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Return periods (Ts) are used to estimate the interval of time between natural hazard occurrences of a certain size and assess the risks associated with hydrological occurrences, climate extremes, structural failures and seismicity. Despite Ts being widely used, they are characterized by strong misconceptions and ambiguities. Moreover, although they have been successfully used when discussing storm surges, high tides and extreme precipitation, concerns arise from their use in assessing probabilities of future global mean sea level rise (SLR). Most papers discuss SLR return periods considering storm surges or high tides and not SLR itself, as a separate and unique hazard. Sea level rise due to storm surges or tides is regional and temporary and differs from the global SLR, which is a long lasting and slow phenomenon. This paper discusses these misconceptions and misuses of return periods in assessing flood risk and the probability of sea level rise at the global level and suggests a method for assessing likelihoods of climate change risks that can be widely accepted and commonly used by all stakeholders and decision makers for all types of climate hazards. [ABSTRACT FROM AUTHOR]

The potential for the generation of pico- and micro-hydropower through hydraulic energy recovery has been demonstrated across many sectors of the water-energy-food nexus, often termed hidden hydropower. The potential to recover energy from hidden hydropower in water supply, crop production, food processing, and energy production has been demonstrated via numerous in-depth case studies, regional assessments, and physical experiments. This paper presents a holistic overview of the potential role and impacts of micro-hydropower energy recovery on the water-energy-food nexus in the context of climate change. The paper comprises a review and synthesis of the available literature. The paper outlines the potential impacts of hidden hydropower on cost of water supply, energy and food production, considering also the potential impacts on crop yield and food supply. Policy and technological barriers to the exploitation of hidden hydropower resources within the nexus are outlined and recommendations to overcome these are provided. The results of this investigation highlight the potential of micro-hydropower energy recovery in water systems to reduce energy consumption by 0.005–3.7% across various sectors and regions, with consequent impacts in the operating and consumer costs of food, water and energy, as well as on the CO2 emissions of these activities. This hidden hydropower has the potential to ease the pressures of the water-energy-food nexus and is an important element of the route towards sustainability within the nexus. [ABSTRACT FROM AUTHOR]

This paper investigates the potential impacts of climate change and anthropogenic activities on the transboundary river of Aoos/Vjosa, flowing through Greece and Albania, and proposes strategies for its protection. The paper analyzes the current state of the river and its ecosystems, identifies the key drivers of change, and examines the potential impacts of future climate scenarios and human activities. Using climate data and GIS mapping, the study highlights the importance of sustainable development and cross-border cooperation to ensure the long-term health and sustainability of the river and its resources. [ABSTRACT FROM AUTHOR]

Climate-change-induced environmental impacts has an especially strong influence on water resources. Declining water availability not only results in droughts, but is also responsible for decreasing the quality of water in water-scarce regions, such as the South Caucasus. Armed conflict between Armenia and Azerbaijan in 2020 occurred during the recent major war in the South Caucasus. In this paper, I ask how will intensifying climate change in the region affect the current political situation? Is there any chance of multilateral cooperation for water management? [ABSTRACT FROM AUTHOR]

The coastal areas of Chile are undergoing major transformations associated with changes in the frequency and intensity of coastal storms, alterations in the rainfall regime with a megadrought of more than 10 years, and variations in ocean currents, which have generated a series of impacts related to beach erosion, the alteration of coastal wetlands and the effects on coastal cities. Faced with this problem, it is necessary to incorporate multiple monitoring methodologies that are complementary to existing ones, and that promote the incorporation of communities as fundamental axes in data collection. In this paper, we present the CoastSnap initiative implemented in Chile, whose results have been notorious, despite the short implementation time. Up to July 2023, the communities had shared 350 photographs that have allowed for analysis of the variability of the beaches, allowing for the quantification of variations on average up to 45 m wide in some of their beaches. [ABSTRACT FROM AUTHOR]

Land use and land cover (LULC) change is a major driver of environmental change in District Bahawalnagar, Punjab. LULC change can lead to changes in soil quality, water availability, and climate, all of which can affect crop yields. LULC change can also lead to the loss of agricultural land, forest land, water bodies, and an increment in urban land that causes climate change and affects the agricultural sector. The study area showed that in the last thirty years, the population increased, built-up land increased, and agricultural land dropped by 30%. The present status of knowledge is reviewed in this paper on the impact of LULC on agricultural production in District Bahawalnagar. The conversion of agricultural land to urban development in District Bahawalnagar has led to a decline in crop yields of an average of 10%. The production of wheat and rice, the two major crops grown in District Bahawalnagar, is influenced by LULC changes. This study also found that the loss of agricultural land has resulted in an increase in soil salinity, which has further reduced crop yields. The detrimental effects of LULC change on agricultural output in District Bahawalnagar can be mitigated by adopting sustainable land management practices. These practices include reforestation, conservation agriculture, and water conservation. The government of Pakistan can also play a role in mitigating the negative impacts of LULC change on agricultural production by developing and implementing land use plans that protect agricultural land from conversion to other uses. More research is required to fully comprehend the effects of LULC and develop effective management strategies. However, LULC is a major challenge that must be addressed if we are to ensure food security in the future. [ABSTRACT FROM AUTHOR]

