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Polar anthropogenic organic micropollutants are frequently detected in freshwater and discharged on large scale into marine systems. In this work the results of 153 samples collected from the shorelines of the Baltic Sea (Germany), Northern Adriatic Sea (Italy), Aegean Sea and Dardanelles (Greece & Turkey), San Francisco Bay (USA), Pacific Ocean (USA), Mediterranean Sea (Israel), and Balearic Sea (Spain) are presented. The samples were analyzed for various classes of micropollutants such as pharmaceuticals, corrosion inhibitors, biocides, and stimulants. Caffeine, paraxanthine, theobromine, tolyltriazole, 1H-benzotriazole, and atrazine were detected in >50% of all samples. The detection frequencies of carbamazepine, iopamidol, diuron, sulfamethoxazole, paracetamol, theophylline, and atenolol were between 20% and 32%. As caffeine is linked to untreated wastewater, the widespread occurrence of raw sewage in marine environments and thus potentially elevated nutrient concentrations and risk for the presence of wastewater-related pathogens is remarkable. 相似文献
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The western sector of the Tagliamento River basin (Friuli Venezia-Giulia Region; northern Italy) is characterized by important water resources, both superficial and underground. In particular, in the Quaternary deposits of the plain, up to a depth of 500 m, six artesian aquifer systems exist. A large amount of lithological, geomorphological, and hydrogeological data is presented, allowing for definition of (a) the principal aquifer system of the area to a depth of about 500 m; (b) geometrical characteristics of the aquifers (thickness, lateral extension, etc); (c) the hydraulic parameters (hydraulic conductivity, transmissivity); (d) chemico-physical characteristics of the water; and (e) vulnerability to pollution of the aquifer systems. In a test area, where many boreholes were drilled for fresh water supply, the conceptual hydrogeological model was integrated by a detailed and repeated three-dimensional (3D) resistivity survey using combined electrical resistivity tomography (ERT) and time-domain electromagnetic (TDEM) soundings. ERT investigation was mainly used to get detailed information about geometry and porosity of the overburden and to calibrate the shallowest TDEM information. 相似文献
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Abstract Industrial land development has become a key feature of urbanization in Greater Jakarta, one of the largest metropolitan areas in Southeast Asia. Following Suharto's market-oriented policy measures in the late 1980s, private developers have dominated the land development projects in Greater Jakarta. The article investigates the extent to which these private industrial centers have effectively reduced the domination of Jakarta in shaping the entire metropolitan structure. The analysis indicates that major suburban industrial centers have captured most of the manufacturing employment that has dispersed from Jakarta. The industrial centers have now increasingly specialized and diversified. It is likely that a polycentric metropolitan structure will emerge in the future. 相似文献
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D. Founda H. D. Kambezidis M. Petrakis P. Zanis C. Zerefos 《Theoretical and Applied Climatology》2009,97(3-4):385-389
Two discontinuities were detected in the air-temperature time series at the meteorological station of the National Observatory of Athens. The first discontinuity reflects the instrumental change, which took place in June 1995 and the second discontinuity (and most pronounced) the application of a correction factor to the temperature values (in January 1997), after a calibration of the new thermometers. As a result, a cooling bias was observed after June 1995 and a warming bias after January 1997. The magnitude of bias exhibited a seasonal variability being more pronounced and reaching up to 0.67°C during the warm period of the year. The common period of operation of the ‘old’ and ‘new’ instrumentation was used for the estimation of monthly correction factors and the removal of the bias. The application of the new correction factors, restore the continuity in the air temperature record after June 1995. 相似文献
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Simulating maximum and minimum temperature over Greece: a comparison of three downscaling techniques 总被引：1，自引：0，他引：1
E. Kostopoulou C. Giannakopoulos C. Anagnostopoulou K. Tolika P. Maheras M. Vafiadis D. Founda 《Theoretical and Applied Climatology》2007,90(1-2):65-82
Summary Statistical downscaling techniques have been developed for the generation of maximum and minimum temperatures in Greece. This
research focuses on the four conventional seasons, and three downscaling approaches, Multiple Linear Regression using a circulation
type approach (MLRct), Canonical Correlation Analysis (CCA) and Artificial Neural Networks (ANNs), are employed and compared
