18 results
Search Results
2. The economic impact of climate change (CC) on the Greek economy.
- Author
-
Menegaki, Angeliki N., Tsounis, Nicholas, and Agiomirgianakis, George M.
- Subjects
CLIMATE change ,ECONOMIC impact ,TOURISM ,INPUT-output analysis ,DEMAND forecasting - Abstract
The considerable relevant size of the tourism sector for some economies, together with this sector's vulnerability to CC, renders this study an insightful aid to tourism demand forecasting. The paper applies a pooled mean group (PMG) model to identify climate parameters that affect tourism demand. Then, it continues with an input–output table analysis to show the transmission effects of CC on each component of the tourism sector. The PMG model imposes homogeneity on the long-run coefficients and while less restrictive, it is more efficient than other methods of the same family. The estimated gravity equation enables comparisons of the baseline scenario with various different scenarios of CC and finds how tourist arrivals could be affected up to 2080. Our results suggest that there is mostly a positive relationship of the squared difference of temperature and precipitation between Greece and tourist origin countries. Our findings also suggest that CC could lead to a fall in Greek GDP between 1.79 and 2.61%. We believe that our findings will help design appropriate policy actions that may offset or alleviate these negative future negative impacts of CC. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
3. Simulation and Evaluation of Water Resources Management Scenarios Under Climate Change for Adaptive Management of Coastal Agricultural Watersheds.
- Author
-
Lyra, Aikaterini and Loukas, Athanasios
- Subjects
WATER management ,SALTWATER encroachment ,COASTAL zone management ,WATERSHED management ,GROUNDWATER management ,CLIMATE change ,AGRICULTURE - Abstract
The main objective of this paper is to analyze the impact of climate change on water resources management and groundwater quantity and quality in the coastal agricultural Almyros Basin, in Greece. Intensive groundwater abstractions for irrigation and nitrogen fertilization for crop production maximization, have caused a large water deficit, nitrate pollution, as well as seawater intrusion in the Almyros aquifer system. Multi-model climate projections for Representative Concentration Pathways (RCPs 4.5 and 8.5) from the Med-CORDEX database for precipitation and temperature have been used to evaluate the impacts of climate change on the study area. The multi-model climate projections have been bias-corrected with Delta, Delta change of Mean and Variance, Quantile Delta Change, Quantile Empirical Mapping, and Quantile Gamma Mapping methods, and statistically tested to find the best GCM/RCM multi-model ensemble. Simulation of coastal water resources has been performed using an Integrated Modelling System (IMS) that contains connected models of surface hydrology (UTHBAL), groundwater hydrology (MODFLOW), nitrate leaching/crop growth (REPIC), nitrate pollution (MT3DMS), and seawater intrusion (SEAWAT). The results indicate that the best climate multi-model ensemble consists of three (3) climate models for both RCP4.5 and RCP8.5 using the Quantile Empirical Mapping bias-correction method. The IMS was applied for historical and future periods with observed and simulated meteorological inputs (e.g. precipitation and temperature) and various irrigation and agronomic scenarios and water storage works development (i.e. reservoirs). The results indicate that at least deficit irrigation and deficit irrigation along with rain-fed cultivation schemes, combined with or without the development and operation of reservoirs, should be applied to overcome the degradation of groundwater quality and quantity in the study basin. Based on the findings of this work, the water resources management should be adaptive to tackle the water resources problems of the Almyros Basin. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
4. The Nature-Based Solutions and climate change scenarios toward flood risk management in the greater Athens area—Greece.
