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Sample records for greece synoptic conditions

  1. Analysis of synoptic conditions for tornadic days over western Greece

    NASA Astrophysics Data System (ADS)

    Nastos, P. T.; Matsangouras, I. T.

    2014-09-01

    Tornadoes have been reported in Greece during the last few decades and recent studies have given evidence that western Greece is an area vulnerable to tornadoes, waterspouts and funnel clouds In this study, the composite means and anomalies of synoptic conditions for tornadic events (tornadoes, waterspouts and funnel clouds) over western Greece are analyzed and discussed. The daily composite means of synoptic conditions were based on the National Centers for Environmental Prediction-National Center for Atmospheric Research (NCEP-NCAR) reanalysis data sets, for the period 12 August 1953 to 31 December 2012. The daily composite anomalies were calculated with respect to 30 years of climatological study (1981-2010) of the synoptic conditions. The analysis was carried out in terms of seasonal and monthly variability of composite means and anomalies of synoptic conditions for specific isobaric levels of 500, 700, 850, 925 hPa and the sea level pressure (SLP). In addition, an analysis and discussion about the dynamic lifted index from NCEP-NCAR reanalysis data sets is presented. The daily composite mean analysis of 500 hPa revealed a trough line across the northern Adriatic Sea and central Italy, associated with a SW upper-air stream over western Greece. The maximum composite anomalies were depicted at the isobaric level of 500 hPa during autumn, spring and summer, against winter when the anomaly appeared at 925 hPa isobaric level. In addition, 48% of tornado events during the autumn season occurred in pre-frontal weather conditions (cold fronts) and 27% developed after the passage of the cold front. Furthermore, the main difference in synoptic patterns between tornado and waterspout days along western Greece during the autumn season is the maximum daily composite anomaly over the Gulf of Taranto.

  2. Analysis of synoptic conditions for tornadic days over Western Greece

    NASA Astrophysics Data System (ADS)

    Nastos, P. T.; Matsangouras, I. T.

    2014-03-01

    Tornadoes have been reported in Greece during the last decades and recent studies have given evidence that west Greece is a vulnerable area for tornadoes, waterspouts and funnel clouds to occur. In this study, the composite means and anomalies of synoptic conditions for tornadic events (tornadoes, waterspouts and funnel clouds) over west Greece are analyzed and discussed. The daily composite means of synoptic conditions were based on National Centers for Environmental Prediction-National Center for Atmospheric Research (NCEP/NCAR) reanalysis datasets, for the period 12 August 1953 to 31 December 2012. The daily composite anomalies were calculated with respect to 30 years climatology (1981-2010) of the synoptic conditions. The analysis was carried out in terms of seasonal and monthly variability of composite means and anomalies of synoptic conditions for specific isobaric levels of 500, 700, 850, 925 hPa and the sea level pressure (SLP). In addition, an analysis and discussion about the dynamic Lifted Index from NCEP/NCAR Reanalysis datasets is presented.

  3. Comparative analysis of near-present and future synoptic conditions and their contribution to precipitation in central Greece

    NASA Astrophysics Data System (ADS)

    Karacostas, Theodore S.; Bampzelis, Dimitrios; Karipidou, Symela; Pytharoulis, Ioannis; Tegoulias, Ioannis; Kartsios, Stergios; Kotsopoulos, Stylianos; Pakalidou, Nikoletta

    2015-04-01

    The objective on this study is to identify and categorize the daily synoptic circulation patterns encountered between the two periods, in near-present (2001-2010) and future (2041-2050), over the greater area of central and northern Greece, under the "DAPHNE" project (www.daphne-meteo.gr). The followed up statistical analyses and comparisons are focus on the demonstration of the differences in the frequency of occurrences of the synoptic situations between the two time periods, aiming at mitigating drought in central Greece by means of Weather Modification. Actually, within the context of the project, the daily synoptic circulation patterns encountered during the near-present ten-year period are identified and classified according to Karacostas et al. (1992) synoptic classification, into ten distinct synoptic conditions, based on the isobaric level of 500hPa. A similar procedure is adopted for the future period 2041-2050, by developing the mid-tropospheric synoptic circulation patterns through the RegCM3 regional climate model, under the IPCC scenario A1B. Results indicate that certain differences exist between near-present and future frequency distribution of occurrences of the synoptic situations over the study area. The northwest (NW) and southwest (SW) synoptic circulation patterns remain the most frequent synoptic conditions observed for both examined periods. The low pressure system activity over the area exhibit significant decrease during the future period, as it is depicted from the inter-comparison of the frequencies of the closed low (L-2) and cut-off low (L-3) systems. On the other hand, the unorganized synoptic conditions, which are mostly identified as high-low patterns (H-L), appear to increase considerably. The frequencies of zonal flow (ZON) and those of synoptic conditions associated with the presence of high-pressure system over the area, that is (H-1) and (H-2), remain almost unchanged between the two periods. The impact of the aforementioned

  4. Study of the tornado event in Greece on March 25, 2009: Synoptic analysis and numerical modeling using modified topography

    NASA Astrophysics Data System (ADS)

    Matsangouras, I. T.; Nastos, P. T.; Pytharoulis, I.

    2016-03-01

    Recent research revealed that western Greece and NW Peloponnese are regions that favor prefrontal tornadic incidence. On March 25, 2009 a tornado developed approximately at 10:30 UTC near Varda village (NW Peloponnese). Tornado intensity was T4-T5 (TORRO scale) and consequently caused an economic impact of 350,000 € over the local society. The goals of this study are: (i) to analyze synoptic and remote sensing features regarding the tornado event over NW Peloponnese and (ii) to investigate the role of topography in tornadogenesis triggered under strong synoptic scale forcing over that area. Synoptic analysis was based on the European Centre for Medium-Range Weather Forecasts (ECMWF) data sets. The analysis of daily anomaly of synoptic conditions with respect to 30 years' climatology (1981-2010), was based on the National Centers for Environmental Prediction-National Center for Atmospheric Research (NCEP-NCAR) reanalysis data sets. In addition, numerous remote sensing data sets were derived by the Hellenic National Meteorological Service (HNMS) weather station network in order to better interpret the examined tornado event. Finally, numerical modeling was performed using the non-hydrostatic Weather Research and Forecasting model (WRF), initialized by ECMWF gridded analyses, with telescoping nested grids that allow the representation of atmospheric circulations ranging from the synoptic scale down to the meso-scale. The two numerical experiments were performed on the basis of: (a) the presence and (b) the absence of topography (landscape), so as to determine whether the occurrence of a tornado - identified by diagnostic instability indices - could be indicated by modifying topography. The energy helicity index (EHI), the bulk Richardson number (BRN) shear, the storm-relative environmental helicity (SRH), and the maximum convective available potential energy (MCAPE, for parcels with maximum θe) were considered as principal diagnostic instability variables and

  5. Groundwater quality of porous aquifers in Greece: a synoptic review

    NASA Astrophysics Data System (ADS)

    Daskalaki, P.; Voudouris, K.

    2008-04-01

    Greece is dependent on groundwater resources for its water supply. The main aquifers are within carbonate rocks (karstic aquifers) and coarse grained Neogene and Quaternary deposits (porous aquifers). The use of groundwater resources has become particularly intensive in coastal areas during the last decades with the intense urbanization, tourist development and irrigated land expansion. Sources of groundwater pollution are the seawater intrusion due to over-exploitation of coastal aquifers, the fertilizers from agricultural activities and the disposal of untreated wastewater in torrents or in old pumping wells. In the last decades the total abstractions from coastal aquifers exceed the natural recharge; so the aquifer systems are not used safely. Over-exploitation causes a negative water balance, triggering seawater intrusion. Seawater intrusion phenomena are recorded in coastal aquifer systems. Nitrate pollution is the second major source of groundwater degradation in many areas in Greece. The high levels of nitrate are probably the result of over-fertilization and the lack of sewage systems in some urban areas.

  6. Synoptic conditions and hazards in coastal zone

    NASA Astrophysics Data System (ADS)

    Surkova, Galina; Arkhipkin, Victor; Kislov, Alexsandr

    2013-04-01

    This work is an approach to the methodology of prediction of hazards in the coastal zone. For the past 60 years, according to the observations and reanalysis, meteorological conditions are rough in connection with the storm waves and strong winds resulting in catastrophic damage in the coastal zone of the Black and Caspian Seas. Forecast of similar events is taken from CMIP3 modeled for the future climate 2046-2065 by general global atmosphere and ocean circulation model MPI-ECHAM5. The research was conducted for the three types of calendar data samples: 1) storm wave and surge from observations (1948-2012), 2) storm simulations with wave height of 4 m and more (1948-2010), and 3) prognostic climate scenarios for 2046-2065. In the first sample especially rare events were chosen, accompanied by a large damage in the coastal zone. Second sample of cases was derived from modeling of SWAN (Simulating WAves Nearshore). The third sample was derived from projections of cases from group 1 in the MPI-ECHAM5 climate forecasts for 2046-2065. For each sample the data of large-scale fields of surface pressure, height 500 hPa isobaric surfaces, 700gPa (Reanalysis NCEP / NCAR) was analyzed. On the basis of statistical techniques (decomposition of fields in the natural orthogonal functions (EOF) and cluster analysis) the synoptic situations associated with these events were classified. Centroids of pressure fields for dominated cases show that there are two basic types of synoptic situations in case of storm waves for the Black Sea. In the first case main role play the Mediterranean cyclones located in the east of the Mediterranean Sea, they are spread over the Black Sea, and often form a local center of low pressure. Their movement is blocked by the high pressure over the European Russia and Eastern Europe. If the center of the cyclone is over Asia and the southern part of the Black Sea, the weather is dominated by the north-eastern, eastern, south-easterly winds. In some cases

  7. Synoptic-mesoscale analysis and numerical modeling of a tornado event on 12 February 2010 in northern Greece

    NASA Astrophysics Data System (ADS)

    Matsangouras, I. T.; Nastos, P. T.; Pytharoulis, I.

    2011-07-01

    Tornadoes are furious convective weather phenomena, with the maximum frequency over Greece during the cold period (autumn, winter).This study analyzes the tornado event that occurred on 12 February 2010 near Vrastama village, at Chalkidiki's prefecture, a non urban area 45 km southeast of Thessaloniki in northern Greece. The tornado developed approximately between 17:10 and 17:35 UTC and was characterized as F2 (Fujita Scale). The tornado event caused several damages to an industrial building and at several olive-tree farms. A synoptic survey is presented along with satellite images, radar products and vertical profile of the atmosphere. Additionally, the nonhydrostatic WRF-ARW atmospheric numerical model (version 3.2.0) was utilized in analysis and forecast mode using very high horizontal resolution (1.333 km × 1.333 km) in order to represent the ambient atmospheric conditions. A comparison of statistical errors between WRF-ARW forecasts and ECMWF analysis is presented, accompanied with LGTS 12:00 UTC soundings (Thessaloniki Airport) and forecast soundings in order to verify the WRF-ARW model. Additionally, a comparison between WRF-ARW and ECMWF thermodynamic indices is also presented. The WRF-ARW high spatial resolution model appeared to simulate with significant accuracy a severe convective event with a lead period of 18 h.

  8. Synoptic-mesoscale analysis and numerical modeling of a tornado event on 12 February 2010 in northern Greece

    NASA Astrophysics Data System (ADS)

    Matsangouras, J. T.; Nastos, P. T.; Pytharoulis, I.

    2010-09-01

    Tornadoes are furious convective weather phenomena, having increased frequency, particularly in the cool season, attributed to the higher moisture content of the atmosphere due to global warming. Tornadoes' source regions are more likely shallow waters, which are easily warmed, such as Gulf of Mexico or Mediterranean Sea. This study analyzes the tornado event, that occurred on 12 February 2010 in Vrastera, Chalkidiki, a non urban area 45 km southeastern of Thessaloniki in northern Greece. The tornado was developed approximately between 17:15 and 18:45 UTC and characterized as F2 (Fujita Scale). The tornado caused several damages to an industrial building and an olive-tree farm. A synoptic analysis based on the ECMWF charts is presented along with an extended dataset of satellite images, radar products and vertical profile of the atmosphere. Additionaly, the nonhydrostatic WRF-ARW atmospheric numerical model (version 3.2) was utilized in analysis and forecast mode using very high horizontal resolution (1 km x 1 km) in order to represent the ambient atmospheric conditions and examine the prediction of the event. Sensitivity experiments look into the model performance in the choice of microphysical and boundary layer parameterization schemes.

  9. Evaluation of operational numerical weather predictions in relation to the prevailing synoptic conditions

    NASA Astrophysics Data System (ADS)

    Pytharoulis, Ioannis; Tegoulias, Ioannis; Karacostas, Theodore; Kotsopoulos, Stylianos; Kartsios, Stergios; Bampzelis, Dimitrios

    2015-04-01

    The Thessaly plain, which is located in central Greece, has a vital role in the financial life of the country, because of its significant agricultural production. The aim of DAPHNE project (http://www.daphne-meteo.gr) is to tackle the problem of drought in this area by means of Weather Modification in convective clouds. This problem is reinforced by the increase of population and the water demand for irrigation, especially during the warm period of the year. The nonhydrostatic Weather Research and Forecasting model (WRF), is utilized for research and operational purposes of DAPHNE project. The WRF output fields are employed by the partners in order to provide high-resolution meteorological guidance and plan the project's operations. The model domains cover: i) Europe, the Mediterranean sea and northern Africa, ii) Greece and iii) the wider region of Thessaly (at selected periods), at horizontal grid-spacings of 15km, 5km and 1km, respectively, using 2-way telescoping nesting. The aim of this research work is to investigate the model performance in relation to the prevailing upper-air synoptic circulation. The statistical evaluation of the high-resolution operational forecasts of near-surface and upper air fields is performed at a selected period of the operational phase of the project using surface observations, gridded fields and weather radar data. The verification is based on gridded, point and object oriented techniques. The 10 upper-air circulation types, which describe the prevailing conditions over Greece, are employed in the synoptic classification. This methodology allows the identification of model errors that occur and/or are maximized at specific synoptic conditions and may otherwise be obscured in aggregate statistics. Preliminary analysis indicates that the largest errors are associated with cyclonic conditions. Acknowledgments This research work of Daphne project (11SYN_8_1088) is co-funded by the European Union (European Regional Development Fund

  10. Synoptic drivers of 400 years of summer temperature and precipitation variability on Mt. Olympus, Greece

    NASA Astrophysics Data System (ADS)

    Klesse, Stefan; Ziehmer, Malin; Rousakis, Georgios; Trouet, Valerie; Frank, David

    2015-08-01

    The Mediterranean region has been identified as a global warming hotspot, where future climate impacts are expected to have significant consequences on societal and ecosystem well-being. To put ongoing trends of summer climate into the context of past natural variability, we reconstructed climate from maximum latewood density (MXD) measurements of Pinus heldreichii (1521-2010) and latewood width (LWW) of Pinus nigra (1617-2010) on Mt. Olympus, Greece. Previous research in the northeastern Mediterranean has primarily focused on inter-annual variability, omitting any low-frequency trends. The present study utilizes methods capable of retaining climatically driven long-term behavior of tree growth. The LWW chronology corresponds closely to early summer moisture variability (May-July, r = 0.65, p < 0.001, 1950-2010), whereas the MXD-chronology relates mainly to late summer warmth (July-September, r = 0.64, p < 0.001; 1899-2010). The chronologies show opposing patterns of decadal variability over the twentieth century (r = -0.68, p < 0.001) and confirm the importance of the summer North Atlantic Oscillation (sNAO) for summer climate in the northeastern Mediterranean, with positive sNAO phases inducing cold anomalies and enhanced cloudiness and precipitation. The combined reconstructions document the late twentieth—early twenty-first century warming and drying trend, but indicate generally drier early summer and cooler late summer conditions in the period ~1700-1900 CE. Our findings suggest a potential decoupling between twentieth century atmospheric circulation patterns and pre-industrial climate variability. Furthermore, the range of natural climate variability stretches beyond summer moisture availability observed in recent decades and thus lends credibility to the significant drying trends projected for this region in current Earth System Model simulations.

  11. Synoptic drivers of 400 years of summer temperature and precipitation variability on Mt. Olympus, Greece

    NASA Astrophysics Data System (ADS)

    Klesse, Stefan; Ziehmer, Malin; Rousakis, Georgios; Trouet, Valerie; Frank, David

    2014-09-01

    The Mediterranean region has been identified as a global warming hotspot, where future climate impacts are expected to have significant consequences on societal and ecosystem well-being. To put ongoing trends of summer climate into the context of past natural variability, we reconstructed climate from maximum latewood density (MXD) measurements of Pinus heldreichii (1521-2010) and latewood width (LWW) of Pinus nigra (1617-2010) on Mt. Olympus, Greece. Previous research in the northeastern Mediterranean has primarily focused on inter-annual variability, omitting any low-frequency trends. The present study utilizes methods capable of retaining climatically driven long-term behavior of tree growth. The LWW chronology corresponds closely to early summer moisture variability (May-July, r = 0.65, p < 0.001, 1950-2010), whereas the MXD-chronology relates mainly to late summer warmth (July-September, r = 0.64, p < 0.001; 1899-2010). The chronologies show opposing patterns of decadal variability over the twentieth century (r = -0.68, p < 0.001) and confirm the importance of the summer North Atlantic Oscillation (sNAO) for summer climate in the northeastern Mediterranean, with positive sNAO phases inducing cold anomalies and enhanced cloudiness and precipitation. The combined reconstructions document the late twentieth—early twenty-first century warming and drying trend, but indicate generally drier early summer and cooler late summer conditions in the period ~1700-1900 CE. Our findings suggest a potential decoupling between twentieth century atmospheric circulation patterns and pre-industrial climate variability. Furthermore, the range of natural climate variability stretches beyond summer moisture availability observed in recent decades and thus lends credibility to the significant drying trends projected for this region in current Earth System Model simulations.

  12. Tropical Plumes over the Middle East: Climatology and synoptic conditions

    NASA Astrophysics Data System (ADS)

    Tubi, Amit; Dayan, Uri

    2014-08-01

    A 10-yr climatological study of Tropical Plumes (TPs) observed over the Middle East was undertaken. Several tools were used to identify and analyze these mid-tropospheric elongated cloudbands: satellite images, reanalysis and radiosonde data, backward trajectories, and cluster analysis. In order to conduct an in-depth examination of the synoptic conditions controlling this tropical-extratropical phenomenon, a dual methodology was adopted. In the first analysis, the identified 45 plumes were classified to precipitative and non-precipitative. In the second analysis, backward trajectories of the plumes were clustered in order to detect their moisture origins and pathways. In addition to the well documented south-western plumes originating in West Africa, a more southern pathway was identified, in which moisture was transported from Central to East African sources. The ‘south-western’ plumes are associated with a southwards penetration of mid-latitude troughs, associated with an intensified thermal wind and a longer jet streak, extending as far as Northwestern Africa. In the ‘southern’ category the Sub-Tropical Jet is associated with an anticyclonic flow over the south of the Arabian Peninsula, serving as an essential vehicle advecting moisture from tropical origins. This moisture pathway is considerably shorter than the south-western one. Several conditions favor precipitation induced by TPs over the domain: a northward migration of the jet streak resulting in a weakening of the wind speed over the target area, a deeper trough at the 500 hPa level and a shorter moisture corridor.

  13. "Tropical Plumes over the Middle East: Climatology and synoptic conditions"

    NASA Astrophysics Data System (ADS)

    Dayan, Uri; Tubi, Amit

    2015-04-01

    A 10-yr climatological study of Tropical Plumes (TPs) observed over the Middle East was undertaken. Several tools were used to identify and analyze these mid-tropospheric elongated cloudbands: satellite images, reanalysis and radiosonde data, backward trajectories, and cluster analysis. In order to conduct an in-depth examination of the synoptic conditions controlling this tropical-extratropical phenomenon, a dual methodology was adopted. In the first analysis, the identified 45 plumes were classified to precipitative and non-precipitative. In the second analysis, backward trajectories of the plumes were clustered in order to detect their moisture origins and pathways. In addition to the well documented south-western plumes originating in West Africa, a more southern pathway was identified, in which moisture was transported from Central to East African sources. The 'south-western' plumes are associated with a southwards penetration of mid-latitude troughs, associated with an intensified thermal wind and a longer jet streak, extending as far as Northwestern Africa. In the 'southern' category the Sub-Tropical Jet is associated with an anticyclonic flow over the south of the Arabian Peninsula, serving as an essential vehicle advecting moisture from tropical origins. This moisture pathway is considerably shorter than the south-western one. Several conditions favor precipitation induced by TPs over the domain: a northward migration of the jet streak resulting in a weakening of the wind speed over the target area, a deeper trough at the 500 hPa level and a shorter moisture corridor.

  14. Synoptic conditions related to soil moisture-atmosphere interactions and unorganized convection in Oklahoma

    NASA Astrophysics Data System (ADS)

    Ford, Trent W.; Quiring, Steven M.; Frauenfeld, Oliver W.; Rapp, Anita D.

    2015-11-01

    Atmospheric modification by anomalously dry or wet soils can both enhance and suppress convective activity. However, the local-scale and mesoscale feedback governing soil moisture-precipitation coupling are embedded within the larger synoptic-scale environment. Despite their importance, synoptic-scale atmospheric conditions are rarely considered in studies examining soil moisture-atmosphere interactions. We combine self-organizing maps of 500 hPa geopotential height, spatial synoptic classification, and Hybrid Single-Particle Lagrangian Integrated Trajectory model air mass trajectories to determine if the synoptic-scale environment affects the ability of the land surface to force unorganized convection in Oklahoma. We identify several synoptic patterns that significantly impact the frequency of unorganized convection. Synoptic patterns characterized by midlevel troughs over the Southern Great Plains are less frequently associated with unorganized convective events. These patterns exhibit cool air advection in the midlevel and lower level of the atmosphere and are linked to suppression of convective activity. The synoptic patterns characterized by 500 hPa ridging over the study region are more frequently associated with unorganized convective events. These patterns likely result in increased net radiation, vapor pressure deficit, and more homogenously dry soils. Unorganized convective events that occur during these synoptic conditions initiate preferentially over dry soils. We present evidence that the synoptic-scale environment can influence whether and how the land surface has an impact on convection.

  15. Synoptic conditions producing cirrus during the FIRE cirrus IFO

    NASA Technical Reports Server (NTRS)

    Starr, David OC.; Wylie, Donald P.

    1990-01-01

    Although direct observations of cirrus clouds by the FIRE research aircraft were usually confined to the area of Intensive Field Observation (IFO) surface network, these cirrus were generally part of a more extensive zone of upper level cloudiness. It is these large scale patterns of cirriform cloud and their relationship to the corresponding synoptic environment which are the prime focus. Three conceptual models are presented and each of the individual cases are classified into one of these categories. Although the cases manifest significant differences in intensity and small scale structure, it is believed that they are best viewed in this unified context. The descriptions given are mostly qualitative, however, quantitative descriptions of the synoptic control and its relationship to cloud structure for all the IFO cases are summarized. The synoptic situations in which extensive cirriform clouds were observed are classified into three basic types: warm front cases, cold front cases, and closed low aloft cases. A simplified summary of each type of situation is presented.

  16. Greece

    Atmospheric Science Data Center

    2013-04-17

    ... MD. The MISR data were obtained from the NASA Langley Research Center Atmospheric Science Data Center in Hampton, VA. Image ... Maria Kanakidou and Nikos Mihalopoulos, Department of Chemistry, University of Crete, Heraklion, Greece. Other formats ...

  17. Greece.

    PubMed

    1985-04-01

    A brief description of the population characteristics, geographical features, history, current political situation, economy, energy supply, foreign relations of Greece is presented. Greece's population of 9.95 million is 98% Greek, and the official language is Greek. 97% of the population is Greek Orthodox, and 2% is Muslim. Schooling is compulsory for 9 years, and the literacy rate is 89% for women and 96% for men. The infant mortality rate is 13.8, and life expectancy is 72 years for males and 75 years for female. Greece is situated on the southern tip of the Balkan Peninsula and consists of the mainland, the Peleponnesos, and numerous islands including Crete. Most of the land mass is mountainous, large areas are dry, and only 28% of the land is arable. From the earliest time until recently, emigration from Greece to other countries was a common pattern. Since the 1960s, internal migration to urban areas was the dominant migration trend. Currently, 30% of the population lives in Athens. Despite the growing industrialization and urbanization of the population, the Greeks retain many traditional family and social values. Greece was part of the cradle of civilization, and its history is characterized by the rise of the Minoan culture on Crete, the rise and fall of the Myceneans on the Peleponnesos, the development of the city states of Athens and Sparta, the destruction of Athens during the Peloponnesian War, domination by the Macedonians, the creation of the Hellenistic cilivization, conquest by the Roman Empire, the establishment of the Byzantine Empire, and in 1459 conquest by the Ottoman Empire. In the 1820's Greece fought for and finally won its independence, In World War I Greece fought on the side of the Allies. In World War II, the Greeks successfully resisted an invasion from Italy. In 1941, the country was taken over by the Germans, but the Greek resistance movement continued to fight the Germans until liberation. Between 1944-49, there were 2 unsuccessful

  18. Greece

    Atmospheric Science Data Center

    2013-04-17

    ... from north to south and between Greece and western Turkey, are uniquely situated at the intersection of Europe, Asia and Africa. ... Cyclades, Dodecanese and Crete, as well as part of mainland Turkey. Many sites important to ancient and modern history can be found here. ...

  19. Synoptic Scale Meteorological Conditions of Dust Events over the Southwestern Border Region of the US

    NASA Astrophysics Data System (ADS)

    Armenta, R. B.; DuBois, D. W.; Bleiweiss, M. P.; Novlan, D. J.

    2015-12-01

    Dust storms affect the environment, health and economics of a region. For these reasons it is important to understand the main causes and sources of windblown dust in the southwestern border region of the US. To help us understand the causes of the dust storms in our region, we are attempting to determine the synoptic scale meteorological conditions present at the time of approximately 60 dust storm events (from about 600 dust events over a 15 year period). From that, we will develop a "synoptic scale climatology" for dust events in the border region. To develop this climatology, we are using the NARR 500mb geopotential height patterns at 18GMT (approximate time of initial dust emission) to investigate whether our "observational" experience agrees with our hypothesis that a 500mb geopotential height low pressure pattern exists in the vicinity of the NM/CO border (latitudinal extent) and, depending on the timing of the event and other influences, somewhere from UT to TX (longitudinal extent). In our analysis we are comparing individual 500mb geopotential height patterns to a mean 500mb geopotential height pattern. Our preliminary results indicate that our observations are valid. Our goal is to develop a tool for forecasting these types of events.

  20. Synoptic conditions favouring the occurrence of strong aerosol episodes over the broader Mediterranean basin

    NASA Astrophysics Data System (ADS)

    Gkikas, A.; Houssos, E. E.; Bartzokas, A.; Hatzianastassiou, N.

    2010-09-01

    The present work aims at determining the synoptic conditions that favour the occurrence of strong aerosol episodes over the broader Mediterranean basin. In a first step, an objective and dynamic algorithm was set up to identify the strong aerosol episodes, based on daily aerosol optical depth values at 550nm (AOD550nm) from MODIS-Terra satellite database over the period 2000-2007. According to the algorithm, strong aerosol episodes occurred in each geographical cell (1o x 1o spatial resolution) of the study area whenever AODmean+2STDV≤AOD550nmsynoptic conditions, prevailing during the days of strong aerosol episodes, the fields of geopotential height at 500mb and mean sea level pressure (SLP) taken from the NCEP/NCAR reanalysis project, were used. At first, Factor analysis (S-mode) has been applied, in order to decrease the dimensionality of the raw atmospheric field data (500hPa and SLP). In a further step, Cluster Analysis was also applied to identify/classify the prevailing atmospheric circulation types during the aerosol episodes, into 7 representative clusters. The intra-annual variation of the frequency of occurrence, for each cluster, reveals that strong aerosol episodes mostly occur during spring and summer (89%). This can be attributed either to the stable atmospheric conditions and to the small precipitation amounts (especially in summer) that lead to the accumulation of aerosol particles in the atmosphere or to the prevailing synoptic conditions

  1. Analysis of southeast Australian zooplankton observations of 1938-42 using synoptic oceanographic conditions

    NASA Astrophysics Data System (ADS)

    Baird, Mark E.; Everett, Jason D.; Suthers, Iain M.

    2011-03-01

    The research vessel Warreen obtained 1742 planktonic samples along the continental shelf and slope of southeast Australia from 1938-42, representing the earliest spatially and temporally resolved zooplankton data from Australian marine waters. In this paper, Warreen observations along the southeast Australian seaboard from 28°S to 38°S are interpreted based on synoptic meteorological and oceanographic conditions and ocean climatologies. Meteorological conditions are based on the NOAA-CIRES 20th Century Reanalysis Project; oceanographic conditions use Warreen hydrological observations, and the ocean climatology is the CSIRO Atlas of Regional Seas. The Warreen observations were undertaken in waters on average 0.45 °C cooler than the climatological average, and included the longest duration El Niño of the 20th century. In northern New South Wales (NSW), week time-scale events dominate zooplankton response. In August 1940 an unusual winter upwelling event occurred in northern NSW driven by a stronger than average East Australian Current (EAC) and anomalous northerly winds that resulted in high salp and larvacean abundance. In January 1941 a strong upwelling event between 28° and 33°S resulted in a filament of upwelled water being advected south and alongshore, which was low in zooplankton biovolume. In southern NSW a seasonal cycle in physical and planktonic characteristics is observed. In January 1941 the poleward extension of the EAC was strong, advecting more tropical tunicate species southward. Zooplankton abundance and distribution on the continental shelf and slope are more dependent on weekly to monthly timescales on local oceanographic and meteorological conditions than continental-scale interannual trends. The interpretation of historical zooplankton observations of the waters off southeast Australia for the purpose of quantifying anthropogenic impacts will be improved with the use of regional hindcasts of synoptic ocean and atmospheric weather that can

  2. Statistical approach for assessing the influence of synoptic and meteorological conditions on ozone concentrations over Europe

    NASA Astrophysics Data System (ADS)

    Otero, Noelia; Butler, Tim; Sillmann, Jana

    2015-04-01

    Air pollution has become a serious problem in many industrialized and densely-populated urban areas due to its negative effects on human health, damages agricultural crops and ecosystems. The concentration of air pollutants is the result of several factors, including emission sources, lifetime and spatial distribution of the pollutants, atmospheric properties and interactions, wind speed and direction, and topographic features. Episodes of air pollution are often associated with stationary or slowly migrating anticyclonic (high-pressure) systems that reduce advection, diffusion, and deposition of atmospheric pollutants. Certain weather conditions facilitate the concentration of pollutants, such as the incidence of light winds that contributes to the increasing of stagnation episodes affecting air quality. Therefore, the atmospheric circulation plays an important role in air quality conditions that are affected by both, synoptic and local scale processes. This study assesses the influence of the large-scale circulation along with meteorological conditions on tropospheric ozone in Europe. The frequency of weather types (WTs) is examined under a novel approach, which is based on an automated version of the Lamb Weather Types catalog (Jenkinson and Collison, 1977). Here, we present an implementation of such classification point-by-point over the European domain. Moreover, the analysis uses a new grid-averaged climatology (1°x1°) of daily surface ozone concentrations from observations of individual sites that matches the resolution of global models (Schnell,et al., 2014). Daily frequency of WTs and meteorological conditions are combined in a multiple regression approach for investigating the influence on ozone concentrations. Different subsets of predictors are examined within multiple linear regression models (MLRs) for each grid cell in order to identify the best regression model. Several statistical metrics are applied for estimating the robustness of the

  3. Identifying the most hazardous synoptic meteorological conditions for Winter UK PM10 exceedences

    NASA Astrophysics Data System (ADS)

    Webber, Chris; Dacre, Helen; Collins, Bill; Masato, Giacomo

    2016-04-01

    Summary We investigate the relationship between synoptic scale meteorological variability and local scale pollution concentrations within the UK. Synoptic conditions representative of atmospheric blocking highlighted significant increases in UK PM10 concentration ([PM10]), with the probability of exceeding harmful [PM10] limits also increased. Once relationships had been diagnosed, The Met Office Unified Model (UM) was used to replicate these relationships, using idealised source regions of PM10. This helped to determine the PM10 source regions most influential throughout UK PM10 exceedance events and to test whether the model was capable of capturing the relationships between UK PM10 and atmospheric blocking. Finally, a time slice simulation for 2050-2060 helped to answer the question whether PM10 exceedance events are more likely to occur within a changing climate. Introduction Atmospheric blocking events are well understood to lead to conditions, conducive to pollution events within the UK. Literature shows that synoptic conditions with the ability to deflect the Northwest Atlantic storm track from the UK, often lead to the highest UK pollution concentrations. Rossby wave breaking (RWB) has been identified as a mechanism, which results in atmospheric blocking and its relationship with UK [PM10] is explored using metrics designed in Masato, et al., 2013. Climate simulations facilitated by the Met Office UM, enable these relationships between RWB and PM10 to be found within the model. Subsequently the frequency of events that lead to hazardous PM10 concentrations ([PM10]) in a future climate, can be determined, within a climate simulation. An understanding of the impact, meteorology has on UK [PM10] within a changing climate, will help inform policy makers, regarding the importance of limiting PM10 emissions, ensuring safe air quality in the future. Methodology and Results Three Blocking metrics were used to subset RWB into four categories. These RWB categories

  4. Numerical simulation of tornadoes' meteorological conditions over Greece: A case study of tornadic activity over NW Peloponnese on March 25, 2009

    NASA Astrophysics Data System (ADS)

    Matsangouras, Ioannis T.; Nastos, Panagiotis T.; Pytharoulis, Ioannis

    2014-05-01

    Recent research revealed that NW Peloponnese, Greece is an area that favours pre-frontal tornadic incidence. This study presents the results of the synoptic analysis of the meteorological conditions during a tornado event over NW Peloponnese on March 25, 2009. Further, the role of topography in tornado genesis is examined. The tornado was formed approximately at 10:30 UTC, south-west of Vardas village, crossed the Nea Manolada and faded away at Lappas village, causing several damage. The length of its track was approximately 9-10 km and this tornado was characterized as F2 (Fujita scale) or T4-T5 in TORRO intensity scale. Synoptic analysis was based on ECMWF datasets, as well as on daily composite mean and anomaly of the geopotential heights at the middle and lower troposphere from NCEP/NCAR reanalysis. In addition, numerous datasets derived from weather observations and remote sensing were used in order to interpret better the examined extreme event. Finally, a numerical simulation was performed using the non-hydrostatic Weather Research and Forecasting model (WRF), initialized with ECMWF gridded analyses, with telescoping nested grids that allow the representation of atmospheric circulations ranging from the synoptic scale down to the meso-scale. In the numerical simulations the topography of the inner grid was modified by: a) 0% (actual topography) and b) -100% (without topography).

  5. Synoptic-scale atmospheric conditions associated with flash flooding in watersheds of the Catskill Mountains, New York, USA

    NASA Astrophysics Data System (ADS)

    Teale, N. G.; Quiring, S. M.

    2015-12-01

    Understanding flash flooding is important in unfiltered watersheds, such as portions of the New York City water supply system (NYCWSS), as water quality is degraded by turbidity associated with flooding. To further understand flash flooding in watersheds of the NYCWSS, synoptic-scale atmospheric conditions most frequently associated with flash flooding between 1987 and 2013 were examined. Flash floods were identified during this time period using USGS 15-minute discharge data at the Esopus Creek near Allaben, NY and Neversink River at Claryville, NY gauges. Overall, 25 flash floods were detected, occurring over 17 separate flash flood days. These flash flood days were compared to the days on which flash flood warnings encompassing the study area was issued by the National Weather Service. The success rate for which the flash flood warnings for Ulster County coincided with flash flood in the study watershed was 0.09, demonstrating the highly localized nature of flash flooding in the Catskill Mountain region. The synoptic-scale atmospheric patterns influencing the study area were characterized by a principal component analysis and k-means clustering of NCEP/NCAR 500 mb geopotential height reanalysis data. This procedure was executed in Spatial Synoptic Typer Tools 4.0. While 17 unique synoptic patterns were identified, only 3 types were strongly associated with flash flooding events. A strong southwesterly flow suggesting advection of moisture from the Atlantic Ocean and Gulf of Mexico is shown in composites of these 3 types. This multiscalar study thereby links flash flooding in the NYCWSS with synoptic-scale atmospheric circulation.Understanding flash flooding is important in unfiltered watersheds, such as portions of the New York City water supply system (NYCWSS), as water quality is degraded by turbidity associated with flooding. To further understand flash flooding in watersheds of the NYCWSS, synoptic-scale atmospheric conditions most frequently associated with

  6. Atmospheric synoptic conditions of snow precipitation in East Antarctica using ice core and reanalysis data

    NASA Astrophysics Data System (ADS)

    Scarchilli, Claudio; Ciardini, Virginia; Bonazza, Mattia; Frezzotti, Massimo; Stenni, Barbara

    2014-05-01

    In the framework of the International Partnerships in Ice Core Sciences (IPCS) initiatives the GV7 site (70°41' S - 158°51' E) in East Antarctica was chosen as the new drilling site for the Italian contribution to the understanding of the climatic variability in the last 2000 years (IPICS 2k Array). Water stable isotopes and snow accumulation (SMB) values from a shallow firn core, obtained at GV7 during the 2001-2002 International Trans-Antarctic Scientific Expedition (ITASE) traverse, are analyzed and compared with different meteorological model output in order to characterize the atmospheric synoptic conditions driving precipitation events at the site. On annual basis, ECMWF +24h forecasted snowfalls (SF) seem to well reproduce GV7 SMB values trend for the period from 1980 to 2005. Calculated air mass back-trajectories show that Eastern Indian - Western Pacific oceans represent the main moisture path toward the site during autumn - winter season. Analysis of the ECMWF 500 hPa Geopotential height field (GP500) anomalies shows that atmospheric blocking events developing between 130° E and 150° W at high latitudes drive the GV7 SMB by blocking zonal flow and conveying warm and moist deep air masses from ocean into the continental interior. On inter-annual basis, The SF variability over GV7 region follows the temporal oscillation of the third CEOF mode (CEOF3 10% of the total explained variance) of a combined complex empirical orthogonal function (CEOF) performed over GP500 and SF field. The CEOF3 highlights an oscillating feature, with wavenumber 2, in GP500 field over the Western Pacific-Eastern Indian Oceans and propagating westward. The pattern is deeply correlated with the Indian Dipole Oscillation and ENSO and their associated quasi-stationary Rossby waves propagating from the lower toward the higher latitudes.

  7. Statistical modeling of urban air temperature distributions under different synoptic conditions

    NASA Astrophysics Data System (ADS)

    Beck, Christoph; Breitner, Susanne; Cyrys, Josef; Hald, Cornelius; Hartz, Uwe; Jacobeit, Jucundus; Richter, Katja; Schneider, Alexandra; Wolf, Kathrin

    2015-04-01

    Within urban areas air temperature may vary distinctly between different locations. These intra-urban air temperature variations partly reach magnitudes that are relevant with respect to human thermal comfort. Therefore and furthermore taking into account potential interrelations with other health related environmental factors (e.g. air quality) it is important to estimate spatial patterns of intra-urban air temperature distributions that may be incorporated into urban planning processes. In this contribution we present an approach to estimate spatial temperature distributions in the urban area of Augsburg (Germany) by means of statistical modeling. At 36 locations in the urban area of Augsburg air temperatures are measured with high temporal resolution (4 min.) since December 2012. These 36 locations represent different typical urban land use characteristics in terms of varying percentage coverages of different land cover categories (e.g. impervious, built-up, vegetated). Percentage coverages of these land cover categories have been extracted from different sources (Open Street Map, European Urban Atlas, Urban Morphological Zones) for regular grids of varying size (50, 100, 200 meter horizonal resolution) for the urban area of Augsburg. It is well known from numerous studies that land use characteristics have a distinct influence on air temperature and as well other climatic variables at a certain location. Therefore air temperatures at the 36 locations are modeled utilizing land use characteristics (percentage coverages of land cover categories) as predictor variables in Stepwise Multiple Regression models and in Random Forest based model approaches. After model evaluation via cross-validation appropriate statistical models are applied to gridded land use data to derive spatial urban air temperature distributions. Varying models are tested and applied for different seasons and times of the day and also for different synoptic conditions (e.g. clear and calm

  8. Extreme summer temperatures in Iberia: health impacts and associated synoptic conditions

    NASA Astrophysics Data System (ADS)

    García-Herrera, R.; Díaz, J.; Trigo, R. M.; Hernández, E.