The Amery Ice Shelf is a major source of sea ice, whose production is linked to the global climate. In 2019, a collapse event occurred in the Amery Ice Shelf; sea ice production before and during this collapse needs to be studied. In this study, polynyas in the Amery Ice Shelf were identified according to ice thickness, and sea ice production was obtained by calculating the heat flux during winter (March–October) in 2013–2020. It was found that the sea ice production in the polynyas fluctuated greatly, and the maximum annual ice production occurred in 2018, which reached 225.4 km3. As for the collapse event in 2019, it is assumed that it may have exacerbated the volatility and instability of sea ice production. [ABSTRACT FROM AUTHOR]

In this paper, EXTRASTAR software (EXTRemes Abacus for STAtistical Regionalization) is illustrated, which provides a general framework for extreme value analysis, specifically for Annual Maxima (AM) time series. The proposed methodology represents a useful and quick approach to carry out onsite and regional statistical investigations of extreme events, which is also suitable for climate change scenarios. EXTRASTAR was tested with the AM time series at daily resolutions for the entire Italian rain gauge network by implementing EV1 (Extreme Value Type I), GEV (Generalized Extreme Value) and TCEV (Two-Components Extreme Value) probability distributions. [ABSTRACT FROM AUTHOR]

With climate change, dry periods are more frequent, and intense short rainfall events are increasing in Mediterranean areas. It is essential to have better and more accurate territorial planning that does not expose the population to risks. The feasibility of small dams' construction was studied in the municipality of Guarda to improve and include the information in the respective Master Plan. This paper presents the methodologies implemented and results obtained in the identification of sites for the possible construction of hydraulic structures of less than 15 m height to retain and store water. [ABSTRACT FROM AUTHOR]

To provide quantitative elements to the expected rate of change of flood quantiles in Alpine basins due to global warming, a systematical assessment of a river network is undertaken in this paper through the implementation of a geomorphoclimatic approach. The model, called "FloodAlp" produces the flood frequency curve of mountainous catchments based on the stochastic interaction of precipitation and temperature. In view of a widespread application, FloodAlp was revamped here and applied to all the sections of the river network of the Chisone basin (Northwest Italy) identified through a 50 m resolution digital elevation model (DEM). We show that, based on the decrease in snow-affected contributing areas, flood frequency can increase up to 8 times compared to the current frequency, with amplifications depending on the local elevation characteristics of sub-basins. [ABSTRACT FROM AUTHOR]

In this paper, two different strategies are presented that allow for the assessment of the effects of climate change on urban pluvial flooding, in order to understand potentialities and limitations, advantages and drawbacks. The two strategies are hereby defined as "top-down" and "bottom-up", according to the relative position of climate change modelling with respect to flood modelling (upstream for top-down, downstream for bottom-up). To provide a practical example, the two strategies are applied to a case study located in Naples, Italy. However, they can be successfully extended for the assessment of any potential impact of climate change in any location. [ABSTRACT FROM AUTHOR]

According to the recent IPCC report, the Mediterranean, and consequently the region of Sitia, is one of the European "climate hotspots". Its complex geomorphology and multiple locations with very distinct microclimate characteristics make high-resolution climate projections critical for the appropriate determination of effective local adaptation policies. The paper demonstrates the significance of the dynamical downscaling of climate information from 20 km x 20 km to a 5 km x 5 km scale of temperature, precipitation, drought, and fire risk for the region of Sitia and present, near-, and far-future climate projections using RCP4.5 and RCP8.5 scenarios. [ABSTRACT FROM AUTHOR]

The changes in the local microclimate from the installations of renewable energy systems and thermal units for the production of electrical power, as well as the statistical analysis of the data recorded from various official data sources are presented in this paper. In this context, bibliographic data were recorded, such as temperature and rainfall data in the vicinity of units for the production of electrical power from renewable energy systems and power plants. The data were collected from various databases and an assessment of the impact of different types of power plants on the local climate was conducted. The different types of energy sources are thoroughly categorized. Furthermore, climate data of the wider location of selected energy production plants were analyzed before, during and / or after the end of their operation. Finally, an analysis will be carried out and conclusions will be drawn regarding the climate change endured in the said locations. [ABSTRACT FROM AUTHOR]

Poor air quality remains the largest environmental health risk in Europe, despite the EU policy efforts. Especially in cities, the synergistic interactions between the urban heat island and urban pollution result in premature mortality, associated with cardiovascular and respiratory diseases. Mediterranean urban areas are particularly susceptible under the consideration that the intensity, frequency, and duration of heat waves will increase due to climate change. The LIFE SIRIUS project designates that air quality management needs to go beyond traditional approaches in order to consider synergistic effects. This paper assesses the impact of temperature on daily mortality from 2004 to 2019 in the Republic of Cyprus with the use of a Generalized Additive Model (GAM). The association between mean daily temperature and mortality is nonlinear, implying that a prompt rise in deaths occurs when temperatures are high, while for colder temperatures, the effect is delayed. We report an inverted J-shaped relationship between mean temperature and mortality, with the most prominent effects on human health documented at low temperatures. The population under study appears to be acclimatized to local conditions, as mortality increases after 10 days of exposure to the environmental risk. The results of this study will assist in the definition of city-specific thresholds above which health warnings for the protection of the local population will be issued, in the framework of LIFE SIRIUS. [ABSTRACT FROM AUTHOR]