- Author
-
Theochari, Aimilia-Panagiota and Baltas, Evangelos
- Subjects
CLIMATE change ,FLOOD risk ,GEOGRAPHIC information systems ,LAND cover ,WATERSHEDS - Abstract
This research paper focuses on implementing two Nature-Based Solutions (NBS) in the Sarantapotamos river basin upstream of Magoula settlement, evaluating their effectiveness through flood hydrograph calculations before and after NBS, and under future climate scenarios, encompassing lower, mean, and upper conditions representing ± 95%. The study area covers an area of 226 km
2 in Attica, Greece, susceptible to extreme flood events. The research contributes to NBS knowledge, emphasizing flood resilience and protecting settlements downstream. Land cover change and retention ponds, applied individually and combined, serve as NBS approaches. Flood hydrographs are calculated using the time–area (TA) diagram method in a geographic information system (GIS) with the Hydrological Engineering Center's Hydrological Modeling System (HEC-HMS). Results demonstrate NBS effectiveness in current climate conditions, reducing peak discharge by 9.3% and 28% for land cover change and retention ponds, respectively. The combined NBS achieves a 40.5% peak discharge reduction and a significant 15.7% total flood volume decrease. Under climate change scenarios, impacts on design precipitation and flood hydrographs vary. The upper climate change scenario exhibits a 3348% increase in peak discharge and a 600% rise in total flood volume, while the lower scenario sees a 44.6% reduction in total flood volume. In the mean climate change scenario, land cover change and retention ponds reduce peak discharge by 9.73% and 23.11% and total flood volume by 9.25% and 2.17%, respectively. In conclusion, retention ponds show substantial peak discharge reduction, while land cover changes extend the time to peak, emphasizing their potential in flood risk management. [ABSTRACT FROM AUTHOR]- Published
- 2024
- Full Text
- View/download PDF
5. Assessing the Vulnerability of a Deltaic Environment due to Climate Change Impact on Surface and Coastal Waters: The Case of Nestos River (Greece).
- Author
-
Skoulikaris, Charalampos, Makris, Christos, Katirtzidou, Margarita, Baltikas, Vasilios, and Krestenitis, Yannis
- Subjects
CLIMATE change ,IRRIGATION farming ,WATER supply ,TERRITORIAL waters ,WATER shortages ,IRRIGATION management ,WATER requirements for crops - Abstract
In deltaic areas, riverine and coastal waters interact; hence, these highly dynamic environments are particularly sensitive to climate change. This adds to existing anthropogenic pressures from irrigated agriculture, industrial infrastructure, urbanization, and touristic activities. The paper investigates the estimated future variations in the dynamics of surface and coastal water resources at a Mediterranean deltaic environment for the twenty-first century. Therefore, an Integrated Deltaic Risk Index (IDRI) is proposed as a vulnerability assessment tool to identify climate change impact (CCI) on the study area. For this purpose, three regional climate models (RCM) are used with representative concentration pathways (RCPs) 4.5 and 8.5 for short-term (2021–2050) and long-term (2071–2100) future periods. Extensive numerical modeling of river hydrology, storm surges, coastal inundation, water scarcity, and heat stress on irrigated agriculture is combined with available atmospheric data to estimate CCI on the Nestos river delta (Greece). The IDRI integrates modeling results about (i) freshwater availability covering agricultural demands for three water consumption scenarios, i.e., a reference (REF), a climate change (CC), and an extended irrigation (EXT) scenario, combining river discharges and hydropower dam operation; (ii) inundated coastal areas due to storm surges; and (iii) heat stress on cultivated crops. Sustainable practices on irrigated agriculture and established river basin management plans are also considered for the water demands under combinatory scenarios. The differentiations of model outputs driven by various RCM/RCP combinations are investigated. Increased deltaic vulnerability is found under the RCP8.5 scenario especially for the long-term future period. The projected IDRI demonstrates the need for integrated water resources management when compared with risk indexing of individual water processes in the study area. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
6. Implementing Crop Evapotranspiration in RDI for Farm-Level Drought Evaluation and Adaptation under Climate Change Conditions.