    2005-02-01

    This paper examines the effect of extreme summer temperatures on daily mortality in two large cities of Iberia: Lisbon (Portugal) and Madrid (Spain). Daily mortality and meteorological variables are analysed using the same methodology based on Box-Jenkins models. Results reveal that in both cases there is a triggering effect on mortality when maximum daily temperature exceeds a given threshold (34°C in Lisbon and 36°C in Madrid). The impact of most intense heat events is very similar for both cities, with significant mortality values occurring up to 3 days after the temperature threshold has been surpassed. This impact is measured as the percentual increase of mortality associated to a 1°C increase above the threshold temperature. In this respect, Lisbon shows a higher impact, 31%, as compared with Madrid at 21%. The difference can be attributed to demographic and socio-economic factors. Furthermore, the longer life span of Iberian women is critical to explain why, in both cities, females are more susceptible than males to heat effects, with an almost double mortality impact value. The analysis of Sea Level Pressure (SLP), 500hPa geopotential height and temperature fields reveals that, despite being relatively close to each other, Lisbon and Madrid have relatively different synoptic circulation anomalies associated with their respective extreme summer temperature days. The SLP field reveals higher anomalies for Lisbon, but extending over a smaller area. Extreme values in Madrid seem to require a more western location of the Azores High, embracing a greater area over Europe, even if it is not as deep as for Lisbon. The origin of the hot and dry air masses that usually lead to extreme heat days in both cities is located in Northern Africa. However, while Madrid maxima require wind blowing directly from the south, transporting heat from Southern Spain and Northern Africa, Lisbon maxima occur under more easterly conditions, when Northern African air flows over the

  9. Rawinsonde sounding data and synoptic conditions for the CCOPE-VAS experiment, July 1981

    NASA Technical Reports Server (NTRS)

    Henry, W. K.

    1982-01-01

    During the cooperative convective precipitation experiment, eight times were selected as VISSR atmospheric sounder (VAS) observation periods. A synoptic analysis of the surface and the 850, 700, 500, 300, and 200 maps for those eight periods. The satellite and radar data for those periods are included with the analyses. There were five rawinsonde stations in eastern Montana which made extra soundings for the VAS periods.

  10. Synoptical situations and meteorological conditions associated to floods in the mouth of rivers in the European part of Russia

    NASA Astrophysics Data System (ADS)

    Matveeva, Tatiana; Gushchina, Daria

    2013-04-01

    The synoptical situations associated to the various type of floods in the mouth of rivers in European part of Russia are described. The storm surges, water flows and ice-jams are considered for Baltic, Barents sea, White sea, Azov sea, Black sea and Caspian sea regions. It is shown that the specific types of flood may be associated to various synoptical situations. Therefore it is unlikely to introduce the classification of synoptical regimes resulting in specific type of floods. However for each zone under consideration and for each specific flood type it is possible to determine the potential predictors of inundation: i.e. meteorological parameters which are characteristics of all cases of specific flood. There are: • for storm surges - long term wind forcing resulting in seiches in the sea, strong wind speed (the threshold varies in dependence on region), the wind direction orthogonal to the flow of river and strong baric gradient; • for water flows - the abundant precipitation, usually associate with the intensive frontal zone, the sudden change of air temperature resulting in snow melting in spring time; • for ice-jams - the strong temperature gradient extended in north-south direction resulting in negative temperature in the river mouth and positive temperature in the other basin. The probability of occurrence of predictors mentioned above was estimated for modern climate and global warming conditions using the outputs of ECHAM5/MPI-OM model. It is shown that the occurrence of intensive frontal zone and rainfall in the South of Russia will increase (decrease) in summer (winter) under warmer climate conditions which may contribute to the increase of water flows in this region. Maximum of floods occurs during the warm period, we can conclude that global warming increases the risk of floods in Black Sea coast.

  11. Synoptic conditions favouring the occurrence of dust transport from Africa toward Sardinia Island.

    NASA Astrophysics Data System (ADS)

    Canu, Annalisa; Pellizzaro, Grazia; Pintus, Gabriella; Duce, Pierpaolo

    2016-04-01

    Dust events that reach Italy have usually origin in the Sahara and Sahel regions (north-western part of Africa), which represent the dust sources nearest to Italy. In those regions the dust-lifting activity occurs in a remarkable way. Every dust event is different from the others; in fact dust transport and dust concentration in the air can vary remarkably depending on the synoptic situation. In Sardinia, dust events are more frequent in the May-November period, but they can also take place in the December-April period. The main aim of this work was to describe dust outbreaks in Sardinia and to identify the main meteorological scenarios that originate the transport of dust towards the central and western Mediterranean Basin. The evaluation of the geographical dispersion of Saharan dust was performed by using MODIS satellite data and Meteosat imagery combined with SKIRON forecasting model. The origin and the trajectory of the dust carried by winds towards Italy were inferred by the NOAA HYSPLIT model (Hybrid Single Particle Lagrangian Integrated Trajectory Model). In addition, PM10 (particulate matter with a diameter of less than 10 μm) and meteorological data registered by the ARPAS (Regional Environmental Protection Agency of Sardinia) monitoring stations were used to highlight the arrival of African air masses in Sardinia. The study was carried out during the 2014. A total of five events occurred during the year (two in spring and three in autumn) were analyzed. The origin of air masses loaded with dust from North Africa was confirmed by satellite imagery and 3-days air mass backward trajectories calculated by the NOAA HYSPLIT model. The analysis of the PM10 daily pattern registered at northern and southern Sardinia sites showed a rising of values during the dust event. The arrival of air masses from Africa caused the daily mean air temperature to rise whereas relative humidity values decreased. Finally, the results showed that all the event analyzed were

  12. Association of joint occurrence of warm and dry conditions over Greece with anticyclonic activity during summer

    NASA Astrophysics Data System (ADS)

    Hatzaki, Maria; Nastos, Panagiotis; Polychroni, Iliana; Flocas, Helena A.; Kouroutzoglou, John; Dalezios, Nicolas R.

    2016-04-01

    Anticyclones are often associated with extreme phenomena, like prolonged droughts or heatwaves and, thus, they can significantly impact fauna and flora, water resources and public health. In this study, the association of the summer anticyclonic activity with the joint occurrence of extreme warm and dry conditions over Greece is explored. The warm and dry extreme conditions are defined by utilizing the Warm/Dry (WD) index for representative meteorological stations from sub-regions of Greece with different climatic features. The WD index is the number of days over a period (here summer) having at the same time mean air temperature > 75th percentile of daily mean temperature and precipitation < 25th percentile of daily precipitation amounts. The anticyclonic activity is determined by the density of the anticyclonic systems over the greater Mediterranean region, which, during summer, is maximized over the Balkans and the northern African coast. The anticyclonic system density has resulted from the comprehensive climatology of Mediterranean anticyclones that was assembled with the aid of the finding and tracking scheme of the University of Melbourne (MS scheme), using the ERA-Interim mean sea-level pressure fields for 1979-2012. The examination of inter-annual and spatial variations of the WD index in association with shifts of the anticyclonic maxima shows that the different sub-regions of Greece are not affected evenly, stressing the role of the complex topography of the region and the variations in the subtropical jet position.

  13. Assessment of bioclimatic conditions in Crete Island, Greece

    NASA Astrophysics Data System (ADS)

    Bleta, A.; Nastos, P. T.; Matzarakis, A.

    2012-04-01

    The objective of this study is to assess and analyze the human bioclimatic conditions of Crete Island, using the Physiologically Equivalent Temperature (PET), which is one of the most popular human thermal indices derived from the human energy balance. Bioclimatic studies provide a framework linking biophysical climate sensitivity to social/economic factors that mitigate or amplify the consequences of environmental changes. PET is defined as the physiological equivalent temperature at any given place (outdoors or indoors). It is equivalent to the air temperature at which, in a typical indoor setting, the heat balance of the human body (work metabolism 80 W of light activity, added to basic metabolism; heat resistance of clothing 0.9 clo) is maintained with core and skin temperatures equal to those of the under assessment conditions. It has been realized that, to estimate the thermal effect of the environment to the human body, the total of effects of all of the thermal components, not only as individual parameters, should be taken into account. The climatic data (air temperature, relative humidity, cloudiness, wind speed) for Crete Island, were obtained by archives of fifteen meteorological stations of the Hellenic National Meteorological Service (HNMS). These data of period 1955-2010 were used for the calculation of PET in order to interpret the grade of the thermo-physiological stress. Crete Island, as it is located in the Southeastern Mediterranean basin, is of great touristic interest due to its splendid landscapes, archaeological sites and coastal areas combined with its excellent climatic conditions. However, Crete Island is frequently affected by Saharan outbreaks which are associated with miscellaneous phenomena, such as Föhn winds - hot and dry winds - causing extreme bioclimatic conditions (strong heat stress). The exploitation of the results of this analysis, such as bioclimatic diagrams, temporal and spatial distributions of PET as well as trends and

  14. Impacts of mountains on black carbon aerosol under different synoptic meteorology conditions in the Guanzhong region, China

    NASA Astrophysics Data System (ADS)

    Zhao, Shuyu; Tie, Xuexi; Cao, Junji; Zhang, Qiang

    2015-10-01

    The Xi'an City and the surrounding area (the Guan-Zhong-GZ region) in western China have been suffering severe air pollutions during wintertime in recent years. In-situ black carbon (BC) measurement combined with a regional dynamical and chemical model (WRF-Chem model) is used to investigate the formation of a haze episode occurred from Jan. 3rd to Jan. 13th 2013. The results show that the measured BC concentrations exhibit a large day-to-day variability. The impacts of synoptic weather systems, local meteorological parameters and mountain effect on the BC variability are studied. Because the GZ region is surrounded by two major mountains, the Loess Plateau in the north and the Qinling Mountains in the south, especially the peak of the Qinling Mountains higher than 3000 m, we particularly analyze the effects of the Qinling Mountains on the BC pollution. The analysis shows that the BC pollution in Xi'an City and the GZ region is strongly affected by the synoptic weather systems, local meteorological winds and the Qinling Mountains. Under a typical northeast wind condition, winds are blocked by the Qinling Mountains, and BC particles are trapped at the foothill of the mountains, resulting in high BC concentrations in the city of Xi'an. Under a typical east wind condition, BC particles are transported along a river valley and the foothill of the Qinling Mountains. In this case, the mountain-river valley plays a role to accelerate the east wind, resulting in a reduction of the BC pollution. Under a typical calm wind condition, the BC particles are less diffused from their source region, and there is a mountain breeze from the Qinling Mountains to the city of Xi'an, and BC particles accumulate in the city, especially in the north side of the city. This study illustrates that while locating between complicated terrain conditions, such as the GZ region, the mountains play very important roles for the formation of hazes in the region.

  15. Synoptic aspects of wet and dry conditions in central Australia: Observations and GCM simulations for 1 {times} CO{sub 2} and 2 {times} CO{sub 2} conditions

    SciTech Connect

    Suppiah, R.

    1994-11-01

    Synoptic climatological patterns that produce anomalous wet conditions in central Australia during the period form September to April have been studied. The analysis was done by using observed daily rainfall data at a number of stations, wind and mean sea level pressure from the European Centre for Medium Range Weather Forecasts (ECMWF), Tropical Ocean and Global Atmosphere (TOGA) data form 1985 to 1991, and the CSIRO 9-level (CSIRO9) global climate model (GCM) simulated data for 1 {times} CO{sub 2} and 2 {times} CO{sub 2} experiments. For rainfall values above 99.5 percentile in observed and simulated data, wet days have been selected to study the synoptic-scale weather systems that produce anomalous wet events in central Australia. As the vast majority of days in central Australia are dry, the same number of days with no rainfall for both observed and simulated conditions have been selected randomly. A comparison between CSIRO9 simulated synoptic patterns and observed synoptic patterns reveals that the model fairly well captures the synoptic climatological characteristics which produce anomalous wet and contrasting dry weather conditions during the period from September to April. Under enhanced greenhouse experiments, the main features of the synoptic patterns are intensified both for wet and dry conditions, which result in an increase in extreme-weather conditions, an increase in rainfall intensity, a spatial expansion of the heavy rainfall region during wet days, and an expansion of the dry area during dry days. During anomalous wet conditions, the low pressure area is intensified, monsoonal winds and southeasterlies are strengthened and strong wind shear over tropical Australia is simulated. During this condition, the monsoon shear line moves poleward particularly over the Northern Territory. In contrast, during dry conditions, the anticyclonic circulation over the continent is strengthened.

  16. CMAQ predictions of tropospheric ozone in the U.S. southwest: influence of lateral boundary and synoptic conditions.

    PubMed

    Shi, Chune; Fernando, H J S; Hyde, Peter

    2012-02-01

    Phoenix, Arizona, has been an ozone nonattainment area for the past several years and it remains so. Mitigation strategies call for improved modeling methodologies as well as understanding of ozone formation and destruction mechanisms during seasons of high ozone events. To this end, the efficacy of lateral boundary conditions (LBCs) based on satellite measurements (adjusted-LBCs) was investigated, vis-à-vis the default-LBCs, for improving the predictions of Models-3/CMAQ photochemical air quality modeling system. The model evaluations were conducted using hourly ground-level ozone and NO(2) concentrations as well as tropospheric NO(2) columns and ozone concentrations in the middle to upper troposphere, with the 'design' periods being June and July of 2006. Both included high ozone episodes, but the June (pre-monsoon) period was characterized by local thermal circulation whereas the July (monsoon) period by synoptic influence. Overall, improved simulations were noted for adjusted-LBC runs for ozone concentrations both at the ground-level and in the middle to upper troposphere, based on EPA-recommended model performance metrics. The probability of detection (POD) of ozone exceedances (>75ppb, 8-h averages) for the entire domain increased from 20.8% for the default-LBC run to 33.7% for the adjusted-LBC run. A process analysis of modeling results revealed that ozone within PBL during bulk of the pre-monsoon season is contributed by local photochemistry and vertical advection, while the contributions of horizontal and vertical advections are comparable in the monsoon season. The process analysis with adjusted-LBC runs confirms the contributions of vertical advection to episodic high ozone days, and hence elucidates the importance of improving predictability of upper levels with improved LBCs. PMID:22227303

  17. Spray drift reduction under Southern European conditions: a pilot study in the Ecopest Project in Greece.

    PubMed

    Kasiotis, Konstantinos M; Glass, C Richard; Tsakirakis, Angelos N; Machera, Kyriaki

    2014-05-01

    The objective of this work was to generate spray drift data from pesticide application in the field comparing spray drift from traditional equipment with emerging, anti-drift technologies. The applications were carried out in the Kopais area in central Greece. Currently few data exist as regards to pesticide spray drift in Southern European conditions. This work details the data for ground and airborne deposition of spray drift using the methodology developed in the UK by the Food and Environment Research Agency (FERA). Three trials were performed in two days using sunset yellow dye which deposited on dosimeters placed at specific distances from the edge of the sprayer boom. The application was carried out with a tractor mounted boom sprayer, which was of local manufacture, as were the nozzles of Trial I, being flat fan brass nozzles. For Trials II and III anti-drift nozzles were used. The boom sprayers were used with the settings as employed by the farmers for the routine pesticide applications. The results of this work indicate that drift was significantly reduced when anti-drift nozzles were utilized. PMID:24561292

  18. The impact of the uncertainty in the initial soil moisture condition of irrigated areas on the spatiotemporal characteristics of convective activity in Central Greece

    NASA Astrophysics Data System (ADS)

    Kotsopoulos, Stylianos; Ioannis, Tegoulias; Ioannis, Pytharoulis; Stergios, Kartsios; Dimitrios, Bampzelis; Theodore, Karacostas

    2015-04-01

    The region of Thessaly is the second largest plain in Greece and has a vital role in the financial life of the country, because of its significant agricultural production. The intensive and extensive cultivation of irrigated crops, in combination with the population increase and the alteration of precipitation patterns due to climate change, often leading the region to experience severe drought conditions, especially during the warm period of the year. The aim of the DAPHNE project is to tackle the problem of drought in this area by means of Weather Modification.In the framework of the project DAPHNE, the numerical weather prediction model WRF-ARW 3.5.1 is used to provide operational forecasts and hindcasts for the region of Thessaly. The goal of this study is to investigate the impact of the uncertainty in the initial soil moisture condition of irrigated areas, on the spatiotemporal characteristics of convective activity in the region of interest. To this end, six cases under the six most frequent synoptic conditions, which are associated with convective activity in the region of interest, are utilized, considering six different soil moisture initialization scenarios. In the first scenario (Control Run), the model is initialized with the surface soil moisture of the ECMWF analysis data, that usually does not take into account the modification of soil moisture due to agricultural activity in the area of interest. In the other five scenarios (Experiment 1,2,3,4,5) the soil moisture in the upper soil layers of the study area are modified from -50% to 50% of field capacity (-50%FC, -25%FC, FC, 25%FC, 50%FC),for the irrigated cropland.Three model domains, covering Europe, the Mediterranean Sea and northern Africa (d01), the wider area of Greece (d02) and central Greece - Thessaly region (d03) are used at horizontal grid-spacings of 15km, 5km and 1km respectively. ECMWF operational analyses at 6-hourly intervals (0.25ox0.25o lat.-long.) are imported as initial and

  19. Present and Future Human Thermal Bioclimatic Conditions and Impacts on Respiratory Admissions in Crete Island, Greece

    NASA Astrophysics Data System (ADS)

    Bleta, Anastasia; Nastos, Panagiotis

    2015-04-01

    The objective of this study is to assess and quantify the association between present and future human thermal bioclimatic conditions and daily counts of respiratory problems in Heraklion city, Crete Island, Greece. The bioclimatic conditions were analyzed in terms of the Physiologically Equivalent Temperature (PET) and Universal Thermal Climate Index (UTCI), which are two of the most popular human thermal indices based on the human energy balance. The PET and UTCI analysis was performed by the application of the bioclimate model, "RayMan", which is well-suited to calculate radiation fluxes and human biometeorological indices. Future changes in meteorological parameters such as air temperature, relative humidity, wind speed and cloudiness (used as input variables in the estimation of PET and UTCI) were derived by the simulations of the regional atmospheric climate model KNMI under SRES A1B, for the near (2021-2050) and far (2071-2100) future with respect to the reference period 1961-1990. Generalized linear models (GLM) with Poisson distribution were applied to the time series of daily numbers of outpatients (total, males and females) with respiratory problems against present and future bioclimatic changes, after controlling for possible confounders and adjustment for season and trends. The interpretation of the results of this analysis suggests a significant association between cold weather and increased respiratory admissions. For the near future, the projected increase of 1.6oC in PET may result in reducing the incidence of respiratory problemsby almost 3% against 7.5% in the far future, when PET is projected to increase by 4oC.

  20. The growth of prognostic differences between GLAS model forecasts from SAT and NOSAT initial conditions. [for synoptic meteorology

    NASA Technical Reports Server (NTRS)

    Atlas, R.

    1982-01-01

    A study has been conducted to determine the cause of a major synoptic difference in the 72 h GLAS model forecasts from 0000 GMT 19 February 1976 that resulted from the inclusion of satellite data. The prognostic differences that resulted in diverging cyclone paths between the forecast that included satellite temperature soundings (SAT) and the forecast that excluded satellite sounding data (NOSAT) have been traced to initial state differences in the upper level wind and temperature patterns. These modifications enhanced the variation of thermal vorticity and thermal advection across the cyclone center and in the SAT case, gave a greater initial rate of movement of the upper-level vorticity maximum associated with the surface cyclone.

  1. Tornadoes and waterspouts in Greece

    NASA Astrophysics Data System (ADS)

    Sioutas, Michalis V.

    Tornadoes and waterspouts occur in various parts of Greece and may often reach the media as remarkable events, depending of their intensity and the level of damage. This paper is based on a research started from the beginning of 2000 for identifying and recording tornadoes and waterspouts in Greece and evaluating their intensity and other fundamental characteristics. Search of historical events for obtaining more comprehensive tornado climatology is in progress. In an almost 3-year period, January 2000-September 2002, tornadoes and waterspouts have been reported from various parts of Greece, including western Greece, the Ionian islands and western Peloponnese mainly during autumn and winter. Northern Greece is affected by tornadic activity mostly during summer and early autumn. The geographical distribution showed a preference for tornado occurrence mainly in coastal areas. Based on this almost 3-year data sample, a mean number of six tornadoes per year has resulted, corresponding to a density of 0.45 10 -4 km -2 year -1. Maximum intensity of tornadoes recorded was rated as T6 of the Tornado and Storm Research Organization (TORRO) scale (F3 of the Fujita scale). A basic synoptic typing scheme is presented, including four synoptic circulation patterns associated to tornado occurrence.

  2. Tornado activity in Greece within the 20th Century

    NASA Astrophysics Data System (ADS)

    Nastos, P. T.; Matsaggouras, J.

    2009-09-01

    Tornado activity is associated with extreme convective weather which can cause extended damages and even more in some cases the loss of life. The complex inland terrain of Greece along with the Ionion Sea at the west and the Aegean Sea at the east appear to be a favorable area for fury phenomena such as tornado, waterspouts and funnel clouds. In this study, the spatial and temporal variability of tornadoes activity in Greece for the period 1910-1999 are presented. The spatial distribution of tornadoes, waterspouts and funnel clouds reveals the vulnerability of specific geographical areas to tornado activity, such as the western Greece and the southern Aegean Sea. As far as the intra annual variability is concerned, the maximum of tornadoes activity dominates within the cold period of the year (October-March) while according to the daily distribution, tornadoes happen frequently during the warm hours of the day. Furthermore, especially for the cases after 1957, the prevailing synoptic conditions during the tornado activity, based on the analysis of the 500 hPa Geopotential Heights from the archives of the European Centre for Medium-Range Weather Forecasts (ECMWF), were examined, in order to identify the weather patterns associated with the tornado genesis and development. It is remarkable to mention that in Greece, within the 20th century, the tornado activity caused the loss of 4 lifes, the injury of 40 people and numerous damages on human constructions and cultivations.

  3. What are the most fire-dangerous atmospheric circulations in the Eastern-Mediterranean? Analysis of the synoptic wildfire climatology.

    PubMed

    Paschalidou, A K; Kassomenos, P A

    2016-01-01

    Wildfire management is closely linked to robust forecasts of changes in wildfire risk related to meteorological conditions. This link can be bridged either through fire weather indices or through statistical techniques that directly relate atmospheric patterns to wildfire activity. In the present work the COST-733 classification schemes are applied in order to link wildfires in Greece with synoptic circulation patterns. The analysis reveals that the majority of wildfire events can be explained by a small number of specific synoptic circulations, hence reflecting the synoptic climatology of wildfires. All 8 classification schemes used, prove that the most fire-dangerous conditions in Greece are characterized by a combination of high atmospheric pressure systems located N to NW of Greece, coupled with lower pressures located over the very Eastern part of the Mediterranean, an atmospheric pressure pattern closely linked to the local Etesian winds over the Aegean Sea. During these events, the atmospheric pressure has been reported to be anomalously high, while anomalously low 500hPa geopotential heights and negative total water column anomalies were also observed. Among the various classification schemes used, the 2 Principal Component Analysis-based classifications, namely the PCT and the PXE, as well as the Leader Algorithm classification LND proved to be the best options, in terms of being capable to isolate the vast amount of fire events in a small number of classes with increased frequency of occurrence. It is estimated that these 3 schemes, in combination with medium-range to seasonal climate forecasts, could be used by wildfire risk managers to provide increased wildfire prediction accuracy. PMID:26383855

  4. Effects of synoptic-scale circulation pattern and local land surface condition on fog at Kushiro, northern Japan

    NASA Astrophysics Data System (ADS)

    Sugimoto, S.; Sato, T.; Nakamura, K.

    2012-12-01

    Marine stratiform clouds are frequently observed over western North Pacific offshore of the northeast Japan during summer when warm southerly wind prevails over underlying cold ocean current. Such clouds often migrate over Kushiro located in the coastal area of eastern Hokkaido Island, north Japan and are recognized as sea fog. On the other hand, Kushiro is a middle-sized city with population of over 180,000 and a large wetland expands at the north of Kushiro city. The difference of land surface condition between the city and the wetland might cause heterogeneity of the sea fog distribution over land, via dissipation and regeneration process of fog. In this study, long-term visibility data for Kushiro are investigated to clarify the relationship between interannual variation of fog frequency (FF) and large-scale circulation patterns. Furthermore, frequency of fog/low-level cloud (LC) is identified using satellite images and sensitivity experiments changing land surface condition are conducted using meteorological regional model to understand an impact of land use on the local fog distribution and its physical processes. Monthly mean FF trends observed at Kushiro during 1931 to 2010 shows significant decline (-3.3 day per decade). Since late 1970s, the decline at Kushiro has been particularly remarkable in July and August in association with an increased number of years with very low FF. Analysis of radiosonde data has revealed the development of shallow moist layer under a strong inversion layer during fog occurrence because of abundant moisture supply from southerly wind. However, cold and dry northerly wind prevents the formation of inversion layer during fog-free days. Composite analysis of reanalysis data suggests that the low-level southerly wind toward northeast Japan is weaker in the low FF month of July than climatology owing to a southward shift of the North Pacific High (NPH) and stronger Okhotsk High. In August, eastward displacement or shrinking of the

  5. A combined linear optimisation methodology for water resources allocation in Alfeios River Basin (Greece) under uncertain and vague system conditions

    NASA Astrophysics Data System (ADS)

    Bekri, Eleni; Yannopoulos, Panayotis; Disse, Markus

    2013-04-01

    In the present study, a combined linear programming methodology, based on Li et al. (2010) and Bekri et al. (2012), is employed for optimizing water allocation under uncertain system conditions in the Alfeios River Basin, in Greece. The Alfeios River is a water resources system of great natural, ecological, social and economic importance for Western Greece, since it has the longest and highest flow rate watercourse in the Peloponnisos region. Moreover, the river basin was exposed in the last decades to a plethora of environmental stresses (e.g. hydrogeological alterations, intensively irrigated agriculture, surface and groundwater overexploitation and infrastructure developments), resulting in the degradation of its quantitative and qualitative characteristics. As in most Mediterranean countries, water resource management in Alfeios River Basin has been focused up to now on an essentially supply-driven approach. It is still characterized by a lack of effective operational strategies. Authority responsibility relationships are fragmented, and law enforcement and policy implementation are weak. The present regulated water allocation puzzle entails a mixture of hydropower generation, irrigation, drinking water supply and recreational activities. Under these conditions its water resources management is characterised by high uncertainty and by vague and imprecise data. The considered methodology has been developed in order to deal with uncertainties expressed as either probability distributions, or/and fuzzy boundary intervals, derived by associated α-cut levels. In this framework a set of deterministic submodels is studied through linear programming. The ad hoc water resources management and alternative management patterns in an Alfeios subbasin are analyzed and evaluated under various scenarios, using the above mentioned methodology, aiming to promote a sustainable and equitable water management. Li, Y.P., Huang, G.H. and S.L., Nie, (2010), Planning water resources

  6. Data for NASA's AVE 3 experiment: 25-mb sounding data and synoptic charts. [investigation of atmospheric parameters detected from satellite data under conditions of heavy snow cover

    NASA Technical Reports Server (NTRS)

    Fuelberg, H. E.; Turner, R. E.

    1975-01-01

    The atmospheric variability experiment (AVE 3) is described and tabulated rawinsonde data at 25-mb intervals from the surface to 25 mb for the 41 stations is presented. The experiment was conducted between February 6 and February 7, 1975. Brief discussions are given on methods of data processing, changes in the reduction scheme since the AVE 2 pilot experiment, and data accuracy. An example of contact data is presented as well as synoptic charts prepared from the data.

  7. Medical education in Greece.

    PubMed

    Georgantopoulou, Catherine

    2009-01-01

    This paper aims to present an overview of current medical education in Greece. Greece has a centuries-long tradition in practising and teaching medicine. Medical training, although rigorous, is particularly humane. All Medical Schools in Modern Greece are currently, undergoing a series of changes in an effort to modernize training. The medical education system is also getting harmonized to European Standards for Higher Education, relating to Undergraduate, Postgraduate and Continuous Medical Education of doctors. A specific strength of the Greek educational system is its ethos that emphasises good working conditions and excellent support and supervision at all levels. The current overhauls in Higher Education occupy students, academics and the society at large. Political issues, such as accountability, regulation and autonomy of academia are generating debate. The two-cycle, Bachelor-Master, Undergraduate Model, as described in the Bologna Declaration is still to be implemented. Quality control measures are currently introduced in all academic sectors. PMID:19253151

  8. Effects of Socioeconomic Status on Television Viewing Conditions of Preschoolers in Northern Greece

    ERIC Educational Resources Information Center

    Natsiopoulou, Triantafillia; Melissa-Halikiopoulou, Chrisoula

    2009-01-01

    The purpose of this study was to identify the effects of television (TV) on preschoolers, their TV viewing patterns and the conditions under which they watch TV, taking into consideration their different socioeconomic and regional backgrounds. The survey instrument was a questionnaire with 23 closed-ended questions, given to parents whose children…

  9. Synoptic Flow Interactions in Complex Terrain

    NASA Astrophysics Data System (ADS)

    Hocut, C. M.; Silver, Z.; Wang, Y.; Creegan, E.; Felton, M.; Hoch, S.; Fernando, H. J.; Di Sabatino, S.; Leo, L.; Dimitrova, R.; Zsedrovits, T.; Pardyjak, E.; Huynh, G.

    2014-12-01

    In the spring of 2013, the Mountain Terrain Atmospheric Modeling and Observations Program (MATERHORN) conducted its second extensive field experiment at the Granite Mountain Atmospheric Science Testbed (GMAST), US Army Dugway Proving Grounds (DPG), Utah. Of particular interest to MATERHORN-X-2 were synoptic dominated conditions in which synoptic flows interacted with thermal circulations and the topography leading to modulations of the thermal circulations and external-flow generated lee and progressive waves and if the Froude number was low; eddies, large vortices, wakes and waves developed in the lee of Granite Mountain. To capture these phenomena, a suite of advanced instrumentation was used, which could characterize the upstream unmodified synoptic approach flow and identify the synoptic flow / mountain interactions. In addition to meteorological towers, Doppler LiDARs, placed at two locations to the east and in the lee of Granite Mountain were particularly useful, showing the horizontal spatial pattern and temporal evolution of the synoptic generated phenomena. WRF simulations were used to provide analysis guidance. This research was funded by Office of Naval Research Grant # N00014-11-1-0709 and the Air Force Weather Agency.

  10. Human thermal bioclimatic conditions associated with acute cardiovascular syndromes in Crete Island, Greece

    NASA Astrophysics Data System (ADS)

    Bleta, Anastasia G.; Nastos, Panagiotis T.

    2013-04-01

    The aim of this study is to quantify the association between bioclimatic conditions and daily counts of admissions for non-fatal acute cardiovascular (acute coronary syndrome, arrhythmia, decompensation of heart failure) syndromes (ACS) registered by the two main hospitals in Heraklion, Crete Island, during a five-year period 2008-2012. The bioclimatic conditions analyzed are based on human thermal bioclimatic indices such as the Physiological Equivalent Temperature (PET) and the Universal Thermal Climate Index (UTCI). Mean daily meteorological parameters, such as air temperature, relative humidity, wind speed and cloudiness, were acquired from the meteorological station of Heraklion (Hellenic National Meteorological Service). These parameters were used as input variables in modeling the aforementioned thermal indices, in order to interpret the grade of the thermo-physiological stress. The PET and UTCI analysis was performed by the use of the radiation and bioclimate model, "RayMan", which is well-suited to calculate radiation fluxes and human biometeorological indices. Generalized linear models (GLM) were applied to time series of daily numbers of outpatients with ACS against bioclimatic variations, after controlling for possible confounders and adjustment for season and trends. The interpretation of the results of this analysis suggests a significant association between cold weather and increased coronary heart disease incidence, especially in the elderly and males. Additionally, heat stress plays an important role in the configuration of daily ACS outpatients, even in temperate climate, as that in Crete Island. In this point it is worth mentioning that Crete Island is frequently affected by Saharan outbreaks, which are associated in many cases with miscellaneous phenomena, such as Föhn winds - hot and dry winds - causing extreme bioclimatic conditions (strong heat stress). Taking into consideration the projected increased ambient temperature in the future, ACS

  11. Inferring fault mechanical conditions from the source parameters of a complex microseismic multiplet in the Corinth rift, Greece

    NASA Astrophysics Data System (ADS)

    Dublanchet, P.; Godano, M.; Bernard, P.

    2015-11-01

    We develop a mechanical model of tight clusters of coplanar seismic asperities, to investigate a particular microearthquake swarm located at 8 km depth in the Corinth rift in Greece, which was active between 2001 and 2007. Although it is classified as a multiplet based on waveform similarity, this seismic sequence is much more complex than a repeating earthquake sequence and cannot be interpreted as the regular failure of a single asperity forced by surrounding aseismic creep. Here we suggest that such complex sequences could be generated by the failure of a set of coplanar asperities interacting in a small region of a fault segment. We show that in order to reproduce the dynamics of the observed sequence and the characteristics of the events, the cluster of asperities has to be located very close to an aseismically slipping fault segment, which could be an updip extension of the deep detachment zone in the rift, creeping at 1.5 cm/yr. For more general cases of coplanar clustered asperities, we show that the shape of the cumulative coseismic displacement pattern associated with the repeated failures of the asperities is strongly controlled by the behavior of the fault area surrounding the asperity cluster. In particular, if the cluster is part of a locked fault area, the resulting long-term cumulative displacement is maximum at the center of the cluster. In contrast, an asperity cluster surrounded by aseismic creep leads to a uniform cumulative coseismic slip pattern. The ratio between cumulative slip at the center of the seismogenic patch and cumulative slip at its periphery could therefore be an indicator of the mechanical conditions prevailing on the fault. A systematic study of the source parameters of complex microseismic sequences could therefore provide insights into the mechanical state of active faults continuously generating microseismicity.

  12. Modeling and in situ measurements of biometeorological conditions in microenvironments within the Athens University Campus, Greece

    NASA Astrophysics Data System (ADS)

    Nastos, Panagiotis T.; Polychroni, Iliana D.

    2016-02-01

    The objective of this research is to assess and analyze the biometeorological perception in complex microenvironments in the Athens University Campus (AUC) using urban micromodels, such as RayMan. The human thermal sensation in such a place was considered of great significance due to the great gathering of student body and staff of the University. The quantification of the biometeorological conditions was succeeded by the estimation of the physiologically equivalent temperature (PET), which is a biometeorological index based on the human energy balance. We carried out, on one hand, field measurements of air temperature, relative humidity, wind speed, and global solar irradiance for different sites (building atrium, open area, and green atrium) of the examined microurban environment in order to calculate PET during January-July 2013. Additionally, on the other hand, PET modeling was performed using different sky-view factors and was compared to a reference site (meteorological station of Laboratory of Climatology and Atmospheric Environment, University of Athens). The global radiation was transferred to the examined sites with the RayMan model, which considers the sky-view factors for the adaptation of the radiation fluxes to simple and complex environments. The results of this study reveal the crucial importance of the existence of trees and green cover in a complex environment, as a factor that could be the solution to the efforts of stake holders in order to mitigate strong heat stress and improve people's living quality in urban areas.

  13. Assessing Future Changes in Extreme Precipitation Conditions over Greece: An Investigation of their Links with Circulation Types.

    NASA Astrophysics Data System (ADS)

    Tolika, K.; Anangostopoulou, C.; Tegoulias, I.; Vafiadis, M.

    2010-09-01

    The relationship between the extreme precipitation events and the prevailing circulation types during their occurrence is analyzed in the present study, for four of the biggest cities in Greece (Athens, Thessaloniki, Patra and Heraklio). Daily precipitation data covering the time period 1958-2000 are utilized and the extreme rainfall events are defined using the 95% percentile index. A new automatic classification was applied for the computation of the daily calendar of the circulation types. The main improvements of this classification are the number of the circulation types, which are reduced now to twelve (12) and the fact that the scheme is flexible all over the Mediterranean. The 500hPa geopotential data (2.5 o x 2.5o spatial resolution) from the NCEP/NCAR were employed, covering a large spatial window over the whole European region, for the development of the daily circulation type’s calendar. From the first results of the study it was found that two cyclonic types were the prevailing ones during extreme rainfall conditions. Further more grid point daily precipitation data (the ones closer to the four stations) derived from the most updated regional climate models were also applied in the study for a reference period 1961-1990. The simulated extreme precipitation events were evaluated in comparison to the observational data and a new circulation type calendar was computed this time using the RCMs 500hPa data. Overall, changes both in the magnitude and in the frequency of occurrence of the extreme events were detected. The final goal of the study was to asses the future changes of rainfall extremes as well as the changes of their links with the circulation types as a consequence of the enhanced greenhouse gas concentrations until the end of the 21st century. The aforementioned methodology was applied using the RCM output, both daily precipitation and geopotentials at 500hPa level, (forced by the emission scenario A1B), for the last thirty years of the

  14. Impact of irrigations on simulated convective activity over Central Greece: A high resolution study

    NASA Astrophysics Data System (ADS)

    Kotsopoulos, S.; Tegoulias, I.; Pytharoulis, I.; Kartsios, S.; Bampzelis, D.; Karacostas, T.

    2014-12-01

    The aim of this research is to investigate the impact of irrigations in the characteristics of convective activity simulated by the non-hydrostatic Weather Research and Forecasting model with the Advanced Research dynamic solver (WRF-ARW, version 3.5.1), under different upper air synoptic conditions in central Greece. To this end, 42 cases equally distributed under the six most frequent upper air synoptic conditions, which are associated with convective activity in the region of interest, were utilized considering two different soil moisture scenarios. In the first scenario, the model was initialized with the surface soil moisture of the ECMWF analysis data that usually does not take into account the modification of soil moisture due to agricultural activity in the area of interest. In the second scenario, the soil moisture in the upper soil layers of the study area was modified to the field capacity for the irrigated cropland. Three model domains, covering Europe, the Mediterranean Sea and northern Africa (d01), the wider area of Greece (d02) and central Greece - Thessaly region (d03) are used at horizontal grid-spacings of 15km, 5km and 1km respectively. The model numerical results indicate a strong dependence of convective spatiotemporal characteristics from the soil moisture difference between the two scenarios. Acknowledgements: This research is co-financed by the European Union (European Regional Development Fund) and Greek national funds, through the action "COOPERATION 2011: Partnerships of Production and Research Institutions in Focused Research and Technology Sectors" (contract number 11SYN_8_1088 - DAPHNE) in the framework of the operational programme "Competitiveness and Entrepreneurship" and Regions in Transition (OPC II, NSRF 2007-2013).

  15. A tornado and waterspout climatology for Greece

    NASA Astrophysics Data System (ADS)

    Sioutas, Michalis V.