Europe has been experiencing an increasing number of sweltering heat waves in recent years. This run of hot extremes induces a significant impact on the human environment, especially in terms of excess mortality, highlighting the urgent need for improved heat-health action planning. This is particularly true in countries situated in the eastern Mediterranean, which is considered a climate change hot spot. To increase preparedness and response to overheating risks, heat-health warning systems (HHWSs) are of vital importance. In this direction, the principal aim of the HEAT-ALARM research project is to provide a novel scientific and technological framework for the development of efficient HHWSs, employing Greece as a testbed. Going beyond the simple notion that outdoor meteorological conditions alone can adequately describe the heat-health nexus, a sophisticated human-biometeorological index, the modified physiologically equivalent temperature (mPET), is used. Advanced statistical models and tools are employed in order to establish a clear link between mPET and excess mortality at regional-unit administrative level. Moreover, urban climate factors produced by combining remote sensing and geographical information system techniques are incorporated into the HHWS via a state-of-the-art numerical weather prediction model. The latter includes a scheme that combines the parameterization and modeling of building effects and energy, respectively, in order to account for the urban indoor thermal conditions and the intra-urban differential heat exposure within the five highest populated cities of Greece (Athens, Thessaloniki, Patras, Heraklion and Larissa). Further, the human body's acclimatization ability is considered, as well as the physiological characteristics of different vulnerable groups of people, including the elderly, women and outdoor workers. The current paper describes the scientific background of HEAT-ALARM and provides preliminary results associated with the project's realization. [ABSTRACT FROM AUTHOR]

Climate change is unquestionable and climate disasters are projected to increase in frequency and intensity. The adverse effects of climate change on people's health are significant and depend on the type of climate hazard that threatens vulnerable populations in different regions around the world. The climate change impacts on public health include not only the direct effects on people's physical and mental health, but also the side effects of climate change on critical infrastructure and systems that are involved in assisting healthcare operations. This paper develops a methodology for assessing the impacts of climate extremes based on people's and systems' vulnerabilities and builds a global framework for assessing the public health risk of climate change. [ABSTRACT FROM AUTHOR]

The effects of climate change are now evident on a global level and indisputable even to the most skeptical. Melting ice, rising sea levels, and changing climate zones are a daily occurrence and subject of debate in the media. Beyond the obvious effects of these phenomena on human lives, countless others arise and await being studied. Meanwhile, it has been proven that many health problems are related to changes in weather and large fluctuations of temperature. Specifically, studies have been conducted to correlate the rupture of intracranial aneurysms with seasonal and climatic conditions. The conclusions of these studies linked the rupture of intracranial aneurysms with higher temperatures, as well as with higher atmospheric pressure. Inevitably, one of the questions raised is whether the change in weather brings about conditions that favor the rupture of intracranial aneurysms throughout the year. The purpose of this paper is to present the results of studies that correlate these two factors and, then, to demonstrate that these meteorological conditions now prevail throughout the year, influencing, perhaps, and distributing the rupture of intracranial aneurysms during all seasons. [ABSTRACT FROM AUTHOR]

One of the impacts of climate change is an increase in the frequency and intensity of extreme rainfall events. This has very significant social and economic consequences for the affected areas (flooding, loss of life, destruction of infrastructure, etc.). Future trends indicate a further increase in extreme rainfall in the second half of the century, making the need for the timely and accurate forecasting of these phenomena more urgent than ever. However, despite the technological development of weather and climate models in recent years, there are still limitations in detecting the extremes, especially regarding the precipitation parameter. Extreme precipitation events show a link with temperature. The Clausius-Clapeyron (CC) equation, which relates temperature to saturation vapor pressure (es), is used to study the sensitivity of precipitation to temperature increase because it can estimate the increase in the available atmospheric water vapor with respect to temperature. Focusing on the Thessaloniki region in Greece, the aim of this paper is to investigate the applicability of the Clausius-Clapeyron relation to the scaling relationship between extreme precipitation intensity and surface air temperature. An additional attempt is also made to test the possibility of improving the underestimation that the reanalysis models exhibit in recording the extremes and in particular the ERA5 Land dataset. [ABSTRACT FROM AUTHOR]

Global Change Explorer (GCE) is an interactive web-based tool for investigating the complexities of global change. GCE uses the ANEMI simulation model developed at the University of Western Ontario, Canada. ANEMI simulates system dynamics to offer information on Earth's dynamic processes and the behaviours that instigate change. The ANEMI model is an integrated assessment model of global change that emphasizes the role of water resources. The model sectors that comprise ANEMI3 (the current version of the model) are that of the climate system; carbon, nutrient, and hydrologic cycles; population dynamics; land use; food production; sea level rise; energy production; the global economy; persistent pollution; water demand; and water supply development. GCE is designed to allow the use of ANEMI to simulate various future scenarios related to five main themes: climate change; population dynamics; food production; water quality; and water quantity. The users are presented with the opportunity to ask different questions, select simulation runs, and evaluate model outputs. [ABSTRACT FROM AUTHOR]