- Author
-
Tigkas, Dimitris, Vangelis, Harris, and Tsakiris, George
- Subjects
CLIMATE change ,DROUGHTS ,CROP yields ,CROP losses ,CROPS ,EVAPOTRANSPIRATION - Abstract
Agricultural drought is a natural hazard, often leading to significant crop yield losses and jeopardising food security. Climate change is anticipated to increase the duration and the magnitude of drought events, augmenting also their adverse effects. Recent studies, as well as policy initiatives, emphasise the need of proper farm-level management, for efficient mitigation of drought effects and adaptation to climate change. Towards this objective, robust, practical and comprehensible tools should be employed to support decision making process. In this paper, the Crop Reconnaissance Drought Index (CRDI) is introduced, aiming at assisting in agricultural drought analyses, focusing on specific crops. The proposed CRDI is an adjustment of the widely used Reconnaissance Drought Index (RDI), in which the utilised parameter of reference evapotranspiration is replaced by crop evapotranspiration. Along with this amendment, other issues regarding the calculation of CRDI are discussed, such as the selection of appropriate reference periods and methods of crop evapotranspiration assessment. The significance and the advantages of CRDI are illustrated through an application, considering different crops under Mediterranean conditions, in three regions of Greece. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
7. High resolution projections for extreme temperatures and precipitation over Greece.
- Author
-
Politi, Nadia, Vlachogiannis, D., Sfetsos, A., and Nastos, P. T.
- Subjects
METEOROLOGICAL research ,WEATHER forecasting ,TEMPERATURE - Abstract
The present study investigated future temperature and precipitation changes over Greece using the Weather Research and Forecasting (WRF) model. WRF was driven by EC-EARTH over Greece at very high resolution for the historical period (1980–2004), along with projected simulations, in the near future (2025–2049) and far future (2075–2099) under the Representative Concentration Pathways 4.5 (RCP4.5) and 8.5 (RCP8.5). Climatic variables were produced at 5-km grid spacing and 6-h interval. The historical simulation was evaluated against the available station observations. The analysis showed that the model underestimated the maximum temperatures and slightly overestimated the minimum temperatures. Also, the model simulated a small dry bias in precipitation with an excellent representation of the spatial patterns. The model projections for temperature under the two emission scenarios compared to the historical simulation revealed a robust magnitude of future warming with the most pronounced changes predominantly over the eastern areas of the country under the RCP8.5 in the far future. Projected precipitation changes were more evident in the far future with an overall decrease of the annual precipitation all over the eastern part of the country (with islands included) with the most dramatic reductions (above 40%) of seasonal precipitation observed under RCP8.5. Increases in the number of hot days were found everywhere with more pronounced changes over the plain areas under RCP8.5 in the far future. Significant increases of dry days were projected over the eastern part of the mainland and more intensely under RCP8.5 in the far future. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
8. The impact of climate change on tourism economies of Greece, Spain, and Turkey.
- Author
-
Du, Ding and Ng, Pin
- Subjects
TOURISM economics ,CLIMATE change ,TEMPERATURE measurements ,TOURISM ,TOURISM & the environment - Abstract
As major tourism economies in the Southern Mediterranean, Greece, Spain, and Turkey are particularly vulnerable to climate change. With mounting evidence of climate change, we study if the negative impact of climate change on Greece, Spain, and Turkey is particularly large. Empirically, we use a unique data set that makes temperature measurement more meaningful, and adopt the model in Ng and Zhao (Ecological Economics 70:963-970,
2011 ) to estimate the economic impacts of climate change on different types of economies. Our main finding is that climate change’s adverse impact on Greece, Spain, and Turkey is larger than its impacts on other types of economies, suggesting that Greece, Spain, and Turkey should engage in strong international cooperation to mitigate the adverse impact of climate change. [ABSTRACT FROM AUTHOR]- Published
- 2018
- Full Text
- View/download PDF
9. Spatial Resilience to Wildfires through the Optimal Deployment of Firefighting Resources: Impact of Topography on Initial Attack Effectiveness.