    2011-06-01

    The results of a systematic investigation and recording of tornado and waterspout occurrence in Greece for the 10-year period 2000-2009 are presented. This is the first database developed in Greece in an attempt to collect and record comprehensive information about tornadoes, waterspouts, funnel clouds, dust devils and other whirlwind phenomena. The primary research purpose of this database is to search, diagnose and record tornado and waterspout occurrences and identify their morphological and climatological features. Based on the 10-year data, a mean annual number of 1.1 tornadoes per unit area of 10 4 km 2, is depicted for Greece. The seasonality appears differently for various parts, with winter most active tornado season for western Greece and summer for northern Greece. Spatial distribution showed that tornadoes are more frequent over western Greece and the Ionian coasts with a local maximum over northwest Peloponnese. Waterspouts occur in both the Aegean and the Ionian Sea mostly in summer and autumn, with a peak in September, while a considerable geographical maximum is located over north off the shore of Iraklion, Crete Island. A preliminary estimate of probability of tornado occurrence for each of the 51 Greek prefectures plus the Mount Athos area, showed highest values for Kerkyra Island and Elias prefectures, western Greece. Analysis based on intensities as assessed by damage data, indicated that the majority of tornadoes reached T4 of the T-scale or F2 of the F-scale. Short wave trough is found as the most relevant synoptic circulation pattern to tornadic activity. Thermodynamic and wind parameters showed a wide range of values, suggesting that threat levels should be adjusted for various areas since tornadoes and waterspouts can occur in different environments.

  16. Empirical and modeled synoptic cloud climatology of the Arctic Ocean

    NASA Technical Reports Server (NTRS)

    Barry, R. G.; Newell, J. P.; Schweiger, A.; Crane, R. G.

    1986-01-01

    A set of cloud cover data were developed for the Arctic during the climatically important spring/early summer transition months. Parallel with the determination of mean monthly cloud conditions, data for different synoptic pressure patterns were also composited as a means of evaluating the role of synoptic variability on Arctic cloud regimes. In order to carry out this analysis, a synoptic classification scheme was developed for the Arctic using an objective typing procedure. A second major objective was to analyze model output of pressure fields and cloud parameters from a control run of the Goddard Institue for Space Studies climate model for the same area and to intercompare the synoptic climatatology of the model with that based on the observational data.

  17. SYNOPTIC MAPPING OF CHROMOSPHERIC MAGNETIC FLUX

    SciTech Connect

    Jin, C. L.; Harvey, J. W.; Pietarila, A. E-mail: jharvey@nso.edu

    2013-03-10

    We used daily full-disk Ca II 854.2 nm magnetograms from the Synoptic Optical Long Term Investigations of the Sun (SOLIS) facility to study the chromospheric magnetic field from 2006 April through 2009 November. We determined and corrected previously unidentified zero offsets in the SOLIS magnetograms. By tracking the disk passages of stable unipolar regions, the measured net flux densities were found to systematically decrease from the disk center to the limb by a factor of about two. This decrease was modeled using a thin flux tube model with a difference in signal formation height between the center and limb sides. Comparison of photospheric and chromospheric observations shows that their differences are largely due to horizontal spreading of magnetic flux with increasing height. The north polar magnetic field decreased nearly linearly with time during our study period while the south polar field was nearly constant. We used the annual change in the viewing angle of the polar regions to estimate the radial and meridional components of the polar fields and found that the south polar fields were tilted away from the pole. Synoptic maps of the chromospheric radial flux density distribution were used as boundary conditions for extrapolation of the field from the chromosphere into the corona. A comparison of modeled and observed coronal hole boundaries and coronal streamer positions showed better agreement when using the chromospheric rather than the photospheric synoptic maps.

  18. Typical synoptic situations and their impacts on the wintertime air pollution in the Guanzhong basin, China

    NASA Astrophysics Data System (ADS)

    Bei, Naifang; Li, Guohui; Huang, Ru-Jin; Cao, Junji; Meng, Ning; Feng, Tian; Liu, Suixin; Zhang, Ting; Zhang, Qiang; Molina, Luisa T.

    2016-06-01

    Rapid industrialization and urbanization have caused severe air pollution in the Guanzhong basin, northwestern China, with heavy haze events occurring frequently in recent winters. Using the NCEP reanalysis data, the large-scale synoptic situations influencing the Guanzhong basin during wintertime of 2013 are categorized into six types to evaluate the contribution of synoptic situations to the air pollution, including "north-low", "southwest-trough", "southeast-high", "transition", "southeast-trough", and "inland-high". The FLEXPART model has been utilized to demonstrate the corresponding pollutant transport patterns for the typical synoptic situations in the basin. Except for "southwest-trough" and "southeast-high" (defined as favorable synoptic situations), the other four synoptic conditions (defined as unfavorable synoptic situations) generally facilitate the accumulation of air pollutants, causing heavy air pollution in the basin. In association with the measurement of PM2.5 (particulate matter with aerodynamic diameter less than 2.5 µm) in the basin, the unfavorable synoptic situations correspond to high PM2.5 mass concentrations or poor air quality and vice versa. The same analysis has also been applied to winters of 2008-2012, which shows that the basin was mainly influenced by the unfavorable synoptic situations during wintertime leading to poor air quality. The WRF-CHEM model has further been applied to simulate the selected 6 days representing the typical synoptic situations during the wintertime of 2013, and the results generally show a good agreement between the modeled distributions and variations of PM2.5 and the corresponding synoptic situations, demonstrating reasonable classification for the synoptic situations in the basin. Detailed meteorological conditions, such as temperature inversion, low-level horizontal wind speed, and planetary boundary layer, all contribute to heavy air pollution events in the basin under unfavorable synoptic conditions

  19. Harmonic analysis of the precipitation in Greece

    NASA Astrophysics Data System (ADS)

    Nastos, P. T.; Zerefos, C. S.

    2009-04-01

    Greece is a country with a big variety of climates due to its geographical position, to the many mountain ranges and also to the multifarious and long coastline. The mountainous volumes are of such orientation that influences the distribution of the precipitation, having as a result, Western Greece to present great differentiations from Central and Eastern Greece. The application of harmonic analysis to the annual variability of precipitation is the goal of this study, so that the components, which compose the annual variability, be elicited. For this purpose, the mean monthly precipitation data from 30 meteorological stations of National Meteorological Service were used for the time period 1950-2000. The initial target is to reduce the number of variables and to detect structure in the relationships between variables. The most commonly used technique for this purpose is the application of Factor Analysis to a table having as columns the meteorological stations-variables and rows the monthly mean precipitation, so that 2 main factors were calculated, which explain the 98% of total variability of precipitation in Greece. Factor 1, representing the so-called uniform field and interpreting the most of the total variance, refers in fact to the Mediterranean depressions, affecting mainly the West of Greece and also the East Aegean and the Asia Minor coasts. In the process, the Fourier Analysis was applied to the factor scores extracted from the Factor Analysis, so that 2 harmonic components are resulted, which explain above the 98% of the total variability of each main factor, and are due to different synoptic and thermodynamic processes associated with Greece's precipitation construction. Finally, the calculation of the time of occurrence of the maximum precipitation, for each harmonic component of each one of the two main factors, gives the spatial distribution of appearance of the maximum precipitation in the Hellenic region.

  20. Automation of Meudon Synoptic Maps

    NASA Astrophysics Data System (ADS)

    Aboudarham, J.; Scholl, I.; Fuller, N.; Fouesneau, M.; Galametz, M.; Gonon, F.; Maire, A.; Leroy, Y.

    2007-05-01

    Thanks to the automatic solar features detection developed in the frame of the European EGSO (European Grid of Solar Observations) project, an important part of the automation of Meudon Synoptic Maps is achieved. Nevertheless, the tracking of these solar structures over time has still to be done to synthesize their evolution during a Carrington rotation. A new approach to track filaments, based on image segmentation and intersection of regions of interest, gives successful results, This is a major step to move towards a fully automatic building of Meudon Synoptic Maps of Solar Activity.

  1. Synoptic Flow Interactions with an Isolated Mountain in Complex

    NASA Astrophysics Data System (ADS)

    Hocut, C. M.; Creegan, E.; Wang, Y.; Hoch, S.; Silver, Z.; Leo, L. S.; Di Sabatino, S.; Fernando, H. J.; Pardyjak, E.

    2015-12-01

    In the spring of 2013, the Mountain Terrain Atmospheric Modeling and Observations Program (MATERHORN) conducted its second extensive field experiment at the Granite Mountain Atmospheric Science Testbed (GMAST), US Army Dugway Proving Grounds (DPG), Utah. Of particular interest to MATERHORN-X-2 were synoptic dominated conditions in which synoptic flows interacted with the topography leading to external-flow generated lee and progressive waves and if the Froude number was low; development of eddies, large vortices, wakes and waves in the lee of Granite Mountain. To capture these phenomena, a suite of advanced instrumentation was used, which could characterize the upstream unmodified synoptic approach flow and identify the synoptic flow / mountain interactions. In addition to meteorological towers, three Doppler LiDARs, placed at two locations to the east and in the lee of Granite Mountain were particularly useful, showing the horizontal spatial pattern and temporal evolution of the synoptic generated phenomena. WRF simulations were used to provide analysis guidance. This research was funded by Office of Naval Research Grant # N00014-11-1-0709 and the Air Force Weather Agency.

  2. Evaluation of thermal bioclimate based on observational data and numerical simulations: an application to Greece.

    PubMed

    Giannaros, Theodore M; Melas, Dimitrios; Matzarakis, Andreas

    2015-02-01

    The evaluation of thermal bioclimate can be conducted employing either observational or modeling techniques. The advantage of the numerical modeling approach lies in that it can be applied in areas where there is lack of observational data, providing a detailed insight on the prevailing thermal bioclimatic conditions. However, this approach should be exploited carefully since model simulations can be frequently biased. The aim of this paper is to examine the suitability of a mesoscale atmospheric model in terms of evaluating thermal bioclimate. For this, the numerical weather prediction Weather Research and Forecasting (WRF) model and the radiation RayMan model are employed for simulating thermal bioclimatic conditions in Greece during a 1-year time period. The physiologically equivalent temperature (PET) is selected as an index for evaluating thermal bioclimate, while synoptic weather station data are exploited for verifying model performance. The results of the present study shed light on the strengths and weaknesses of the numerical modeling approach. Overall, it is shown that model simulations can provide a useful alternative tool for studying thermal bioclimate. Specifically for Greece, the WRF/RayMan modeling system was found to perform adequately well in reproducing the spatial and temporal variations of PET. PMID:24771280

  3. Effects of different boundary conditions and palaeotopographies on the onshore response of tsunamis in a numerical model - A case study from western Greece

    NASA Astrophysics Data System (ADS)

    Röbke, B. R.; Schüttrumpf, H.; Vött, A.

    2016-08-01

    Hydrodynamic numerical models are essential in modern tsunami hazard assessment. They allow the economical simulation of possible tsunami scenarios for areas at risk and provide reliable and detailed insights into local onshore dynamics. This is especially true when simulations are calibrated with field traces of past tsunami inundation events. Following this approach, the current study focuses on palaeotsunami events indicated by sedimentary and geomorphological field traces in the northern Gulf of Kyparissia (NW Greece). Based on three different digital elevation models (DEM) - reflecting the recent and two palaeotopographies - various tsunami wave constellations according to the solitary and N-wave theory are numerically simulated. The main objective is to investigate the effects of both, different palaeotopographies and boundary conditions on the tsunami onshore response in the numerical model. Tsunami landfall related to N-waves is found to be considerably stronger compared to solitary waves. This phenomenon, known as the N-wave effect, is demonstrated for the first time in a specific study area. Inundation dynamics are even stronger affected by the different palaeotopographies, which is due to substantial vertical crust movements in the northern Gulf of Kyparissia considered in the palaeo-DEMs. By applying different waveforms and palaeotopographies, the model achieves close agreement with field observations, altogether revealing a significant tsunami hazard for the Gulf of Kyparissia, which is in contrast to conventional numerical studies of the area. The marked differences between the presented scenarios emphasise the need to consider a wide variety of possible hydrodynamic boundary conditions and probable topographical conditions in order to find scenarios in plausible accordance with palaeotsunami field traces. Once a plausible scenario is found it can be applied to the recent topography in view of a reliable modern hazard assessment.

  4. An investigation of relationships between meso- and synoptic-scale phenomena

    NASA Technical Reports Server (NTRS)

    Scoggins, J. R.; Wood, J. E.; Fuelberg, H. E.; Read, W. L.

    1972-01-01

    Methods based on the vorticity equation, the adiabatic method, the curvature of the vertical wind profile, and the structure of synoptic waves are used to determine areas of positive vertical motion in the mid-troposphere for a period in each season. Parameters indicative of low-level moisture and conditional instability are areas in which mesoscale systems may be present. The best association between mesoscale and synoptic-scale phenomena was found for a period during December when synoptic-scale systems were well developed. A good association between meso- and synoptic-scale events also was found for a period during March, while the poorest association was found for a June period. Daytime surface heating apparently is an important factor in the formation of mesoscale systems during the summer. It is concluded that the formation of mesoscale phenomena may be determined essentially from synoptic-scale conditions during winter, late fall, and early spring.

  5. Synoptic climatology of major floods in the Negev Desert, Israel

    NASA Astrophysics Data System (ADS)

    Kahana, Ron; Ziv, Baruch; Enzel, Yehouda; Dayan, Uri

    2002-06-01

    This study examines the extent to which the floods in the Negev Desert, an area that constitutes the southern half of Israel, are not the outcome of purely local weather conditions but are, rather, the result of distinct synoptic-scale events. This was done through compiling and analysing a hydro-climatological database of all the major floods in the Negev, and then categorizing them manually into synoptic types that cause the major floods.The type analysis is based on the US National Meteorological Center data sets with 2.5° × 2.5° resolution analysed by GrADS. Data were compiled and studied for 52 floods for the period 1965-94, with peak discharge above the magnitude of 5 year recurrence intervals (RI > 5 years) in at least one drainage basin.Distinct extreme synoptic patterns are indeed associated with 42 of the 52 floods. They were grouped into four synoptic types, two of which were associated with 37 events: (a) an active Red Sea trough, defined as a surface trough extending from East Africa through the Red Sea toward the eastern Mediterranean, accompanied by a pronounced trough at the 500 hPa level over eastern Egypt: (b) a Syrian low, defined as a well-developed Mediterranean cyclone accompanied by a pronounced upper-level trough, both located over Syria. Each of the four synoptic types has its own evolution course, and a unique seasonal and spatial distribution of its associated flooded basins.These findings imply that the major floods in the Negev can be considered as signatures of exceptional synoptic-scale evolutions, and that major floods reflect extreme climatic events. Our results indicate that it is possible to use a set of dynamic and thermodynamic variables for predicting the occurrence and location of major flash floods.

  6. A Networked Desktop Synoptic Laboratory.

    NASA Astrophysics Data System (ADS)

    Ramamurthy, Mohan K.; Bowman, Kenneth P.; Jewett, Brian F.; Kemp, John G.; Kline, Charles

    1992-07-01

    Over the past several years, the Department of Atmospheric Sciences at the University of Illinois has developed a computerized weather laboratory that permits interactive access to real-time data from observing sites around the United States and to output from numerical weather prediction models at the operational centers. Such a setup, with timely access to observations and numerical model forecasts from any networked terminal, personal computer, or workstation, is a valuable tool for education and research in meteorology. The University of Illinois system acts as a real-time, on-line, in-class instructional meteorology laboratory for students. The data-display software is based on the X-windows protocol, which is network transparent and system independent.In addition to software packages distributed by the University Data Project (UNIDATA), software tools developed by the National Center for Supercomputing Applications and the University of Illinois are used to display, animate, and manipulate conventional maps, satellite images, and radar summaries. The underlying idea is to bring every product from a traditional synoptic laboratory to any desktop computer residing on the network.An overview of the University of Illinois prototype for a paperless, desktop synoptic lab, together with the details of the hardware and software involved, is presented here, along with some examples of its use in teaching and research.

  7. Adult Education in Greece

    ERIC Educational Resources Information Center

    Kokkos, Alexios

    2008-01-01

    The central aim of this article is to analyse the current situation of adult education in Greece. The article focuses on the following points: (a) the degree of participation in programmes of continuing professional training and general adult education courses, (b) the quality and the outcomes of the adult education provision in Greece, and (c)…

  8. Contrasting environments associated with storm prediction center tornado outbreak forecasts using synoptic-scale composite analysis

    NASA Astrophysics Data System (ADS)

    Bates, Alyssa Victoria

    Tornado outbreaks have significant human impact, so it is imperative forecasts of these phenomena are accurate. As a synoptic setup lays the foundation for a forecast, synoptic-scale aspects of Storm Prediction Center (SPC) outbreak forecasts of varying accuracy were assessed. The percentages of the number of tornado outbreaks within SPC 10% tornado probability polygons were calculated. False alarm events were separately considered. The outbreaks were separated into quartiles using a point-in-polygon algorithm. Statistical composite fields were created to represent the synoptic conditions of these groups and facilitate comparison. Overall, temperature advection had the greatest differences between the groups. Additionally, there were significant differences in the jet streak strengths and amounts of vertical wind shear. The events forecasted with low accuracy consisted of the weakest synoptic-scale setups. These results suggest it is possible that events with weak synoptic setups should be regarded as areas of concern by tornado outbreak forecasters.

  9. Fjord water circulation patterns and dysoxic/anoxic conditions in a Mediterranean semi-enclosed embayment in the Amvrakikos Gulf, Greece

    NASA Astrophysics Data System (ADS)

    Ferentinos, George; Papatheodorou, George; Geraga, Maria; Iatrou, Margarita; Fakiris, Elias; Christodoulou, Dimitris; Dimitriou, Evagelos; Koutsikopoulos, Constantin

    2010-08-01

    Oceanographic research in the Amvrakikos Gulf in Western Greece, a semi-enclosed embayment isolated from the Ionian Sea by a narrow, shallow sill, has shown that it is characterised by a fjord-like oceanographic regime. The Gulf is characterised by a well-stratified two layer structure in the water column made up of a surface layer and a bottom layer that are separated by a strong pycnocline. At the entrance over the sill, there is a brackish water outflow in the surface water and a saline water inflow in the near-bed region. This morphology and water circulation pattern makes the Amvrakikos Gulf the only Mediterranean Sea fjord. The investigations have also shown that the surface layer is well oxygenated, whereas in the pycnocline, the dissolved oxygen (DO) declines sharply and finally attains a value of zero, thus dividing the water column into oxic, dysoxic and anoxic environments. At the dysoxic/anoxic interface, at a depth of approximately 35 m, a sharp redox cline develops with Eh values between 0 and 120 mV occurring above and values between 0 and -250 mV occurring below, where oxic and anoxic biochemical processes prevail, respectively. On the seafloor underneath the anoxic waters, a black silt layer and a white mat cover resembling Beggiatoa-like cells are formed. The dysoxic/anoxic conditions appeared during the last 20 to 30 years and have been caused by the excessive use of fertilisers, the increase in animal stocks, intensive fish farming and domestic effluents. The inflicted dysoxia/anoxia has resulted in habitat loss on the seafloor over an area that makes up just over 50% of the total Gulf area and approximately 28% of the total water volume. Furthermore, anoxia is also considered to have been responsible for the sudden fish mortality which occurred in aquaculture rafts in the Gulf in February 2008. Therefore, anoxic conditions can be considered to be a potential hazard to the ecosystem and to the present thriving fishing and mariculture industry in

  10. Synoptic Spectrophotometry Enabled by SMARTS

    NASA Astrophysics Data System (ADS)

    Walter, Frederick M.

    2011-05-01

    The photometric record for many types of astrophysical objects is remarkably fecund, due to a growing body of synoptic photometric surveys. The same cannot be said for the spectroscopic record, despite the fact that much of the astrophysics requires spectroscopy, rather than photometry, to decipher. I shall report on selected topics I've been studying over the past 7 years, using the SMARTS/CTIO 1.5m telescope to obtain long time series on interesting stars. The venerable RC spectrograph offers resolutions from 300 to 3000 km/s, and can obtain useful spectra from magnitudes 0 to 18 (for emission line objects) in less than an hour. The capabilities of the echelle spectrograph greatly expand the scope of the science. I shall touch on science topics ranging from long term evolution of classical and recurrent novae, the accretion-induced activity in T Tauri stars and cataclysmic variables, to the orbits of O stars.

  11. Santorini, Greece

    NASA Technical Reports Server (NTRS)

    2000-01-01

    This ASTER image of Santorini was acquired on November 21, 2000 and covers an area of 18 by 18 km. The eruption of Santorini in 1650 B.C. was one of the largest in the last 10,000 years. About 30 cubic kilometers of magma was erupted, forming a plinian column 36 km high. The removal of such a large volume of magma caused the volcano to collapse, producing a caldera. Ash fell over a large area of the eastern Mediterranean. The eruption probably caused the end of the Minoan civilization on the island of Crete. The largest island is Thera, and the smaller is Therasia. The Kameni Islands (dark in the image center) formed after the caldera., with the most recent eruptions occurring in 1950.

    The image is centered at 36.4 degrees north latitude, 25.4 degrees east longitude.

    Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) is one of five Earth-observing instruments launched December 18, 1999, on NASA's Terra satellite. The instrument was built by Japan's Ministry of International Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and the data products. Dr. Anne Kahle at NASA's Jet Propulsion Laboratory, Pasadena, Calif., is the U.S. Science team leader; Moshe Pniel of JPL is the project manager. ASTER is the only high resolution imaging sensor on Terra. The primary goal of the ASTER mission is to obtain high-resolution image data in 14 channels over the entire land surface, as well as black and white stereo images. With revisit time of between 4 and 16 days, ASTER will provide the capability for repeat coverage of changing areas on Earth's surface.

    The broad spectral coverage and high spectral resolution of ASTER will provide scientists in numerous disciplines with critical information for surface mapping, and monitoring dynamic conditions and temporal change. Example applications are: monitoring glacial advances and retreats, monitoring potentially active volcanoes

  12. 62 FR 61036 - Changes in Disease Status of Belgium, France, Greece, Luxembourg, Portugal, and Spain

    Federal Register 2010, 2011, 2012, 2013, 2014

    1997-11-14

    ... specified conditions, based on the regions' disease status (see 62 FR 56000-56033, October 28, 1997, Dockets..., Greece, Luxembourg, Portugal, and Spain AGENCY: Animal and Plant Health Inspection Service, USDA. ACTION...-mouth disease; Greece free of rinderpest; France, Greece, Luxembourg, and Spain free of exotic...

  13. Synoptic-scale behavior of the extratropical tropopause inversion layer

    NASA Astrophysics Data System (ADS)

    Pilch Kedzierski, Robin; Matthes, Katja; Bumke, Karl

    2015-11-01

    High-resolution GPS radio occultation temperature profiles from the COSMIC satellite mission (2007-2013) are used to obtain daily snapshots of the strength of the extratropical tropopause inversion layer (TIL). Its horizontal structure and day-to-day variability are linked to the synoptic situation at near-tropopause level. The strength of the TIL in cyclonic as well as anticyclonic conditions is investigated by separating relative vorticity into curl and shear terms. The analysis shows that the TIL has high zonal variability, and its strength is instantaneously adjusted to the synoptic situation at near-tropopause level. Our key finding is that the TIL within midlatitude ridges in winter is as strong as or stronger than the TIL in polar summer. The strongest TIL in anticyclonic conditions is related to the shear term, while the weaker TIL in cyclonic conditions is enhanced by the curl term.

  14. Using synoptic weather types to predict visitor attendance at Atlanta and Indianapolis zoological parks

    NASA Astrophysics Data System (ADS)

    Perkins, David R.

    2016-02-01

    Defining an ideal "tourism climate" has been an often-visited research topic where explanations have evolved from global- to location-specific indices tailored to tourists' recreational behavior. Unfortunately, as indices become increasingly specific, they are less translatable across geographies because they may only apply to specific activities, locales, climates, or populations. A key need in the future development of weather and climate indices for tourism has been a translatable, meteorologically based index capturing the generalized ambient atmospheric conditions yet considering local climatology. To address this need, this paper tests the applicability of the spatial synoptic classification (SSC) as a tool to predict visitor attendance response in the tourism, recreation, and leisure (TRL) sector across different climate regimes. Daily attendance data is paired with the prevailing synoptic weather condition at Atlanta and Indianapolis zoological parks from September 2001 to June 2011, to review potential impacts ambient atmospheric conditions may have on visitor attendances. Results indicate that "dry moderate" conditions are most associated with high levels of attendance and "moist polar" synoptic conditions are most associated with low levels of attendance at both zoological parks. Comparing visitor response at these zoo locations, visitors in Indianapolis showed lower levels of tolerance to synoptic conditions which were not "ideal." Visitors in Indianapolis also displayed more aversion to "polar" synoptic regimes while visitors in Atlanta displayed more tolerance to "moist tropical" synoptic regimes. Using a comprehensive atmospheric measure such as the SSC may be a key to broadening application when assessing tourism climates across diverse geographies.

  15. Fire in Southern Greece

    NASA Technical Reports Server (NTRS)

    2007-01-01

    The last major fire in southern Greece was brought under control this weekend, but not until over 469,000 acres of mostly forest and farmland were destroyed. An estimated 4000 people lost their homes, and over 60 deaths were reported. These were the worst fires ever to occur in Greece. In this Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) image acquired September 4 over the western coast of the Peloponnesus Peninsula, burned areas appear in dark red, and unburned vegetation is green. The area includes the ancient site of Olympia, the site of the Olympic Games in classical times. The fires came within 2 kilometers (1.2 miles) of the archaeological site, but spared it.

    With its 14 spectral bands from the visible to the thermal infrared wavelength region, and its high spatial resolution of 15 to 90 meters (about 50 to 300 feet), ASTER images Earth to map and monitor the changing surface of our planet.

    ASTER is one of five Earth-observing instruments launched December 18, 1999, on NASA's Terra spacecraft. The instrument was built by Japan's Ministry of Economy, Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and the data products.

    The broad spectral coverage and high spectral resolution of ASTER provides scientists in numerous disciplines with critical information for surface mapping, and monitoring of dynamic conditions and temporal change. Example applications are: monitoring glacial advances and retreats; monitoring potentially active volcanoes; identifying crop stress; determining cloud morphology and physical properties; wetlands evaluation; thermal pollution monitoring; coral reef degradation; surface temperature mapping of soils and geology; and measuring surface heat balance.

    The U.S. science team is located at NASA's Jet Propulsion Laboratory, Pasadena, Calif. The Terra mission is part of NASA's Science Mission Directorate.

    Size: 56.4 by

  16. Synoptic Solar Magnetic Fields: Explored and Predicted

    NASA Astrophysics Data System (ADS)

    Lundstedt, H.; Wik, M.; Wintoft, P.

    2006-12-01

    Solar synoptic maps provide an important visualization of global patterns. Maps are available of sub-surface flows, photospheric and coronal magnetic fields. We have carried out a multiresolution analysis (MRA) of longitudinally averaged synoptic magnetograms. The magnetograms were observed at Wilcox Solar Observatory (WSO), Stanford and with Michelson Doppler Imager (MDI) onboard SOHO of ESA/NASA. We performed a multilevel wavelet decomposition of the solar magnetic field signal for each latitude. Trends and periods in the decomposed signal are shown. Solar cycle 24 is discussed. Predictions of the synoptic magnetic fields, using neural networks, have been developed. With the launch of Solar Dynamics Observatory (SDO), real-time synoptic maps will be available. That would be of great importance for real-time predictions of space weather effects.

  17. Springtime cloud properties in the Taiwan Strait: synoptic controls and local processes

    NASA Astrophysics Data System (ADS)

    Kueh, Mien-Tze; Lin, Pay-Liam

    2014-05-01

    This paper examines the springtime cloud properties in the Taiwan Strait (TS), with emphases on their dependence on synoptic controls and local processes, using a suite of in situ and remote sensing observations. Cloud properties in the TS are inferred from a combination of MODIS and in situ observations and further classified into two synoptic conditions: continental cold air surge and frontal system. The study reveals a predominance of synoptic-scale controls in regulating the cloud properties in the TS. The sensitivity of clouds to the local thermodynamic mechanisms as well as the underlying surface conditions is fundamentally dependent on synoptic-scale flow patterns. The springtime clouds over the TS are commonly a mixture of stratocumulus and alto clouds. More precisely, there is a preponderance of stratocumulus over the strait. A preferential occupancy of stratiform alto clouds is recognized during cold air surge, whereas vertical development of cloud layers (mostly the stratocumulus) is commonly observed with frontal passage. The most distinct difference between the local clouds formation associated with the two synoptic conditions is the suppression of very low cloud and fog along with cold air surge. Stratus clouds and fog are present within the northward prefrontal airflow from warmer to colder water sites, along with an increase in stability relating to lower altitudes of boundary layer clouds. Although the rainfall occurrences are about the same for both synoptic conditions, the frontal rain amounts are larger on average.

  18. Synoptic Climatological Approaches to Assessing Subcanopy Hydrologic and Nutrient Fluxes in a Temperate Deciduous Forest

    NASA Astrophysics Data System (ADS)

    Siegert, C. M.; Levia, D. F.; Leathers, D. J.

    2012-12-01

    The partitioning of precipitation incident to a forest canopy into throughfall and stemflow is controlled by biotic and abiotic factors. Biotic factors include canopy architecture, bark and leaf morphology, and leaf presence whereas abiotic factors include precipitation, antecedent moisture conditions, and wind speed. Previous studies relating the subcanopy hydrologic flux to storm events consider the aforementioned abiotic factors at the event level. This research applies atmospheric classification methods from the field of synoptic climatology to relate large scale weather patterns to local forest hydrologic conditions. A daily synoptic calendar is employed to categorize the observed subcanopy hydrologic flux during storm events and is evaluated as a tool for historical reconstruction and future prediction of forest hydrologic conditions as precipitation regimes are influenced by climate change. At the seasonal scale, the majority of precipitation occurs in 4 out of 13 synoptic types in winter, 4 out of 13 in spring, 2 out of 9 in summer, and 5 out of 11 in autumn, the remaining synoptic types are dominated by fair weather conditions (although small precipitation amounts are sometimes observed). During the study period, precipitation is correctly predicted by synoptic types 82% of the time in winter, 70% in spring, 88% in summer, and 73% in autumn. Analysis of variance (ANOVA) indicates that spring, summer, and fall precipitation-producing synoptic types predict statistically different subcanopy throughfall fluxes. The absence of foliage and more homogenous winter canopy may diminish the predictive ability of synoptic typing in regards to throughfall at that time of year. Biogeochemical canopy fluxes associated with storm events are also distinguishable using the synoptic calendar.

  19. Nucleation in Synoptically Forced Cirrostratus

    NASA Technical Reports Server (NTRS)

    Lin, R.-F.; Starr, D. OC.; Reichardt, J.; DeMott, P. J.

    2004-01-01

    Formation and evolution of cirrostratus in response to weak, uniform and constant synoptic forcing is simulated using a one-dimensional numerical model with explicit microphysics, in which the particle size distribution in each grid box is fully resolved. A series of tests of the model response to nucleation modes (homogeneous-freezing-only/heterogeneous nucleation) and heterogeneous nucleation parameters are performed. In the case studied here, nucleation is first activated in the prescribed moist layer. A continuous cloud-top nucleation zone with a depth depending on the vertical humidity gradient and one of the nucleation parameters is developed afterward. For the heterogeneous nucleation cases, intermittent nucleation zones in the mid-upper portion of the cloud form where the relative humidity is on the rise, because existent ice crystals do not uptake excess water vapor efficiently, and ice nuclei (IN) are available. Vertical resolution as fine as 1 m is required for realistic simulation of the homogeneous-freezing-only scenario, while the model resolution requirement is more relaxed in the cases where heterogeneous nucleation dominates. Bulk microphysical and optical properties are evaluated and compared. Ice particle number flux divergence, which is due to the vertical gradient of the gravity-induced particle sedimentation, is constantly and rapidly changing the local ice number concentration, even in the nucleation zone. When the depth of the nucleation zone is shallow, particle number concentration decreases rapidly as ice particles grow and sediment away from the nucleation zone. When the depth of the nucleation zone is large, a region of high ice number concentration can be sustained. The depth of nucleation zone is an important parameter to be considered in parametric treatments of ice cloud generation.

  20. The Large Synoptic Survey Telescope

    NASA Astrophysics Data System (ADS)

    Ivezic, Zeljko

    2007-05-01

    The Large Synoptic Survey Telescope (LSST) is currently by far the most ambitious proposed ground-based optical survey. With initial funding from the US National Science Foundation (NSF), Department of Energy (DOE) laboratories and private sponsors, the design and development efforts are well underway at many institutions, including top universities and leading national laboratories. The main science themes that drive the LSST system design are Dark Energy and Matter, the Solar System Inventory, Transient Optical Sky and the Milky Way Mapping. The LSST system, with its 8.4m telescope and 3,200 Megapixel camera, will be sited at Cerro Pachon in northern Chile, with the first light scheduled for 2014. In a continuous observing campaign, LSST will cover the entire available sky every three nights in two photometric bands to a depth of V=25 per visit (two 15 second exposures), with exquisitely accurate astrometry and photometry. Over the proposed survey lifetime of 10 years, each sky location would be observed about 1000 times, with the total exposure time of 8 hours distributed over six broad photometric bandpasses (ugrizY). This campaign will open a movie-like window on objects that change brightness, or move, on timescales ranging from 10 seconds to 10 years, and will produce a catalog containing over 10 billion galaxies and a similar number of stars. The survey will have a data rate of about 30 TB/night, and will collect over 60 PB of raw data over its lifetime, resulting in an incredibly rich and extensive public archive that will be a treasure trove for breakthroughs in many areas of astronomy and astrophysics.

  1. The Large Synoptic Survey Telescope

    NASA Astrophysics Data System (ADS)

    Axelrod, T. S.

    2006-07-01

    The Large Synoptic Survey Telescope (LSST) is an 8.4 meter telescope with a 10 square degree field degree field and a 3 Gigapixel imager, planned to be on-sky in 2012. It is a dedicated all-sky survey instrument, with several complementary science missions. These include understanding dark energy through weak lensing and supernovae; exploring transients and variable objects; creating and maintaining a solar system map, with particular emphasis on potentially hazardous objects; and increasing the precision with which we understand the structure of the Milky Way. The instrument operates continuously at a rapid cadence, repetitively scanning the visible sky every few nights. The data flow rates from LSST are larger than those from current surveys by roughly a factor of 1000: A few GB/night are typical today. LSST will deliver a few TB/night. From a computing hardware perspective, this factor of 1000 can be dealt with easily in 2012. The major issues in designing the LSST data management system arise from the fact that the number of people available to critically examine the data will not grow from current levels. This has a number of implications. For example, every large imaging survey today is resigned to the fact that their image reduction pipelines fail at some significant rate. Many of these failures are dealt with by rerunning the reduction pipeline under human supervision, with carefully ``tweaked'' parameters to deal with the original problem. For LSST, this will no longer be feasible. The problem is compounded by the fact that the processing must of necessity occur on clusters with large numbers of CPU's and disk drives, and with some components connected by long-haul networks. This inevitably results in a significant rate of hardware component failures, which can easily lead to further software failures. Both hardware and software failures must be seen as a routine fact of life rather than rare exceptions to normality.

  2. Synoptic events force biological productivity in Patagonian fjord ecosystems

    NASA Astrophysics Data System (ADS)

    Daneri, Giovanni

    2016-04-01

    The annual cycle of primary productivity of the Patagonian fjords has, to date, been described as a two phase system consisting of a short non productive winter phase (during June and July) and a productive phase extending from late winter (August) to autumn (May). Low levels of primary production, phytoplankton biomass and high concentrations of surface nutrients have been described as characterizing winter conditions while pulsed productivity events typifies the productivity pattern during the extended productive season. Pulsed productivity events characterize coastal waters where inorganic nutrients in surface layers are replenished following periods of intensive utilization by autotrophs. Freshwater input in Patagonian fjords in southern Chile (41-55°S) results in one of the largest estuarine regions worldwide. Here strong haline water column stratification prevents nutrient mixing to the surface layers thus potentially shutting off algal production. Our working hypothesis considered that in order to reconcile the observed pulsed productivity pattern, periodic breaking (associated to surface nutrient replenishment) and re-establishment of estuarine conditions (associated to water column stratification) would be required. Up to now however our understanding of the physical processes that control water column conditions in the Patagonian fjord area has been extremely limited. Here we present evidence linking the passage of synoptic low pressure fronts to pulsed productivity events in the Patagonian fjord area. These front controls and influence local processes of interaction between the fjord and the atmosphere generating a rapid water column response. In the specific case of the Puyuhuapi fjord we have been able to show that such synoptic fronts induce surface flow reversal and water column mixing. Phytoplankton blooming occurs after the passage of the synoptic front once calmer conditions prevail and estuarine conditions are re established. The occurrence of

  3. English Language Teaching in Greece.

    ERIC Educational Resources Information Center

    Adoniou, Misty

    2001-01-01

    Highlights English language teaching in Greece, both in the government school system and in private English language education, focusing on the teachers, the classrooms, the classroom and syllabus, and inservice support. Discusses English in higher education, opportunities for teachers in Greece, and support for all teachers of English in Greece.…

  4. Statistical evaluation of the simulated convective activity over Central Greece

    NASA Astrophysics Data System (ADS)

    Kartsios, Stergios; Kotsopoulos, Stylianos; Karacostas, Theodore S.; Tegoulias, Ioannis; Pytharoulis, Ioannis; Bampzelis, Dimitrios

    2015-04-01

    In the framework of the project DAPHNE (www.daphne-meteo.gr), the non-hydrostatic Weather Research and Forecasting model with the Advanced Research dynamic solver (WRF-ARW, version 3.5.1) is used to produce very high spatiotemporal resolution simulations of the convective activity over Thessaly plain and hence, enhancing our knowledge on the impact of high resolution elevation and land use data in the moist convection. The expecting results act as a precursor for the potential applicability of a planned precipitation enhancement program. The three model domains, covering Europe, the Mediterranean Sea and northern Africa (d01), the wider area of Greece (d02) and Thessaly region-central Greece (d03), are used at horizontal grid-spacings of 15km, 5km and 1km respectively. ECMWF operational analyses at 6-hourly intervals (0.25ox0.25o lat.-long.) are imported as initial and boundary conditions of the coarse domain, while in the vertical, 39 sigma levels (up to 50 hPa) are used, with increased resolution in the boundary layer. Microphysical processes are represented by WSM6 scheme, sub-grid scale convection by Kain-Fritsch scheme, longwave and shortwave radiation by RRTMG scheme, surface layer by Monin-Obukhov (MM5), boundary layer by Yonsei University and soil physics by NOAH Unified model. Six representative days with different upper-air synoptic circulation types are selected, while high resolution (3'') elevation data from the Shuttle Radar Topography Mission (SRTM - version 4) are inserted in the innermost domain (d03), along with the Corine Land Cover 2000 raster data (3''x3''). The aforementioned data sets are used in different configurations, in order to evaluate the impact of each one on the simulated convective activity in the vicinity of Thessaly region, using a grid of available meteorological stations in the area. For each selected day, four (4) sensitivity simulations are performed, setting a total number of 24 runs. Finally, the best configuration provides

  5. Synoptic Displays for HBESL and the Laser Lab System

    NASA Astrophysics Data System (ADS)

    Muvandimwe, Didier; Ruan, Jinhao

    2013-04-01

    This project aimed to produce synoptic displays for two experiments: HBESL, the High Brightness Electron Source Laboratory and NML Laser experiment in order to assist the control of these facilities in the accelerator control network of Fermilab. Both displays were successfully produced and added on the ACNET (Accelerator Control Network) page. Synoptic is a system for graphical representation of real-time data in the accelerator control system of Fermilab. It creates diagrams representing a certain machine or process along with actual reading from the control system indicating its current state as well as supporting the ability to set data back from the control system. In this research, I learned how to use this software, and was able to use it in order to build these two synoptic displays for these two experiments: HBESL, and the laser lab. Both displays for HBESL and the laser experiment were successfully produced and added on the ACNET console under the NML page. Having these displays allow both users and scientists to be able to constantly control their experiments anywhere at any time. Being able to read out and set experimental parameters help users to protect the efficiency of experiments as well as avoiding extreme inaccuracy and inadequate conditions of experiments.