The proposed climate monitoring system aims to address the substantial risks to human health, climate stability, and ecological balance posed by air pollution, utilizing Raspberry Pi as a central procession unit and integrating various sensors which also incorporate sensors to measure the concentrations of PM1, PM2.5, PM10, and black carbon. This method meets the need for effective and immediate air quality monitoring and offers useful information to communities, academics, and policy makers. Through IoT connectivity, the gathered data are sent to a cloud-based platform for analysis and visualization. The system offers a user-friendly interface that presents actionable insights for informed decision making. Its warning capabilities alert users when pollution levels exceed thresholds, and this system also contributes to a comprehensive understanding of air pollution. By measuring particulate matter and black carbon levels, it supports the development of effective air quality management strategies. The system helps to take proactive measures and create cleaner and healthier environments. In conclusion, the proposed climate monitoring system utilizing Raspberry Pi, sensors, IoT connectivity, and machine learning techniques offers an effective and real-time solution for monitoring air quality. The integration of IoT connectivity allows for remote access to air quality data, while machine learning algorithms analyze the data and initiate alerts. [ABSTRACT FROM AUTHOR]

The Fez region in Morocco has experienced changes in agricultural land use as a result of climate change. These changes include erratic rainfall, rising temperatures, and evapotranspiration. The objective of this research is to investigate the impact of these changes on agricultural land use between 2018 and 2022 using remote sensing data (sentinel-2 and MODIS), climate data, drought index (Vegetation Condition Index (VCI)) and two machine learning algorithms (Random Forest (RF) and Gradient Tree Boost (GTB). The RF and GTB algorithms were trained and tested, and their performance was analyzed, revealing that the GTB algorithm is more efficient than the RF, with a Kaffa coefficient of 91% and overall accuracy of 93%. The analysis of climate change on land use and land cover (LULC) variations revealed a significant (54%) reduction in rainfall. Furthermore, agricultural land use and water were reduced by 41% and 17%, respectively. Conversely, barren land and built-up areas increased by 58% and 4%, respectively, and the annual mean VCI decreased from 39.72 in 2018 to 19.9 in 2022. The study concluded that climate change had a significant impact on the region's agricultural land cover, and decreases in rainfall directly affect agricultural land use. [ABSTRACT FROM AUTHOR]

Water plays a vital role in sustaining life and meeting the water needs of various sectors, such as agriculture, industries, and households. As water resources continue to be depleted, several hazards arise for communities. Declining water quality, a declining water table, reduced plant growth, droughts, diminished agricultural productivity, and the underutilization of power generation stations are some of the hazards associated with these conditions. Therefore, it is crucial to monitor the changes in water resources. The traditional methods used for measuring water storage face various challenges, including limited spatial coverage, low temporal resolution, high cost and resource requirements, and accuracy limitations. To address these challenges, remote sensing sensors such as the GRACE satellite provide rich sources of information that can be used to evaluate water reserves. Moreover, the Google Earth Engine provides access to a wide range of satellite imagery and geospatial data for various applications, making geospatial information more accessible and enabling informed decisions. This study analyzed the GRACE satellite time series data from 2002 to 2017 to investigate and compare water storage changes in Iran and six neighboring countries: Turkey, Iraq, Saudi Arabia, Turkmenistan, Pakistan, and Afghanistan. The final statistical analyses indicate a decrease in water reserves in almost all mentioned countries. The analysis of the results shows that Iran ranks second in terms of water reserve consumption after Iraq, which had the worst performance. Our study concludes with a concerning outlook on water storage in Iran, primarily attributed to inefficient water resource management, reduced rainfall, drought, and excessive withdrawals. [ABSTRACT FROM AUTHOR]

Climate change has directly impacted Earth's habitats, resulting in various adverse effects, such as the desiccation of water bodies. The process of identifying such changes through field observations is time-consuming and costly. By using remote sensing techniques, it has become easier than ever to monitor changes in the environment. Radar satellites, unlike optics, can acquire data in all weather conditions, regardless of the time of day. These data can provide valuable information about the environment and surface roughness. Various methods have been proposed for detecting changes, which can be divided into classic and deep learning methods. Classic methods only use image information, such as radar backscatter, which cannot extract spatial information. Sentinel-1 (S1) is an Earth observation radar sensor that provides free access to SAR (Synthetic Aperture Radar) images. This study aims to compare the performance of two classic methods, a ratio index (RI) and Markov random field (MRF), with deep learning networks in detecting changes. As a deep network, Inception CNN (convolutional neural network) is presented as an enhancement of the original CNN to detect the changes. To evaluate methods, two instances of S1 images from Lake Poopó, located in the Altiplano Mountains in Oruro Department, Bolivia, are used as a primary dataset. The results of the comparison models were assessed using three evaluation metrics: Overall Accuracy (O.A), Missed Error (M.E), and Kappa Coefficient (K). Based on the evaluations, the Inception CNN performed exceptionally in all metrics, with O.A, K, and M.E rates of 97.35%, 90.28%, and 9%, respectively. Meanwhile, the ratio index had poor performance, with 83.27%, 29.05%, and 75.03%, respectively, for O.A, K, and M.E. These results indicated that the Inception CNN could provide better performance in detecting changes from S1 images. [ABSTRACT FROM AUTHOR]

Agricultural management guarantees food security and economic development in various countries by applying new technologies to improve management practices. This study aims to identify the geomatic tools and their relationship with the agricultural activities used in cartography by reviewing scientific publications that contribute to improving agricultural management practices. The methodology consists of (i) a data source search strategy related to geomatics and agricultural management; (ii) data analysis; and (iii) a literary review of the contribution of geomatics in agricultural management. The results show that a large part of the studies orients to agricultural cartography and a smaller number to the use and cover of land (LULC) by agricultural activity, cadastre and precision agriculture. The studies focus on improving agricultural management practices to contribute to food security and combat the impacts of climate change (Sustainable Development Goals (SDGs) 2, 12 and 13). [ABSTRACT FROM AUTHOR]