- Author
-
Sakellariou, Stavros, Sfougaris, Athanassios, Christopoulou, Olga, and Tampekis, Stergios
- Subjects
WILDFIRE prevention ,FIREFIGHTING ,TRAVEL time (Traffic engineering) ,WILDFIRES ,TOPOGRAPHY ,FOREST fires ,CLIMATE change - Abstract
Strongly affected by the escalating impacts of climate change, wildfires have been increasing in frequency and severity around the world. The primary aim of this study was the development of specific territorial measures—estimating the optimal locations of firefighting resources—to enhance the spatial resilience to wildfires in the fire-prone region of Chalkidiki Prefecture in northern Greece. These measures focus on the resistance to wildfires and the adaptation of strategies to wildfire management, based on the estimation of burn probability, including the effect of anthropogenic factors on fire ignition. The proposed location schemes of firefighting resources such as vehicles consider both the susceptibility to fire and the influence of the topography on travel simulation, highlighting the impact of road slope on the initial firefighting attack. The spatial scheme, as well as the number of required firefighting forces is totally differentiated due to slope impact. When we ignore the topography effect, a minimum number of fire vehicles is required to achieve the maximization of coverage (99.2% of the entire study area) giving priority to the most susceptible regions (that is, employing 18 of 24 available fire vehicles). But when we adopt more realistic conditions that integrate the slope effect with travel time, the model finds an optimal solution that requires more resources (that is, employing all 24 available fire vehicles) to maximize the coverage of the most vulnerable regions within 27 min. This process achieves 80% of total coverage. The proposed methodology is characterized by a high degree of flexibility, and provides optimized solutions to decision makers, while considering key factors that greatly affect the effectiveness of the initial firefighting attack. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
10. An assessment of climate change impact on air masses arriving in Athens, Greece.
- Author
-
Karozis, S., Sfetsos, A., Gounaris, N., and Vlachogiannis, D.
- Subjects
AIR masses ,CLIMATE change ,ATMOSPHERIC boundary layer ,CLIMATOLOGY ,SEA level - Abstract
Climate change is inherently linked to long-term non-stationary changes in the characteristics and frequency of weather patterns. The present study attempts to identify the statistical changes of weather patterns in Athens Greece, from the comparative assessment of 96-h backward trajectories between historic (1980–2009) and future (2020–2049) climatology derived from the IPCC RCP4.5 and RCP8.5 scenarios. Arrival heights at 750 m, 1500 m, and 3000 m above sea level are considered to account for the impact of the planetary boundary layer and the lower free troposphere. The analysis of the historic period yields 7 dominant patterns for all heights determined independently, with similar spatial characteristics but varying frequency of occurrence. The classification of backward trajectories under future climate using the same historic clusters reveals percentage changes from locally short-distance travelling patterns to longer-distance ones with a predominant northbound direction. As a second experiment, backward trajectories are re-clustered independently reaching again the same type of clusters but with observable changes in the cluster origins and trajectory lengths. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
11. The Carbon Footprint of Transport Activities of the 401 Military General Hospital of Athens.
- Author
-
Bozoudis, Vasileios and Sebos, Ioannis
- Subjects
MILITARY hospitals ,ECOLOGICAL impact ,GREENHOUSE gas mitigation ,HEALTH facilities ,PATIENT-professional relations ,MEDICAL waste disposal - Abstract
It is a scientifically accepted fact that climate change constitutes a major challenge for the future well-being of the whole humanity. Medical and hospital care facilities generate their own greenhouse emissions. Hospital transportation activities encompass not only the transportation of patients and medical personnel but also the operation of transportation assets associated with the logistical support of hospital operations. The present research focuses on the carbon footprint of the transportation functions and activities of the 401 Military General Hospital of Athens (401 MGHA), in order to serve as a starting point for the development of an action plan for the mitigation of greenhouse gas emissions in the hospital-based healthcare of the Hellenic (Greek) Army. Based on this, a simple and easily operated monitoring scheme of the greenhouse gas emissions of the transport activities and a portfolio of mitigation actions are proposed. The estimation of the carbon footprint of the transport activities, and of the other stationary emission sources of the hospital (energy consumption, waste treatment, etc.) of the 401 MGHA, will be the starting point for the development of an action plan for the estimation and mitigation of GHG emissions in the hospital-based healthcare of Greece. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
12. The impacts of climate change on Greek airports.
- Author
-
Gratton, Guy, Padhra, Anil, Rapsomanikis, Spyridon, and Williams, Paul D.