  6. Upper-Level Waves of Synoptic Scale at Midlatitudes

    NASA Astrophysics Data System (ADS)

    Rivest, Chantal

    1990-01-01

    . Basic states with positive tropospheric and stratospheric gradients of potential vorticity are found to support upper-level synoptic-scale waves for time scales consistent with observations. Following Farrell (1989), we then identify a class of near optimal initial conditions for the excitation of upper-level waves. The initial conditions consist of upper -tropospheric disturbances that lean against the shear. They strongly excite upper-level waves not only in the absence of tropospheric potential vorticity gradients, but also in their presence. This result demonstrates that quasi -modes are as likely to emerge from favorably configured initial conditions as real normal modes, although their excitation is followed by a slow decay. (Copies available exclusively from MIT Libraries, Rm. 14-0551, Cambridge, MA 02139-4307. Ph. 617-253-5668; Fax 617-253-1690.).

  7. Counseling in Greece

    ERIC Educational Resources Information Center

    Malikiosi-Loizos, Maria; Ivey, Allen E.

    2012-01-01

    There is rapid growth in Greece's professional and research activity in counseling, despite the lack of a clear professional identity for the field. It is hoped this will be overcome through the newly started graduate programs. Opportunities, objectives, and strategies for counseling's advancement should be directed toward close and essential…

  8. Greece. [CME Country Reports].

    ERIC Educational Resources Information Center

    Council of Europe, Strasbourg (France). Documentation Center for Education in Europe.

    There is no immigration problems in Greece today. On the contrary, the country's economic development makes it necessary for Greek workers who have emigrated temporarily to return and be integrated into the production system. The educational policy for emigrant workers' children involves: (1) ensuring that children who have settled abroad know…

  9. Preparing Faculty in Greece

    ERIC Educational Resources Information Center

    Kioumourtzoglou, Efthimis

    2003-01-01

    The current article aimed to describe the process followed for faculty preparation and development in Greece. More specifically, it includes information regarding (a) the possibilities for professional development through Master and PhD programs, (b) the existing faculty categories, (c) the procedure followed by the departments in collaboration…

  10. Alternative Use in Greece.

    ERIC Educational Resources Information Center

    PEB Exchange, 1992

    1992-01-01

    Situating the University of Thessaly in Volos and Larissa, Greece, represents the idea that the university has a role to play in the community, and, therefore, its facilities are integrated within the city. Describes an old factory warehouse converted to create "a building within a building," while preserving style of the former factory in terms…

  11. Mesoscale and synoptic scale transport of aerosols

    SciTech Connect

    Wolff, G.T.

    1980-01-01

    An overview is presented of mesoscale and synoptic-scale (macroscale) aerosol transport as observed in recent air pollution field studies. Examples of mesoscale transport systems are discussed, including urban plumes, sea breezes, the mountain-valley wind cycle, and the urban-heat-island circulation. The synoptic-scale systems considered are migrating high- and low-pressure systems. Documented cases are reviewed of aerosol transport in the various mesoscale systems, aerosol accumulation and transport in high-pressure systems, and acid precipitation in low-pressure systems. The characteristics of the transported aerosols are identified, along with the chemical species that occur primarily in aerosols in the accumulation mode (particle diameters of 0.1-3 microns). It is shown that aerosol particles in the accumulation mode are the most important in terms of synoptic-scale and mesoscale transport and that such particles are primarily responsible for visible haze.

  12. Synoptic Observing at Big Bear Solar Observatory

    NASA Astrophysics Data System (ADS)

    Denker, C.; Naqvi, M.; Deng, N.; Tritschler, A.; Marquette, W. H.

    2007-05-01

    Synoptic solar observations in the chromospheric absorption lines Ca II K and Hα have a long tradition at Big Bear Solar Observatory (BBSO). The advent of the New Solar Telescope (NST) will shift the focus of BBSO's synoptic observing program toward high-resolution observations. We present an overview of the telescopes and instrumentation and show some of the most recent results. This includes Ca II K data to track solar irradiance variations, Hα full-disk data to monitor eruptive events, Dopplergrams from two-dimensional spectroscopy, as well as image restorations of diffraction-limited quality.

  13. Synoptic analysis of frost days in Zanjan Province of Iran

    NASA Astrophysics Data System (ADS)

    Alijani, B.; Tagiloo, M.

    2010-09-01

    As a general rule it is accepted that every change in the environment is controlled by the changes in the pressure patterns or varying synoptic systems. We are witnessing intensive floods, damaging cold waves, or highly polluted air every year, all of which are related to some extent to the pressure patterns such as intensive cyclones or subsiding anticyclones. The frost days are one of these environmental conditions that are caused by these pressure patterns especially in the case of synoptic frosts. The Zanjan province of Iran with mountainous nature and higher elevations is one of the frost prone regions in the country. Most of the years this region suffers from intensive and damaging frosts such as the one occurred in December 2006 and January 2007. In order to advise planners and users, and lower the damages of such frosts, this study tried to analyze the synoptic origin of the December 2006 frost. To achieve the objective of the study the frost days of the province during months December 2006 and January 2007 were selected. During these months all of the four stations of the Province ( Zanjan, Khorramdarreh, Khodabandeh, and Mahneshan) had experienced sub-zero temperatures. The daily zero GMT surface and 500 hPa. maps of the region were extracted from the National Center of Environmental Protection (NCEP) site for the selected days. The pressure patterns of both levels were analyzed and assigned into different groups. The results showed that the main synoptic patterns responsible for the frosts of the region are the Caspian trough, Siberian high pressure, moving western anticyclones, upper level blockings, and cut off lows. When the Caspian Sea trough deepens it brings the westerly anticyclones to the area. Under its eastward displacement, the Siberian High develops and sends its ridges towards the study region. Some times the upper level blocking of the Siberian area brings the cold air masses to the study region. In general, the development and displacement

  14. Synoptic Control of Cross-Barrier Precipitation Ratios

    NASA Astrophysics Data System (ADS)

    Mass, C.; Vargas, R.

    2013-12-01

    The substantial precipitation contrasts across mountain barriers, with windward enhancement on one side and leeward reduction on the other, have been the subject of several studies and reviews, both observational and theoretical. A lesser number of papers have examined the temporal variability of the orographic precipitation contrasts, including the origins of such variability. For example, Siler et al. (2013) examined the variability of the rain-shadow effect across the Cascade Mountains of Washington State. They found that the intensity of the winter-mean rain shadow was weaker in El Nino than La Nina years, and suggested that the strongest (weakest) rain shadows occurred for warm-sector (warm-frontal) situations. Dettinger et al. (2004) examined the synoptic controls of varying orographic precipitation ratios across the Sierra Nevada of California, with ratios defined by the difference in precipitation between the Central Valley and the western slopes of the barrier. They found increased ratios when the flow was more normal to the terrain and when vertical stability was less, with higher ratios after cold frontal passage compared to the warm sectors of midlatitude cyclones. The latter result appears to contradict the findings of Siler et al (2013). This presentation explores the temporal variations in the intensity of the precipitation gradient across the Cascade Mountains of Washington State and describes the synoptic conditions associated with periods in which precipitation is heavier on the western side, heavier on the eastern side, or nearly equal across the barrier. The talk will begin by summarizing the temporal variations of precipitation on the windward and leeward sides of the Cascades for a several year period. Segregating the hours when precipitation is substantially greater on the windward side, greater on the leeward side, or roughly equal, provides a series of dates used for synoptic composites for these three situations. It is shown that there are

  15. A Synoptic Framework for School Program Evaluation.

    ERIC Educational Resources Information Center

    Maher, Charles A.

    1978-01-01

    A broad-based conceptual scheme, termed the Synoptic Evaluation Framework (SEF), provides school program evaluation services. The SEF allows for the design and conduct of a range of program evaluation studies within the school context, and has been used as a basis for training doctoral school psychology students in program evaluation. (Author)

  16. HMI Vector and Uncertainty Carrington Synoptic Maps

    NASA Astrophysics Data System (ADS)

    Bertello, Luca; Hughes, A.; Gosain, Sanjay; Harker, Brian; Harvey, J. W.; Marble, Andrew R.; Pevtsov, Alexei A.

    2016-05-01

    Based on our experience with data from the Vector Spectromagnetograph (VSM) instrument, which is part of the Synoptic Optical Long-term Investigations of the Sun (SOLIS)facility, we have produced HMI vector and uncertainty synoptic maps for all Carrington rotations from May 2010 through December 2015. HMI observations provide 12-minute cadence magnetograms, both for longitudinal and full-Stokes measurements. For this investigation we have used only two magnetograms per day, 12 hours apart, which are sufficient to produce accurate maps in the longitude-sine(latitude) projection with 1x1 square-degree resolution at the equator. From both the HMI longitudinal and vector magnetograms we have computed radial-flux and spatial-variance synoptic maps. For the longitudinal data, we have included pole-filled radial-flux maps, and for the vector data, we have included synoptic maps of the poloidal and toroidal magnetic flux.We describe here the procedure to generate those maps and discuss some of their main features. A comparison with similar products from the SOLIS/VSM is also addressed. The HMI data used are courtesy of NASA/SDO and HMI science teams.

  17. Corinth Canal, Greece

    NASA Technical Reports Server (NTRS)

    2006-01-01

    The Isthmus of Corinth has played a very important role in the history of Greece. It is the only land bridge between the country's north (Attica) and south (Peloponnese). It is a 6 km wide tongue of land separating the Gulf of Corinth from the Saronic Sea. Populations, armies and commodities have got to move through it. In the 6th century BCE, the Greeks built the Diolkos, a 10 meter-wide stone roadway to pull ships across the Isthmus on wooden cylinders and wheeled vehicles. In 1882, a canal was started and completed 11 years later. It is 6343 meters long, 25 meters wide, and 8 meters deep.

    With its 14 spectral bands from the visible to the thermal infrared wavelength region, and its high spatial resolution of 15 to 90 meters (about 50 to 300 feet), ASTER images Earth to map and monitor the changing surface of our planet.

    ASTER is one of five Earth-observing instruments launched December 18, 1999, on NASA's Terra satellite. The instrument was built by Japan's Ministry of Economy, Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and the data products.

    The broad spectral coverage and high spectral resolution of ASTER provides scientists in numerous disciplines with critical information for surface mapping, and monitoring of dynamic conditions and temporal change. Example applications are: monitoring glacial advances and retreats; monitoring potentially active volcanoes; identifying crop stress; determining cloud morphology and physical properties; wetlands evaluation; thermal pollution monitoring; coral reef degradation; surface temperature mapping of soils and geology; and measuring surface heat balance.

    The U.S. science team is located at NASA's Jet Propulsion Laboratory, Pasadena, Calif. The Terra mission is part of NASA's Science Mission Directorate.

    Size: 25.3 by 37.7 kilometers (15.7 by 23.4 miles) Location: 37.9 degrees North latitude, 23 degrees East longitude

  18. Leishmaniases in Greece

    PubMed Central

    Ntais, Pantelis; Sifaki-Pistola, Dimitra; Christodoulou, Vasiliki; Messaritakis, Ippokratis; Pratlong, Francine; Poupalos, George; Antoniou, Maria

    2013-01-01

    During the last 35 years, visceral leishmaniasis has spread in Greece with autochthonous human cases appearing in 41 of the 54 prefectures. The occurrence of the disease was mapped and related to dog seropositivity, environmental and geospatial risk factors. Average dog seropositivity was 22.1% and positive animals were found in 43 of 54 prefectures. Factors like: altitude, presence of water bodies, land use, wind speed, mean land surface temperature, mean relative humidity, and mean annual rainfall were found to affect dog seropositivity. Cases of cutaneous leishmaniasis, caused by Leishmania tropica are also increasing. Phlebotomus similis believed to be the potential vector of L. tropica in Greece, was found in areas where the disease is widespread but also where cases have never been reported implying a danger of introduction of this anthroponotic parasite to new regions. PMID:24062479

  19. The zeolite deposits of Greece

    USGS Publications Warehouse

    Stamatakis, M.G.; Hall, A.; Hein, J.R.

    1996-01-01

    Zeolites are present in altered pyroclastic rocks at many localities in Greece, and large deposits of potential economic interest are present in three areas: (1) the Evros region of the province of Thrace in the north-eastern part of the Greek mainland; (2) the islands of Kimolos and Poliegos in the western Aegean; and (3) the island of Samos in the eastern Aegean Sea. The deposits in Thrace are of Eocene-Oligocene age and are rich in heulandite and/or clinoptilolite. Those of Kimolos and Poliegos are mainly Quaternary and are rich in mordenite. Those of Samos are Miocene, and are rich in clinoptilolite and/or analcime. The deposits in Thrace are believed to have formed in an open hydrological system by the action of meteoric water, and those of the western Aegean islands in a similar way but under conditions of high heat flow, whereas the deposits in Samos were formed in a saline-alkaline lake.

  20. Heavy Thunderstorm Synoptic Climatology and Forcing Mechanisms in Saudi Arabia.

    NASA Astrophysics Data System (ADS)

    Ghulam, Ayman S.

    2010-05-01

    Meteorologists are required to provide accurate and comprehensive weather information for planning and operational aviation, agricultural, water projects and also for the public. In general, weather phenomena such as thunderstorms over the area between the tropics and the middle latitudes are not fully understood, particularly in the Middle East area, for many reasons such as: 1) the complexity of the nature of the climate due to the wide-ranging diversity in the topography and landscape in the area; 2) the lack of meteorological data in the area; and 3) the lack of studies on local weather situations. In arid regions such as Saudi Arabia, the spatial and temporal variation of thunderstorms and associated rainfall are essential in determining their effects on social and economic conditions. Thunderstorms form rapidly, due to the fact that the significant heating of the air from the surface and the ensuing rainfall usually occurs within a short period of time. Thus, understanding thunderstorms and rainfall distribution in time and space would be useful for hydrologists, meteorologists and for environmental studies. Research all over the world has shown, however, that consideration of local factors like Low Level Jets (LLJ), moisture flux, sea breezes, and the Red Sea Convergence Zone (RSCZ) would be valuable in thunderstorm prediction. The combined effects of enhanced low-level moisture convergence and layer destabilization due to upslope flow over mountainous terrain has been shown to be responsible for thunderstorm development in otherwise non-favourable conditions. However, there might be other synoptic features associated with heavy thunderstorms or cause them, but these features have not been investigated in any research in Saudi Arabia. Thus, relating the local weather and synoptic situations with those over the middle latitudes will provide a valuable background for the forecasters to issue the medium-range forecasts which are important for many projects

  1. Carbonate-replacement Pb-Zn-Ag ± Au mineralization in the Kamariza area, Lavrion, Greece: Mineralogy and thermochemical conditions of formation

    NASA Astrophysics Data System (ADS)

    Voudouris, P.; Melfos, V.; Spry, P. G.; Bonsall, T. A.; Tarkian, M.; Solomos, Ch.

    2008-09-01

    Carbonate-replacement Pb-Zn-Ag ± Au deposits in the Kamariza area, Lavrion district, Attica, Greece, are genetically related to the emplacement of Miocene andesitic dikes within a rapidly extending continental back-arc basin, which formed during exhumation of the Attic-Cycladic Crystalline Belt. Replacement veins as well as chimneys and mantos of massive sulfides are the major orebody types with mantos grading into chimneys and veins. Ore minerals are similar among the various types of orebodies in the Kamariza area and consist of sulfides and sulfarsenides (pyrite, arsenopyrite, chalcopyrite, galena, sphalerite, gersdorffite, marcasite), native metals (Au and Bi), Sn-bearing phases (petrukite), sulfosalts and sulfbismuthites of Ag, Bi, Cu, Pb, As, Sb (tetrahedrite-group minerals, bournonite, boulangerite, stephanite, pyrargyrite, semseyite, enargite, bismuthinite, lillianite homologues, Cu-matildite, aikinite, Ag-aikinite, mummeite, emplectite, wittichenite). The elemental association of Bi, Au, and Ag is common. The assemblages gersdorffite-bismuthinite-native gold and native gold-native bismuth are evidence for a contribution of magmatic components to the hydrothermal system. A fluctuation in the sulfidation states of the ore fluid during the evolution of the Kamariza system is evident from the deposition of early arsenopyrite, as well as of enargite-luzonite and both low-Fe and Fe-rich sphalerite in the same samples. Microthermometry of fluid inclusion assemblages show that carbonate replacement mineralization was deposited from a warm to hot (100°C to 400°C), low to moderately saline (1.8 to 17.3 wt% NaCl equiv) fluid. Eutectic temperatures of fluid inclusions as low as -55°C suggest the presence of CaCl2 in addition to NaCl, in the ore fluid. The Kamariza deposit occurs distal to the Plaka granodiorite intrusion and the associated porphyry-Mo mineralization, but is likely to be genetically related to a granitoid buried at depth.

  2. An Upper-Air Synoptic Climatology of the Western United States.

    NASA Astrophysics Data System (ADS)

    Davis, Robert E.; Walker, David R.

    1992-12-01

    An automated, year-round synoptic climatology is developed for the western United States from rawinsonde observations from 1979 to 1988. The classification uses thermal, moisture, and flow parameters to characterize seasonal and interannual synoptic-scale variations in hydrodynamic and thermodynamic conditions. Based on twice daily observations for a network of 21 stations from the Pacific coast to the Rockies, a synoptic climatology is developed using air temperature, dewpoint temperature, geopotential height, and the east-west and north-south components of the wind vector at 800-, 700-, 500-, and 250-mb constant pressure surfaces. The 798 variable by 3620 day matrix is reduced to six orthogonal principal components, and the resulting component scores are grouped using a two-stage clustering technique. The 13 synoptic situations represent days experiencing homogeneous weather conditions. These synoptic situations exhibit marked seasonality and interannual variability and depict features observed in the general circulation of the atmosphere. Examples include both summer monsoonal and dry situations, zonal flow situations with a strong polar or subtropical jet, or both and strong ridging or troughing, and meridional flow.

  3. Lightning characteristics in Eastern Mediterranean thunderstorms during different synoptic systems

    NASA Astrophysics Data System (ADS)

    Ben Ami, Y.; Altaratz, O.; Yair, Y.; Koren, I.

    2015-06-01

    Thunderstorms activity takes place in the Eastern Mediterranean mainly along the boreal fall and winter seasons during synoptic systems of Red Sea Trough (RST), Red Sea Trough that closed a low over the sea (RST-CL), and Cyprus Low (during fall - FCL and Winter - WCL). In this work we used the Israeli Lightning Location System ground strokes dataset (between October 2004 and December 2010) for studying the lightning strokes properties and their link to the thermodynamic conditions in each synoptic system. It is shown that the lightning activity dominates over sea during WCL and FCL systems (with maximum values of 37 strokes per 25 km2 day-1 in WCL, and 54 in FCL) and have a dominant component over land during the RST and RST-CL days. The stronger instability (high CAPE values of 621 ± 466 J kg-1) during RST-CL days together with the higher altitude of the clouds' mixed-phase region (3630 ± 316 m) result in higher ground strokes density during this system (compared to all other) but lower fraction of positive ground strokes (3 ± 0.5%). In general the fraction of positive strokes was found to be positively correlated with the wind shear values in the layer between 0 and -25 °C. It increases from the 1.2 ± 1% in early fall to 17 ± 7% in late winter, (during FCL and WCL days) and can be linked to the decrease in the sea surface (and lower troposphere) temperature during those months, due to an impact on the charge centers vertical location. The diurnal cycle in the lightning activity was examined for each synoptic system. During WCL conditions no preferred times were found along the day (as it relates to the timing of frontal systems). During the fall systems (FCL and RST-CL) there is a peak in lightning activity during the morning hours, probably related to the enhanced convection driven by the convergence between the eastern land breeze and the western synoptic winds. The distributions of peak currents in FCL and WCL systems also change from fall to winter and

  4. Synoptic Patterns Associated with Northeast and Southeast Ice Storms

    NASA Astrophysics Data System (ADS)

    Vargas, R., Jr.; Booth, J. F.

    2014-12-01

    Wintertime storms that produce precipitation events such as snow, freezing rain, and ice pellets cause significant damage to utility services and disrupt travel. These synoptic systems involve deep isothermal regions where warm, moist air over-runs surface sub-freezing air. However, little else is known about the synoptic evolution of the storms. Therefore this study analyzes the dynamic and thermodynamic conditions of ice events along the east coast. The National Climatic Data Center (NCDC) Storm Events Database is used to pull the dates of ice events from the Northeast and Southeast climate regions for 1996-2013. We find that Southeast ice storms often cover a large geographical region, while Northeast ice storms tend to be much smaller but more frequent. We utilize Geographic Information Systems (GIS) to relate the spatial coverage of our ice events to population density in order to compare the impacts of the events in the two regions. Next, we analyze the synoptic control of ice storms from both regions in an effort to explain what causes the size differences. For the ice storms gathered from the Storm Events Database, composites are generated for sea level pressure, 2-meter temperatures, 850-hPa temperature and 850-500 hPa thickness, and vorticity parameters, from reanalysis data. A comparison of the composites for the Southeast and Northeast storms suggests that the size differences relate in part to the thermal structure produced by cold air damming. The ice events are also associated with objectively identified cyclone tracks, and we find that cyclone forward speed is inversely proportional to the size of the ice storm produced.

  5. The measurement of the synoptic scale wind over the ocean

    NASA Technical Reports Server (NTRS)

    Pierson, W. J.

    1982-01-01

    Mesoscale and microscale features of the turbulent winds over the ocean are related to the synoptic scale winds in terms of published spectral forms for the microscale, a mesoscale valley and published values of U*, VAR u', VAR v' and z/L, as defined in the text and as obtained for moderate to gale force winds. The frequencies involved correspond to periods longer than 1 hour and extend to the microscale, which starts at a period near 2 minutes, or so, and continues to the Kolmogorov inertial range. Nondimensional spectra that span both the mesoscale and the microscale are derived as a function of u, f(= n z/u) and z/L, where z is 10 meters, L is the Monin Obukov stability length and u is evaluated at 10 meters. For the same u, different values of z/L produce a range of values of u which in turn result in variations of the eddy structure of the mesoscale and microscale spectra. Both conventional anemometer averages and remotely sensed winds contain a random component of the mesoscale wind in their values. These components are differnces and not errors when winds are compared, and quantitative values for these differences are given. Ways to improve the measurement of the synoptic scale wind by transient ships, data buoys and scatterometers on future spacecraft are described. These ways are loner averaging times for ships and data buoys, depending on the synoptic conditions, and pooling spacecraft to form super observations. Design considerations for future remote sensing systems are given.

  6. The anomalous low and high temperatures of 2012 over Greece - an explanation from a meteorological and climatological perspective

    NASA Astrophysics Data System (ADS)

    Tolika, K.; Maheras, P.; Pytharoulis, I.; Anagnostopoulou, C.

    2014-03-01

    2012 was the hottest year in Greece on the basis of the available record dating back to 1958, displaying at the same time the widest annual temperature range. During the summer and autumn months, numerous regions in the domain of study experienced record-breaking maximum and minimum temperatures. Conversely, the winter period was particularly cold and January one of the coldest months over the last 55 yr. The analysis of the cold period indicates that the synoptic conditions resemble the positive phase of the Eastern Mediterranean Pattern (EMP). The predominance of these cool conditions seems to be related primarily to an intense NNW or NNE atmospheric circulation, as a consequence of the positive EMP phase. Moreover, the reduction in the floating sea ice emerges as a key driver of the formation of a low-pressure pattern and the reinforcement of the trough south of Scandinavia, which in turn strengthened the Siberia High east of the trough. This reinforcement resulted in a blocking pattern and in favorable conditions for the EMP formation. The atmospheric circulation during the prolonged high-temperature period resembles, respectively, the negative phase of North Sea-Caspian Pattern teleconnection. The observed positive pole, in conjunction with the strong southwestern circulation, results in temperature increases and in the development of a smooth pressure field that contributes to the weakening of the Etesian winds and therefore to calm conditions over the continental areas.

  7. Using a synoptic climatological approach to understand climate-viticulture relationships

    NASA Astrophysics Data System (ADS)

    Jones, Gregory V.; Davis, Robert E.

    2000-06-01

    Regional circulation and local air mass synoptic climatologies are developed for Bordeaux, France, to examine the relationship between climate and viticulture. Using a variation of the temporal synoptic index, days with similar weather (both throughout Western Europe and at Bordeaux) are grouped together. The annual relative frequencies of these groups are used as independent variables to investigate climate-viticulture relationships for the region. The viticulture data are divided annually into stages based on the region-wide mean phenology of the grapevines. Synoptic climate-phenology models are then developed using multiple linear regression analysis.A high degree of spatial and temporal cohesiveness is found between the regional and the local synoptic climatologies. Circulation patterns identified in the regional circulation analyses are linked in a consistent fashion with corresponding thermal, moisture, wind and cloud cover conditions at the Bordeaux site.A small number of synoptic clusters greatly affect viticultural potential throughout the year. In general, vintage quality and production are reduced by (i) increased frequencies of cold- and moisture-producing events that delay the plant's physiology, and (ii) increases in frontal incursions and the associated winds and rain that affect flowering and the setting of berries. Conversely, the relative occurrence of warm, stable events during maturation lead to full ripeness and higher vintage quality.

  8. Leptospirosis in Greece.

    PubMed

    Papa, Anna; Kotrotsiou, Tzimoula

    2015-09-01

    Leptospirosis is a zoonotic disease with increased public health concern worldwide. The disease occurs more often in temperate and tropical regions. The present study analyzes the demographic, epidemiological and clinical data of 168 leptospirosis cases laboratory diagnosed in northern Greece during 1998-2014. Most patients were males, aged 50-69 years, working in animal husbandry or farming. Cases were observed more frequently in summer and autumn. Severity of the disease was correlated with presence of pulmonary involvement and hemorrhagic manifestations. PMID:26026714

  9. Greece and Turkey

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Summer is in full swing in this stunning true-color image of the southeastern European countries and Turkey captured by MODIS on June 29, 2002. Clockwise from left, the mountains of Greece, Albania, Macedonia, Yugoslavia, Bulgaria, and Turkey are swathed in brilliant greens and shades of golden brown; meanwhile (counterclockwise from left) the Ionian, Mediterranean, Aegean, and Black Seas are beautifully blue and green.Running diagonally across the image from the bottom middle to the top right is a gray streak that is caused by the angle of reflection of the sun on the water (called sun glint). The darker areas within this gray swath denote calmer water, and make visible currents that would not otherwise be noticeable.Surprisingly few fires were burning hot enough to be detectable by MODIS when this image was acquired during the height of the summer dry season. A single fire is visible burning in mainland Greece, six are visible in northwestern Turkey, and one burns on the western coast (marked with red outlines). Credit: Jacques Descloitres, MODIS Land Rapid Response Team, NASA/GSFC

  10. Estimated synoptic distributions of SABER data

    NASA Astrophysics Data System (ADS)

    Lingenfelser, G.; Remsberg, E.; Harvey, V.; Grose, W.

    2003-04-01

    The Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) instrument aboard the TIMED (Thermosphere, Ionosphere, Mesosphere Energetics and Dynamics) satellite has been obtaining measurements since January 2002. The Version 1.01 Level 2A LTE temperature data have been compared with temperature data obtained by other satellites, lidars, and falling spheres. The agreement between the SABER temperature profiles and those for other data sets indicate that the Version 1.01 SABER LTE temperature versus pressure distributions are suitable to use in dynamical studies of the middle atmosphere through the calculation of winds and potential vorticity. A first step in the calculation of dynamical parameters is to use a sequential estimation technique to obtain synoptic temperature distributions from the asynoptic SABER satellite data. The algorithm that was used in the LIMS data mapping has been updated and applied to the SABER temperature data to generate Fourier coefficients which are output at noon UT for each day as a function of latitude. From these spectral coefficients, synoptic temperature fields are estimated. The estimated data will be compared with assimilated fields in an attempt to further assess the quality of the SABER data.

  11. The variable sky of deep synoptic surveys

    SciTech Connect

    Ridgway, Stephen T.; Matheson, Thomas; Mighell, Kenneth J.; Olsen, Knut A.; Howell, Steve B.

    2014-11-20

    The discovery of variable and transient sources is an essential product of synoptic surveys. The alert stream will require filtering for personalized criteria—a process managed by a functionality commonly described as a Broker. In order to understand quantitatively the magnitude of the alert generation and Broker tasks, we have undertaken an analysis of the most numerous types of variable targets in the sky—Galactic stars, quasi-stellar objects (QSOs), active galactic nuclei (AGNs), and asteroids. It is found that the Large Synoptic Survey Telescope (LSST) will be capable of discovering ∼10{sup 5} high latitude (|b| > 20°) variable stars per night at the beginning of the survey. (The corresponding number for |b| < 20° is orders of magnitude larger, but subject to caveats concerning extinction and crowding.) However, the number of new discoveries may well drop below 100 per night within less than one year. The same analysis applied to GAIA clarifies the complementarity of the GAIA and LSST surveys. Discovery of AGNs and QSOs are each predicted to begin at ∼3000 per night and decrease by 50 times over four years. Supernovae are expected at ∼1100 per night, and after several survey years will dominate the new variable discovery rate. LSST asteroid discoveries will start at >10{sup 5} per night, and if orbital determination has a 50% success rate per epoch, they will drop below 1000 per night within two years.

  12. Synoptic-Scale Behavior of the Extratropical Tropopause Inversion Layer

    NASA Astrophysics Data System (ADS)

    Pilch Kedzierski, Robin; Matthes, Katja; Bumke, Karl

    2015-04-01

    The Tropopause Inversion Layer (TIL) is a climatological feature of the tropopause region, characterized by enhanced static stability and strong temperature inversion in a thin layer (about 1km deep) right above the tropopause. It was discovered recently via tropopause-based averaging [Birner 2002]. The sharp static stability, temperature and wind shear gradients of the TIL theoretically shall inhibit stratosphere-troposphere exchange and influence the vertical propagation of planetary scale Rossby and small-scale gravity waves. High vertically resolved radiosonde and GPS radio occultation measurements show that the strength of the TIL is positively correlated with the tropopause height and anticyclonic conditions, and that it reaches its maximum strength in polar regions during summer [Birner 2006] [Randel and Wu, 2007 and 2010]. Our study takes advantage of the high density of vertical profiles (~2000 measurements per day, globally) measured by the COSMIC satellites (2007-present), in order to describe the synoptic-scale structures of the TIL and the differences between the seasonal climatologies from earlier studies and the real-time TIL. Also, using ERA-Interim reanalysis wind fields, we split relative vorticity into shear and curl terms and study separately their relation to TIL strength in cyclonic-anticyclonic conditions. We find that the TIL has a rich zonal structure, especially in midlatitude winter, and that its strength is instantly adjusted to the synoptic situation at near-tropopause level. The peaks of strongest TIL at midlatitude ridges in winter are stronger and much more frequent than any peaks found in polar summer. The roles of shear and curl vorticity differ substantially towards higher values of relative vorticity (both cyclonic and anticyclonic).

  13. Pleural calcification in northwest Greece

    SciTech Connect

    Bazas, T.; Oakes, D.; Gilson, J.C.; Bazas, B.; McDonald, J.C.

    1985-12-01

    Mass miniature radiography in 1969 detected a high prevalence of pleural calcification in three villages in northwest Greece. In 1980 a survey of a 15% sample of the population over the age of 10 was carried out with a 80% response rate. Full-size radiographs, ventilatory capacity measurements, and a detailed questionnaire on respiratory symptoms, type of work, and residence were used. Independent classification of the 408 films by two readers using the ILO/UC scheme showed very few small opacities but a very high prevalence of pleural calcification first evident in young adults and rising to 70% in the elderly. The overall prevalence was 34.7% in men and 21.5% in women. A comparison with the 1969 survey showed a progression rate of 5% per annum. In neither sex was there a significant relation of pleural calcification to smoking, ventilatory capacity, nor type of work, though those classified as field croppers had a slightly higher prevalence. There was no obvious evidence of increased lung cancer or mesothelioma in the village. The agent responsible for this apparently benign condition was not identified.

  14. A Communities of Practice Approach to the Synoptic Problem

    ERIC Educational Resources Information Center

    Madrigal, Ramon Anthony

    2012-01-01

    Although the study of the Synoptic Problem has been the focus of scholarly attention for over two hundred years, the social learning theory known as Communities of Practice is a relatively recent phenomenon. This article describes a communities of practice approach to the study of the Synoptic Problem in an upper-division undergraduate course at a…

  15. An Automated Solar Synoptic Analysis Software System

    NASA Astrophysics Data System (ADS)

    Hong, S.; Lee, S.; Oh, S.; Kim, J.; Lee, J.; Kim, Y.; Lee, J.; Moon, Y.; Lee, D.

    2012-12-01

    We have developed an automated software system of identifying solar active regions, filament channels, and coronal holes, those are three major solar sources causing the space weather. Space weather forecasters of NOAA Space Weather Prediction Center produce the solar synoptic drawings as a daily basis to predict solar activities, i.e., solar flares, filament eruptions, high speed solar wind streams, and co-rotating interaction regions as well as their possible effects to the Earth. As an attempt to emulate this process with a fully automated and consistent way, we developed a software system named ASSA(Automated Solar Synoptic Analysis). When identifying solar active regions, ASSA uses high-resolution SDO HMI intensitygram and magnetogram as inputs and providing McIntosh classification and Mt. Wilson magnetic classification of each active region by applying appropriate image processing techniques such as thresholding, morphology extraction, and region growing. At the same time, it also extracts morphological and physical properties of active regions in a quantitative way for the short-term prediction of flares and CMEs. When identifying filament channels and coronal holes, images of global H-alpha network and SDO AIA 193 are used for morphological identification and also SDO HMI magnetograms for quantitative verification. The output results of ASSA are routinely checked and validated against NOAA's daily SRS(Solar Region Summary) and UCOHO(URSIgram code for coronal hole information). A couple of preliminary scientific results are to be presented using available output results. ASSA will be deployed at the Korean Space Weather Center and serve its customers in an operational status by the end of 2012.

  16. High altitude bird migration at temperate latitudes: a synoptic perspective on wind assistance.

    PubMed

    Dokter, Adriaan M; Shamoun-Baranes, Judy; Kemp, Michael U; Tijm, Sander; Holleman, Iwan

    2013-01-01

    At temperate latitudes the synoptic patterns of bird migration are strongly structured by the presence of cyclones and anticyclones, both in the horizontal and altitudinal dimensions. In certain synoptic conditions, birds may efficiently cross regions with opposing surface wind by choosing a higher flight altitude with more favourable wind. We observed migratory passerines at mid-latitudes that selected high altitude wind optima on particular nights, leading to the formation of structured migration layers at varying altitude up to 3 km. Using long-term vertical profiling of bird migration by C-band Doppler radar in the Netherlands, we find that such migration layers occur nearly exclusively during spring migration in the presence of a high-pressure system. A conceptual analytic framework providing insight into the synoptic patterns of wind assistance for migrants that includes the altitudinal dimension has so far been lacking. We present a simple model for a baroclinic atmosphere that relates vertical profiles of wind assistance to the pressure and temperature patterns occurring at temperate latitudes. We show how the magnitude and direction of the large scale horizontal temperature gradient affects the relative gain in wind assistance that migrants obtain through ascending. Temperature gradients typical for northerly high-pressure systems in spring are shown to cause high altitude wind optima in the easterly sectors of anticyclones, thereby explaining the frequent observations of high altitude migration in these synoptic conditions. Given the recurring synoptic arrangements of pressure systems across temperate continents, the opportunities for exploiting high altitude wind will differ between flyways, for example between easterly and westerly oceanic coasts. PMID:23300969

  17. High Altitude Bird Migration at Temperate Latitudes: A Synoptic Perspective on Wind Assistance

    PubMed Central

    Dokter, Adriaan M.; Shamoun-Baranes, Judy; Kemp, Michael U.; Tijm, Sander; Holleman, Iwan

    2013-01-01

    At temperate latitudes the synoptic patterns of bird migration are strongly structured by the presence of cyclones and anticyclones, both in the horizontal and altitudinal dimensions. In certain synoptic conditions, birds may efficiently cross regions with opposing surface wind by choosing a higher flight altitude with more favourable wind. We observed migratory passerines at mid-latitudes that selected high altitude wind optima on particular nights, leading to the formation of structured migration layers at varying altitude up to 3 km. Using long-term vertical profiling of bird migration by C-band Doppler radar in the Netherlands, we find that such migration layers occur nearly exclusively during spring migration in the presence of a high-pressure system. A conceptual analytic framework providing insight into the synoptic patterns of wind assistance for migrants that includes the altitudinal dimension has so far been lacking. We present a simple model for a baroclinic atmosphere that relates vertical profiles of wind assistance to the pressure and temperature patterns occurring at temperate latitudes. We show how the magnitude and direction of the large scale horizontal temperature gradient affects the relative gain in wind assistance that migrants obtain through ascending. Temperature gradients typical for northerly high-pressure systems in spring are shown to cause high altitude wind optima in the easterly sectors of anticyclones, thereby explaining the frequent observations of high altitude migration in these synoptic conditions. Given the recurring synoptic arrangements of pressure systems across temperate continents, the opportunities for exploiting high altitude wind will differ between flyways, for example between easterly and westerly oceanic coasts. PMID:23300969

  18. Distribution of Culicoides in Greece.

    PubMed

    Patakakis, Michael J; Papazahariadou, Margarita; Wilson, Anthony; Mellor, Philip S; Frydas, Stavros; Papadopoulos, Orestis

    2009-12-01

    Culicoides biting midges (Diptera: Ceratopogonidae) were trapped between 1999 and 2004 at 122 locations in mainland Greece and on most of the larger Aegean and Ionian islands, using OVI light traps, in order to determine the distribution and seasonal activity of bluetongue virus vectors and other Culicoides species. Thirty-nine Culicoides species were identified, six of which (C. furcillatus, C. impunctatus, C. paolae, C. pictipennis, C. riethi, and C. scoticus) were identified for the first time in Greece. Two of these (C. impunctatus and C. scoticus) may be of veterinary importance due to their role as vectors of bluetongue virus and related orbiviruses. In addition, C. imicola was detected for the first time in mainland Greece. PMID:20836829

  19. The Need for Synoptic Solar Observations from the Ground

    NASA Astrophysics Data System (ADS)

    Pevtsov, A. A.

    2016-04-01

    Synoptic observations are indispensable in studies of long-term effects pertinent to variation in solar radiative output, space weather and space climate, as well as for understanding the physics of global processes taking place on our nearest star. Synoptic data also allow putting the Sun in the context of stellar evolution. Historically, the main-stay of such observations has been groundbased although the improving longevity of space-borne instruments puts some space missions into the category of synoptic facilities. Space- and groundbased (synoptic) observations are complementary to each other; neither is inferior or superior to the other. Groundbased facilities can have a long-term (50 years+) operations horizon, and in comparison with their spacebased counterparts, they are less expensive to operate and have fewer restrictions on international collaboration and data access. The instruments can be serviced, upgraded, and cross-calibrated to ensure the continuity and uniformity of long-term data series. New measurements could be added in response to changes in understanding the solar phenomena. Some drawbacks such as day-night cycle and the variable atmospheric seeing can be mitigated e.g., by creating global networks and by employing adaptive optics. Furthermore, the groundbased synoptic observations can serve as a backbone and a back-up to spacebased observations. Here I review some existing groundbased synoptic facilities, describe plans for future networks, and outline the current efforts in strengthening the international collaboration in synoptic solar observations from the ground.