Guaranteeing the sustainability of irrigation under the increasing pressures related to resource scarcity and climate change is a major global challenge, specifically in water-scarce areas. The present work proposes a methodological approach and a technological solution to improve operation and management of a critical on-demand pressurized irrigation system. The potential of using an innovative off-grid valve, the green valve, for the real-time monitoring and adaptive control is proven through numerical simulations. Particular emphasis is given to the energy balance feasibility of the system during a typical irrigation season. Reference is made to a real network located in southern Italy. [ABSTRACT FROM AUTHOR]

Nature-Based Solutions (NBSs) are considered worldwide as a suitable approach for mitigating the impact of industrial agriculture on sediments and nutrient losses. However, their actual effectiveness is still questioned. In cases where site measurements of NBS performance are scarce, models can provide useful insights if accurately set. This study analyzed the effects of vegetated buffer strips (VBSs) and winter cover crops (WCCs) planted in some herbaceous cropping systems within the Massaciuccoli reclamation area (Vecchiano, Central Italy). Analyses stem from modelling water and soil dynamics by applying SWAT+ at field scale on high resolution close-range photogrammetric digital terrain model (DTM), real crop rotations, and a detailed calendar of the main agronomic interventions. The NBS implementation was modelled in two experimental areas, showing contrasting soil properties. Comparing results from the modelling of different scenarios highlighted that NBS mitigative effect is influenced by soil properties and local topographic irregularities, which could induce concentrated flows. Long term climate changes can induce relevant different effects by varying the nature of soil. [ABSTRACT FROM AUTHOR]

Episodes of NNW-erly windstorms, known in the area of Balkan Peninsula as Vardaris, were identified, with the aid of wind archive data, from the Regional Meteorological Centre of Makedonia of the Hellenic National Meteorological Service of Greece. The study of the seasonal, interannual, and diurnal variations of the occurrence of Vardaris windstorms, as well as their intensity, shows that it is a severe, long-lasting, and mainly winter-time feature, usually commencing in the morning hours. Preliminary results of the study of dynamic features accompanying Vardaris have shown that these windstorms are almost totally associated with cold fronts coming from northern sectors. The presence of a northerly jet or a tropopause fold aloft contributes to increases in the intensity or duration of the windstorms. The connection of Vardaris with these dynamical features implies that the observed negative (positive) trends of the occurrence frequency/duration (intensity) of Vardaris windstorms is in accord with the scenario of climate change. [ABSTRACT FROM AUTHOR]

Climate change due to extended fossil fuel utilization strongly affects islands all over the world. Greece has a large number of islands of various sizes. As far as the electrification status and the climate surcharge of Greek islands is concerned, the current work is concentrated on the non-interconnected group of islands that cover their electricity demand on the basis of local oil- based thermal power stations. In this context, the EU-originated effort to drastically change the local electricity generation fuel mix was examined. More specifically, under the recent Territorial Just Transition Plan for the islands, a variety of actions is proposed in view of the "GReco-islands" initiative. Applying the proposed clean-green solution on a representative island (e.g., Patmos island), one may estimate the expected carbon dioxide emissions reduction. Finally, the necessary investments cost may be estimated due to the clean-green decarbonization actions implemented. [ABSTRACT FROM AUTHOR]

Human-caused climate change is linked to changes in some types of climate extremes such as high- and low-temperature extremes. Extreme temperature poses risks to several sectors of society and, more importantly, on human health. In Europe, the population affected by high temperatures is expected to increase as opposed to the number of people exposed to cold weather. Nevertheless, cold-related mortality is an important public health problem across Europe, and in southern (warmer) areas, the impact of low temperatures is higher. In this study, we analyzed mortality data from three Greek regions and investigated potential effects of the January 2017 cold spell on mortality attributed to cardiovascular disease. [ABSTRACT FROM AUTHOR]

Climate change is linked to a higher risk of hydrometeorological disasters, which are driven by both the increased global surface temperature, which leads to more frequent droughts, and heavy rainfall events inducing floods. The Municipality of Ermionida is a dry area in Greece facing flash flood events, mainly during the autumn and early winter period. To address this, the Municipal Enterprise for Water and Wastewater of Ermionida (DEYA.ER) and the Laboratory of Climatology and Atmospheric (LACAE) of NKUA are collaborating on a project entitled "Design of a smart early warning hydrometeorological system (EASY)". The project aims to develop an integrated local-scale forecasting system for flood awareness and, ultimately, for protection purposes. In the context of EASY, an online tool for data processing is provided, including hydrometric and meteorological monitoring, and it is a user-friendly platform that allows real-time access to data and enables the capability of designing specific diagrams according to the parameter and station. [ABSTRACT FROM AUTHOR]