- Subjects
CLIMATE change ,NOISE pollution ,AIRPORTS ,RUNWAYS (Aeronautics) ,AIRBUS A320 ,TEMPERATURE effect ,AIRLINE industry - Abstract
Time series of meteorological parameters at ten Greek airports since 1955 indicated the level of climate change in the Eastern Mediterranean area. Using this data, take-off performance was analysed for the DHC-8-400—a typical short range turboprop airliner, and the A320, a typical medium scale turbofan airliner. For airports with longer runways, a steady but unimportant increase in take-off distances was found. For airports with shorter runways, the results indicate a steady reduction in available payload. At the most extreme case, results show that for an Airbus A320, operating from the, relatively short, 1511m runway at Chios Airport, the required reduction in payload would be equivalent to 38 passengers with their luggage, or fuel for 700 nautical miles (1300 km) per flight, for the period between the A320's entry to service in 1988 and 2017. These results indicate that for airports where aeroplane maximum take-off mass is a performance limited function of runway length, and where minimum temperatures have increased and/or mean headwind components decreased, climate change has already had a marked impact on the economic activity in the airline industry. Similar analyses could be usefully carried out for other runway-length–limited airports, which may often include island airports. It is also noted that previous research has only considered temperature effects, and not wind effects. Wind effects in this study are less significant than temperature, but nonetheless have an effect on both field performance noise and pollution nuisance around airports. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
13. Integrated Assessment of Natural Hazards, Including Climate Change's Influences, for Cultural Heritage Sites: The Case of the Historic Centre of Rethymno in Greece.
- Author
-
Ravankhah, Mohammad, de Wit, Rosmarie, Argyriou, Athanasios V., Chliaoutakis, Angelos, Revez, Maria João, Birkmann, Joern, Žuvela-Aloise, Maja, Sarris, Apostolos, Tzigounaki, Anastasia, and Giapitsoglou, Kostas
- Subjects
HISTORIC sites ,TSUNAMI hazard zones ,CULTURAL property ,CLIMATE change ,RISK assessment ,EMERGENCY management - Abstract
Within the framework of disaster risk management, this article proposes an interdisciplinary method for the analysis of multiple natural hazards, including climate change's influences, in the context of cultural heritage. A taxonomy of natural hazards applicable to cultural heritage was developed based on the existing theoretical and conceptual frameworks. Sudden-onset hazards, such as earthquakes and floods, and slow-onset hazards, such as wetting–drying cycles and biological contamination, were incorporated into the hazard assessment procedure. Future alteration of conditions due to climate change, such as change in heat waves' duration, was also taken into account. The proposed hazard assessment framework was applied to the case of the Historic Centre of Rethymno, a city on the northern coast of the island of Crete in Greece, to identify, analyze, and prioritize the hazards that have the potential to cause damage to the center's historic structures. The assessment procedure includes climate model projections, GIS spatial modeling and mapping, and finally a hazard analysis matrix to enable the sharing of a better understanding of multiple hazards with the stakeholders. The results can facilitate decision making by providing the vulnerability and risk analysis with the nature and spatial distribution of the significant hazards within the study area and its setting. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