  20. Synoptic conditions during wintertime temperature extremes in Alaska

    NASA Astrophysics Data System (ADS)

    Cassano, John J.; Cassano, Elizabeth N.; Seefeldt, Mark W.; Gutowski, William J.; Glisan, Justin M.

    2016-04-01

    The large-scale atmospheric state associated with widespread wintertime warm and cold extremes in southern Alaska was identified using 1989 to 2007 European Centre for Medium-Range Weather Forecasts Interim Re-Analysis (ERA-I) data. Extremes were defined as days with the coldest and warmest 1% of daily temperatures. Widespread extreme events were identified for days when at least 25 50 km grid cells in the study domain met the extreme temperature criteria. A total of 55 cold and 74 warm extreme days were identified in 19 winters. Composites of the atmospheric state from 5 days before through the day of the extreme events were analyzed to assess the large-scale atmospheric state associated with the extremes. The method of self-organizing maps (SOMs) was used to identify the range of sea level pressure (SLP) patterns present in the ERA-I December-February data, and these SLP patterns were then used to stratify the extreme days by their large-scale atmospheric circulation. Composites for all warm or cold extreme days showed less intense features than those for specific SLP patterns. In all of the composites temperature advection, strongest at 700 hPa, and anomalous longwave radiation were the primary factors that led to the extreme events. The anomalous downwelling longwave radiation was due to either reduced cloud cover, during cold extremes, or to increased cloud cover, during warm extremes. The SOM composites provided additional insight into the temporal evolution of the extreme days and highlighted different portions of southern Alaska most likely to experience temperature extremes for a given SOM SLP pattern.

  1. The Synoptic View as a Model for Poster Presentations

    NASA Astrophysics Data System (ADS)

    Rhodes, D. D.; Arrowsmith, J. R.

    2004-12-01

    Originally referencing the first three chapters of the New Testament, the term "synoptic" has come to mean "a general view of the whole, or of the principal parts of a thing." Large format posters provide an opportunity to present research in synoptic form, rather than as an arrangement of PowerPoint slides and text. In synoptic views, data, analyses, and linkages are presented en masse with the graphical design used as a guide to the linkages. Conclusions about the meanings of the information are largely left to the viewers as they study the information and seek relationships-a natural activity for scientists. Numerous formats produce synoptic views of geoscientific information. Each imposes order on the information through spatial, temporal, or causal connections and provide context for multiple variables. Maps are the most common synoptic presentations. Additional map-sheet information, such as stratigraphic columns and cross sections, gain meaning from and contribute meaning to the areal view. Two and three-dimensional models, including flow charts and organizational diagrams offer a means of portraying complex interactions. Time lines and spatial line (e.g., latitude, depth, distance) diagrams, especially those with additional axes to plot related variables, show temporal or spatial trends, progress, or fluctuation. Some organizational schemes are specific to the sciences. The periodic table is a synoptic portrayal of the elements that designates their chemical behavior by their positions. As an illustration of phenomena, the well designed synoptic poster provides a multi-scale perspective that slices across time, space, or other parameters to expose the significant behaviors of the given system. Bruce Railsback's (2003) reorganization of the periodic table to emphasize the charged species most common in geologic processes is an outstanding example of synoptic design. Edward Tufte's works on graphical style and visual explanations are also excellent guides to

  2. Synoptic meteorology and transport during the North Atlantic Regional Experiment (NARE) intensive: Overview

    NASA Astrophysics Data System (ADS)

    Merrill, John T.; Moody, Jennie L.

    1996-12-01

    Analyses of meteorological conditions during the North Atlantic Regional Experiment (NARE) intensive period, defined here as August 1 through September 13, 1993, indicate that transport in the study region in Nova Scotia was influenced by several well-defined synoptic disturbances (weak frontal passages or troughs) and by intervening periods of slowly varying transport conditions. Using trajectory analysis, synoptic charts, and other meteorological products, we have characterized these conditions and indicated the transitions in transport in relation to the synoptic scale meteorological situation. The ideal meteorological scenario for delivering pollution plumes from the U.S. East Coast urban areas over the Gulf of Maine to the Maritime Provinces of Canada is shown to be warm sector flow ahead of an advancing cold front. In addition, for two of these frontal passages we have discussed some of the smaller-scale effects which appear to have influenced the transport and or the composition of air masses reaching the NARE intensive region. Finally, we compare the conditions actually encountered during the field campaign with our idealized conceptual model of warm sector transport.

  3. High-frequency sea level oscillations in the Mediterranean and their connection to synoptic patterns

    NASA Astrophysics Data System (ADS)

    Šepić, Jadranka; Vilibić, Ivica; Lafon, Amaury; Macheboeuf, Loïc; Ivanović, Zvonko

    2015-09-01

    This paper contains a basin-wide assessment of high-frequency sea level oscillations in the Mediterranean Sea for the period from 2010 to 2014. Sea level series with temporal resolutions of 1 min were taken from 29 tide gauges that had been operational for at least 4 years with high-quality time series. The contribution of high-frequency sea level variance (2 min-6 h) to the total and residual sea level variance was estimated to vary between 0.4% and 9.5% and between 0.6% and 12.1%, respectively, but to become dominant at some stations during extreme high-frequency events. A total of 36 high-frequency sea level events were extracted from the series, with some occurring locally in one of the four selected regions of Spain, Sardinia, Sicily and the Greece-Ionian Sea (6 events), some occurring over two or three regions (19 events), and some occurring in all of the selected regions within a period of 1-3 days (11 events). The basin-wide events normally propagate from the western to the eastern parts of the basin, with an average velocity of approximately 30 km/h. Synoptic patterns associated with high-frequency events were analysed, and a high resemblance to patterns associated with meteotsunamis was observed: (i) a cyclone with a centre W-NW from the affected area, (ii) a strong thermal front in the lower troposphere, and (iii) a forefront of an unstable strong mid-tropospheric jet placed over the affected area. The strong coherence between high-frequency sea level events and synoptic patterns introduces the possibility of a timely forecast of these events.

  4. The influence of synoptic weather regimes on UK air quality: regional model studies of tropospheric column NO2

    NASA Astrophysics Data System (ADS)

    Pope, R. J.; Savage, N. H.; Chipperfield, M. P.; Ordóñez, C.; Neal, L. S.

    2015-10-01

    Synoptic meteorology can have a significant influence on UK air quality. Cyclonic conditions lead to the dispersion of air pollutants away from source regions, while anticyclonic conditions lead to their accumulation over source regions. Meteorology also modifies atmospheric chemistry processes such as photolysis and wet deposition. Previous studies have shown a relationship between observed satellite tropospheric column NO2 and synoptic meteorology in different seasons. Here, we test whether the UK Met Office Air Quality in the Unified Model (AQUM) can reproduce these observations and then use the model to explore the relative importance of various factors. We show that AQUM successfully captures the observed relationships when sampled under the Lamb weather types, an objective classification of midday UK circulation patterns. By using a range of idealized NOx-like tracers with different e-folding lifetimes, we show that under different synoptic regimes the NO2 lifetime in AQUM is approximately 6 h in summer and 12 h in winter. The longer lifetime can explain why synoptic spatial tropospheric column NO2 variations are more significant in winter compared to summer, due to less NO2 photochemical loss. We also show that cyclonic conditions have more seasonality in tropospheric column NO2 than anticyclonic conditions as they result in more extreme spatial departures from the wintertime seasonal average. Within a season (summer or winter) under different synoptic regimes, a large proportion of the spatial pattern in the UK tropospheric column NO2 field can be explained by the idealized model tracers, showing that transport is an important factor in governing the variability of UK air quality on seasonal synoptic timescales.

  5. Street Children in Contemporary Greece

    ERIC Educational Resources Information Center

    Altanis, Panagiotis; Goddard, Jim

    2004-01-01

    This article gives an overview of the problem of street children in Greece, within the context of global research on street children. The article draws on preliminary findings from recent research on street children in the urban centre of Athens. This is an under-researched area, with weak policy responses to a problem associated with recent…

  6. School Building Organisation in Greece.

    ERIC Educational Resources Information Center

    PEB Exchange, 2001

    2001-01-01

    Discusses the past and current organizational structure of Greece's School Building Organisation, a body established to work with government agencies in the design and construction of new buildings and the provisioning of educational equipment. Future planning to incorporate culture and creativity, sports, and laboratory learning in modern school…

  7. Synoptic and meteorological drivers of extreme ozone concentrations over Europe

    NASA Astrophysics Data System (ADS)

    Otero, N.; Sillmann, J.; Schnell, J. L.; Rust, H. W.; Butler, T.

    2016-02-01

    The present work assesses the relationship between local and synoptic meteorological conditions and surface ozone concentration over Europe in spring and summer months, during the period 1998-2012 using a new interpolated data set of observed surface ozone concentrations over the European domain. Along with local meteorological conditions, the influence of large-scale atmospheric circulation on surface ozone is addressed through a set of airflow indices computed with a novel implementation of a grid-by-grid weather type classification across Europe. Drivers of surface ozone over the full distribution of maximum daily 8 h average values are investigated, along with drivers of the extreme high percentiles and exceedances or air quality guideline thresholds. Three different regression techniques are applied: multiple linear regression to assess the drivers of maximum daily ozone, logistic regression to assess the probability of threshold exceedances and quantile regression to estimate the meteorological influence on extreme values, as represented by the 95th percentile. The relative importance of the input parameters (predictors) is assessed by a backward stepwise regression procedure that allows the identification of the most important predictors in each model. Spatial patterns of model performance exhibit distinct variations between regions. The inclusion of the ozone persistence is particularly relevant over southern Europe. In general, the best model performance is found over central Europe, where the maximum temperature plays an important role as a driver of maximum daily ozone as well as its extreme values, especially during warmer months.

  8. Synoptic and meteorological drivers of extreme ozone concentrations over Europe

    NASA Astrophysics Data System (ADS)

    Otero, Noelia Felipe; Sillmann, Jana; Schnell, Jordan L.; Rust, Henning W.; Butler, Tim

    2016-04-01

    The present work assesses the relationship between local and synoptic meteorological conditions and surface ozone concentration over Europe in spring and summer months, during the period 1998-2012 using a new interpolated data set of observed surface ozone concentrations over the European domain. Along with local meteorological conditions, the influence of large-scale atmospheric circulation on surface ozone is addressed through a set of airflow indices computed with a novel implementation of a grid-by-grid weather type classification across Europe. Drivers of surface ozone over the full distribution of maximum daily 8-hour average values are investigated, along with drivers of the extreme high percentiles and exceedances or air quality guideline thresholds. Three different regression techniques are applied: multiple linear regression to assess the drivers of maximum daily ozone, logistic regression to assess the probability of threshold exceedances and quantile regression to estimate the meteorological influence on extreme values, as represented by the 95th percentile. The relative importance of the input parameters (predictors) is assessed by a backward stepwise regression procedure that allows the identification of the most important predictors in each model. Spatial patterns of model performance exhibit distinct variations between regions. The inclusion of the ozone persistence is particularly relevant over Southern Europe. In general, the best model performance is found over Central Europe, where the maximum temperature plays an important role as a driver of maximum daily ozone as well as its extreme values, especially during warmer months.

  9. Description of wind field dynamic patterns in a valley and their relation to mesoscale and synoptic-scale meterological situations

    SciTech Connect

    Guardans, R.; Palomino, I.

    1995-01-01

    A large set of hourly meterological data from seven towers deployed in Montesina Valley (Cordoba, Spain) is studied in relation to the prevailing synoptic situation. The complete collection of daily synoptic maps for 1985-90 has been classified in seven basic weather patterns. First-order transition probabilities and weather pattern persistences have been calculated for each of the patterns. The behavior of the local valley wind field is described as a function of the synoptic patterns. The work reported here, based on observations of the characteristic time and space patterns of flow in the valley under different synoptic conditions, has made it possible to obtain a set of empirical rules and regression functions to produce forecasts of the local wind field as a function of the synoptic situation and the hour of the day to be used in the emergency plans. The result of this work is currently being implemented in an atmospheric dispersion module of an expert system that will be used as a tool to predict the evolution of accidental and routine hazardous emissions to the atmosphere in complex terrain such as valleys and coastal areas.

  10. An assessment of waterspout occurrence in the Eastern Adriatic basin in 2010: Synoptic and mesoscale environment and forecasting method

    NASA Astrophysics Data System (ADS)

    Renko, Tanja; Kozarić, Tomislav; Tudor, Martina

    2013-04-01

    In this paper we performed a comprehensive analysis of 19 waterspout events that occurred in the Eastern Adriatic basin in 2010. Data were collected from the synoptic and climatological weather stations and from eyewitness reports from newspapers and the internet. The geographical and temporal distributions of the waterspouts, as well as the absolute frequencies of four synoptic types relevant to waterspout development (south-west flow (SW), long-wave trough (LW), closed low (CLOSED) and short-wave trough (SWT), are presented. The synoptic and mesoscale weather conditions were analyzed using the ERA-Interim reanalysis data, satellite images, data from synoptic and automatic weather stations and atmospheric soundings. To test waterspouts for thunderstorm relations the LINET network sensor data were used to infer lightning activity. Because thermodynamic instability indices are usually insufficient for forecasting waterspout activity, the performance of the Szilagyi Waterspout Nomogram (SWN) and the Szilagyi Waterspout Index (SWI) were tested using the ALADIN model. The results of the analyses of the 2010 cases show that the SWN successfully forecasted 15 out of 19 events (hit rate of 78.9%). This is a significant hit rate but is not as high as in the work of Keul et al. (2009), in which 96% of the Adriatic cases satisfied the nomogram. In addition, four selected waterspout cases, which represent the four basic synoptic types, were analyzed in detail to provide an overview of favorable atmospheric environments for waterspouts throughout the year.

  11. Synoptic typing: interdisciplinary application methods with three practical hydroclimatological examples

    NASA Astrophysics Data System (ADS)

    Siegert, C. M.; Leathers, D. J.; Levia, D. F.

    2016-01-01

    Synoptic classification is a methodology that represents diverse atmospheric variables and allows researchers to relate large-scale atmospheric circulation patterns to regional- and small-scale terrestrial processes. Synoptic classification has often been applied to questions concerning the surface environment. However, full applicability has been under-utilized to date, especially in disciplines such as hydroclimatology, which are intimately linked to atmospheric inputs. This paper aims to (1) outline the development of a daily synoptic calendar for the Mid-Atlantic (USA), (2) define seasonal synoptic patterns occurring in the region, and (3) provide hydroclimatological examples whereby the cascading response of precipitation characteristics, soil moisture, and streamflow are explained by synoptic classification. Together, achievement of these objectives serves as a guide for development and use of a synoptic calendar for hydroclimatological studies. In total 22 unique synoptic types were identified, derived from a combination of 12 types occurring in the winter (DJF), 13 in spring (MAM), 9 in summer (JJA), and 11 in autumn (SON). This includes six low pressure systems, four high pressure systems, one cold front, three north/northwest flow regimes, three south/southwest flow regimes, and five weakly defined regimes. Pairwise comparisons indicated that 84.3 % had significantly different rainfall magnitudes, 86.4 % had different rainfall durations, and 84.7 % had different rainfall intensities. The largest precipitation-producing classifications were not restricted to low pressure systems, but rather to patterns with access to moisture sources from the Atlantic Ocean and easterly (on-shore) winds, which transport moisture inland. These same classifications resulted in comparable rates of soil moisture recharge and streamflow discharge, illustrating the applicability of synoptic classification for a range of hydroclimatological research objectives.

  12. The influence of synoptic weather regimes on UK air quality: regional model studies of tropospheric column NO2

    NASA Astrophysics Data System (ADS)

    Pope, R. J.; Savage, N. H.; Chipperfield, M. P.; Ordóñez, C.; Neal, L. S.

    2015-07-01

    Synoptic meteorology can have a significant influence on UK air quality. Cyclonic (anticyclonic) conditions lead to the dispersion (accumulation) of air pollutants away from (over) source regions. Meteorology also modifies atmospheric chemistry processes such as photolysis and wet deposition. Previous studies have shown a relationship between observed satellite tropospheric column NO2 and synoptic meteorology in different seasons. Here, we test whether the UK Met Office Air Quality in the Unified Model (AQUM) can reproduce these observations and then use the model to determine the controlling factors. We show that AQUM successfully captures the observed relationships, when sampled under the Lamb Weather Types, an objective classification of midday UK circulation patterns. By using a range of idealised NOx-like tracers with different e-folding lifetimes, we show that under different synoptic regimes the NO2 lifetime in AQUM is approximately 6 h in summer and 12 h in winter. The longer lifetime can explain why synoptic spatial column NO2 variations are more significant in winter compared to summer, due to less NO2 photochemical loss. We also show that cyclonic conditions have more seasonality in column NO2 than anticyclonic conditions as they result in more extreme spatial departures from the wintertime seasonal average. Within a season (summer or winter) under different synoptic regimes, a large proportion of the spatial pattern in the UK column NO2 field can be explained by the idealised model tracers, showing that transport is an important factor in governing the variability of UK air quality on seasonal synoptic timescales.

  13. Synoptic messages to extend climate data records

    NASA Astrophysics Data System (ADS)

    den Besselaar, E. J. M.; Klein Tank, A. M. G.; Schrier, G.; Jones, P. D.

    2012-04-01

    Synoptic messages (SYNOP) exchanged internationally for operational weather forecasting are regularly used to extend validated (quality controlled) daily climate time series to the present day, despite differences in measuring intervals and lack of validation. Here we focus on the effect of this on derived climate indices of extremes in Europe. Validated time series are taken from the European Climate Assessment & Dataset (ECA&D). Validated data and SYNOP over the period 01 April 1982 to 31 December 2004 are compared. The distribution of the difference series of validated data and SYNOP is skewed. Generally, minimum temperatures are lower or equal in the validated series, while maximum temperatures are higher or equal. This is at least partly due to the 24-hour (validated data) versus 12-hour (SYNOP) measuring intervals. The precipitation results are dependent on the difference between the measuring intervals of both time series. Time series of indices of extremes exhibit a non-climatic inhomogeneity for several indices when SYNOP are used to extend the validated series, leading to spurious trends. The sizes of the trends in pure validated and pure SYNOP series are generally in good agreement, but the absolute values of the indices show an offset. Accepting a trend error of 10%, the averaged winter minimum and maximum temperature and the number of tropical nights (minimum temperature >20°C) in summer allow only a very small fraction of SYNOP in the extended series (about 5-10%), while for the other indices studied here a larger fraction can be used (up to 50%).

  14. Sunsat-2004 satellite and synoptic VLF payload

    NASA Astrophysics Data System (ADS)

    Milne, Gw; Hughes, A.; Mostert, S.; Steyn, Wh

    Sunsat 2004 is a second satellite from the University of Stellenbosch, with intended suns-synchronous launch in late 2005. The first satellite, Sunsat, was launched in February 1999, and was Africa's first satellite The three-axis stabilised bus will normally point its main solar panel at the sun, but will rotate for imaging. The attitude determination and control system will use coarse sun sensors, magnetometers, rate gyros, and a star mapper, and use reaction wheels and torquer rods for actuation. The payloads include a multispectral pushbroom imager with less than 5m GSD, TV cameras, an Amateur Radio communications payload, and science experiments. The main South African science experiment is a VLF receiver. In the magnetosphere VLF waves play an important role in energy exchange processes with energetic particles. The wave-particle interactions can lead to particle precipitation into the atmosphere or introduce additional energy into particle populations in the magnetosphere. The former is important due to its effect on terrestrial communications while the latter is of interest, as it affects the environment in which satellites operate. A full understanding, of the magnetosphere and phenomena such as the aurora, airglow and particle precipitation, depends on comprehensive wave and particle models together with models of the background plasma density The energetic particle populations and background plasma densities have been extensively modelled using data from a large number of satellite, rocket and ground-based experiments but no comprehensive model of the wave environment exist. The proposed synoptic VLF experiment will start to address this need by locating and tracking the morphology of regions in the magnetosphere where waves are generated. The experiment would consist of a nine channel VLF receiver with a loop antenna. The data would be recorded on board and transmitted to ground stations at appropriate times. A number of additional science payloads are

  15. Synoptic maps constructed from brightness observations of Thomson scattering by heliospheric electrons

    NASA Technical Reports Server (NTRS)

    Hick, P.; Jackson, B.; Schwenn, R.

    1991-01-01

    Observations of the Thomson scattering brightness by electrons in the inner heliosphere provide a means of probing the heliospheric electron distributions. An extensive data base of Thomson scattering observations, stretching over many years, is available from the zodiacal light photometers on board the two Helios spacecraft. A survey of these data is in progress, presenting these scattering intensities in the form of synoptic maps for successive Carrington rotations. The Thomson scattering maps reflect conditions at typically several tenths of an astronomical unit from the sun. Some representative examples from the survey in comparison with other solar/heliospheric data, such as in situ observations of the Helios plasma experiment and synoptic maps constructed from magnetic field, H alpha and K-coronameter data are presented. The comparison will provide some information about the extension of solar surface features into the inner heliosphere.

  16. Synoptic controls on the surface energy and water budgets in sub-arctic regions of Canada

    NASA Astrophysics Data System (ADS)

    Petrone, Richard M.; Rouse, Wayne R.

    2000-08-01

    An objective hybrid classification of daily surface weather maps for central and western Canadian sub-arctic locations was used to determine their dominant synoptic conditions during the snow free period. This classification yielded seven dominant synoptic types for each location during the snowmelt and snow-free periods (20 April-7 September), accounting for 90% of the days in period. The effects of source regions were used to explain the observed air mass characteristics, and their influence on the respective study locations. Cooler, drier air masses were the most frequent at both study locations. Arctic high pressure cells to the northeast brought the coolest air to the western sub-arctic site, Trail Valley Creek (TVC), Northwest Territories, while high pressure systems approaching from the northwest brought the coolest conditions to the central sub-arctic site, Churchill, Manitoba. Sub-tropical high pressure approaching from the west-southwest brought warm air to TVC, whereas stationary high pressure to the south warmed Churchill. These synoptic regimes exerted strong controls on the precipitation and evaporation components of the water balance as observed in terms of cloud cover, radiation and precipitation and evaporation efficiencies.

  17. A Regional Model Study of Synoptic Features Over West Africa

    NASA Technical Reports Server (NTRS)

    Druyan, Leonard M.; Fulakeza, Matthew; Lonergan, Patrick; Saloum, Mahaman; Hansen, James E. (Technical Monitor)

    2001-01-01

    Synoptic weather features over West Africa were studied in simulations by the regional simulation model (RM) at the NASA/Goddard Institute for Space Studies. These pioneering simulations represent the beginning of an effort to adapt regional models for weather and climate prediction over West Africa. The RM uses a cartesian grid with 50 km horizontal resolution and fifteen vertical levels. An ensemble of four simulations was forced with lateral boundary conditions from ECMWF global analyses for the period 8-22 August 1988. The simulated mid-tropospheric circulation includes the skillful development and movement of several African wave disturbances. Wavelet analysis of mid-tropospheric winds detected a dominant periodicity of about 4 days and a secondary periodicity of 5-8 days. Spatial distributions of RM precipitation and precipitation time series were validated against daily rain gauge measurements and ISCCP satellite infrared cloud imagery. The time-space distribution of simulated precipitation was made more realistic by combining the ECMWR initial conditions with a 24-hr spin-up of the moisture field and also by damping high frequency gravity waves by dynamic initialization. Model precipitation "forecasts" over the Central Sahel were correlated with observations for about three days, but reinitializing with observed data on day 5 resulted in a dramatic improvement in the precipitation validation over the remaining 9 days. Results imply that information via the lateral boundary conditions is not always sufficient to minimize departures between simulated and actual precipitation patterns for more than several days. In addition, there was some evidence that the new initialization may increase the simulations' sensitivity to the quality of lateral boundary conditions.

  18. 61 FR 25729 - Security Measures; Hellenikon International Airport, Athens, Greece

    Federal Register 2010, 2011, 2012, 2013, 2014

    1996-05-22

    ... Security Measures; Hellenikon International Airport, Athens, Greece Summary The Secretary of Transportation has now determined that Hellenikon International Airport, Athens, Greece, maintains and carries out... that Hellenikon International Airport, Athens, Greece, did not maintain and carry out...

  19. New Approaches to Object Classification in Synoptic Sky Surveys

    SciTech Connect

    Donalek, C.; Mahabal, A.; Djorgovski, S. G.; Marney, S.; Drake, A.; Glikman, E.; Graham, M. J.; Williams, R.

    2008-12-05

    Digital synoptic sky surveys pose several new object classification challenges. In surveys where real-time detection and classification of transient events is a science driver, there is a need for an effective elimination of instrument-related artifacts which can masquerade as transient sources in the detection pipeline, e.g., unremoved large cosmic rays, saturation trails, reflections, crosstalk artifacts, etc. We have implemented such an Artifact Filter, using a supervised neural network, for the real-time processing pipeline in the Palomar-Quest (PQ) survey. After the training phase, for each object it takes as input a set of measured morphological parameters and returns the probability of it being a real object. Despite the relatively low number of training cases for many kinds of artifacts, the overall artifact classification rate is around 90%, with no genuine transients misclassified during our real-time scans. Another question is how to assign an optimal star-galaxy classification in a multi-pass survey, where seeing and other conditions change between different epochs, potentially producing inconsistent classifications for the same object. We have implemented a star/galaxy multipass classifier that makes use of external and a priori knowledge to find the optimal classification from the individually derived ones. Both these techniques can be applied to other, similar surveys and data sets.

  20. The Design of Solar Synoptic Chart for Space Weather Forecast

    NASA Astrophysics Data System (ADS)

    Song, Qiao; Wang, JinSong; Feng, Xueshang; Zhang, XiaoXin

    2015-08-01

    The influence of space weather has already been an important part of our modern society. A chart with key concepts and objects in space weather is needed for space weather forecast. In this work, we search space weather liter- atures during the past forty years and investigate a variety of solar data sets, which including our own data observed by the vector magnetic field telescope and the Hα telescope at Wenquan and Shidao stations of National Center for Space Weather. Based on the literatures and data, we design the solar synoptic chart (SSC) that covers main objects of solar activities and contains images from different heights and temperatures of solar atmosphere. The SSC includes the information of active regions, coronal holes, filaments/prominences, flares and coronal mass ejections, and reveals magnetic structures from cooler photosphere to hotter corona. We use the SSC method to analyze the condition of the Sun and give two typical examples of the SSC. The result shows that the SSC is timely, comprehensive, concise and easy to understand, and it meets the needs of space weather forecast and can help improving the public education of space weather.

  1. Diurnal variation of wind-chill at Thessaloniki, Greece

    NASA Astrophysics Data System (ADS)

    Balafoutis, Ch. J.

    1989-12-01

    The diurnal variations of wind-chill at Thessaloniki, Greece, are considered using hourly data from January 1960 to December 1977. This is the first attempt in Greece to describe bioclimatic conditions using wind-chill data. The hourly values of wind-chill were calculated by Siple-Passel's formula which still appears to be most widely used. The values of wind-chill are discussed in terms of Terjung's scale. Thessaloniki does not experience “frost-bite” conditions during the coldest months but does experience “warm” conditions during the summer period. A comparison of hourly and daily mean values show that the means do not indicate the real range of wind-chill during the day.

  2. History of leucotomies in Greece.

    PubMed

    Ploumpidis, D; Tsiamis, C; Poulakou-Rebelakou, E

    2015-03-01

    In order to present the social, scientific and institutional context which permitted the use of leucotomies in Greece, we have reviewed the Archives of the Medical Associations, the medical literature of the years 1946-56, a reader's dissertation and the memoirs of two psychiatrists. More than 250 leucotomies were done in the two public psychiatric hospitals in Athens from 1947 to 1954, as well as 40 leucotomies in the public psychiatric hospital in Thessaloniki. Although aware of the side effects, psychiatrists justified the use of the procedure. The performance of leucotomies in Greece declined because of reports of the dangers of the operation and its unpredictable outcome for the patients, but mainly because of the encouraging results with psychotropic drugs in the early 1950s. PMID:25698687

  3. Ancient Celestial Spheres from Greece

    NASA Astrophysics Data System (ADS)

    Dimitrakoudis, S.; Papaspyrou, P.; Petoussis, V.; Moussas, X.

    2006-08-01

    We present several ancient celestial spheres from the 8th century B.C. found throughout Greece, mainly in Thessaly, at the temple of Itonia Athena, but also in Olympia and other places. These celestial spheres have an axis, equator and several meridians and they have several markings with the symbol of stars (today's symbol for the Sun) $\\odot$. Such instruments could have been used to measure the time, the latitude of a location, or the coordinates of stars.

  4. North Pacific Cloud Feedbacks Inferred from Synoptic-Scale Dynamic and Thermodynamic Relationships

    NASA Technical Reports Server (NTRS)

    Norris, Joel R.; Iacobellis, Sam F.

    2005-01-01

    This study analyzed daily satellite cloud observations and reanalysis dynamical parameters to determine how mid-tropospheric vertical velocity and advection over the sea surface temperature gradient control midlatitude North Pacific cloud properties. Optically thick clouds with high tops are generated by synoptic ascent, but two different cloud regimes occur under synoptic descent. When vertical motion is downward during summer, extensive stratocumulus cloudiness is associated with near surface northerly wind, while frequent cloudless pixels occur with southerly wind. Examinations of ship-reported cloud types indicates that midlatitude stratocumulus breaks up as the the boundary level decouples when it is advected equatorward over warmer water. Cumulus is prevalent under conditions of synoptic descent and cold advection during winter. Poleward advection of subtropical air over colder water causes stratification of the near-surface layer that inhibits upward mixing of moisture and suppresses cloudiness until a fog eventually forms. Averaging of cloud and radiation data into intervals of 500-hPa vertical velocity and advection over the SST gradient enables the cloud response to changes in temperature and the stratification of the lower troposphere to be investigated independent of the dynamics.

  5. Simulated life cycles of persistent anticyclonic anomalies over the North Pacific: Role of synoptic-scale eddies

    NASA Technical Reports Server (NTRS)

    Higgins, R. W.; Schubert, S. D.

    1994-01-01

    This study examines the role of synoptic-scale eddies during the development of persistent anticyclonic height anomalies over the central North Pacific in a general circulation model under perpetual January conditions. The General Circulation Model (GCM) replicates the basic characteristics of the evolution of the anomaly patterns found in observations. The life cycle is characterized by the rapid establishment of the major anomaly center and considerably longer maintenance and decay phases, which include the development of downstream anomaly centers. The simulation also shows a realistic evolution of synoptic-scale activity beginning with enhanced activity off the east coast of Asia prior to onset, followed by a northward shift of the Pacific storm track, which lasts throughout the maintenance phase. The initial enhancement of synoptic-scale eddy activity is associated with a large-scale cyclonic anomaly that developes over Siberia several days prior to the onset of the main anticyclonic anomaly over the central North Pacific. The observations, however, show considerable interdecadel variability in the details of the composite onset behavior; it is unclear whether this variability is real or whether it reflects differences in the data assimilation systems. The role of the time mean flow and synoptic-scale eddies in the development of the persistent Pacific anomalies is studied within the context of a kinetic energy budget in which the flow is decomposed into the time-mean, low-frequency (timescales longer than 10 days), and synoptic (timescales less than 6 days) components. The budget, which is carried out for the simulation at 500 mb, shows that the initial growth of the persistent anticyclonic anomalies is associated with barotropic conversions of energy, with approximately equal contributions coming from the mean flow and the synoptic-scale eddies. After onset the barotropic conversion from the mean flow dominates, whereas the decay phase is associated with

  6. Coastal and synoptic recirculation affecting air pollutants dispersion: A numerical study

    NASA Astrophysics Data System (ADS)

    Levy, Ilan; Mahrer, Yizhak; Dayan, Uri

    This study examines the spatial distribution of potential recirculation over the East Mediterranean Sea, and the combined effect of synoptic and meso-scale recirculations on plume dispersion in the region. For this purpose, three case studies are performed by the RAMS-HYPACT modeling system, each for a different synoptic scale flow pattern. Both a quantitative measure of the recirculation potential at each grid cell and particle dispersion are calculated. Although the recirculation index is an Eulerian quantity for the wind field and plume dispersion is a manifestation of the Lagrangian behavior of the wind, good correlation is found between the two. Several locations are identified as having high recirculation potential, including southern Cyprus, the coasts of Israel and Lebanon, the eastern slopes of the Judean Mountains and the Haifa Bay in particular. In the latter location, high recirculation potential could be explained by strong interaction between the land-sea surfaces, curvature of the bay and proximity of the Carmel ridge. It is shown that the synoptic and meso-scale recirculations may, under certain conditions, act together and at the same time in determining particle distribution. Under weak synoptic scale flows, particles are recirculated over the entire East Mediterranean Sea basin, returning onshore after a period of 2-3 days to join freshly emitted particles. At the same time, near-shore land-sea breeze effects cause particles to recirculate on smaller time scales of less then one day, sometimes passing as much as three times over the same airshed. A single elevated emission source is shown to have the potential to impair air quality at a coastal strip as long as 100-200 km upon returning onshore.

  7. Spatio-temporal dynamics and synoptic characteristics of wet and drought extremes in Northern Eurasia

    NASA Astrophysics Data System (ADS)

    Utkuzova, Dilyara; Khan, Valentina

    2015-04-01

    Synoptical-statistical analysis has been conducted using SPI index calculated for 478 stations with records from 1966 through 2013. Different parameters of SPI frequency distribution and long-term tendencies were calculated as well as spatial characteristics indicating drought and wetness propagation. Results of analysis demonstrate that during last years there is a tendency of increasing of the intensity of draught and wetness extremes over Russia. There are fewer droughts in the northern regions. The drought propagation for the European territory of Russia is decreasing in June and August, and increasing in July. The situation is opposite for the wetness tendencies. For the Asian territory of Russia, the drought propagation is significantly increasing in July along with decreasing wetness trend. Synoptic conditions favorable for the formation of wet and drought extremes were identified by comparing synoptic charts with the spatial patterns of SPI. For synoptic analysis, episodes of extremely wet (6 episodes for the APR and 7 episodes for the EPR) and drought (6 episodes for the APR and 6 for the EPR) events were classified using A. Katz' typology of weather regimes. For European part of Russia, extreme DROUGHT events are linked to the weather type named "MIXED", for Asian part of Russia - the type "CENTRAL". For European part of Russia, extreme WET events associated with "CENTRAL" type. There is a displacement of the planetary frontal zone into southward direction approximately for 5-25 degrees relatively to normal climatological position during WET extreme events linked to «EASTERN» classification type. Intercomparison of SPI calculated on the base of NOAA NCEP CPC CAMS for the same period and with the resolution 0,5 degree, month precipitation data, Era-Interim Daily fields archive for the period 1979-2014 with the resolution 0,5 degree reanalysis and observational precipitation data was done. The results of comparative analysis has been discussed.

  8. Health inequalities after austerity in Greece.

    PubMed

    Karanikolos, Marina; Kentikelenis, Alexander

    2016-01-01

    Since the beginning of economic crisis, Greece has been experiencing unprecedented levels of unemployment and profound cuts to public budgets. Health and welfare sectors were subject to severe austerity measures, which have endangered provision of as well as access to services, potentially widening health inequality gap. European Union Statistics on Income and Living Conditions data show that the proportion of individuals on low incomes reporting unmet medical need due to cost doubled from 7 % in 2008 to 13.9 % in 2013, while the relative gap in access to care between the richest and poorest population groups increased almost ten-fold. In addition, austerity cuts have affected other vulnerable groups, such as undocumented migrants and injecting drug users. Steps have been taken in attempt to mitigate the impact of the austerity, however addressing the growing health inequality gap will require persistent effort of the country's leadership for years to come. PMID:27245588

  9. Access to health for refugees in Greece: lessons in inequalities.

    PubMed

    Kousoulis, Antonis A; Ioakeim-Ioannidou, Myrsini; Economopoulos, Konstantinos P

    2016-01-01

    Eastern Greek islands have been direct passageways of (mainly Syrian) refugees to the European continent over the past year. However, basic medical care has been insufficient. Despite calls for reform, the Greek healthcare system has for many years been costly and dysfunctional, lacking universal equity of access. Thus, mainly volunteers look after the refugee camps in the Greek islands under adverse conditions. Communicable diseases, trauma related injuries and mental health problems are the most common issues facing the refugees. The rapid changes in the epidemiology of multiple conditions that are seen in countries with high immigration rates, like Greece, demand pragmatic solutions. Best available knowledge should be used in delivering health interventions. So far, Greece is failed by international aid, and cross-border policies have not effectively tackled underlying reasons for ill-health in this context, like poverty, conflict and equity of access. PMID:27485633

  10. Uncertainties in Solar Synoptic Maps and their Effect on Models.

    NASA Astrophysics Data System (ADS)

    Pevtsov, Alexei; Petrie, Gordon; Bertello, Luca

    Synoptic charts of the photospheric magnetic flux are used widely in modeling the magnetic field in the corona and the heliosphere. Recently, the National Solar Observatory began producing accompanying maps of uncertainties (http://solis.nso.edu/0/ermaps/6302l_er2138-2157.html), which can be used to estimate the uncertainty in the results of coronal models. These maps of uncertainties represent the spatial variance of the magnetic flux distribution that contributes to each bin in the synoptic chart. We will describe a method to compute synoptic magnetic flux spatial variance charts, and discuss the effects of these uncertainties on models of the coronal magnetic field and the solar wind speed.

  11. Solar synoptic telescope. Characteristics, possibilities, and limits of design

    NASA Astrophysics Data System (ADS)

    Klvaňa, M.; Sobotka, M.; Švanda, M.

    2011-10-01

    A rapid evolution of electronics and information technologies makes it possible to use new original designs of synoptic telescopes for solar observations, to increase the demands on their functions, and to fully automate the observation. However, there are hardware and software limits that strongly influence the working capabilities of synoptic telescopes. In this contribution, we analyze relationships between the synoptic telescope's characteristics, the parameters of image digitization, the control, the achievable degree of automation of observations, and the possibilities to implement functions connected with the solar activity monitoring and image archiving. The principles listed above serve as a basis for the design study of the Auxiliary Full-Disc Telescope for the European Solar Telescope (EST), a pan-European project of a large 4-meter solar telescope.

  12. Institutional child abuse in Greece: some preliminary findings.

    PubMed

    Agathonos, H

    1983-01-01

    A long-term study on child abuse and neglect in Greece is being carried out at the Institute of Child Health, Athens. A multidisciplinary team is investigating the nature of the problem in Greece, is trying a system of therapeutic intervention to families, is evaluating the adequacy of child protection as it is used in child abuse and neglect, and is examining the efficacy of the law. During a one year period, 5 children cared for in institutions were referred to the program. All were boys. All were children with minor or major handicaps. Two of died from the abusive incident. A study of the circumstances of the injury, and of the conditions in Greek institutions, supports the idea that institutional and family child abuse share many common characteristics. Special mention is made of the Greek circumstances pertaining to child protection and the law. PMID:6226340

  13. Identifying relationships between baseflow geochemistry and land use with synoptic sampling and R-mode factor analysis.