to assess their performance skills. Models were developed individually for each variable (Tmax, Tmin), station and season. The accuracy of downscaled values has been quantified in terms of a number of performance criteria,
such as differences of the mean and standard deviation ratios between observed and modelled data, the correlation coefficients
of the two sets, and also the RMSEs of the downscaled values relative to the observed. All methods revealed that during the
cool season Tmax tends to be better reproduced, whereas Tmin is overestimated, particularly over western Greece, which is characterised by higher orography. With respect to the warm
season, the simulation of Tmax reveals greater divergence, whereas Tmin is better generated. The distinction between the three techniques is somewhat blurred. None of the methods were found to
be superior to the others and each has been shown to be a good estimator in some cases. This study concludes that all proposed
methods comprise useful tools for simulating daily temperatures, as the high correlation coefficients, between observed and
downscaled values, have demonstrated. However, the importance of local factors, which affect the natural variability of temperature,
has been emphasised indicating that the geography of a region constitutes an important and rather complex factor, which should
be included in models to improve their performance. 相似文献
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Robert G. Mann Seb Oliver Ruth Carballo Alberto Franceschini Michael Rowan-Robinson Alan F. Heavens Maria Kontizas David Elbaz Anastasios Dapergolas Evanghelos Kontizas Gian Luigi Granato Laura Silva Dimitra Rigopoulou J. Ignacio Gonzalez-Serrano Aprajita Verma Steve Serjeant reas Efstathiou Paul P. van der Werf 《Monthly notices of the Royal Astronomical Society》2002,332(3):549-574
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A. Kalimeris D. Founda C. Giannakopoulos F. Pierros 《Theoretical and Applied Climatology》2012,109(1-2):51-72
The present study examines the variability of the precipitation regime across the Ionian Islands complex, Greece (Central Mediterranean), for a period spanning more than one century. Significant negative long-term linear trends in the annual precipitation totals are observed, more pronounced in the southern parts of the studied area, while a climatic discontinuity possibly occurred during the 1970s, manifested first in the southern Ionian. Statistically significant nonlinear trends and subdecadal intermittent oscillations were detected using Monte Carlo singular spectral analysis. The correlation of the winter precipitation variability at Ionian complex with the North Atlantic Oscillation anomalies was also investigated and extended in the frequency domain. Finally, future projections were performed using an ensemble of Regional Climatic Models. Model simulations suggested a decrease of the order of ～20% or more in the mean annual precipitation of the area by the end of the century. 相似文献
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This paper examines the eigenvalues of multi‐span seismically isolated bridges in which the transverse displacement of the deck at the end abutments is restricted. With this constraint the deck is fully isolated along the longitudinal direction, whereas along the transverse direction the deck is a simple‐supported beam at the end abutments which enjoys concentrated restoring forces from the isolation bearings at the center piers. For moderate long bridges, the first natural period of the bridge is the first longitudinal period, while the first transverse period is the second period, given that the flexural rigidity of the deck along the transverse direction shortens the isolation period offered by the bearings in that direction. This paper shows that for isolated bridges longer than a certain critical length, the first transverse period becomes longer than the first longitudinal period despite the presence of the flexural rigidity of the deck. This critical length depends on whether the bridge is isolated on elastomeric bearings or on spherical sliding bearings. This result is also predicted with established commercially available numerical codes only when several additional nodes are added along the beam elements which are modeling the deck in‐between the bridge piers. On the other hand, this result cannot be captured with the limiting idealization of a beam on continuous distributed springs (beam on Wrinkler foundation)—a finding that has practical significance in design and system identification studies. Finally, the paper shows that the normalized transverse eigenperiods of any finite‐span deck are self‐similar solutions that can be represented by a single master curve and are independent of the longitudinal isolation period or on whether the deck is supported on elastomeric or spherical sliding bearings. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献