This study investigates the spatial distribution of optical and microphysical dust properties in Europe and possible differences between the Saharan and Saudi Arabian deserts' dust particles based on the AERONET network. Data were collected within the period from 2001 to 2018 from 16 different stations. Pure dust conditions were identified. The Saudi Arabian lidar ratio (at 440 nm) was determined to be 53 ± 7 sr, much lower than the Saharan lidar ratio at the same wavelength, which was found to be 66 ± 10 sr. Particle depolarization ratio values at 440 nm were similar for both regions. Although our findings are consistent with earlier studies based on AERONET products, they do not agree with lidar observations. We found significantly larger lidar ratios at 440 nm both for Arabian dust (difference of 15 sr) and Saharan dust (difference of 13 sr) compared to lidar observations. These differences are smaller at 532 nm. Differences at both 440 and 532 nm between AERONET and lidar observations were on the order of 5 sr for Arabian dust and even smaller (order of 2 sr) for Saharan dust. [ABSTRACT FROM AUTHOR]

Under the framework of the European project "FirEUrisk", the present work aimed to spatially assess the climate change signal of fire weather danger in the Attica region at a high resolution of 5 km. For this purpose, a methodology was applied to investigate the projected changes in fire weather conditions under two emission scenarios and two future periods. The fire weather assessment was based on the fire weather index system and other related indices. The calculated indices were derived from high-resolution validated simulations. Large increases in FWI90 were observed during all periods and under both emission scenarios, mainly in the eastern parts. It is estimated that the northeastern parts will encounter more than 70 days of extreme fire weather, which corresponds to a future change of an increase of more than 45 days compared to the historical period. A change of more than 50% in the ISI will be observed in almost the entire region in the near future under RCP4.5, while this change is restricted mostly to the eastern Attica region under RCP8.5 in both periods. [ABSTRACT FROM AUTHOR]

Climate change has increased forest fire risk across Europe, leading to negative impact on air and water quality, biodiversity, soil and landscape aesthetics. Fire events in Mediterranean areas are linked to adverse effects on watersheds' hydrological regimes and increased surface runoff. The objective of this work is to investigate the hydrological response under pre- and post-fire conditions at a catchment scale. The study area is the mountainous area affected by the recent fire events of July 2021 in Cyprus. The methodological approach that was developed and applied involves the GIS-based implementation of the time-area (TA) diagram method for the unit hydrograph (UH) determination, under the two scenarios (pre- and post-fire), as well as the estimation of hydrological losses using the SCS-CN method for both scenarios. Two typical rainfall-runoff events for return periods of 20 and 100 years are compared for both scenarios regarding total runoff volume, peak discharge and time to peak. This first investigation of hydrological changes before and after a fire event in the area leads to the conclusion that, mainly due to the reduction of vegetation and soil permeability, there is a significant increase in the peak flow discharge and the total runoff volume. [ABSTRACT FROM AUTHOR]

This pilot study aims to evaluate the impact of climate change on the critical stages of crop growth. Data from agricultural stations in Greece were analyzed to assess the effects of climate change on the country's agriculture, focusing on areas vulnerable to frost, as identified by the Hellenic Agricultural Insurance Organization. The study examined the differences in climate patterns between continental and coastal agricultural regions to determine which areas are more resilient to local climate change. The frequencies of frost events and government subsidies were analyzed. The significance of early spring temperatures and their potential consequences for plant growth and vegetation, if followed by late-frost incidents, was emphasized. The severity and impact of frost events vary depending on the location, vegetation type, and growth stage. The economic importance of frost-sensitive crops, like deciduous fruit trees, citrus, and vines, in Greek agriculture has been highlighted. Given the increasing frequency of adverse weather conditions, the study underscores the need for a resilient and sustainable approach to agriculture, focusing on prevention and adaptation to climate variations. [ABSTRACT FROM AUTHOR]

In the present study, the spatial and temporal variability of the Aridity Index (AI) in the Mediterranean region during the 30-year period 1971-2000 is analyzed. The analysis is performed on a decadal timescale. Subsequently, the projected change in the AI in the periods 2031-2060 (near future) and 2071-2100 (far future) under the RCP4.5 and RCP8.5 emission scenarios in comparison with 1971-2000 (reference period) is presented. The input of the calculations are simulation results supplied by the CORDEX EU project. In total, an ensemble of 20 combinations of global climate models (GCMs) and regional climate models (RCMs) are used. The calculation of the AI is based on potential evapotranspiration, which, in turn, is calculated according to the classic method of Thornthwaite. Our results show that drier conditions are to be expected in the future along a wide zone in southern Europe, including Spain, Italy, Bulgaria, Greece and Turkey, as well as in Northern Africa, particularly under the RCP8.5 scenario and towards the end of the century. [ABSTRACT FROM AUTHOR]

The complete blood count (CBC), a cost-effective blood test, offers insights into the cell composition of blood, including white and red blood cells and platelets. Novel inflammatory biomarkers derived from combinations of CBC parameters include the neutrophil-to-lymphocyte ratio, reflect systemic and local inflammation. In this retrospective study, we successfully leveraged bioinformatics analysis to examine potential correlations between CBC biomarkers and climate and environmental factors, including temperature, humidity, and rainfall, in Fokis, Greece for a 4-year period (2019-2022). Our findings provide valuable insights into how these environmental factors might influence blood cell parameters in the general population. [ABSTRACT FROM AUTHOR]