    PubMed

    Wayland, Karen G; Long, David T; Hyndman, David W; Pijanowski, Bryan C; Woodhams, Sarah M; Haack, Sheridan K

    2003-01-01

    The relationship between land use and stream chemistry is often explored through synoptic sampling of rivers at baseflow conditions. However, baseflow chemistry is likely to vary temporally and spatially with land use. The purpose of our study is to examine the usefulness of the synoptic sampling approach for identifying the relationship between complex land use configurations and stream water quality. This study compares biogeochemical data from three synoptic sampling events representing the temporal variability of baseflow chemistry and land use using R-mode factor analysis. Separate R-mode factor analyses of the data from individual sampling events yielded only two consistent factors. Agricultural activity was associated with elevated levels of Ca2+, Mg2+, alkalinity, and frequently K+, SO4(2-), and NO3-. Urban areas were associated with higher concentrations of Na+, K+, and Cl-. Other retained factors were not consistent among sampling events, and some factors were difficult to interpret in the context of biogeochemical sources and processes. When all data were combined, further associations were revealed such as an inverse relationship between the proportion of wetlands and stream nitrate concentrations. We also found that barren lands were associated with elevated sulfate levels. This research suggests that an individual sampling event is unlikely to characterize adequately the complex processes controlling interactions between land use and stream chemistry. Combining data collected over two years during three synoptic sampling events appears to enhance our ability to understand processes linking stream chemistry and land use. PMID:12549557

  14. Sensor Development for the Large Synoptic Survey Telescope.

    SciTech Connect

    O'Connor,P.; Radeka, V.; Takacs, P.

    2007-06-07

    The Large Synoptic Survey project proposes to build an 8m-class ground-based telescope with a dedicated wide field camera. The camera consists of a large focal plane mosaic composed of multi-output CCDs with extended red response. Design considerations and preliminary characterization results for the sensors are presented in this contribution to the Workshop.

  15. A synoptic approach to sun-weather investigations

    NASA Technical Reports Server (NTRS)

    Wilcox, J. M.

    1976-01-01

    The advantages of a regular program of daily observations of the magnetosphere, ionosphere and atmosphere are described. Such synoptic observations may be one of the best routes to understanding the physical mechanisms involved in sun-weather influences. Some specific examples of such observations are given.

  16. Blood transfusion economics in Greece.

    PubMed

    Kyriopoulos, J E; Michail-Merianou, V; Gitona, M

    1995-01-01

    This paper describes the organizational structure and the economic impact of blood donation and transfusion in Greece and discusses some alternative aspects of its financing and its costing policy. The cost of blood transfusion is rising in Greece and amounts to nearly 15 billion drachmas per year due to the constant increase in demand and consequently, the price of each unit of blood. The production and distribution of blood on national scale involves meeting the demand for 500.000 units. Blood is mostly given by the friends and relatives of patients (55%) and by voluntary blood donation (30%). Approximately 50% of the blood produced is used in surgery, 20% for cases of beta-thalassaemia, 10% for emergencies and 20% for internal medicine cases. The blood transfusion system is totally funded by the state budget and the value to users is free of charge. The way in which blood is collected and processed differs from one geographical area to another and the unit cost depends on the size of the department concerned, ranging from 60-150 $. The need to control costs and restrain expenditure, in conjunction with guarantees of sufficiency and quality, makes it essential that measures should be taken to introduce economies of scale and encourage competition among blood providers, for increased production, components preparation and rational usage of blood. The introduction of a costing policy becomes necessary in this effort to achieve cost-containment techniques. PMID:8581182

  17. Metallic mineral resources of Greece

    NASA Astrophysics Data System (ADS)

    Tsirambides, Ananias; Filippidis, Anestis

    2012-12-01

    Today Greece produces and exports raw bauxite and alumina, concentrates of galena and sphalerite and ferronickel. The indicated reserves of bauxite, located in the Mt Helikon-Mt Parnassus-Mt Giona-Mt Iti zone, are estimated at approximately 100 mt and those of aluminum 2.5 mt. The probable and indicated reserves of lead and zinc from Chalkidiki are approximately 3.125 mt. The total production of concentrates of galena and sphalerite is approximately 220,000 tpa. The proven reserves of nickel are approximately 1.392 mt and the production of ferronickel is approximately 18,500 tpa. Production of copper, silver and gold is pending in 2015. The probable and indicated reserves of copper from Skouries Chalkidiki are approximately 1.943 mt. In the Prefecture Units of Chalkidiki and Evros the probable and indicated reserves of gold are approximately 19.37 million ounces and those of silver 131.6 million ounces. Chromium, manganese and molybdenum present good prospects of exploitation. Calculated at current prices, the total gross value of the probable and indicated reserves of the metallic minerals of Greece is €79.4 billion.

  18. Synoptic typing and its application to the investigation of weather - air pollution relationships in Kuwait

    NASA Astrophysics Data System (ADS)

    Al-Shatti, A.; Phillips, I. D.; Baker, J.

    2009-04-01

    Principal components analysis and cluster analysis of surface meteorological data were used to derive the different air mass types for Kuwait. The air mass types were analysed in terms of their mean meteorological and associated weather chart characteristics in order to relate them to their different synoptic situations. The air mass types were subsequently analysed with air pollutant concentration data. Here we report on the identified air mass types, their seasonal dependence and their pollution characteristics. Analysis of the air mass types according to pollutant mean and extreme values helps to identify the different meteorological and transport conditions influencing pollution in this region.

  19. Atmospheric heat transfer to the Arctic under main synoptic processes

    NASA Astrophysics Data System (ADS)

    Yurova, Alla; Gnatiuk, Natalia; Bobylev, Leonid; Zhu, Yali

    2016-04-01

    Arctic - mid-latitude teleconnections are operating in both ways and behind them are potentially some causes of the enhanced Arctic warming (e.g., through heat transfer from lower to higher latitudes) and the feedbacks from the Arctic climate to the mid-latitude weather patterns. In order to explain the variability of the surface air temperature in the Arctic, we aim to analyse the typical synoptic situations that, we hypothesize, are characterized by a specific patterns of heat exchange between the Arctic and mid-latitudes. According to classification of synoptic processes in the Arctic developed at the Arctic and Antarctic Research Institute (AARI) in St. Petersburg major typical groups of synoptic situations in the Arctic are few (six). They correspond to position and intensity of low- and high-pressure centres. Therefore, the whole data sample for the winter period for the entire period of instrumental observations (archive exists back to 1939) can be split into six groups that sub-sample each of six groups/types of synoptic situations. Then heat transfer to the Arctic can be estimated as the divergence of the horizontal (advective) heat flux (the product of wind speed and temperature gradient) within each vertical atmospheric layer, which is calculated based on the ERA Interim Reanalysis data for the winter season (1979-now). Mapping heat divergence fields will reveal the main mid-latitude sources of heat transported to the Arctic, average for the whole data sample and for each of the six main groups of synoptic situations. This work was supported by RFBR grants 16-55-53031

  20. Greece: Health system review.

    PubMed

    Economou, Charalambos

    2010-01-01

    financing and equity in access to health care services. Efficiency is in question due to the lack of incentives to improve performance in the public sector. Mechanisms for needs assessment and priority-setting are underdeveloped and, as a consequence, the regional distribution of health resources is unequal. Centralization of the system is coupled with a lack of planning and coordination, and limited managerial and administrative capacity. In addition, the oversupply of physicians, the absence of a referral system, and irrational pricing and reimbursement policies are factors encouraging under-the-table payments and the black economy. These shortcomings result in low satisfaction with the health care system expressed by citizens. The landmark in the development of the Greek health care system was the creation of the national health system (ESY) in 1983. This report describes the development of the ESY at the structural level and generally, the process of implementing reforms. The strategic targets of health reform initiatives have been to structure a unified health care sector along the lines of the original ESY proposal and to cope with current inefficiencies. However, the three reforms attempted in the 1990s were never fully implemented, while the ambitious reform project of the period 2000–2004, which provided for the regionalization of the system, new management structures, prospective reimbursement, new employment conditions for hospital doctors, modernization of public health services and reorganization of primary health care, was abolished after the elections of 2004 and a change in government. While the new strategy, launched in 2005 with the stated aims of securing the financial viability of the health care system in the short term and its sustainability in the long term, addressed specific weaknesses, it has been rather controversial: the introduction of a centralized administrative public procurement system, the development of public–private partnerships

  1. An analysis of the synoptic and climatological applicability of circulation type classifications for Ireland

    NASA Astrophysics Data System (ADS)

    Broderick, Ciaran; Fealy, Rowan

    2013-04-01

    Circulation type classifications (CTCs) compiled as part of the COST733 Action, entitled 'Harmonisation and Application of Weather Type Classifications for European Regions', are examined for their synoptic and climatological applicability to Ireland based on their ability to characterise surface temperature and precipitation. In all 16 different objective classification schemes, representative of four different methodological approaches to circulation typing (optimization algorithms, threshold based methods, eigenvector techniques and leader algorithms) are considered. Several statistical metrics which variously quantify the ability of CTCs to discretize daily data into well-defined homogeneous groups are used to evaluate and compare different approaches to synoptic typing. The records from 14 meteorological stations located across the island of Ireland are used in the study. The results indicate that while it was not possible to identify a single optimum classification or approach to circulation typing - conditional on the location and surface variables considered - a number of general assertions regarding the performance of different schemes can be made. The findings for surface temperature indicate that that those classifications based on predefined thresholds (e.g. Litynski, GrossWetterTypes and original Lamb Weather Type) perform well, as do the Kruizinga and Lund classification schemes. Similarly for precipitation predefined type classifications return high skill scores, as do those classifications derived using some optimization procedure (e.g. SANDRA, Self Organizing Maps and K-Means clustering). For both temperature and precipitation the results generally indicate that the classifications perform best for the winter season - reflecting the closer coupling between large-scale circulation and surface conditions during this period. In contrast to the findings for temperature, spatial patterns in the performance of classifications were more evident for

  2. Controls on Synoptic Scale Variability in Atmospheric Water Vapor Stable Isotopologues from Mauna Loa Observatory, Hawaii (Invited)

    NASA Astrophysics Data System (ADS)

    Hurley, J. V.; Galewsky, J.; Noone, D. C.; Worden, J.; Johnson, L. R.

    2010-12-01

    The Havaiki campaign, 9 October to 6 November, 2008, included continuous (6 seconds) in-situ measurement of water vapor stable isotopic ratios at the NOAA Mauna Loa Observatory (MLO), Hawaii. δD correlates with water vapor mixing ratios, and is characterized by both diurnal fluctuations and synoptic scale variability. Daily fluctuations are related to day-time lifting and night-time compression of the trade inversion. We focus on the synoptic variability of night-time δD values, which is more representative of the free troposphere. To do so, we determined last saturation conditions for air at MLO using both Lagrangian back-trajectory and Eulerian GCM-based techniques. Last saturation of air at MLO occurs primarily in the extra-tropical middle-upper troposphere, along mid-latitude baroclinic zones, and secondarily near Hawaii within mesoscale convective systems. Synoptic-scale periods of lower (elevated) δD values at MLO correspond to extra-tropical (near-Hawaii) last saturation. To assess the influence of mixing on water vapor δD at MLO, we reconstructed Havaiki humidity and δD values from both our Lagrangian and Eulerian last saturation model results. The Eulerian based reconstructions, which account for mixing, better represent the observed Havaiki δD values. The Lagrangian approach does not account for mixing and overestimates the observed variability. These results suggest that mixing plays a critical role in setting the water vapor δD of sub-saturated air in the subtropical free tropopshere. To weigh the influences that large-scale circulation or the pre-saturation water vapor δD values have on the observed synoptic variability of δD at MLO, we conducted δD reconstruction experiments. First, we held constant the pre-saturation water vapor δD, varied the last saturation distributions, and were able to reproduce the observed synoptic variability. In the second experiment, we held last saturation distributions constant, varied the pre-saturation

  3. Lightning characteristics over the eastern coast of the Mediterranean during different synoptic systems

    NASA Astrophysics Data System (ADS)

    Ben Ami, Y.; Altaratz, O.; Yair, Y.; Koren, I.

    2015-11-01

    Thunderstorm activity takes place in the eastern Mediterranean mainly through the boreal fall and winter seasons during synoptic systems of Red Sea Trough (RST), Red Sea Trough that closed a low over the sea (RST-CL), and Cyprus Low (during fall - FCL and winter - WCL). In this work we used the Israeli Lightning Location System ground strokes data set, between October 2004 and December 2010, for studying the properties of lightning strokes and their link to the thermodynamic conditions in each synoptic system. It is shown that lightning activity dominates over sea during WCL and FCL systems (with maximum values of 1.5 in WCL, and 2.2 km-2 day-1 in FCL) and have a dominant component over land during the RST and RST-CL days. The stronger instability (high Convective Available Potential Energy (CAPE) values of 762 ± 457 J kg-1) during RST-CL days together with the higher altitude of the clouds' mixed-phase region (3.6 ± 0.3 km), result in a slightly higher density of ground strokes during this system but a lower fraction of positive ground strokes (3 ± 0.5 %). In general the fraction of positive strokes was found to be inversely correlated with the sea surface temperature: it increases from 1.2 % in early fall to 17.7 % in late winter, during FCL and WCL days. This change could be linked to the variation in the charge center's vertical location during those months. The diurnal cycle in the lightning activity was examined for each synoptic system. During WCL conditions, no preferred times were found through the day, as it relates to the random passage timing of the frontal systems over the study region. During the fall systems (FCL and RST-CL) there is a peak in lightning activity during the morning hours, probably related to the enhanced convection driven by the convergence between the eastern land breeze and the western synoptic winds. The distributions of peak currents in FCL and WCL systems also change from fall to winter and include more strong negative and

  4. Carbon dioxide fluxes associated with synoptic weather events over a southern inland water

    NASA Astrophysics Data System (ADS)

    Liu, H.; Zhang, Q.; Gao, Z.

    2015-12-01

    Evidence indicates that inland waters play an important role in regional and global carbon budget through releasing a substantial carbon into the atmosphere. To better quantify how environmental variables affect CO2 exchange between inland waters and the atmosphere and its temporal variations, we have conducted direct, long-term measurements of CO2 fluxes across the water-atmosphere interface over a large southern open water of Ross Barnett Reservoir in central Mississippi. Our data indicate that large CO2 flux pulses occurred occasionally throughout the course of a year with the duration of a few days for each pulse. Here we analyzed and demonstrated that these CO2 flux pulses were associated with the passages of synoptic weather events. Our preliminary results indicated that these synoptic weather events (e.g., extratropical clones and cold air bursts) led to the enhanced mechanical mixing due to increasing wind speeds and the instability of the atmospheric surface layer due to the decreasing air temperature. As a consequence, in-water processes were also substantially altered accordingly. Due to the dramatic decrease in air temperature caused by the events, the temperature in the water surface layer was largely reduced, generating in-water convection conditions and thus leading to the increased depths of the mixing layer in the water, as reflected by the water temperature profiles. The enhanced mechanical mixing in the atmospheric surface layer may have further contributed to the deepened mixing layer in the water. Our suggestions suggest that high CO2 effluxes during the pulse events were largely attributed to changes in the water-side physical processes that are directly linked to rapid changes in atmospheric processes associated with synoptic weather events. Given its substantial contribution of CO2 flux pulses to carbon emission, such physical processes should be taken into account when carbon emissions from inland waters are quantified.

  5. Variants of synoptic-scale weather patterns inducing heavy steady rains

    NASA Astrophysics Data System (ADS)

    Kaspar, M.; Müller, M.

    2009-04-01

    Previous studies confirmed the close relationship between synoptic-scale meteorological conditions and the occurrence of heavy widespread and steady rains in the Czech Republic. We showed that some dynamic and thermodynamic variables had regularly reached abnormal values in specific regions before and during extreme precipitation events. On the other hand, these anomalies partly varied among individual events. The presented study utilizes the results and is aimed at the objective classification of causal synoptic-scale weather patterns. We compiled the set of extreme precipitation events that had affected the Czech Republic during warm half-years from 1958 to 2002. In order to classify the events, we employed re-analyses ERA-40. We focused on the horizontal components of moisture flux, anomalies of which are the typical features of the most significant events and are responsible for an increased water vapour supply into the rainfall area. For compiled events, we quantified the extremeness of the anomalies by distribution function in individual grid points. We applied a divisive and fuzzy clustering method in order to cluster the events in terms of the extremeness of the horizontal components of moisture flux within the rainfall area from a day before to two days after the precipitation onset. We identified and defined four variants of causal synoptic-scale weather patterns. The first two variants are associated with the passage of an extra-tropical cyclone across Central Europe. The differences between the variants consist in the cyclone track. The third variant is characterised by cold frontal waves repeatedly affecting heavy rain sites. The forth variant is similar to the third variant but is rounded off by the passage of a frontal wave cyclone. The classification method will be briefly presented and all four variants will be described using average thermo-baric fields. Further applications of the classification method will be also mentioned.

  6. Solar Synoptic Maps from the San Fernando Observatory

    NASA Astrophysics Data System (ADS)

    Hodgson, John, II; Chapman, G.; Preminger, D.; Cookson, A.

    2011-05-01

    We are developing a set of synoptic image maps compiled from daily photometric images taken at the San Fernando Observatory. Our initial maps show the progression of solar features across the central meridian for approximately one solar rotation. The red continuum maps show the photometric contrast of solar features in the photosphere while the Ca II K-line maps show the same in the lower chromosphere. Comparing these maps with each other, and with those of other solar groups, will yield information regarding the evolutionary patterns of solar activity at different heights of the solar atmosphere. This is a first step toward a comprehensive set of synoptic maps covering the period from mid-solar cycle 22 in 1988 to the present. This work has been supported in part by NSF grant ATM-0848518.

  7. SOLIS: A Modern Facility for Synoptic Solar Observations

    NASA Astrophysics Data System (ADS)

    Keller, C. U.

    1998-03-01

    SOLIS (Synoptic Optical Long-term Investigations of the Sun) is a suite of instruments that will modernize and greatly improve synoptic solar observations carried out by the National Solar Observatory. It will provide fundamental data necessary to understand the solar activity cycle, sudden energy releases in the solar atmosphere, and solar spectral irradiance changes. State-of-the-art instrumentation and data collection techniques will be employed to enhance both the quality and quantity of data. A high degree of automation and remote control will provide faster user access to data and flexible interaction with the data-collection process. The instruments include a vector spectromagnetograph that will measure the magnetic field strength and direction over the full solar disk in 15 minutes, a full disk patrol delivering digital images in various spectral lines at a high cadence, and a Sun-as-a-star precision spectrometer to measure changes in many spectral lines.

  8. Web-based synoptic reporting for cancer checklists

    PubMed Central

    Baskovich, Brett W.; Allan, Robert W.

    2011-01-01

    Background: The surgical pathology report remains the primary source for information to guide the treatment of patients with cancer. Failure to report critical elements in a cancer report is an increasing problem in pathology because of the heightened complexity of these reports and number of elements that are important for patient care. The American College of Surgeons Commission on Cancer (ACS-CoC) in concert with the College of American Pathologists (CAP) developed checklists that contain all of the scientifically validated data elements that are to be reported for cancer specimens. Most institutions do not as of yet have pathology information systems in which CAP checklists are embedded into the laboratory information system (LIS). Entering the required elements often requires extensive text editing, secretarial support and deletion of extraneous elements that can be an arduous task. Materials and Methods: We sought to develop a web-based system that was available throughout the workstations in our department and was capable of generating synoptic reports based on the CAP guidelines. The program was written in a manner that allowed automatic generation of the web-based checklists through a parsing algorithm. Results: Multiple web-based synoptic report generators have been developed to encompass required elements of cancer synoptic reports as required by the ACS-CoC/ CAP. In addition, utilizing the same program, report generators for certain molecular tests (KRAS mutation) and FISH studies (UroVysiontm) have also been developed. The output of these reports can be cut-and-pasted into any text-based anatomic pathology LIS. In addition, the elements can be compiled in a database. Conclusions: We describe a simple method to automate the development of web-based synoptic reports that can be entered into the anatomic pathology LIS and database. PMID:21572504

  9. Satellite observations of surface temperature patterns induced by synoptic circulation over the Eastern Mediterranean

    NASA Astrophysics Data System (ADS)

    Lensky, Itamar; Dayan, Uri

    2013-04-01

    Land Surface Temperature (LST) controls most physical and biological processes on Earth. Knowledge of the LST at high spatial resolution enables representation of different climate regimes. The main factors controlling LST are the seasonal and diurnal cycles, land cover, cloud cover, and atmospheric processes at several scales. Lensky and Dayan analyzed atmospheric processes at the topoclimatic scale, and the mesoscale (Lensky and Dayan 2011, 2012). Here we will demonstrate an analysis of the spatial distribution of LST anomaly as affected by typical synoptic circulation patterns over the Eastern Mediterranean (EM). LST anomaly is defined as the difference between daily and climatological LST. Using LST anomaly reduces the effects of land cover and the seasonal and diurnal cycles, enabling a better detection of surface temperature patterns induced by synoptic circulation. In this study we used all available 2000-2012 NASA daily MODIS LST data over the EM, together with NCEP/NCAR Reanalysis data of SLP, surface winds and Omega (at 700hPa). We will present two frequent synoptic circulation patterns as classified by Levy and Dayan (2008) to demonstrate the LST patterns induced by synoptic circulation over the EM. The first is the "Red Sea Trough" (RST) with eastern axis, which is an extension of a low surface pressure from a tropical depression toward the Red Sea, penetrating up north as far as Turkey. It migrates from south to north and mostly frequent during the autumn. The axis of the RST separates distinctively between regions of positive (warm) anomalies over Turkey and regions of negative anomalies (cold) over Egypt induced by the wind flow from both sides of the axis. The second synoptic circulation pattern is "shallow Cyprus low to the north", which is a disturbance of the polar front extending southward. This synoptic system some times migrates over the Mediterranean eastward toward the EM during the winter season. The strong northwesterly flow featuring the

  10. The coupling of synoptic and valley winds in the Tennessee Valley

    SciTech Connect

    Doran, J.C.; Whiteman, C.D.

    1992-09-01

    The interaction of winds in a valley with the winds above the valley is of interest for both practical and theoretical reasons. For example, the forecasting of conditions affecting air quality,, emergency preparedness, or aerial spraying of pesticides requires the ability to relate local valley circulations to ambient synoptic conditions. While empirically derived relationships may be useful, it is also desirable to develop an understanding of the mechanisms responsible for the observed behavior. In this paper we combine results from analyses of measurements and model-generated data to provide insight into factors affecting the climatology of the winds in the Tennessee Valley. We discuss four mechanisms that can determine the behavior of winds in a valley. The conditions can be illustrated in terms of the expected joint frequency distributions of the surface and geostrophic winds.

  11. Aspects of cold intrusions over Greece during autumn

    NASA Astrophysics Data System (ADS)

    Mita, Constantina; Marinaki, Aggeliki; Zeini, Konstantina; Konstantara, Metaxia

    2010-05-01

    This study is focused on the description of atmospheric disturbances that caused intense cold intrusions over Greece during autumn for a period of 25 years (1982-2006). The study was based on data analysis from the meteorological station network of the Hellenic National Meteorological Service (HNMS) and the European Centre for Medium Range Weather Forecasts (ECMWF). Initially, the days with temperature at the isobaric surface of 850 hPa less or equal to the mean temperature for the 10-day period the day under investigation belongs to are isolated, composing a new confined data set which was further used. An event of intense cold intrusion is identified based on a subjective set of criteria, considering the temperature decrease at the level of 850 hPa and its duration. In particular, the criteria that were used to identify a cold intrusion were: temperature variation between two successive days at the isobaric level of 850 hPa being equal or greater than 50 C at least once during the event and duration of the event of at least two successive days with continuous temperature decrease. Additionally, the synoptic analysis of the atmospheric disturbances involved using weather charts from ECMWF, revealed that all cases were related to low pressure systems at the level of 500 hPa, accompanied by cold air masses. Moreover, a methodology proposed to classify the cold intrusions based on general circulation characteristics of the atmosphere, resulted in seven major categories. More than half of the events belong in two categories, originated northwest of the greater Greek area (Greece and parts of neighbouring countries), between 400 and 600 N. Further analysis indicated that the frequency of events increases from September to November and the majority of the events lasted two to three days. Additionally, the non-parametric Mann-Kendall test was used for the investigation of the statistical significance of the trends appearing in the results. The tests revealed that over

  12. Winter synoptic weather types in Catalonia (NE Spain) and their linkage with minimum temperature anomalies

    NASA Astrophysics Data System (ADS)

    Serra, C.; Mills, G. Fernàndez; Periago, M. C.; Lana, X.

    1999-12-01

    An objective classification of winter synoptic weather types in Catalonia (NE Spain) is obtained by means of the principal component analysis of daily variables followed by cluster analysis based on Average Linkage and K-Means methods. The period analysed includes days belonging to December, January and February, from 1976 to 1980. The data list consists of thermal, pressure, cloud cover, humidity, wind and precipitation values recorded at four different stations in Catalonia. The classification includes 14 clusters which accurately explain the winter synoptic variety of the country. All cluster features are discussed in detail and a study concerning transitions between these clusters is presented. Three groups (1, 3 and 7) are related to high pressure weather types, clusters 4, 5 and 8 to cold sectors of mid-latitude depressions and clusters 2 and 9 can be associated with cyclonic conditions with western circulation. The weather types related to extended precipitation are included in clusters 6 and 10 which are linked to eastern surface circulation. The obtained classification is then applied in a study concerning daily minimum temperature anomalies. The spatial distribution of these anomalies are analysed for each significant weather type. The clusters related to widely extended frost risk are finally identified (groups 4, 8 and 14).

  13. Torrential rainfall in northeast of the Iberian Peninsula: synoptic patterns and WeMO influence

    NASA Astrophysics Data System (ADS)

    Martin-Vide, J.; Sanchez-Lorenzo, A.; Lopez-Bustins, J. A.; Cordobilla, M. J.; Garcia-Manuel, A.; Raso, J. M.

    2008-06-01

    This study presents a catalogue of synoptic patterns of torrential rainfall in northeast of the Iberian Peninsula (IP). These circulation patterns were obtained by applying a T-mode Principal Component Analysis (PCA) to a daily data grid (NCEP/NCAR reanalysis) at sea level pressure (SLP). The analysis made use of 304 days which recorded >100 mm in one or more stations in provinces of Barcelona, Girona and Tarragona (coastland area of Catalonia) throughout the 1950-2005 period. The catalogue comprises 7 circulation patterns showing a great variety of atmospheric conditions and seasonal or monthly distribution. Likewise, we computed the mean index value of the Western Mediterranean Oscillation index (WeMOi) for the synoptic patterns obtained by averaging all days grouped in each pattern. The results showed a clear association between the negative values of this teleconnection index and torrential rainfall in northeast of the IP. We therefore put forward the WeMO as an essential tool for forecasting heavy rainfall in northeast of Spain.

  14. GREECE Sounding Rocket Mission Overview

    NASA Astrophysics Data System (ADS)

    Samara, M.; Michell, R.; Grubbs, G. A., II; Bonnell, J. W.; Ogasawara, K.; Hampton, D. L.; Jahn, J. M.; Donovan, E.; Gustavsson, B.; Lanchester, B. S.; McHarg, M. G.; Spanswick, E.; Trondsen, T. S.; Valek, P. W.

    2014-12-01

    On 03 March 2014 at 11:09:50 UT the Ground-to-Rocket Electrodynamics-Electrons Correlative Experiment (GREECE) sounding rocket successfully launched from Poker Flat, Alaska . It reached an apogee of approximately 335 km over the native village of Venetie during a dynamic post-midnight auroral event. A wide range of precipitating electrons were measured with the Acute Precipitating Electron Spectrometer (APES) and Medium-energy Electron SPectrometer (MESP), cumulatively covering 300 ev to 200 keV in varying time resolutions. DC to low frequency electric and magnetic fields were measured at the same time and a langmuir probe was also employed. In addition to the on board instrumentation a suite of ground based imagers was deployed under apogee. We used several electron-multiplying charge-coupled devices (EMCCDs) with different filters and field of views imaging along magnetic zenith. This yielded multi-emission line information about the auroral brightness at the magnetic footprint of the rocket critical for our main goal of exploring the correlation of the sheer flows often observed in high resolution imagery during aurora and the in situ signatures of precipitating particles and waves. The instruments used will be discussed in further detail along with preliminary results of an event rich in particle and wave signatures.

  15. Greece licensing round to focus on western sedimentary basins

    SciTech Connect

    Roussos, N.; Marnelis, F. )

    1995-03-06

    New opportunities for international oil companies to explore for hydrocarbons in Greece will emerge shortly. Parliament ratified a new petroleum law in January 1995, and DEP-EKY SA will undertake an international licensing round for offshore-onshore areas mainly in western Greece during second half 1995. The paper describes the fold and thrust belt of western Greece; the Katakolon oil field; the tertiary basins of eastern Greece; the Prinos and Prinos North oil fields; and the Epanomi gas field.

  16. Inferring Rotation Periods of Young Stars from Synoptic Observations

    NASA Astrophysics Data System (ADS)

    Hartigan, Patrick; Johns-Krull, Christopher M.; Scowen, Paul

    2012-04-01

    Using known distributions for the periods, amplitudes and light-curve shapes of young stars, we examine how well one could measure periods of these objects in the upcoming era of large synoptic surveys. Surveys like the LSST should be able to recover accurate rotation periods for over 90% of targets of interest in regions near to massive-star formation. That information will usher in a new era in our understanding of how the angular momentum of a young star/disk system evolves with time.

  17. Extreme temperature contrast of the year 2012 in Greece: An exceptionally cold winter and a record breaking summer

    NASA Astrophysics Data System (ADS)

    Tolika, Konstantia; Anagnostopoulou, Christina; Maheras, Panagiotis; Velikou, Kondylia

    2013-04-01

    During the past decade several regions all over Europe have experienced severe heat waves with serious social and environmental impacts. The year of 2003 was characterized by record breaking high temperatures for central Europe, while the year of 2007 was a remarkably warm year of the majority of the Eastern Mediterranean. During this year, three major heat waves were detected in Greece during summer and abnormally high temperatures were also observed through the cold season of 2007. It was found that the winter minimum temperatures were statistically more extreme than the summer maxima. Moreover, exceptionally high maximum and minimum temperatures occurred in November of 2010 affection the entire Greek region while September of the following year was also characterized by large departures of maximum temperatures from the long term mean values and the highest minimum temperature average in comparison to the reference period 1958-2000. The past year (2012) could also be characterized as a year of extremes. This time a temperature contrast was detected in the domain of study with a prolonged cold - season spell during winter and new record - breaking extreme maximum and minimum summer temperatures. More specifically it was found that the summer of 2012 was the warmest one since 1958. The whole season was characterized by long - lasting warm conditions with large departures from the long term (up to 4oC for Tmax) and this warming phenomenon was more intense during July and August. In contrast the winter season (December 2011 - February 2012) was found to be in the ten coldest winters of the last 55 years. The departures from the mean are lower than summer (1oC to 1.5oC negative anomalies) but most of the days were found to have lower Tmax, Tmin and Tmean values than the average daily temperatures of the period 1958-2000. Finally, it is worth mentioning that the year of 2012 was characterized by the highest annual temperature range reaching up to 26oC in several

  18. Synoptic Drivers of Bering Strait Wave States, Fall 2011

    NASA Astrophysics Data System (ADS)

    Atkinson, D. E.

    2011-12-01

    The Bering Strait region of western Alaska, as the single point of entry to the Arctic from the Pacific, represents an important focal point of activity that ranges from heavy transport operations, such bulk ore carriers as to Teck Alaska Red Dog mine, to Arctic tourism activities, and subsistence fishing and hunting carried out by local residents. Much of that activity is set to increase in the coming years as sea ice continues to recede, allowing greater access to transport and resources in the Arctic Ocean and its marginal seas. The presence of annual sea ice cover has greatly limited the deployment of marine monitoring systems, especially wave measurement buoys. This is problematic because it limits the direct linkage of wave states to their specific synoptic drivers. To begin to address this shortcoming a buoy was deployed just south of the Bering Strait in late July with anticipated pickup in mid October, 2011. Wave events recorded by buoy, which was sponsored by the Environmental Protection Agency and NOAA, will be examined in terms of the specific synoptic systems responsible. The broader context of how typical these storm systems are will also be overviewed.

  19. Association of synoptic variability in surface turbulent fluxes with cyclone characteristics in the Northern hemisphere midlatitudes

    NASA Astrophysics Data System (ADS)

    Tilinina, Natalia; Gulev, Sergey

    2015-04-01

    Surface turbulent heat fluxes are primarily responsible for variability of surface ocean heat budget on synoptic and interannual scales. On synoptic time scale they are highly variable in time ranging from hundreds to thousands W/m2. This variability is primarily driven by variations of near surface atmospheric characteristics controlled in midlatitudes by atmospheric cyclones. We focus on understanding the mechanisms of synoptic variability of surface turbulent fluxes and particularly on the origins of extreme turbulent fluxes and their further impact on the atmospheric and oceanic dynamics. The main questions addressed in this study are (i) what are the large scale atmospheric conditions associated with extreme ocean surface fluxes and to what extent they are related to cyclones, (ii) what is the role of extreme surface fluxes in the variability of oceanic heat content, and (iii) which characteristics of atmospheric cyclones are most sensitive to the surface ocean flux signals? To answer these questions, we analyse statistical characteristics of surface turbulent heat fluxes and cyclone characteristics over the midlatitudinal North Atlantic and North Pacific. Further we investigate links of cyclones and surface fluxes with each other focusing on cyclone life cycle characteristics such as deepening rates, propagation velocities, life time and clustering. We derived characteristics of the extreme surface fluxes from the empirical probability distributions of surface fluxes from the NCEP-CFSR reanalysis for the period 1979-onwards. Cyclone tracking for the same period has been performed using state of the art numerical tracking algorithm applied to the reanalysis SLP at 6-hourly resolution. We argue that the presence of the high pressure system following to the rare part of propagating cyclone is a critical condition for the formation of extreme surface ocean fluxes which are associated with the cyclone-anticyclone interaction zone rather than with cyclone per se

  20. On the dynamics of synoptic scale cyclones associated with flood events in Crete

    NASA Astrophysics Data System (ADS)

    Flocas, Helena; Katavoutas, George; Tsanis, Ioannis; Iordanidou, Vasiliki

    2015-04-01

    Flood events in the Mediterranean are frequently linked to synoptic scale cyclones, although topographical or anthropogenic factors can play important role. The knowledge of the vertical profile and dynamics of these cyclones can serve as a reliable early flood warning system that can further help in hazard mitigation and risk management planning. Crete is the second largest island in the eastern Mediterranean region, being characterized by high precipitation amounts during winter, frequently causing flood events. The objective of this study is to examine the dynamic and thermodynamic mechanisms at the upper and lower levels responsible for the generation of these events, according to their origin domain. The flooding events were recorded for a period of almost 20 years. The surface cyclones are identified with the aid of MS scheme that was appropriately modified and extensively employed in the Mediterranean region in previous studies. Then, the software VTS, specially developed for the Mediterranean cyclones, was employed to investigate the vertical extension, slope and dynamic/kinematic characteristics of the surface cyclones. Composite maps of dynamic/thermodynamic parameters, such as potential vorticity, temperature advection, divergence, surface fluxes were then constructed before and during the time of the flood. The dataset includes 6-hourly surface and isobaric analyses on a 0.5° x 0.5° regular latitude-longitude grid, as derived from the ERA-INTERIM Reanalysis of the ECMWF. It was found that cyclones associated with flood events in Crete mainly generate over northern Africa or southern eastern Mediterranean region and experience their minimum pressure over Crete or southwestern Greece. About 84% of the cyclones extend up to 500hPa, demonstrating that they are well vertically well-organized systems. The vast majority (almost 84%) of the surface cyclones attains their minimum pressure when their 500 hpa counterparts are located in the NW or SW, confirming

  1. Parameters affecting seat belt use in Greece.

    PubMed

    Yannis, G; Laiou, A; Vardaki, S; Papadimitriou, E; Dragomanovits, A; Kanellaidis, G

    2011-09-01

    The objective of this research is the exploration of seat belt use in Greece and particularly the identification of the parameters affecting seat belt use in Greece. A national field survey was conducted for the analytical recording of seat belt use. A binary logistic regression model was developed, and the impact of each parameter on seat belt use in Greece was quantified. Parameters included in the model concern characteristics of car occupants (gender, age and position in the car), the type of the car and the type of the road network. The data collection revealed that in Greece, the non-use of seat belt on the urban road network was higher than on the national and rural road network and young and older men use seat belts the least. The developed model showed that travelling on a national road is negative for not wearing the seat belt. Finally, the variable with the highest impact on not wearing a seat belt is being a passenger on the back seats. PMID:21452095

  2. Survey of Beta nana in Greece

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The wild species Beta nana is a crop wild relative of cultivated beets and a potential genetic resource for beet breeding. It is a rare but currently not threatened alpine species endemic to Greece which may be prone to extinction risk from climate warming in future. A plant exploration was conducte...

  3. Women of Ancient Greece: Participating in Sport?

    ERIC Educational Resources Information Center

    Mills, Brett D.

    Based on evidence obtained from Greek literature and artifacts, this paper examines the extent to which women in ancient Greece participated in physical activity, sports, and games. Homer's "Odyssey" describes women playing ball and driving chariots; vases dating back to 700-675 B.C. portray women driving light chariots in a procession; a girl…

  4. The Preparation of School Psychologists in Greece

    ERIC Educational Resources Information Center

    Hatzichristou, Chryse; Polychroni, Fotini

    2014-01-01

    The paper describes the preparation of school psychologists in Greece. It discusses the social and cultural contexts that have influenced the evolution of the discipline of psychology, the beginning of training programs in school psychology, and the current status of school psychological services. The structure of the Graduate Program of School…

  5. Higher Education in Greece Compared to Canada

    ERIC Educational Resources Information Center

    Miliotis, Helen

    2014-01-01

    This paper compares and contrasts higher education in Canada and Greece. An overview of the systems in place is followed by an analysis centred on the triad of funding, access and quality. Similarities and differences are highlighted, and the current challenges and issues faced by both nations will be examined, especially in terms of world…

  6. Estimating instream constituent loads using replicate synoptic sampling, Peru Creek, Colorado

    NASA Astrophysics Data System (ADS)

    Runkel, Robert L.; Walton-Day, Katherine; Kimball, Briant A.; Verplanck, Philip L.; Nimick, David A.

    2013-05-01

    SummaryThe synoptic mass balance approach is often used to evaluate constituent mass loading in streams affected by mine drainage. Spatial profiles of constituent mass load are used to identify sources of contamination and prioritize sites for remedial action. This paper presents a field scale study in which replicate synoptic sampling campaigns are used to quantify the aggregate uncertainty in constituent load that arises from (1) laboratory analyses of constituent and tracer concentrations, (2) field sampling error, and (3) temporal variation in concentration from diel constituent cycles and/or source variation. Consideration of these factors represents an advance in the application of the synoptic mass balance approach by placing error bars on estimates of constituent load and by allowing all sources of uncertainty to be quantified in aggregate; previous applications of the approach have provided only point estimates of constituent load and considered only a subset of the possible errors. Given estimates of aggregate uncertainty, site specific data and expert judgement may be used to qualitatively assess the contributions of individual factors to uncertainty. This assessment can be used to guide the collection of additional data to reduce uncertainty. Further, error bars provided by the replicate approach can aid the investigator in the interpretation of spatial loading profiles and the subsequent identification of constituent source areas within the watershed. The replicate sampling approach is applied to Peru Creek, a stream receiving acidic, metal-rich effluent from the Pennsylvania Mine. Other sources of acidity and metals within the study reach include a wetland area adjacent to the mine and tributary inflow from Cinnamon Gulch. Analysis of data collected under low-flow conditions indicates that concentrations of Al, Cd, Cu, Fe, Mn, Pb, and Zn in Peru Creek exceed aquatic life standards. Constituent loading within the study reach is dominated by effluent

  7. Estimating instream constituent loads using replicate synoptic sampling, Peru Creek, Colorado

    USGS Publications Warehouse

    Runkel, Robert L.; Walton-Day, Katherine; Kimball, Briant A.; Verplanck, Philip L.; Nimick, David A.