14. Last glacial geomorphologic records in Mt Chelmos, North Peloponnesus, Greece.
- Author
-
Pavlopoulos, Kosmas, Leontaritis, Aris, Athanassas, Constantin D., Petrakou, Chara, Vandarakis, Dimitris, Nikolakopoulos, Kosnstantinos, Stamatopoulos, Leonidas, and Theodorakopoulou, Katherina
- Subjects
GLACIAL landforms ,MOUNTAINS ,CLIMATE change ,PALEOCLIMATOLOGY ,PLEISTOCENE paleoclimatology ,REMOTE-sensing images - Abstract
This study deals with the analysis of the glacial processes that have affected the relief of Mt Chelmos in northern Peloponnesus, Greece during middle and Late Pleistocene. The goal was to compile a combined geomorphological-geological map of the study area which would enable the chronological stratification of the glacial landforms cropping up on Mt. Chelmos. Chronological stratification was further aided by optically stimulated luminescence (OSL) dating. The map served as the basis upon which the reconstruction and discussion on the phases of the Middle-Late Quaternary paleoclimatic history of Mt. Chelmos have been made. A sophisticated semiautomated method was first used to analyze the Digital Elevation Model (DEM), combined with Aster, Quickbird and ALOS imagery in order to identify glacial and periglacial, as well as karstic features. Then, these features along with other nonrecognizable features from the remote-sensing images were documented in the field. In this way, several glacial landforms were identified, such as moraines and cirques, indicating extended glaciation phases during the middle and Late Pleistocene. Additionally, a ground moraine located at an altitude of 1900-2050 m, within the Spanolakos glacial valley, was dated using the OSL-dating method. The resulting ages indicate a phase of glacier advance/stabilization during MIS-5b (89-86 ka), which is in consistence with pollenrecord evidence from Greece and the Mediterranean. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
15. On the association of aerosol optical depth and total ozone fluctuations with recent earthquakes in Greece.
- Author
-
Varotsos, Costas, Efstathiou, Maria., and Cracknell, Arthur.
- Subjects
ATMOSPHERIC aerosols ,OZONE ,EARTHQUAKES ,TIME series analysis ,CLIMATE change - Abstract
A number of recent studies suggest that atmospheric changes that precede an earthquake might offer the hope of providing early warning. This study attempts to examine seismo-atmospheric anomalies around the time and the location of some of the major earthquakes in Greece in the period 2001-2015. Daily values of aerosol optical depth (AOD) and total ozone column (TOZ) obtained from satellite observations are used, in the time window between 25 days before and 14 days after each of these events, in a 1° × 1° area centred on the epicentre of each earthquake. For some of these earthquake events, abnormal increases in time series of AOD and TOZ data were detected before and after the occurrence of the earthquake. Nevertheless, in other cases, no clear anomalies were observed around the earthquake date. In addition, examining the statistics of AOD and TOZ daily values, there were many cases of prominent abnormal variations, without, however, being associated with an earthquake event. Therefore, no clear association was found between AOD and TOZ fluctuations and recent earthquakes in Greece. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
16. Impact of irrigation scenarios and precipitation projections on the groundwater resources of Viannos Basin at the island of Crete, Greece.
- Author
-
Varouchakis, Emmanouil, Karatzas, George, and Giannopoulos, George
- Subjects
IRRIGATION ,METEOROLOGICAL precipitation ,GROUNDWATER ,CLIMATE change research ,HYDROGEOLOGY - Abstract
Recent climate change studies for the Mediterranean region have projected the near future temperature and precipitation trends. The increasing water demands for human consumption and agricultural purposes, as well as the potential overexploitation of the groundwater resources, in combination with the climatic projections are expected to affect the groundwater resources of the Mediterranean hydrological basins. This work focuses on the Viannos alluvial basin at the island of Crete, Greece. It considers primarily the increasing water demands for irrigation in the area of interest and the projected precipitation trend in the next five hydrological years for the island of Crete. The groundwater system is simulated based on the current hydrological/hydrogeological conditions of the basin and based on anticipated hydrological events. Scenarios concerning future precipitation trends and pumping schemes at existing wells are examined to assess the near-future stresses on the basin groundwater resources. Groundwater flow modeling is performed using the Visual Modflow software. Based on the study of different scenarios modeling results show that the aquifer is primarily affected during the dry period of the hydrological year. However, sufficiently replenishment is observed during the wet period as the highest water table drop is 0.65 m at the end of the 5 years modelling period. Therefore, the aquifer is not expected to face serious problems in the near future from the increased irrigation demands and from the short-term projected precipitation trends. Simulations for 10 and 20-year periods following the precipitation projections and the specified pumping schemes also show that the aquifer resources are not expected to be significantly affected. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
17. Modeling and mapping temperature and precipitation climate data in Greece using topographical and geographical parameters.