Forecasting and characterizing fire weather conditions over a region days in advance is of great importance for developing early warning systems and supporting effective wildfire management. Furthermore, it is important for increasing awareness and preparedness of all the involved entities, including both the public and practitioners. In addition, considering climate projections over the Mediterranean, which indicate an environment more conducive to wildfire activity, the need for timely forecasting of extreme fire weather days becomes increasingly urgent. In this work we present an application of the newly developed fire weather forecasting framework that employs the concept of critical fire weather patterns on the 2018 Mati wildfire. Within our fire weather forecasting framework, we assign the large-scale circulation pattern to one of the predefined critical fire weather patterns of Greece which are associated with different levels of fire danger based on the dominating fire weather conditions and expected fire behavior. For the purpose of this study, we use historical forecast data to assess the predictability of the synoptic-scale fire weather conditions using the critical fire weather patterns, and we discuss the main advantages of the presented forecasting framework. This fire weather forecasting framework is applied operationally by the METEO Unit of the National Observatory of Athens within the frame of the "FLAME" project since the 2022 fire season in Greece. [ABSTRACT FROM AUTHOR]

The Atlantic Meridional Overturning Circulation (AMOC) is a major oceanic circulation system in the Atlantic Ocean, which transports heat to the poles and cold saline waters to the tropics. The AMOC mechanism is responsible for many climate and weather systems; however, it is naturally unstable, and it changes in time depending on sea-ice melt, wind patterns, solar radiation variations, etc. At the same time, there are recent indications that the AMOC is in a weaker state than previously thought with impacts more severe than expected. Knowing that the AMOC can impact remote systems, and given the risk the Mediterranean faces with climate change progressing, we focus on the relationship between the AMOC and the Mediterranean climate, based on AMOC indicators and monthly ERA5 fields (sea surface temperature, air temperature and total precipitation) from 1959 to 2021. We find that the two systems exhibit a relationship although it is not homogenous. More specifically, the AMOC is highly correlated with sea and air temperatures of the central and eastern Mediterranean with a time lag of up to 2 years, while strong links are found with the entire Mediterranean's annual total precipitation up to 3 years ahead. The results suggest the possibility of predicting the occurrence of significantly extreme periods in the Mediterranean several months in advance. [ABSTRACT FROM AUTHOR]

Climate change (CC) has altered the hydrological cycle, mainly due to changes in temperature and precipitation, leading indirectly to regional water shortage issues, especially in the Mediterranean areas. The objective of this work was the investigation of the CC impact on water resources. Hydrological simulations under several CC scenarios were performed for the Vivari subbasin, located in the Eurotas river basin, Peloponnese, Greece. The analysis was carried out by applying the Thomas ABCD water balance model on a monthly basis, initially for the period between 2005 and 2009, to calibrate the model using available runoff measurements. Then, CC scenarios were incorporated into the model and the results are presented indicatively for three periods: a historic period (1970-2000), which was used as the reference period for comparisons; and two future periods: 2031-2060 and 2061-2090. Simulations for the three periods were based on freely available monthly precipitation and temperature timeseries, which were provided by the Data Extraction Application for Regional Climate (DEAR-Clima) web application tool. Results regarding average values, trends, and other statistics for monthly runoff are provided for the three periods and for several scenarios. [ABSTRACT FROM AUTHOR]

The sensitivity of the ICON model is gauged towards the establishment of ICON-LEPS in place of the currently operational COSMO-LEPS. A broad list of the model's parameters were tested over a domain covering the wider area of Greece and Italy in the year 2020. ICON model runs were performed on a 6.5 km horizontal grid and were enforced by the ECMWF operational forecast in 3 h intervals. The model's sensitivities were applied to several surface meteorological fields via their areal averages in the last (132nd) lead time hour of the model runs, when they were expected to be at their climax. It was found that there was a considerable impact regarding the minimum and maximum values for many of the examined parameters in reference to their default values, providing a valuable insight into the understanding of the ICON model in reference to previous works regarding the COSMO model. In addition, due to the extensive forecast period, a seasonal dependence with respect to the considered meteorological fields was displayed. These features are expected to be of major importance in deciding the most important parameters for the application of perturbation techniques in the ensemble process and methodology. [ABSTRACT FROM AUTHOR]

Climate change is a pressing global issue with significant impacts on human health. This study used a digital surveillance system on Twitter to investigate Greek-speaking users' sentiments and opinions regarding climate change's effects on human health. The study utilized a set of 61 keywords to collect 2.774 tweets from the last decade, which were manually analyzed for content and user type. The analysis revealed that news outlets mainly published informational tweets, whereas personal accounts expressed attitudes, opinions, perceptions, and beliefs. Moreover, the study found that Greek-speaking Twitter users are actively discussing climate change, particularly its consequences on their health. [ABSTRACT FROM AUTHOR]

As a significant component of natural climatic variability, teleconnection patterns play an important role in determining regional climate variability and extremes. The mechanisms linking the North Atlantic and the Mediterranean climate variability have not been rigorously demonstrated so far. Traditional statistical analysis of climate variability has vastly exploited concepts based on linear correlations and composites, nonetheless, with several weaknesses. The recently developed powerful concept of causal effect network (CEN) allows the detection of the causal relationships among a set of univariate time series (actors) by removing the confounding effects of autocorrelation, indirect links, and common drivers, retaining eventually only the actual causal links. In this study, we investigate the causal interaction mechanisms linking large-scale atmospheric variability with the Mediterranean winter climate by applying for the first time the CEN analysis. Results reveal causal links among the North Atlantic Oscillation (NAO), Eastern Mediterranean Pattern (EMP), and Eastern Atlantic (EA) teleconnection patterns, while the NAO acts as a causal driver for Mediterranean winter temperatures. [ABSTRACT FROM AUTHOR]

