. pini. • Monitoring pest abundance and protective measures are presented. Present forestry faces many challenges and threats, among which possible climate change is one of the most important. The increase in air temperatures combined with droughts and, consequently, the prolongation of the growing season may be conducive to the increased activity of some insect species, for example the pine tree lappet moth Dendrolimus pini. This species appears in cyclical outbreaks, causing serious damage to Pinus spp. forests in Central Europe. It is assumed that the observed climate warming is the reason for the species' observed expansion in the last two decades and the increase in its threat to forests in northern and southern Europe. A reduction of the period between the outbreaks to 2–3 years from 4 to 16 years has been observed since the 2000 s, which can lead to an increase in this threat. For the above reasons, it is important to undertake management activities aimed at increasing the stand's resistance to the outbreaks of D. pini. The protective measures should first include the identification of environmental conditions and features of stands to locate the areas particularly endangered by the pest. It is also important to monitor pest numbers and determine the criteria for assessing the condition of the population and the phase of outbreak. The publication presents an overview of the status of D. pini in Europe and its integrated management with particular focus on prevention activities aiming at increasing the resilience of forests to pest outbreaks, D. pini monitoring system and control methods for reducing the number of this species population. [ABSTRACT FROM AUTHOR]

We have examined the joint impact of daily maximum temperature and air stagnation on observed maximum daily 8-h running average (MDA8) and hourly near-surface ozone (O 3) over eight regions of Europe for the summer period 1998–2015. The percentage of stagnant area in a region is a better predictor of summer MDA8 O 3 in central/southern Europe (correlation coefficient R = 0.50–0.70) than in the north (R = 0.06–0.39). The correlations of MDA8 O 3 with temperature are higher than with stagnation for most regions, and the impact of stagnation on those correlations is region-dependent. MDA8 O 3 mixing ratios consistently increase over central/southern Europe under stagnant conditions, but this has not been found for some temperature ranges in the north. Under non-stagnant situations and relatively high temperatures (20–25 °C), southerly advection often brings aged air masses from more polluted areas to the receptor regions in the north. Furthermore, the occurrence of stagnation tends to amplify the ozone diurnal cycles in the center/south of the continent, yielding lower nighttime and higher daytime mixing ratios than on non-stagnant days, again with a less clear effect in the north. Changes in planetary boundary layer height, accumulation of ozone and precursors, and subsequent photochemical production during stagnant days are the presumed underlying mechanisms for the amplification of the diurnal cycles. The results from this study prove that the effects of stagnation on summer ozone are regionally dependent across Europe. Consequently, climate model projections of increases in stagnation should not directly be translated into degraded air quality without a proper assessment of the regional impacts. [ABSTRACT FROM AUTHOR]