- Author
-
Feidas, Haralambos, Karagiannidis, Athanasios, Keppas, Stavros, Vaitis, Michail, Kontos, Themistoklis, Zanis, Prodromos, Melas, Dimitrios, and Anadranistakis, Emmanouil
- Subjects
METEOROLOGICAL precipitation ,DIGITAL elevation models ,NORMALIZED difference vegetation index ,ATMOSPHERIC temperature ,CLIMATE change - Abstract
This study presents a methodology for modeling and mapping the seasonal and annual air temperature and precipitation climate normals over Greece using several topographical and geographical parameters. Data series of air temperature and precipitation from 84 weather stations distributed evenly over Greece are used along with a set of topographical and geographical parameters extracted with Geographic Information System methods from a digital elevation model (DEM). Normalized difference vegetation index (NDVI) obtained from MODIS Aqua satellite data is also used as a geographical parameter. First, the relation of the two climate elements to the topographical and geographical parameters was investigated based on the Pearson's correlation coefficient to identify the parameters that mostly affect the spatial variability of air temperature and precipitation over Greece. Then a backward stepwise multiple regression was applied to add topographical and geographical parameters as independent variables into a regression equation and develop linear estimation models for both climate parameters. These models are subjected to residual correction using different local interpolation methods, in an attempt to refine the estimated values. The validity of these models is checked through cross-validation error statistics against an independent test subset of station data. The topographical and geographical parameters used as independent variables in the multiple regression models are mostly those found to be strongly correlated with both climatic variables. Models perform best for annual and spring temperatures and effectively for winter and autumn temperatures. Summer temperature spatial variability is rather poorly simulated by the multiple regression model. On the contrary, best performance is obtained for summer and autumn precipitation while the multiple regression model is not able to simulate effectively the spatial distribution of spring precipitation. Results revealed also a relatively weaker model performance for precipitation than that for air temperature probably due to the highly variable nature of precipitation compared to the relatively low spatial variability of air temperature field. The correction of the developed regression models using residuals improved though not significantly the interpolation accuracy. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
18. Identifying potential effects of climate change on the development of water resources in Pinios River Basin, Central Greece.
- Author
-
Arampatzis, G., Panagopoulos, A., Pisinaras, V., Tziritis, E., and Wendland, F.
- Subjects
CLIMATE change ,GENERAL circulation model ,CIRCULATION models ,WATER resources development - Abstract
The aim of the present study is to assess the future spatial and temporal distribution of precipitation and temperature, and relate the corresponding change to water resources’ quantitative status in Pinios River Basin (PRB), Thessaly, Greece. For this purpose, data from four Regional Climate Models (RCMs) for the periods 2021-2100 driven by several General Circulation Models (GCMs) were collected and bias-correction was performed based on linear scaling method. The bias-correction was made based on monthly precipitation and temperature data collected for the period 1981-2000 from 57 meteorological stations in total. The results indicate a general trend according to which precipitation is decreasing whilst temperature is increasing to an extent that varies depending on each particular RCM-GCM output. On the average, annual precipitation change for the period 2021-2100 was about − 80 mm, ranging between − 149 and + 35 mm, while the corresponding change for temperature was 2.81 °C, ranging between 1.48 and 3.72 °C. The investigation of potential impacts to the water resources demonstrates that water availability is expected to be significantly decreased in the already water-stressed PRB. The water stresses identified are related to the potential decreasing trend in groundwater recharge and the increasing trend in irrigation demand, which constitutes the major water consumer in PRB. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.