    2013-01-01

    The synoptic mass balance approach is often used to evaluate constituent mass loading in streams affected by mine drainage. Spatial profiles of constituent mass load are used to identify sources of contamination and prioritize sites for remedial action. This paper presents a field scale study in which replicate synoptic sampling campaigns are used to quantify the aggregate uncertainty in constituent load that arises from (1) laboratory analyses of constituent and tracer concentrations, (2) field sampling error, and (3) temporal variation in concentration from diel constituent cycles and/or source variation. Consideration of these factors represents an advance in the application of the synoptic mass balance approach by placing error bars on estimates of constituent load and by allowing all sources of uncertainty to be quantified in aggregate; previous applications of the approach have provided only point estimates of constituent load and considered only a subset of the possible errors. Given estimates of aggregate uncertainty, site specific data and expert judgement may be used to qualitatively assess the contributions of individual factors to uncertainty. This assessment can be used to guide the collection of additional data to reduce uncertainty. Further, error bars provided by the replicate approach can aid the investigator in the interpretation of spatial loading profiles and the subsequent identification of constituent source areas within the watershed. The replicate sampling approach is applied to Peru Creek, a stream receiving acidic, metal-rich effluent from the Pennsylvania Mine. Other sources of acidity and metals within the study reach include a wetland area adjacent to the mine and tributary inflow from Cinnamon Gulch. Analysis of data collected under low-flow conditions indicates that concentrations of Al, Cd, Cu, Fe, Mn, Pb, and Zn in Peru Creek exceed aquatic life standards. Constituent loading within the study reach is dominated by effluent from the

  8. THE M 33 SYNOPTIC STELLAR SURVEY. I. CEPHEID VARIABLES

    SciTech Connect

    Pellerin, Anne; Macri, Lucas M. E-mail: lmacri@physics.tamu.edu

    2011-04-01

    We have conducted a ground-based BVI synoptic survey of the Local Group galaxy M 33 which covers most of its disk and spans a period of 7 years. The survey targets luminous, long-period variables such as Cepheids and Miras and combines images from the DIRECT project and follow-up observations at the WIYN 3.5 m telescope. This paper, the first in a series, presents the discovery and characterization of 564 Cepheid variables, which represent a factor of two increase over previous samples with calibrated point-spread function (PSF) photometry. We also describe the details of the observations and analysis of the survey data, including the use of archival Hubble Space Telescope images to characterize biases in our ground-based PSF photometry.

  9. Interannual to Synoptic Scale Variability in Intercontinental Transport

    NASA Astrophysics Data System (ADS)

    Gupta, M. L.; Nielsen, J. E.; Douglass, A. R.; Kawa, S. R.; Pawson, S.

    2004-05-01

    Intercontinental transport (ICT) represents pathways of atmospheric flow responsible for dispersion of air pollutants e.g. ozone and aerosols that play vital roles in regional air quality and climate change. Temporal variations in atmospheric dynamics influence behavior of ICT. Here, we investigate interannual to synoptic scale variability in ICT using a source-receptor relationship. We performed a 10-year `online' simulation of eight Rn-like tracers (one global and seven regional) using Finite Volume General Circulation Model. Six-hourly model output archived from this simulation is analyzed for surface concentration, vertical profile and column amount of all tracers on various timescales at 50 regional receptors placed around the globe. We quantified the contributions from the seven source regions to global tracer distribution at these receptors. In addition, we will present a statistical description of tracer distributions and regional contributions representing the 10-year simulation period.

  10. New Synoptic Maps of the Solar Corona from UVCS Observations

    NASA Astrophysics Data System (ADS)

    Strachan, L.; Panasyuk, A. V.; Miralles, M.; Kohl, J. L.; Baham, M.

    2005-05-01

    We present for the first time synoptic maps of the extended solar corona (r/Ro > 1.5) based on eight years of data from the SOHO Ultraviolet Coronagraph Spectrometer (UVCS). The data reveal the changes in the physical properties of the large scale features in the corona. Maps of O VI line intensities, line widths, and line ratios for the O VI 1032/1037 doublet and intensities and line widths for the H I Ly-alpha line reveal information about the evolution of coronal densities, temperatures, and outflow velocities over the solar cycle. In particular these data are used in support of program to understand the solar cycle variation of coronal holes and coronal streamers. This work is supported by NASA Grant NAG5-12781 to the Smithsonian Astrophysical Observatory and NASA subcontract OGSP21010200061SAO awarded to SAO through a grant to Southern Universty at Baton Rouge.

  11. Stratospheric warmings: Synoptic, dynamic and general-circulation aspects

    NASA Technical Reports Server (NTRS)

    Mcinturff, R. M. (Editor)

    1978-01-01

    Synoptic descriptions consist largely of case studies, which involve a distinction between major and minor warmings. Results of energetics studies show the importance of tropospheric-stratospheric interaction, and the significance of the pressure-work term near the tropopause. Theoretical studies have suggested the role of wave-zonal flow interaction as well as nonlinear interaction between eddies, chemical and photochemical reactions, boundary forcing, and other factors. Numerical models have been based on such considerations, and these are discussed under various categories. Some indication is given as to why some of the models have been more successful than others in simulating warnings. The question of ozone and its role in warmings is briefly discussed. Finally, a broad view is taken of stratospheric warmings in relation to man's activities.

  12. Synoptic radio observations as proxies for upper atmospheric modelling

    NASA Astrophysics Data System (ADS)

    Dudok de Wit, T.; Bruinsma, S.; Shibasaki, K.

    2013-12-01

    The solar radio flux at 10.7 cm is one of the most widely used solar proxies for upper atmospheric modelling. In comparison, very little attention has been given to the flux at other centimetric wavelengths, which provides important complimentary information on the solar radiative output. Synoptic radio observations have been made almost continuously since the late 1950's by several observatories, and in particular at Toyokawa and Nobeyama. We have merged different observations into a single continuous composite dataset of daily radio fluxes at 30, 15, 10.7 and 8 cm (without flares), ranging from 1957 up to today. A blind source separation analysis shows that the variability on time scales from days to several months can be decomposed into two contributions, which can be readily identified as thermal Bremsstrahlung and gyro-resonance emission. Most solar indices, such as the MgII index and the H Lyman-alpha line intensity, can be remarkably well reconstructed by linear combination of these two contributions. We advocate the flux at 30 cm for upper atmospheric modelling since it performs better than the 10.7 cm flux when it comes to describing the solar forcing of the thermospheric density; this is revealed by comparing neutral density observations with reconstructions from the DTM (Drag Temperature Model) model. These results show that synoptic radio observations greatly add to the spectral variation that is available in the 10.7 cm flux. Because of their long-term stability and their reliability, they are also excellent candidates for operational space weather use.

  13. The Palomar-Quest Digital Synoptic Sky Survey: Summary and Initial Results

    NASA Astrophysics Data System (ADS)

    Djorgovski, Stanislav G.; Baltay, C.; Mahabal, A.; Rabinowitz, D.; Drake, A.; Donalek, C.; Glikman, E.; Graham, M.; Williams, R.; Ellman, N.; Scalzo, R.; Bauer, A.; Nugent, P.; PQ Survey Team

    2009-05-01

    The Palomar-Quest (PQ) digital synoptic sky survey was conducted over a period of 5 years, ending in September 2008. The survey is a joint venture between groups at Yale and Caltech, with collaborating groups world-wide. The data were obtained using the Palomar 48-inch Samuel Oschin telescope and QUEST-2 112 CCD camera, with up to 4 distinct filters (Johnson UBRI or Gunn griz systems). Data were taken in the drift scan mode, in 4.6 deg wide strips of a constant declination, typically with 2 passes per night. The survey covered a total area of 15,500 deg2, with up to several tens of passes per location, and with the time baselines ranging from minutes to years. About 15 TB or raw data were collected in the course of about 550 nights (including non-photometric conditions). In addition, a somewhat larger amount of data over a larger number of nights have been taken in the point-and-stare mode, in a single broad-band red filter. The data have been processed using independent pipelines at Yale, Caltech, and LBNL. The survey was fully VO-compliant, and served as a testbed for development of a number of VO-related standards and technologies. All of the data are now in the process of being reprocessed and recalibrated, and will be made fully publicly available. Given the synoptic nature of the survey, most of the initial scientific studies involve exploration of various time-domain phenomena, such as Supernovae, variability of AGN, and high-amplitude variable stars. We have also conducted searches for high-redshift quasars, gravitational lenses, and other projects. We will describe some of the results to date.

  14. Coastal erosion and accretion rates in Greece

    NASA Astrophysics Data System (ADS)

    Foteinis, Spyros; Papadopoulos, Costas; Koutsogiannaki, Irini; Synolakis, Costas

    2010-05-01

    Erosion threatens many coastal regions of Greece. Anthropogenic changes of landforms such as coastal roads built on even narrow beaches, sand mining for construction, poor design of coastal structures that interfere with sediment, and dams without sediment bypasses have significantly reduced beach widths. We present erosion rates for different beaches, some of which are in sensitive ecosystems, otherwise "protected" by local and EU ordinances. By comparing inferences of beach widths in varying intervals from 1933 to 2006, we infer that the construction of dams in Acheloos river in western Greece, built in a faraonic attempt to partially divert its flows to eastern Greece, this is responsible for up to 20m/year erosion rates observed in certain locales in the Acheloos delta. More characteristic erosion rates in the region are ~ 2m/year. By contrast, there appears rapid accretion of up to 4m/year in the beaches around the Nestos delta in northern Greece (Papadopoulos, 2009). In beaches that are not near large river deltas, erosion rates range from 0.5m/year to 1m/year. While we have not done comprehensive comparisons among coastlines with different levels of coastal development, it does appear that rapid coastal development correlates well with erosion rates. The underlying problem is the complete lack of any semblance of coastal zone management in Greece and substandard design of coastal structures, which are often sited without any measurements of waves and currents offshore (Synolakis et al, 2008). Beach maintenance remains an exotic concept for most local authorities, who invariably prefer to build hard coastal structures to "protect" versus nourish, siting lack of experience with nourishment and "environmental" concerns. In certain cases, choices are dictated by costs, the larger the cost the easier the project gets approved by regulatory authorities, hence the preference for concrete or rubble structures. We conclude that, unless urgent salvage measures are

  15. Tsunami disaster risk management capabilities in Greece

    NASA Astrophysics Data System (ADS)

    Marios Karagiannis, Georgios; Synolakis, Costas

    2015-04-01

    Greece is vulnerable to tsunamis, due to the length of the coastline, its islands and its geographical proximity to the Hellenic Arc, an active subduction zone. Historically, about 10% of all world tsunamis occur in the Mediterranean region. Here we review existing tsunami disaster risk management capabilities in Greece. We analyze capabilities across the disaster management continuum, including prevention, preparedness, response and recovery. Specifically, we focus on issues like legal requirements, stakeholders, hazard mitigation practices, emergency operations plans, public awareness and education, community-based approaches and early-warning systems. Our research is based on a review of existing literature and official documentation, on previous projects, as well as on interviews with civil protection officials in Greece. In terms of tsunami disaster prevention and hazard mitigation, the lack of tsunami inundation maps, except for some areas in Crete, makes it quite difficult to get public support for hazard mitigation practices. Urban and spatial planning tools in Greece allow the planner to take into account hazards and establish buffer zones near hazard areas. However, the application of such ordinances at the local and regional levels is often difficult. Eminent domain is not supported by law and there are no regulatory provisions regarding tax abatement as a disaster prevention tool. Building codes require buildings and other structures to withstand lateral dynamic earthquake loads, but there are no provisions for resistance to impact loading from water born debris Public education about tsunamis has increased during the last half-decade but remains sporadic. In terms of disaster preparedness, Greece does have a National Tsunami Warning Center (NTWC) and is a Member of UNESCO's Tsunami Program for North-eastern Atlantic, the Mediterranean and connected seas (NEAM) region. Several exercises have been organized in the framework of the NEAM Tsunami Warning

  16. Synoptic variability of extreme snowfall in the St. Elias Mountains, Yukon, Canada

    NASA Astrophysics Data System (ADS)

    Andin, Caroline; Zdanowicz, Christian; Copland, Luke

    2015-04-01

    -stretched Aleutian Low (AL) having an easternmost node near the Kenai Peninsula, conditions that drove a strong southwesterly upper airstream across the Gulf of Alaska towards the coast. Situations with a single-node, westerly-shifted AL were comparatively rare. The spatial configuration of the synoptic AL pressure pattern appears to play a greater role in determining snowfall amount in the central St. Elias Mountains than do pressure anomalies within the AL. The estimated snowfall gradient from coastal Alaska to the central St. Elias Mountains during intense snowfall events averaged +2.0 ± 0.7 mm/km (SWE), while the continental-side gradient from the mountains towards the Yukon plateau averaged -3.3 ± 0.9 mm/km (SWE). The findings presented here can better constrain the climatic interpretation of long proxy records of snow accumulation variations developed from glacier cores drilled in the St. Elias Mountains or nearby regions.

  17. 69 FR 11040 - Electrolytic Manganese Dioxide From Australia, Greece, Ireland, Japan, and South Africa

    Federal Register 2010, 2011, 2012, 2013, 2014

    2004-03-09

    ... COMMISSION Electrolytic Manganese Dioxide From Australia, Greece, Ireland, Japan, and South Africa AGENCY... terminating its antidumping investigations on electrolytic manganese dioxide from Australia, Greece, Ireland... dioxide from Australia, Greece, Ireland, Japan, and South Africa (investigations Nos. 731-TA-1048 and...

  18. 61 FR 13917 - Hellenikon International Airport, Athens, Greece; Notification of Ineffective Security Measures

    Federal Register 2010, 2011, 2012, 2013, 2014

    1996-03-28

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF TRANSPORTATION Office of the Secretary Hellenikon International Airport, Athens, Greece; Notification of Ineffective... Republic of Greece that I had determined that Hellenikon International Airport, Athens, Greece, did...

  19. The EUROSEISTEST Experimental Test Site in Greece

    NASA Astrophysics Data System (ADS)

    Pitilakis, K.; Manos, G.; Raptakis, D.; Anastasiadis, A.; Makra, K.; Manakou, M.

    2009-04-01

    The European experimental site EUROSEISTEST has been established since 1993 in the epicentral area of the June 20th 1978 earthquake (40.8˚ N, 23.2˚ E, Ms 6.5, Imax VIII+ MSK, Papazachos et al., 1979), located in the active tectonic Mygdonian basin, 30km NNE from Thessaloniki, Greece. Euroseistest has been funded by the European Commission - Directorate General for Research and Development under the framework of consecutive EC research projects (EuroseisTest, EuroseisMod and Eurroseisrisk). It is specially designed and dedicated to conduct experimental and theoretical studies on site effects, soil and site characterization and soil-foundation-structure interaction phenomena. The geological, geophysical and geotechnical conditions of the Euroseistest valley (Mygdonian graben) is very well constrained through numerous in situ campaigns and laboratory tests. The permanent accelerometric network comprises 21 digital 3D stations, including vertical arrays down to 200m (schist bedrock), covering a surface of about 100 sq Km. The site is also covered by a permanent seismological network. A number of high quality recordings, from temporary and permanent arrays, gave the possibility to perform advanced experimental and theoretical studies on site effects (e.g. Raptakis et al., 1998; Pitilakis et al., 1999; Raptakis et al., 2000; Chávez-García et al., 2000; Makra, 2000; Makra et al., 2001 & 2005). The main advantage of Euroseistest is the detailed knowledge of the 3D geological-geotechnical structure of the basin (Manakou, 2007) and its dense permanent accelerometric network. For this reason the site has been recently selected by CEA to validate and check the advanced numerical codes to be used in Cadarache ITER project. Besides the study of site effects, Euroseistest offers interesting possibilities to study SSI problems through two model structures (scaled 1:3). A 6-storey building and a bridge pier, which have been constructed and instrumented in the centre of the

  20. The wind energy potential of western Greece

    SciTech Connect

    Katsoulis, B.D.; Metaxas, D.A. )

    1992-12-01

    In this study wind data were used to determine the monthly and annual variations of the wind at 13 meterological stations in western Greece. An analysis of the available wind data for the Ionian Sea islands and the western coasts of Greece is carried out to ascertain its potential for wind energy development. The effect of the limited number of daily observations available on the accuracy of the mean wind speed and annual wind energy estimates is ascertained. The wind speed and direction distributions are represented with Weibull functions. Besides, a mass-consistent numerical mesoscale model was used to give an overview of the wind prospecting and siting problem, and an example of its use for Corfu (Kerkira), an island in the Ionian Sea, is given. The comparison of the accuracy of the stimulation results versus measured wind at an available site is quite encouraging even though it cannot be conclusive since only one station is available.

  1. Extreme precipitation events in NW Greece

    NASA Astrophysics Data System (ADS)

    Houssos, E. E.; Bartzokas, A.

    2006-02-01

    In this work, the extreme precipitation events in NW Greece are studied. The data used are daily precipitation totals recorded at the meteorological station of Ioannina University for the period 1970-2002. 156 days with precipitation totals above 35 mm (5% upper limit) are only considered. It is seen that, a minimum frequency of extreme precipitation events appears in the period 1986-1991, which is characterized by a high positive NAO index. For each of the 156 extreme precipitation days, at first, the mean sea level pressure pattern over Europe is constructed by using 273 grid point values. Using Factor Analysis, the dimensionality of the 156×273 data matrix is reduced to 156×5 (84% of the total variance) and then, Cluster Analysis is applied on the results of Factor Analysis. Thus, the 156 cases are grouped objectively to 11 clusters, revealing the main pressure patterns, which favour extreme precipitation in NW Greece. Seven of the patterns are encountered in winter and autumn, while three of them cover a period from autumn to spring and one appears mainly in summer. In all of them the cause of the extreme precipitation event is a low pressure system centred west of Greece or a low pressure trough extended eastwards or southwards up to Greece. In some cases the depression is so strong and extended that it covers the whole Europe and the Mediterranean. In the single summer pattern, rainfall is caused by an extension of the SW Asia thermal low up to the central Mediterranean.

  2. Anthropogenic Erosion in Aghios Nikolaos, Greece

    NASA Astrophysics Data System (ADS)

    Foteinis, Spyros; Skanavis, Vassilis; Maravelakis, Nikos; Kalligeris, Nikos; Sartzetakis, George; Voukouvalas, Vangelis; Koutsongiannaki, Irini; Synolakis, Costas

    2013-04-01

    The beaches of Greece has been eroding rapidly in the past three decades, at rates, that in some cases, reach 1m/year. We report measurements from Agios Nicolaos, Crete based on beach profiles, historic aerial photos, satellite imagery and eyewitness report. We discuss the findings in the context of antropogenic factors. We correlate our measurements, qualitatively, with different indices and produce a risk map to allow decision makers to prioritize mitigation policies.

  3. Epidemiology of cutaneous leishmaniasis in Greece.

    PubMed

    Stratigos, J; Tosca, A; Nicolis, G; Papavasiliou, S; Capetanakis, J

    1980-03-01

    Cutaneous leishmaniasis is a disease endemic in Greece. Cases collected between the years 1975 and 1979 are analyzed from a clinico-epidemiologic point of view. Prevalence is highest in the Ionian islands and Crete. The disease most commonly affects individuals 10 to 20 years of age. The exposed parts of the body are most commonly involved, particularly the face. The period of highest incidence is mid-winter. PMID:7358449

  4. A near-synoptic survey of the Southwest Indian Ocean

    NASA Astrophysics Data System (ADS)

    Donohue, Kathleen A.; Toole, John M.

    2003-07-01

    This study focused on the southwest region of the Indian Ocean, where the poleward-directed Agulhas Current is born, and where dense waters filter through fractures in the Southwest Indian Ridge to form an equatorward-directed deep boundary current east of Madagascar. Both represent major circulation features of the Indian Ocean: the Agulhas in its role as a western-boundary current closes the wind-driven subtropical gyre; the deep western-boundary current renews the bottom waters of the Madagascar, Mascarene, and Somali basins to the north. A regional, quasi-synoptic survey of the Southwest Indian Ocean carried out as part of the World Ocean Circulation Experiment Hydrographic Program from May through July of 1995 occupied a cruise track that comprised a closed "box" in the Southwest Indian Ocean. Full-depth water properties and direct-velocity measurements were used to diagnose the circulation patterns as a function of depth and to estimate the transports of the major currents. The synoptic circulation was quantified by the construction of a referenced geostrophic velocity field. Water-mass distributions, direct-velocity measurements, and mass conservation within bounded regions guided the placement of the level of no motion. Errors in the reference scheme and from synoptic-scale circulation features such as eddies and internal waves that are aliased by the hydrographic sampling led to uncertainties in the transport estimates. The upper-ocean Agulhas transport (neutral density, γn<27.96 kg m -3, depths≲2000 m) was estimated to be 76×10 6 m 3 s -1. Contributions to the Agulhas consisted of 29×10 6 m 3 s -1 from the westward limb of the subtropical gyre south of 25°S, 20×10 6 m 3 s -1 from the poleward flow east of Madagascar, which subsequently turns to move west at about 25°S, and an additional poleward flow of 18×10 6 m 3 s -1 through the Mozambique Channel. Bathymetry strongly controls the deep and bottom circulation: the African Coast, the Mozambique

  5. Medical Informatics Education & Research in Greece

    PubMed Central

    Chouvarda, I.

    2015-01-01

    Summary Objectives This paper aims to present an overview of the medical informatics landscape in Greece, to describe the Greek ehealth background and to highlight the main education and research axes in medical informatics, along with activities, achievements and pitfalls. Methods With respect to research and education, formal and informal sources were investigated and information was collected and presented in a qualitative manner, including also quantitative indicators when possible. Results Greece has adopted and applied medical informatics education in various ways, including undergraduate courses in health sciences schools as well as multidisciplinary postgraduate courses. There is a continuous research effort, and large participation in EU-wide initiatives, in all the spectrum of medical informatics research, with notable scientific contributions, although technology maturation is not without barriers. Wide-scale deployment of eHealth is anticipated in the healthcare system in the near future. While ePrescription deployment has been an important step, ICT for integrated care and telehealth have a lot of room for further deployment. Conclusions Greece is a valuable contributor in the European medical informatics arena, and has the potential to offer more as long as the barriers of research and innovation fragmentation are addressed and alleviated. PMID:26123910

  6. Novel phleboviruses detected in ticks, Greece.

    PubMed

    Papa, Anna; Kontana, Anastasia; Tsioka, Katerina; Chaligiannis, Ilias; Sotiraki, Smaragda

    2016-07-01

    Since 2009, when severe fever with thrombocytopenia syndrome virus and Heartland virus have been identified and associated with disease in humans, the interest on tick-borne phleboviruses is increasing rapidly. The aim of the present study was to investigate the presence of tick-borne phleboviruses in Greece and compare them with respective ones detected worldwide. Ticks collected from goats and sheep in 60 sites of 13 regional units of Greece were grouped in pools (1-3 ticks per pool) and tested for the presence of phleboviral RNA. Six of 210 pools were positive; they consisted of Rhipicephalus sanguineus ticks collected from sheep in 3 regional units of Greece: Pella (2/30, 6.7%), Imathia (2/21, 9.5%), and Ioannina (2/28, 7.1%). The overall tick minimum infection rate was 2.1%. The sequences of the Greek phlebovirus (provisionally named Antigone virus) form a distinct clade in the tick-borne phleboviruses, differing by >40% from the currently known phleboviruses. Any probable implication of these viruses to public health remains to be elucidated. PMID:26935112

  7. The effects of implementing synoptic pathology reporting in cancer diagnosis: a systematic review.

    PubMed

    Sluijter, Caro E; van Lonkhuijzen, Luc R C W; van Slooten, Henk-Jan; Nagtegaal, Iris D; Overbeek, Lucy I H

    2016-06-01

    Pathology reporting is evolving from a traditional narrative report to a more structured synoptic report. Narrative reporting can cause misinterpretation due to lack of information and structure. In this systematic review, we evaluate the impact of synoptic reporting on completeness of pathology reports and quality of pathology evaluation for solid tumours. Pubmed, Embase and Cochrane databases were systematically searched to identify studies describing the effect of synoptic reporting implementation on completeness of reporting and quality of pathology evaluation of solid malignant tumours. Thirty-three studies met the inclusion criteria. All studies, except one, reported an increased overall completeness of pathology reports after introduction of synoptic reporting (SR). Most frequently studied cancers were breast (n = 9) and colorectal cancer (n = 16). For breast cancer, narrative reports adequately described 'tumour type' and 'nodal status'. Synoptic reporting resulted in improved description of 'resection margins', 'DCIS size', 'location' and 'presence of calcifications'. For colorectal cancer, narrative reports adequately reported 'tumour type', 'invasion depth', 'lymph node counts' and 'nodal status'. Synoptic reporting resulted in increased reporting of 'circumferential margin', 'resection margin', 'perineural invasion' and 'lymphovascular invasion'. In addition, increased numbers of reported lymph nodes were found in synoptic reports. Narrative reports of other cancer types described the traditional parameters adequately, whereas for 'resection margins' and '(lympho)vascular/perineural invasion', implementation of synoptic reporting was necessary. Synoptic reporting results in improved reporting of clinical relevant data. Demonstration of clinical impact of this improved method of pathology reporting is required for successful introduction and implementation in daily pathology practice. PMID:27097810

  8. Identification and Quantification of Synoptic Structure in Simulated Tiros N Radiance Soundings.

    NASA Astrophysics Data System (ADS)

    White, G. Anderson, III

    There has been continual improvement in the accuracy of retrieved atmospheric soundings from satellite radiance measurements; however, satellite data still provide an overly smooth product which is of limited use for synoptic scale analysis. Considerable smoothing occurs when information present in satellite radiance measurements is lost in the retrieval process. This research describes and develops techniques which (1) identify synoptic features and (2) quantify their fine structures directly from TIROS N satellite radiance data. A series of nine, overlapping, synthetic temperature and moisture soundings is constructed which contains synoptic features representative of the tropical eastern Pacific Ocean. Each of the soundings in the series is perturbed randomly, within limits, to create a statistically meaningful training data set. The training data set is processed through a radiative transfer algorithm to generate equivalent TIROS N satellite observations. The variance of the training set is partitioned into a portion accounting for synoptic class and a portion describing synoptic feature variation within a class. The variance structure of feature quantification differs strongly from that associated with classification. In a two-step process, the training data observations first are separated according to synoptic feature, and, second, the fine structure of the synoptic feature is quantified. Three classification techniques are developed to partition the training data observations into synoptic groups and to classify new soundings: a subjective, graphical, interpretative procedure; canonical discriminant analysis; and, discriminant analysis. Accurate classification was accomplished until atmospheric sounding perturbations exceeded 12% of the observed temperatures of the synoptic class means. Two experiments of feature qualification are described: a prediction of trade wind and frontal inversion height and strength using both synthetic and observed soundings; and

  9. Synoptic- and Mesoscale Weather Situations Associated with Tornadoes in Europe

    NASA Astrophysics Data System (ADS)

    Graf, M.; Sprenger, M.; Moore, R. W.

    2010-09-01

    Tornado research is mainly practiced in and focused on the United States, but tornadoes occur all over the world and cause damage and casualties. In this study, the focus is given to the synoptic- and mesoscale environment which leads to tornadoes in Central Europe. Consideration is given to 15 significant events (defined to be equal to F2 tornadoes) between 2005 and 2006 and in a band north of the Alps and extending from Eastern France to Poland with focus on Germany. Tornado data are taken from the European Severe Weather Database (ESWD), which includes the date, time, location and intensity on the Fujita scale of the event. Three aspects are discussed: (a) The synoptic- and mesoscale weather situation is analysed. The tornado events are characterised with respect to upper-level (jet streaks, PV anomalies) and low-level (fronts) forcings by operational ECMWF analysis data. Moreover, satellite data and surface weather charts of the German Weather Service are taken into account. In many cases, tornadoes took place close to an upper-level PV anomaly (streamer or cut-off). Most events occur under the cyclonic left side (exit and entrance region) of the jet stream. (b) The applicability of US tornado indices is investigated. Consideration is given to typical tornado indices used in the US: convective available potential energy (CAPE), storm-relative helicity (SRH) and the energy helicity index (EHI). It will be shown that the indices are only partly applicable to European settings. On average all indices are significantly lower than in the US. (c) Factors that predetermine the atmosphere for severe convection and tornadoes are discussed. For this reason, regions of moisture source are determined by Lagrangian backward trajectories. In most cases European trajectories start over the Atlantic, whereas US trajectories origin in the Gulf of Mexico. Due to the Alps the moisture transport from the Mediterranean is hindered. Moreover, it can be shown that the destabilization

  10. Los Alamos geostationary orbit synoptic data set: a compilation of energetic particle data

    SciTech Connect

    Baker, D.N.; Higbie, P.R.; Belian, R.D.; Aiello, W.P.; Hones, E.W. Jr.; Tech, E.R.; Halbig, M.F.; Payne, J.B.; Robinson, R.; Kedge, S.

    1981-08-01

    Energetic electron (30 to 2000 keV) and proton (145 keV to 150 MeV) measurements made by Los Alamos National Laboratory sensors at geostationary orbit 6.6 R/sub E/ are summarized. The data are plotted in terms of daily average spectra, 3-h local time averages, and in a variety of statistical formats. The data summarize conditions from mid-1976 through 1978 (S/C 1976-059) and from early 1977 through 1978 (S/C 1977-007). The compilations correspond to measurements at 35/sup 0/W, 70/sup 0/W, and 135/sup 0/W geographic longitude and, thus, are indicative of conditions at 9/sup 0/, 11/sup 0/, and 4.8/sup 0/ geomagnetic latitude, respectively. Most of this report is comprised of data plots that are organized according to Carrington solar rotations so that the data can be easily compared to solar rotation-dependent interplanetary data. As shown in prior studies, variations in solar wind conditions modulate particle intensity within the terrestrial magnetosphere. The effects of these variations are demonstrated and discussed. Potential uses of the Synoptic Data Set by the scientific and applications-oriented communities are also discussed.

  11. Ionospheric absorption, typical ionization, conductivity, and possible synoptic heating parameters in the upper atmosphere

    SciTech Connect

    Walker, J.K.; Bhatnagar, V.P.

    1989-04-01

    Relations for the average energetic particle heating and the typical Hall and Pedersen conductances, as functions of the ground-based Hf radio absorption, are determined. Collis and coworkers used the geosynchronous GEOS 2 particle data to relate or ''calibrate'' the auroral absorption on the same magnetic field lines with five levels of D region ionization. These ionospheric models are related to a Chapman layer that extends these models into the E region. The average energetic particle heating is calculated for each of these models using recent expressions for the effective recombination coefficient. The corresponding height-integrated heating rates are determined and related to the absorption with a quadratic expression. The average Hall and Pedersen conductivities are calculated for each of the nominal absorption ionospheric models. The corresponding height-integrated conductances for nighttime conditions are determined and related to the absorption. Expressions for these conductances during disturbed sunlit conditions are also determined. These relations can be used in conjunction with simultaneous ground-based riometric and magnetic observations to determines the average Hall and Pedersen currents and the Joule heating. The typical daily rate of temperature increase in the mesosphere for storm conditions is several 10 K for both the energetic particle and the Joule heating. The increasing importance of these parameters of the upper and middle atmospheres is discussed. It is proposed that northern hemisphere ionospheric, current, and heating synoptic models and parameters be investigated for use on a regular basis. copyright American Geophysical Union 1989

  12. Prevalence of Secondary Traumatic Stress Among Psychiatric Nurses in Greece.

    PubMed

    Mangoulia, Polyxeni; Koukia, Evmorfia; Alevizopoulos, George; Fildissis, George; Katostaras, Theofanis

    2015-10-01

    The aim of this study was to investigate the prevalence of secondary traumatic stress/compassion fatigue (STS/CF), burnout (BO) and compassion satisfaction (CS) in psychiatric nurses, and their risk factors. The Professional Quality of Life Scale (ProQOL R-IV) and a demographic and work related characteristics questionnaire were distributed to 174 psychiatric nurses in 12 public hospitals in Greece. The majority of participants were at the high risk category for STS/CF (44.8%) and BO (49.4%), while only 8.1% of nurses expressed high potential for CS. Awareness of the factors associated with STS may help nurses to prevent or offset the development of this condition. PMID:26397438

  13. Western Greece unconventional hydrocarbon potential from oil shale and shale gas reservoirs

    NASA Astrophysics Data System (ADS)

    Karakitsios, Vasileios; Agiadi, Konstantina

    2013-04-01

    It is clear that we are gradually running out of new sedimentary basins to explore for conventional oil and gas and that the reserves of conventional oil, which can be produced cheaply, are limited. This is the reason why several major oil companies invest in what are often called unconventional hydrocarbons: mainly oil shales, heavy oil, tar sand and shale gas. In western Greece exist important oil and gas shale reservoirs which must be added to its hydrocarbon potential1,2. Regarding oil shales, Western Greece presents significant underground immature, or close to the early maturation stage, source rocks with black shale composition. These source rock oils may be produced by applying an in-situ conversion process (ICP). A modern technology, yet unproven at a commercial scale, is the thermally conductive in-situ conversion technology, developed by Shell3. Since most of western Greece source rocks are black shales with high organic content, those, which are immature or close to the maturity limit have sufficient thickness and are located below 1500 meters depth, may be converted artificially by in situ pyrolysis. In western Greece, there are several extensive areas with these characteristics, which may be subject of exploitation in the future2. Shale gas reservoirs in Western Greece are quite possibly present in all areas where shales occur below the ground-water level, with significant extent and organic matter content greater than 1%, and during their geological history, were found under conditions corresponding to the gas window (generally at depths over 5,000 to 6,000m). Western Greece contains argillaceous source rocks, found within the gas window, from which shale gas may be produced and consequently these rocks represent exploitable shale gas reservoirs. Considering the inevitable increase in crude oil prices, it is expected that at some point soon Western Greece shales will most probably be targeted. Exploration for conventional petroleum reservoirs

  14. The Large Synoptic Survey Telescope project management control system

    NASA Astrophysics Data System (ADS)

    Kantor, Jeffrey P.

    2012-09-01

    The Large Synoptic Survey Telescope (LSST) program is jointly funded by the NSF, the DOE, and private institutions and donors. From an NSF funding standpoint, the LSST is a Major Research Equipment and Facilities (MREFC) project. The NSF funding process requires proposals and D&D reviews to include activity-based budgets and schedules; documented basis of estimates; risk-based contingency analysis; cost escalation and categorization. "Out-of-the box," the commercial tool Primavera P6 contains approximately 90% of the planning and estimating capability needed to satisfy R&D phase requirements, and it is customizable/configurable for remainder with relatively little effort. We describe the customization/configuration and use of Primavera for the LSST Project Management Control System (PMCS), assess our experience to date, and describe future directions. Examples in this paper are drawn from the LSST Data Management System (DMS), which is one of three main subsystems of the LSST and is funded by the NSF. By astronomy standards the LSST DMS is a large data management project, processing and archiving over 70 petabyes of image data, producing over 20 petabytes of catalogs annually, and generating 2 million transient alerts per night. Over the 6-year construction and commissioning phase, the DM project is estimated to require 600,000 hours of engineering effort. In total, the DMS cost is approximately 60% hardware/system software and 40% labor.

  15. Synoptic IPS and Yohkoh soft X-ray observations

    NASA Technical Reports Server (NTRS)

    Hick, P.; Jackson, B. V.; Rappoport, S.; Woan, G.; Slater, G.; Strong, K.; Uchida, Y.

    1995-01-01

    Interplanetary scintillation measurements of the disturbance factor, g, from October 1991 to October 1992 are used to construct synoptic Carrington maps. These maps, which show the structure of the quiet solar wind, are compared with X-ray Carrington maps from the Yohkoh Soft X-ray Telescope (SXT) instrument. For the period studied the global structure outlined by (weakly) enhanced g-values apparent in the interplanetary scintillation (IPS) maps tend to match the active regions (as shown in the X-ray maps) significantly better than the heliospheric current sheet. Contrary to traditional opinion, which views active regions as magnetically closed structures that do not have any significant impact on the solar wind flow, our results suggest that density fluctuations in the solar wind are significantly enhanced over active regions. These results support the suggestion by Uchida et al. (1992), based on Yohkoh observations of expanding active regions, that active regions play a role in feeding mass into the quiet solar wind.

  16. Synoptic Mid-IR Spectra ToO Novae

    NASA Astrophysics Data System (ADS)

    Helton, L. Andrew; Woodward, Chick; Evans, Nye; Geballe, Tom; Spitzer Nova Team

    2007-02-01

    Stars are the engines of energy production and chemical evolution in our Universe, depositing radiative and mechanical energy into their environments and enriching the ambient ISM with elements synthesized in their interiors and dust grains condensed in their atmospheres. Classical novae (CN) contribute to this cycle of chemical enrichment through explosive nucleosynthesis and the violent ejection of material dredged from the white dwarf progenitor and mixed with the accreted surface layers. We propose to obtain mid-IR spectra of a new galactic CN in outburst to investigate aspects of the CN phenomenon including the in situ formation and mineralogy of nova dust and the elemental abundances resulting from thermonuclear runaway. Synoptic, high S/N Michelle spectra permit: 1) determination of the grain size distribution and mineral composition of nova dust; 2) estimation of chemical abundances of nova ejecta from coronal and other emission line spectroscopy; and 3) measurement of the density and masses of the ejecta. This Gemini `Target of Opportunity' initiative (trigger K=5- 8 mag, assuming adequate PWFS guide stars exist) complements our extensive Spitzer, Chandra, Swift, XMM-Newton CN DDT/ToO programs.

  17. Curvature wavefront sensing for the large synoptic survey telescope.

    PubMed

    Xin, Bo; Claver, Chuck; Liang, Ming; Chandrasekharan, Srinivasan; Angeli, George; Shipsey, Ian

    2015-10-20

    The Large Synoptic Survey Telescope (LSST) will use an active optics system (AOS) to maintain alignment and surface figure on its three large mirrors. Corrective actions fed to the LSST AOS are determined from information derived from four curvature wavefront sensors located at the corners of the focal plane. Each wavefront sensor is a split detector such that the halves are 1 mm on either side of focus. In this paper, we describe the extensions to published curvature wavefront sensing algorithms needed to address challenges presented by the LSST, namely the large central obscuration, the fast f/1.23 beam, off-axis pupil distortions, and vignetting at the sensor locations. We also describe corrections needed for the split sensors and the effects from the angular separation of different stars providing the intrafocal and extrafocal images. Lastly, we present simulations that demonstrate convergence, linearity, and negligible noise when compared to atmospheric effects when the algorithm extensions are applied to the LSST optical system. The algorithm extensions reported here are generic and can easily be adapted to other wide-field optical systems including similar telescopes with large central obscuration and off-axis curvature sensing. PMID:26560396

  18. Curvature wavefront sensing for the large synoptic survey telescope

    NASA Astrophysics Data System (ADS)

    Xin, Bo; Claver, Chuck; Liang, Ming; Chandrasekharan, Srinivasan; Angeli, George; Shipsey, Ian

    2015-10-01

    The Large Synoptic Survey Telescope (LSST) will use an active optics system (AOS) to maintain alignment and surface figure on its three large mirrors. Corrective actions fed to the LSST AOS are determined from information derived from 4 curvature wavefront sensors located at the corners of the focal plane. Each wavefront sensor is a split detector such that the halves are 1mm on either side of focus. In this paper we describe the extensions to published curvature wavefront sensing algorithms needed to address challenges presented by the LSST, namely the large central obscuration, the fast f/1.23 beam, off-axis pupil distortions, and vignetting at the sensor locations. We also describe corrections needed for the split sensors and the effects from the angular separation of different stars providing the intra- and extra-focal images. Lastly, we present simulations that demonstrate convergence, linearity, and negligible noise when compared to atmospheric effects when the algorithm extensions are applied to the LSST optical system. The algorithm extensions reported here are generic and can easily be adapted to other wide-field optical systems including similar telescopes with large central obscuration and off-axis curvature sensing.