Windblown dust plays a crucial role in the Earth system, impacting climate, ecosystems, human activities, and health. The spatiotemporal evolution of dust plumes during transport is determined by wind, the primary driver of dust emission. In this study, we utilize outputs from the ECMWF-IFS, assimilating quality-assured Aeolus wind profiles, to initialize dust simulations with the WRF-Chem model. The aim is to assess the impact of Aeolus wind observations on modeling the desert dust cycle. Focusing on the ASKOS/JATAC campaign in September 2021 near Cabo Verde, we qualitatively and quantitatively evaluate the simulated dust-related outputs, revealing that even small differences in wind significantly affect the simulated dust emission rates and dust optical depth. [ABSTRACT FROM AUTHOR]

Heating and Cooling Degree Days (HDD, CDD) are indicative of the energy needs of buildings and also are associated with agriculturalism, tourism and other outdoor activities. Under the changing climate, future modifications of HDD and CDD are of primary importance. In the present work, monthly and annual HDD and CDD are computed and analyzed for the present and near future climate conditions. Elevation and sea proximity were found to be crucial in the formulation of energy requirements. Summer energy needs for cooling are expected to increase due to global warming while winter needs for heating are expected to decrease. [ABSTRACT FROM AUTHOR]

Wildfires are one of the strongest drivers of degradation of Mediterranean ecosystems, while weather and climate are among the main factors influencing fire potential. From this perspective, we attempt to assess the future forest fire risk in Crete in the near (2046-2065) and distant future (2081-2100), under the Representative Concentration Pathways (RCPs) of RCP2.6, RCP4.5, and RCP8.5. A risk assessment model was developed according to the conceptual framework of the "impact chain", as defined by the Intergovernmental Panel on Climate Change (IPCC), aiming at the formulation of a final composite risk index. The multicriteria spatial analysis, which was implemented with GIS techniques, highlighted the areas that are expected to be heavily affected in the future. It was found that the forest fire risk for the tourism sector increases with the higher emissions scenarios and towards the end of the century, with the south and central parts of the island exhibiting 'very high' risk. The effectiveness of this method is underlined, both in terms of implementing the necessary preventive measures against the adverse effects of climate change and of strengthening adaptation planning. [ABSTRACT FROM AUTHOR]

This study aims to provide insight regarding the future evolution of a series of important agroclimatic indicators for a specific farming area of viticulture in Stimagka, Greece. The calculated indicators cover various aspects of the climate and its impact on agriculture and can be categorized into four broad categories: temperature-, precipitation-, drought-, and animal comfort-related indicators. An ensemble of state-of-the-art regional climate model simulations with a spatial resolution of 12 km are used to calculate the indicators for the period 1986-2055. For the period 2006-2055, two scenarios of possible future evolution of anthropogenic greenhouse gases are used: rcp4.5 and rcp8.5. Results indicate a clear future increase in temperature-related indicators in the region and also more persistent drought conditions. [ABSTRACT FROM AUTHOR]

Climate change raises concerns over the sustainability of the outdoor thermal environment and its impacts on societies. This study aims to examine the thermal conditions in Athens metropolitan area, Greece. Hourly data from 15 stations of the Automatic Weather Station Network of the National Observatory of Athens (2010-2021) were used to estimate the Net Effective Temperature (NET) and the Universal Thermal Climate Index (UTCI). The NET and UTCI were higher within the Athens basin (NET: mean ± sd = 15.3 ± 7.1 °C; UTCI: mean ± sd = 18.9 ± 10.4 °C) than in the surrounding area (NET: mean ± sd = 11.2 ± 9.3 °C; UTCI: mean ± sd = 13.4 ± 13.4 °C; p < 0.001). The highest numbers of hours with unfavorable warm conditions were found in Faliro (28.6%, NET; 27.7%, UTCI), Neos Kosmos (28.6%, NET; 27.4%, UTCI) and Patissia (28.6%, NET; 27.2%, UTCI). With respect to unfavorable cool conditions, the highest number was in Spata (65.1%, NET; 28.4%, UTCI). [ABSTRACT FROM AUTHOR]

Surface solar radiation (SSR) is a crucial parameter for both the Earth's climate and human activities, and it consists of two components: the direct beam from the sun and diffuse radiation, with the latter being scattered by atmospheric molecules, aerosols, or clouds. The multidecadal variations of SSR, known as Global Dimming and Brightening (GDB), should also arise from a corresponding variability of either the direct or the diffuse radiation. Thus, the determination of the trends of both the direct and the diffuse radiation is important for showing the causes of GDB. In the present study, we estimate the trends of global and diffuse radiation on a global scale during the period 1984-2018, using worldwide reference ground-based measurements from the Global Energy Balance Archive (GEBA) and the Baseline Surface Radiation Network (BSRN). An increasing tendency of SSR is observed over most locations on our planet, while a decreasing trend occurs in India. On the other hand, the diffuse radiation has decreased over Europe and parts of Asia, whereas it has increased over the USA, India, and East Asia. [ABSTRACT FROM AUTHOR]