  19. H-alpha Off-limb Carrington Synoptic Charts

    NASA Astrophysics Data System (ADS)

    Bertello, L.; Hughes, A.; Pevtsov, A. A.

    2015-12-01

    Observations of solar prominences (and filaments) reveal complex structures, with significant differences inmorphology, lifetime, and complexity of their magnetic field environment. Studies of thesesolar features are important for understanding not only their origin but also their role as precursors ofenergetic events such as flares and coronal mass ejections.The Global Oscillation Network Group (GONG) operated by the National Solar Observatory provides, amongother products, high-cadence broad-band intensity measurements centered in the core ofH-alpha spectral line. Prominences and filaments are quite visible in these 2Kx2K images, that havebeen obtained since 2010. We recentlystarted a project to produce an archive of H-alpha off-limb Carrington Synoptic Charts to be usedfor systematic studies of prominences. Charts are produced to show both spatial and temporal variabilityof these features in four radius zones covering 1.01 to 1.11 solar radii. Here we describe the applied methodologyand show some preliminary results. Potential applications of interest to the solar and heliospheric communitiesare also briefly discussed.

  20. South Hemispheric Teleconnection to Eastern Mediterranean synoptic systems

    NASA Astrophysics Data System (ADS)

    Osetinsky, I.; Alpert, P.

    2009-04-01

    The teleconnections between the Eastern Mediterranean regional climate and large-scaled tropical and midlatitudinal global indices are becoming widely recognized due to the recent publications. We will present the unexpectedly high correlations between the Eastern Mediterranean synoptic system of the Red Sea Trough and global and hemispheric temperature indices. The Red Sea Trough is the pressure pattern originated from the Sudanese Low and stretched over the warm surface of the Red Sea northward, sometimes reaching up to the Western Turkey. We calculated the correlations between the annual number of the Red Sea Trough days over the Eastern Mediterranean region (RST thereafter), and anomalies of the global and northern and southern hemispheric annual temperatures (TG, TNH, TSH, respectively), for 1948-2000. The annual data, both for the RST and for temperatures, were taken unsmoothed. We got the following remarkable correlations: 0.61 between the RST and TG, 0.51 - between RST and TNH, and 0.65 - between RST and TSH. The lower correlation for the Northern Hemisphere (NH), as compared to the Southern Hemisphere (SH), may be explained considering a distribution of continents and oceans. This carries, on the one hand side, a higher NH than SH mankind activity influencing the natural connections, and on the other - an enhanced SH than NH atmospheric circulation.

  1. Synoptic scale wind field properties from the SEASAT SASS

    NASA Technical Reports Server (NTRS)

    Pierson, W. J., Jr.; Sylvester, W. B.; Salfi, R. E.

    1984-01-01

    Dealiased SEASAT SEASAT A Scatterometer System SASS vector winds obtained during the Gulf Of Alaska SEASAT Experiment GOASEX program are processed to obtain superobservations centered on a one degree by one degree grid. The grid. The results provide values for the combined effects of mesoscale variability and communication noise on the individual SASS winds. These superobservations winds are then processed further to obtain estimates of synoptic scale vector winds stress fields, the horizontal divergence of the wind, the curl of the wind stress and the vertical velocity at 200 m above the sea surface, each with appropriate standard deviations of the estimates for each grid point value. They also explain the concentration of water vapor, liquid water and precipitation found by means of the SMMR Scanning Multichannel Microwave Radiometer at fronts and occlusions in terms of strong warm, moist air advection in the warm air sector accompanied by convergence in the friction layer. Their quality is far superior to that of analyses based on conventional data, which are shown to yield many inconsistencies.

  2. Synoptic data for solar-terrestrial physics: The U.K. contribution to long-term monitoring

    NASA Astrophysics Data System (ADS)

    Willis, D. M.; Hewish, A.; Rishbeth, H.; Rycroft, M. J.

    1994-05-01

    In 1989 the Council of the Royal Society of London established a Study Group to investigate the current status and future requirements of solar-terrestrial monitoring in the United Kingdom. This paper summarizes the conclusions and recommendations of the U.K. Study Group. The rationale for regular synoptic monitoring of the solar terrestrial environment is reviewed briefly. Instruments used for solar-terrestrial monitoring in U.K.-supported research programs are listed, with special emphasis on research instruments that produce monitoring data. Some important applications of solar-terrestrial monitoring are outlined and criteria are presented for determining the priorities of various monitoring operations. High priority is attached to monitoring operations that are important for: (1) deriving geophysical models and reference systems; (2) calculating the principal solar-geophysical indices; (3) producing long time series of good data, especially at sites of particular geophysical interest; (4) detecting global changes; (5) contributing to real-time forecasts of solar-terrestrial conditions, or to longer-term predictions and planning; and (6) providing background data for other observations and experiments. The existing U.K. programs of solar-terrestrial monitoring make a highly prestigious contribution to national and international scientific activity. Synoptic measurements of the solar-terrestrial environment are crucial for underpinning present and future programs of basic, strategic and applied research. Therefore, a core program of synoptic monitoring must be maintained in the U.K. It is recommended that this core program should be financed centrally through the Research Councils and reviewed quinquennially.

  3. The impact of economic austerity and prosperity events on suicide in Greece: a 30-year interrupted time-series analysis

    PubMed Central

    Branas, Charles C; Kastanaki, Anastasia E; Michalodimitrakis, Manolis; Tzougas, John; Kranioti, Elena F; Theodorakis, Pavlos N; Carr, Brendan G; Wiebe, Douglas J

    2015-01-01

    Objectives To complete a 30-year interrupted time-series analysis of the impact of austerity-related and prosperity-related events on the occurrence of suicide across Greece. Setting Greece from 1 January 1983 to 31 December 2012. Participants A total of 11 505 suicides, 9079 by men and 2426 by women, occurring in Greece over the study period. Primary and secondary outcomes National data from the Hellenic Statistical Authority assembled as 360 monthly counts of: all suicides, male suicides, female suicides and all suicides plus potentially misclassified suicides. Results In 30 years, the highest months of suicide in Greece occurred in 2012. The passage of new austerity measures in June 2011 marked the beginning of significant, abrupt and sustained increases in total suicides (+35.7%, p<0.001) and male suicides (+18.5%, p<0.01). Sensitivity analyses that figured in undercounting of suicides also found a significant, abrupt and sustained increase in June 2011 (+20.5%, p<0.001). Suicides by men in Greece also underwent a significant, abrupt and sustained increase in October 2008 when the Greek recession began (+13.1%, p<0.01), and an abrupt but temporary increase in April 2012 following a public suicide committed in response to austerity conditions (+29.7%, p<0.05). Suicides by women in Greece also underwent an abrupt and sustained increase in May 2011 following austerity-related events (+35.8%, p<0.05). One prosperity-related event, the January 2002 launch of the Euro in Greece, marked an abrupt but temporary decrease in male suicides (−27.1%, p<0.05). Conclusions This is the first multidecade, national analysis of suicide in Greece using monthly data. Select austerity-related events in Greece corresponded to statistically significant increases for suicides overall, as well as for suicides among men and women. The consideration of future austerity measures should give greater weight to the unintended mental health consequences that may follow and the public

  4. Evaluation of the synoptic and mesoscale predictive capabilities of a mesoscale atmospheric simulation system

    NASA Technical Reports Server (NTRS)

    Koch, S. E.; Skillman, W. C.; Kocin, P. J.; Wetzel, P. J.; Brill, K.; Keyser, D. A.; Mccumber, M. C.

    1983-01-01

    The overall performance characteristics of a limited area, hydrostatic, fine (52 km) mesh, primitive equation, numerical weather prediction model are determined in anticipation of satellite data assimilations with the model. The synoptic and mesoscale predictive capabilities of version 2.0 of this model, the Mesoscale Atmospheric Simulation System (MASS 2.0), were evaluated. The two part study is based on a sample of approximately thirty 12h and 24h forecasts of atmospheric flow patterns during spring and early summer. The synoptic scale evaluation results benchmark the performance of MASS 2.0 against that of an operational, synoptic scale weather prediction model, the Limited area Fine Mesh (LFM). The large sample allows for the calculation of statistically significant measures of forecast accuracy and the determination of systematic model errors. The synoptic scale benchmark is required before unsmoothed mesoscale forecast fields can be seriously considered.

  5. Synoptic patterns of atmospheric circulation associated with intense precipitation events over the Brazilian Amazon

    NASA Astrophysics Data System (ADS)

    Santos, Eliane Barbosa; Lucio, Paulo Sérgio; Santos e Silva, Cláudio Moisés

    2015-12-01

    The objective of this study is to characterize the atmospheric patterns associated with the occurrence of intense precipitation events (IPE) in different sub-regions of the Brazilian Amazon. Intense rainfall cases over six sub-regions were selected from a precipitation data set for the period from 1983 to 2012. The composition technique was used to characterize the prevailing atmospheric patterns for the occurrence of IPE. In the south of the Amazon, the composition fields showed a favorable configuration for the formation of the South Atlantic Convergence Zone (SACZ). Along the coast, the intense precipitation events must be associated with mesoscale systems, such as squall lines. In the northwest, they are apparently associated with the Intertropical Convergence Zone (ITCZ) and/or local convection. The results reveal the complexity of the synoptic environment associated with the formation and development of weather systems that produce heavy rainfall in the Amazon Basin. Several factors can interfere as conditions in large-scale, local conditions and thermodynamic factors.

  6. Solar system exploration from the Moon: Synoptic and comparative study of bodies in our Planetary system

    NASA Astrophysics Data System (ADS)

    Bruston, P.; Mumma, M. J.

    1994-06-01

    An observational approach to Planetary Sciences and exploration from Earth applies to a quite limited number of targets, but most of these are spatially complex, and exhibit variability and evolution on a number of temporal scales which lie within the scope of possible observations. Advancing our understanding of the underlying physics requires the study of interactions between the various elements of such systems, and also requires study of the comparative response of both a given object to various conditions and of comparable objects to similar conditions. These studies are best conducted in 'campaigns', i.e. comprehensive programs combining simultaneous coherent observations of every interacting piece of the puzzle. The requirements include both imaging and spectroscopy over a wide spectral range, from UV to IR. While temporal simultaneity of operation in various modes is a key feature, these observations are also conducted over extended periods of time. The moon is a prime site offering long unbroken observation times and high positional stability, observations at small angular separation from the sun, comparative studies of planet Earth, and valuable technical advantages. A lunar observatory should become a central piece of any coherent set of planetary missions, supplying in-situ explorations with the synoptic and comparative data necessary for proper advance planning, correlative observations during the active exploratory phase, and follow-up studies of the target body or of related objects.

  7. Solar system exploration from the Moon: Synoptic and comparative study of bodies in our Planetary system

    NASA Technical Reports Server (NTRS)

    Bruston, P.; Mumma, M. J.

    1994-01-01

    An observational approach to Planetary Sciences and exploration from Earth applies to a quite limited number of targets, but most of these are spatially complex, and exhibit variability and evolution on a number of temporal scales which lie within the scope of possible observations. Advancing our understanding of the underlying physics requires the study of interactions between the various elements of such systems, and also requires study of the comparative response of both a given object to various conditions and of comparable objects to similar conditions. These studies are best conducted in 'campaigns', i.e. comprehensive programs combining simultaneous coherent observations of every interacting piece of the puzzle. The requirements include both imaging and spectroscopy over a wide spectral range, from UV to IR. While temporal simultaneity of operation in various modes is a key feature, these observations are also conducted over extended periods of time. The moon is a prime site offering long unbroken observation times and high positional stability, observations at small angular separation from the sun, comparative studies of planet Earth, and valuable technical advantages. A lunar observatory should become a central piece of any coherent set of planetary missions, supplying in-situ explorations with the synoptic and comparative data necessary for proper advance planning, correlative observations during the active exploratory phase, and follow-up studies of the target body or of related objects.

  8. Inner shelf circulation patterns driven by synoptic weather systems on the South Carolina Coast

    NASA Astrophysics Data System (ADS)

    Wu, X.; Kumar, N.; Voulgaris, G.

    2015-12-01

    The meteorological forcing on the inner shelf of Long Bay, South Carolina (USA) has been analyzed using wind records extending over a period of 10 years. This analysis identified three synoptic systems classified as cold fronts, warm fronts and tropical storms. The typical temporal evolution of each system has been fully characterized statistically; the associated temporal evolution of the offshore, directional, spectral wave conditions have also been identified for the duration of each event. These typical wind and wave conditions are used to numerically investigate the response of the inner shelf. In addition, the influence of the curved coastline is examined. The numerical experiments were carried out using the ROMS and SWAN models of the Coupled Ocean-Atmosphere-Wave-Sediment-Transport (COAWST) modeling system and the results are presented. The results to-date suggest that, within the inner shelf a variability in the alongshore pressure gradient that is related to the alongshore variability of the relative angle between the wind forcing and the coastline. This coastline variability seems to affect the relative importance of the cross-shore / alongshore forcings creating different vertical structures of current at locations with different relative angle between wind forcing and coastline. Finally, the inclusion of the waves enhances the spatial differences observed for each case. These differences are explained in terms of momentum balance analysis.

  9. Spatial and temporal wind variability over Spain and its relationship with synoptic weather types

    NASA Astrophysics Data System (ADS)

    Lorente-Plazas, R.; Montavez, J. P.; García-Valero, J. A.; Gómez-Navarro, J. J.; Jerez, S.; Baró, R.; Jiménez, P. A.; Jiménez-Guerrero, P.

    2012-04-01

    The knowledge of the spatial and temporal variability of the wind over a given area is crucial for multiple purposes, like wind power generation, pollutant dispersion, risk evaluation, hydrological processes, etc. On the other hand, the assessment of the synoptic conditions related to wind behavior can be very useful for several applications. In the framework of wind power, integrating the effects of large-scale on wind behavior could improve the scheduling of the power generation, as well as to avoid damage in wind turbines due to extreme wind events. In this work, we present a methodology which contributes to the improvement in wind energy profits manly in two aspects. By one hand, performing an objective wind regionalization of an extensive area allows the identification of complementary regions. On the other hand, the association of wind field to WT can be used as a convenient tool for medium-range weather forecast, as well as to perform future wind projections under different climate change scenarios. We have analyzed the wind variability using a network of 448 wind observations evenly distributed over Spain (except Canary Islands). The first step was to obtain regions with similar temporal behavior. This was performed by using a clustering method based on the main principal modes of variability, obtained through PCA analysis. The hierarchical Ward`s method is used to provide the initial seeds to a subsequent no-hirarchical k-means method. The analysis was carried out for daily mean series of wind speed encompassing the period 2001-2007, considering each season separately. The number of regions obtained with a similar wind speed behaviour depends on the season (8 in winter, 7 in spring, 6 in summer and autumn, and 13 for the whole year). The common regions in all seasons can be roughly associated to the following areas: High Ebro Valley, Low Ebro Valley, the Mediterranean Basin, the Guadalquivir Valley, the Cantabrian Coast and the Iberian Plateaus. It is

  10. New perspectives on the synoptic and mesoscale structure of Hurricane Catarina

    NASA Astrophysics Data System (ADS)

    Pereira Filho, Augusto José; Pezza, Alexandre Bernardes; Simmonds, Ian; Lima, Raquel Silva; Vianna, Marcio

    2010-02-01

    This work explores in detail synoptic and mesoscale features of Hurricane Catarina during its life cycle from a decaying baroclinic wave to a tropical depression that underwent tropical transition (TT) and finally to a Category 2 hurricane at landfall over Santa Catarina State coast, southern Brazil. This unique system caused 11 deaths mostly off the Brazilian coast and an estimated half billion dollars in damage in a matter of a few hours on 28 March 2004. Although the closest meteorological station available was tens of kilometres away from the eye, in situ meteorological measurements provided by a work-team sent to the area where the eye made landfall unequivocally reproduces the tropical signature with category 2 strength, adding to previous analysis where this data was not available. Further analyses are based mostly on remote sensing data available at the time of the event. A classic dipole blocking set synoptic conditions for Hurricane Catarina to develop, dynamically contributing to the low wind shear observed. On the other hand, on its westward transit, large scale subsidence limited its strength and vertical development. Catarina had relatively cool SST conditions, but this was mitigated by favourable air-sea fluxes leading to latent heat release-driven processes during the mature phase. The ocean's dynamic topography also suggested the presence of nearby warm core rings which may have facilitated the transition and post-transition intensification. Since there were no records of such a system at least in the past 30 years and given that SSTs were generally below 26 °C and vertical shear was usually strong, despite all satellite data available, the system was initially classified as an extratropical cyclone. Here we hypothesise that this categorization was based on inadequate regional scale model outputs which did not account for the importance of the latent heat fluxes over the ocean. Hurricane Catarina represents a dramatic event on weather systems in

  11. Numerical modeling of an intense precipitation event and its associated lightning activity over northern Greece

    NASA Astrophysics Data System (ADS)

    Pytharoulis, I.; Kotsopoulos, S.; Tegoulias, I.; Kartsios, S.; Bampzelis, D.; Karacostas, T.

    2016-03-01

    This study investigates an intense precipitation event and its lightning activity that affected northern Greece and primarily Thessaloniki on 15 July 2014. The precipitation measurement of 98.5 mm in 15 h at the Aristotle University of Thessaloniki set a new absolute record maximum. The thermodynamic analysis indicated that the event took place in an environment that could support deep thunderstorm activity. The development of this intense event was associated with significant low-level convergence and upper-level divergence even before its triggering and a positive vertical gradient of relative vorticity advection. The high resolution (1.667 km × 1.667 km) non-hydrostatic WRF-ARW numerical weather prediction model was used to simulate this intense precipitation event, while the Lightning Potential Index was utilized to calculate the potential for lightning activity. Sensitivity experiments suggested that although the strong synoptic forcing assumed primary role in the occurrence of intense precipitation and lightning activity, their spatiotemporal variability was affected by topography. The application of the very fine resolution topography of NASA Shuttle Radar Topographic Mission improved the simulated precipitation and the calculated lightning potential.

  12. Educational Reform in Greece: Central Concepts and a Critique

    ERIC Educational Resources Information Center

    Gounari, Panayota; Grollios, George

    2012-01-01

    The case of Greece as the most recent neoliberal experiment can provide valuable insights not only about a generalized attack on the welfare state and the public good, but also about the radical changes in public education that are altering its public mission, vision, and goals. In this paper first we trace the educational landscape in Greece as…

  13. 64 FR 23675 - Electrolytic Manganese Dioxide From Greece and Japan

    Federal Register 2010, 2011, 2012, 2013, 2014

    1999-05-03

    ... orders on imports of electrolytic manganese dioxide from Greece and Japan (54 FR 15243). The Commission..., including the text of subpart F of part 207, are published at 63 FR 30599, June 5, 1998, and may be... COMMISSION Electrolytic Manganese Dioxide From Greece and Japan AGENCY: United States International...

  14. Conducting Qualitative Research on Desertification in Western Lesvos, Greece

    ERIC Educational Resources Information Center

    Iosifides, Theodoros; Politidis, Theodoros

    2005-01-01

    The main aim of this article is to present some critical methodological strategies employed in a qualitative research study on local socioeconomic development and desertification in western Lesvos, Greece. Through in-depth qualitative interviews with local producers in western Lesvos, Greece, an effort was made to identify and analyze the links…

  15. Extended Edited Synoptic Cloud Reports from Ships and Land Stations Over the Globe, 1952-1996

    SciTech Connect

    Hahn, C.J.; Warren, S.G.

    1999-08-01

    Surface synoptic weather reports for the entire globe, gathered from various available data sets, were processed, edited, and rewritten to provide a single data set of individual observations of clouds, spanning the 44 years 1952-1995 for ship data and the 26 years 1971-1996 for land station data. In addition to the cloud portion of the synoptic report, each edited report also includes the associated pressure, present weather, wind, air temperature, and dew point (and sea surface temperature over oceans).

  16. Linking storm surge activity and circulation variability along the Spanish coast through a synoptic pattern classification

    NASA Astrophysics Data System (ADS)

    Rasilla Álvarez, Domingo; Garcia Codrón, Juan Carlos

    2010-05-01

    ://www.cdc.noaa.gov/map/clim/st_data.html). The second task was to evaluate the performance of each circulation type on the spatial patterns of a daily fire danger risk index (Canadian Fire Weather Index, FWI). Finally, anomaly maps of several surface and low level climate variables, corresponding to the dates of ignition of the very large forest fires within each synoptic pattern, were calculated to provide insight of the specific conditions associated to those extreme events. A principal component analysis upon 6 hourly residuals highlighted the homogeneous behaviour of the tide gauges and provided a regional quantitative index to identify the largest storm surges. The leading PCA displayed a homogeneous spatial pattern, describing the low frequency variability along the entire coast, in spite of different orientations of the coast, accounting for more than 80% of the total variability. The second PCA displayed opposite phases between the Atlantic and the Mediterranean. Furthermore, the results suggest that surges are a regional rather than local phenomenon, probably related to the same single physical forcing. The comparison between extreme surge events and circulation patterns highlighted that single physical mechanism is represented by extratropical cyclonic disturbances located at the north-western corner of the Iberian Peninsula, responsible for an environment characterized by low pressure readings and westerly-southwesterly winds. That wind pattern acquires an onshore component in the Atlantic coast, but becomes offshore in the Mediterranean. So, the main mechanism responsible for those storm surges is the inverse barometer effect, being the wind dragging secondary. The main physical forcing of the storm surges, the extratropical cyclones, have experience a reduction of this frequency and a marked reduction in their strength since 1950, replaced by stable circulations. Both conditions suggest a long term reduction of the frequency and the magnitude of storm surges.

  17. Analysis of synoptic scale controlling factors in the distribution of gravity wave potential energy

    NASA Astrophysics Data System (ADS)

    Yang, Shih-Sian; Pan, C. J.; Das, Uma; Lai, H. C.

    2015-12-01

    In the past years, global morphology and climatology of gravity waves have been widely studied and the effects of topography and convection systems have been evaluated, but the complete gravity wave distribution could not be explained by these effects. To find the missing controlling factors, a series of synoptic scale analyses is performed in the present study to investigate relationships between synoptic scale factors and potential energy (Ep) associated with gravity waves. Global distribution of Ep during a 12-year period from 2002 to 2013 is derived using temperature profiles retrieved from observations of Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) instrument onboard the Thermosphere Ionosphere Mesosphere Energetics and Dynamics (TIMED) satellite. Synoptic scale factors obtained from ECMWF Interim reanalysis data are employed to investigate the correlation between synoptic systems and Ep. It is found that Ep values are high around extratropical cyclones over mid-latitudes (30-60°) and around the Intertropical Convergence Zone (ITCZ) over low-latitudes (10-30°). Ep values are low around subtropical highs over both mid- and low-latitudes. This is the first time that a synoptic scale analysis of Ep distribution is performed, and the influence of synoptic scale factors on Ep confirmed.

  18. A synoptic climatology of derecho producing mesoscale convective systems in the North-Central Plains

    NASA Astrophysics Data System (ADS)

    Bentley, Mace L.; Mote, Thomas L.; Byrd, Stephen F.

    2000-09-01

    Synoptic-scale environments favourable for producing derechos, or widespread convectively induced windstorms, in the North-Central Plains are examined with the goal of providing pattern-recognition/diagnosis techniques. Fifteen derechos were identified across the North-Central Plains region during 1986-1995. The synoptic environment at the initiation, mid-point and decay of each derecho was then evaluated using surface, upper-air and National Center for Atmospheric Research (NCAR)/National Center for Environmental Prediction (NCEP) reanalysis datasets.Results suggest that the synoptic environment is critical in maintaining derecho producing mesoscale convective systems (DMCSs). The synoptic environment in place downstream of the MCS initiation region determines the movement and potential strength of the system. Circulation around surface low pressure increased the instability gradient and maximized leading edge convergence in the initiation region of nearly all events regardless of DMCS location or movement. Other commonalities in the environments of these events include the presence of a weak thermal boundary, high convective instability and a layer of dry low-to-mid-tropospheric air. Of the two corridors sampled, northeastward moving derechos tend to initiate east of synoptic-scale troughs, while southeastward moving derechos form on the northeast periphery of a synoptic-scale ridge. Other differences between these two DMCS events are also discussed.

  19. Spatio-temporal activity of lightnings over Greece

    NASA Astrophysics Data System (ADS)

    Nastos, P. T.; Matsangouras, I. T.; Chronis, T. G.

    2012-04-01

    Extreme precipitation events are always associated with convective weather conditions driving to intense lightning activity: Cloud to Ground (CG), Ground to Cloud (GC) and Cloud to Cloud (CC). Thus, the study of lightnings, which typically occur during thunderstorms, gives evidence of the spatio-temporal variability of intense precipitation. Lightning is a natural phenomenon in the atmosphere, being a major cause of storm related with deaths and main trigger of forest fires during dry season. Lightning affects the many electrochemical systems of the body causing nerve damage, memory loss, personality change, and emotional problems. Besides, among the various nitrogen oxides sources, the contribution from lightning likely represents the largest uncertainty. An operational lightning detection network (LDN) has been established since 2007 by HNMS, consisting of eight time-of-arrival sensors (TOA), spatially distributed across Greek territory. In this study, the spatial and temporal variability of recorded lightnings (CG, GC and CC) are analyzed over Greece, during the period from January 14, 2008 to December 31, 2009, for the first time. The data for retrieving the location and time-of-occurrence of lightning were acquired from Hellenic National Meteorological Service (HNMS). In addition to the analysis of spatio-temporal activity over Greece, the HNMS-LDN characteristics are also presented. The results of the performed analysis reveal the specific geographical sub-regions associated with lightnings incidence. Lightning activity occurs mainly during the autumn season, followed by summer and spring. Higher frequencies of flashes appear over Ionian and Aegean Sea than over land during winter period against continental mountainous regions during summer period.

  20. Using machine learning for discovery in synoptic survey imaging data

    NASA Astrophysics Data System (ADS)

    Brink, Henrik; Richards, Joseph W.; Poznanski, Dovi; Bloom, Joshua S.; Rice, John; Negahban, Sahand; Wainwright, Martin

    2013-10-01

    Modern time-domain surveys continuously monitor large swaths of the sky to look for astronomical variability. Astrophysical discovery in such data sets is complicated by the fact that detections of real transient and variable sources are highly outnumbered by `bogus' detections caused by imperfect subtractions, atmospheric effects and detector artefacts. In this work, we present a machine-learning (ML) framework for discovery of variability in time-domain imaging surveys. Our ML methods provide probabilistic statements, in near real time, about the degree to which each newly observed source is an astrophysically relevant source of variable brightness. We provide details about each of the analysis steps involved, including compilation of the training and testing sets, construction of descriptive image-based and contextual features, and optimization of the feature subset and model tuning parameters. Using a validation set of nearly 30 000 objects from the Palomar Transient Factory, we demonstrate a missed detection rate of at most 7.7 per cent at our chosen false-positive rate of 1 per cent for an optimized ML classifier of 23 features, selected to avoid feature correlation and overfitting from an initial library of 42 attributes. Importantly, we show that our classification methodology is insensitive to mislabelled training data up to a contamination of nearly 10 per cent, making it easier to compile sufficient training sets for accurate performance in future surveys. This ML framework, if so adopted, should enable the maximization of scientific gain from future synoptic survey and enable fast follow-up decisions on the vast amounts of streaming data produced by such experiments.

  1. Synoptic-scale dust transport events in the southern Himalaya

    NASA Astrophysics Data System (ADS)

    Duchi, R.; Cristofanelli, P.; Marinoni, A.; Bourcier, L.; Laj, P.; Calzolari, F.; Adhikary, B.; Verza, G. P.; Vuillermoz, E.; Bonasoni, P.

    2014-06-01

    The variability of long-range dust transport events observed in the southern Himalaya and its relation with source areas have been studied thanks to five years’ continuous measurements which were carried out at the “Nepal Climate Observatory-Pyramid” (NCO-P, 27°57‧N, 86°48‧E), the highest Northern Hemisphere GAW-WMO global station sited at 5079 m a.s.l. in the high Khumbu valley (Nepal) on the southern Himalaya. During the period March 2006-February 2011, the analyses of the aerosol particle concentrations and LAGRANTO three-dimensional backward trajectories indicated the occurrence of 275 days affected by synoptic-scale dust transport, which account for 22.2% of the investigated period. The frequency of dust transport days (DTDs) showed a clear seasonal cycle, with the highest seasonal value observed during pre-monsoon season (33.5% of the pre-monsoon’s days are DTDs). Large enhancements in coarse aerosol number concentration N1-10 (average: +689%) and mass PM1-10 (average: +1086%) were observed during the dust transport events as compared to the days without dust (dust-free days, DFDs). In addition, the single scattering albedo (SSA) also showed higher values, ranging from 0.87 to 0.90, during DTDs with respect to DFDs (0.80-0.87). The predominant source of mineral dust reaching the measurement site was identified in the arid regions of the north-western Indian subcontinent (Thar desert), which accounted for 41.6% of the trajectories points associated with DTDs. Seasonal analysis also indicated that the winter season was significantly influenced by far western desert regions, such as North Africa and the Arabic Peninsula.

  2. Asteroid Discovery and Characterization with the Large Synoptic Survey Telescope

    NASA Astrophysics Data System (ADS)

    Jones, R. Lynne; Jurić, Mario; Ivezić, Željko

    2016-01-01

    The Large Synoptic Survey Telescope (LSST) will be a ground-based, optical, all-sky, rapid cadence survey project with tremendous potential for discovering and characterizing asteroids. With LSST's large 6.5m diameter primary mirror, a wide 9.6 square degree field of view 3.2 Gigapixel camera, and rapid observational cadence, LSST will discover more than 5 million asteroids over its ten year survey lifetime. With a single visit limiting magnitude of 24.5 in r band, LSST will be able to detect asteroids in the Main Belt down to sub-kilometer sizes. The current strawman for the LSST survey strategy is to obtain two visits (each `visit' being a pair of back-to-back 15s exposures) per field, separated by about 30 minutes, covering the entire visible sky every 3-4 days throughout the observing season, for ten years. The catalogs generated by LSST will increase the known number of small bodies in the Solar System by a factor of 10-100 times, among all populations. The median number of observations for Main Belt asteroids will be on the order of 200-300, with Near Earth Objects receiving a median of 90 observations. These observations will be spread among ugrizy bandpasses, providing photometric colors and allow sparse lightcurve inversion to determine rotation periods, spin axes, and shape information. These catalogs will be created using automated detection software, the LSST Moving Object Processing System (MOPS), that will take advantage of the carefully characterized LSST optical system, cosmetically clean camera, and recent improvements in difference imaging. Tests with the prototype MOPS software indicate that linking detections (and thus `discovery') will be possible at LSST depths with our working model for the survey strategy, but evaluation of MOPS and improvements in the survey strategy will continue. All data products and software created by LSST will be publicly available.

  3. Distributional effects of environmental policies in Greece

    NASA Astrophysics Data System (ADS)

    Lekakis, Joseph N.

    1990-07-01

    Environmental protection policies generate an equity question concerning the fair allocation of environmental benefits and costs. This paper presents evidence from Greece during the 1980s. The findings reveal that Greek environmental policies, in the form of government self-regulatory programs, are mostly regressive in nature. At the regional level these programs combine all forms of vertical equity. Since the public sector finances the majority of related expenditures out of taxes, the regressive elements of environmental policies have been reinforced by discretionary fiscal measures and tax evasion, accompanied by inflation, which have distorted the country's progressive tax system.

  4. Community noise levels in Patras, Greece

    SciTech Connect

    Stathis, T.C.

    1981-02-01

    In the city of Patras (Greece), noise measurements were made for the purposes of determining the present noise-pollution levels and the reaction of the people to them. Noise pollution is ranked second in order after air pollution, and traffic was the principal noise pollutant. The mean noise levels, in 25 monitorig stations throughout the city, were found to be high and definitely unacceptable. For three representative locations, corresponding to high, medium, and low traffic volume, various statistical noise descriptors were used, together with the other measurements, to estimate the noise environment of the entire city.

  5. Legal capacity of the elderly in Greece.

    PubMed

    Giannouli, Vaitsa; Tsolaki, Magda

    2014-01-01

    Legal capacity of the elderly people in Greece is of great legal, medical and social importance, but has received little attention till now from medical literature. This paper aims to study whether elderly people with dementia are able to participate in legal contracts like sales, purchases, loans, leases, donations and testaments. We tried to introduce a new test for the above legal-financial contracts and show some preliminary findings. The test consists of six examined relevant domains concerning basic monetary skills, cash transactions, bank statement management, financial conceptual knowledge, knowledge of potential heirs (beneficiaries) and assets/estate and finally the decision making process for different dilemmas on sales, purchases, loans, leases, donations and testaments. We studied 203 people. Eighty three people were healthy, 64 with Alzheimer's disease (AD) (10 with severe AD, 22 with moderate, and 32 with mild AD), 10 with Parkinson's disease (PD), and 46 with amnestic Mild Cognitive Impairment (aMCI). Individuals were included in the study only if they were aged 60 and over and only if they had a partner or a guardian who could give information on the individual's daily living. The exclusion criteria were predefined as follows: history of any other mental health disease and/or any other serious somatic health disease except for their official diagnosis of dementia. Results showed statistically significant differences with all three groups of patients characterized as incapable for legal-financial actions. Patients with severe AD (P<0.001), patients with moderate AD (P<0.001), patients with mild AD (P<0.001), patients with PD (P<0.001) and aMCI patients (P<0.001) differed significantly from healthy controls. Further research should include more extensive sampling of elderly patients with varying demographic characteristics in Greece, to confirm and expand our initial findings. In conclusion, our new test which is based on Marson's theoretical model

  6. The role of synoptic and intraseasonal anomalies in the life cycle of summer rainfall extremes over South America

    NASA Astrophysics Data System (ADS)

    Hirata, Fernando E.; Grimm, Alice M.

    2016-05-01

    The main goal of this study is to describe the role of synoptic and intraseasonal anomalies during the life cycle of summer rainfall extremes over South America. Eastward-propagating synoptic-scale midlatitude waves are the main drivers of extreme precipitation events south of the Amazon and their interaction with intraseasonal anomalies over South America is important for heavy rainfall over the South Atlantic convergence zone (SACZ) region and the La Plata basin. Madden-Julian Oscillation (MJO) convective activity in the western Pacific (phases 6 and 7) leads 31 out of 81 extremes over the SACZ region by nearly 10 days. The connection between the MJO and rainfall extremes in other regions is less robust. During El Niño seasons extremes are more frequent in the La Plata basin, with decreased importance of intraseasonal anomalies. Precipitation extremes over the La Plata basin tend to be less frequent and also shorter during La Niña summers and, consequently, less hazardous. In the SACZ and the southeastern Brazilian coast, heavy rainfall is also more frequent under El Niño conditions, while La Niña episodes also increase extreme events in the southeastern coast. Extremes over the southeastern coast during El Niños are favored by strong intraseasonal anomalies flanking the subtropical jet, while during La Niñas intraseasonal anomalies are not significant.

  7. The influence of Black Sea Water inflow and its synoptic time-scale variability in the North Aegean Sea hydrodynamics

    NASA Astrophysics Data System (ADS)

    Mavropoulou, Apostolia-Maria; Mantziafou, Anneta; Jarosz, Ewa; Sofianos, Sarantis

    2016-02-01

    The exchange water fluxes between the Black Sea and the North Aegean Sea through the Dardanelles Strait constitute an essential factor for the general circulation of the region. The Black Sea Water (BSW) inflow to the Aegean plays an important role in the hydrography and circulation of the basin and can affect the North Aegean deep water formation processes. Numerical experiments evaluating the influence of the time-scale variability (synoptic and seasonal) and the seasonality (period of maximum/minimum) of the Black Sea Water inflow on the dynamics of the North Aegean basin were performed. The experiments were carried out for the period from August 2008 to October 2009, using observed upper and lower-layer fluxes from the Dardanelles Strait, high-resolution atmospheric forcing, and boundary conditions derived from an operational system (ALERMO). The large-scale spatial patterns of the circulation and the seasonal variability of the North Aegean circulation show that dynamics of the basin can effectively absorb most of the Black Sea Water inflow variability. The overall cyclonic circulation of the North Aegean Sea and the predominant cyclonic and anti-cyclonic features are robust and are little affected by the different lateral fluxes. However, differences in the seasonality of the BSW inflow have an important impact in the North Aegean water column structure, while the synoptic variability observed in the Black Sea Water inflow affects the kinetic energy of the basin and the pathway of the Black Sea Water plume.

  8. A 26 year high-resolution dynamical downscaling over the Wasatch Mountains: Synoptic effects on winter precipitation performance

    NASA Astrophysics Data System (ADS)

    Scalzitti, Jason; Strong, Courtenay; Kochanski, Adam K.

    2016-04-01

    A 26 year high-resolution dynamical downscaling over the Wasatch Mountains of Utah, USA, was performed using the Weather Research and Forecasting model with initial and boundary conditions derived from Climate Forecast System Reanalysis. Precipitation validation was conducted on the inner (4 km resolution) domain with Snowpack Telemetry (SNOTEL) and Parameter-elevation Regressions on Independent Slopes Model data sets. Analysis of seasonal performance reveals the model's overall good skill at reproducing the spatial distribution of precipitation. Annual precipitation validates within ˜20% of SNOTEL. The largest monthly biases occurred in December-January (˜+30%) stemming from a small set of high-precipitation events. Composite analysis of cold season days with large positive or negative precipitation biases reveals two distinct synoptic regimes with significantly different moisture, temperature, and circulation patterns that respectively enhanced geopotential height and moisture biases consistent with the sign of their mean precipitation biases. The number of cold season days with large (>5 mm) positive precipitation bias was negatively correlated with El Niño (r = - 0.55), indicating storm track-related effects on the sign of the bias consistent with the distinct synoptic regimes revealed by the above-noted composite analyses.

  9. [Medical myths and notions in Ancient Greece].

    PubMed

    Boulogne, J

    2001-01-01

    The article deals with the views on health and disease prevalent in Ancient Greece, the cradle of modern European medicine, focusing on the ever-present myths functioning in that realm despite attempts to rationally explain medical phenomena. On the basis of the works of Hippocrates and Galen, the author has distinguished five different epistemological attitudes towards those phenomena: the holistic, macrocosmological, monistic, anti-hypothetical and eclectic. The first was based on the idea of mechanical and logical causes. In medicine it is marked by determinism connected with climatic conditions. Hippocrates believed that health depended on the weather, in particular on the effects of winds, types of water and properties of soil. Myth emerged in this conception in the way matter - earth, water, air and fire - was conceived, particular in the properties ascribed to them: cold, humidity, aridity and warmth. The author charges that this conception was permeated with ethnocentrism and cites examples invoked by Hippocrates on the basis of his observations on the Scythians. The macrocosmological attitude involves subordinating medicine to cosmology. Man's body is a microcosm. The author cites the treatise 'On Diets', in which the greatest importance both in the universe and in processes taking place in the human body as ascribed to two factors - fire and water. Their combination was said to have played a crucial role in the typology of corporal and mental constitutions. Those features, together with the seasons of the year, mode of behaviour and food, constitute the four forces guiding vital processes. The author then presents the embryogenic conception contained in the cosmological treatise. It was based on such things as numerological speculations, hence - despite its rationalistic assumptions, consigns it to the mythic. The third attitude, the monistic approach, presents a treatise ascribed to Hippocrates 'On the Sacred Disease' and dealing with epilepsy. The

  10. Synoptic climatology of winter intense precipitation events along the Mediterranean coasts

    NASA Astrophysics Data System (ADS)

    Reale, M.; Lionello, P.

    2013-07-01

    Pa highlights the important role of cyclone depth, circulation strength, surrounding synoptic condition, and of slow speed of the cyclone center for producing intense precipitation events.