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Mihai Dima - One of the best experts on this subject based on the ideXlab platform.
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Impacts of the North Atlantic Oscillation and the El Niño–Southern Oscillation on Danube River flow variability
Geophysical Research Letters, 2004Co-Authors: Norel Rimbu, Mihai Dima, Gerrit Lohmann, Sabina StefanAbstract:[1] Based on analysis of observational data we show that the impact of the North Atlantic Oscillation (NAO) and El Nino–Southern Oscillation (ENSO) on the Danube River flow variability shows important decadal variations. A lag-correlation analysis reveals that winter SST from tropical Pacific and some regions from the North Atlantic are significantly correlated with the streamflow variations from spring and summer suggesting a possible predictive skill of the Danube River flow anomalies in these seasons using winter SST as a predictor.
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decadal variability of the Danube River flow in the lower basin and its relation with the north atlantic oscillation
International Journal of Climatology, 2002Co-Authors: Norel Rimbu, Constanţa Boroneanţ, Carmen Buţă, Mihai DimaAbstract:The decadal variability (>5 years) of the Danube River flow in the lower basin and its connection with the North Atlantic Oscillation (NAO) is analysed for the period 1931–95. Associated linkages with precipitation (PP) in the European sector, global sea surface temperature (SST) and atmospheric circulation for the period 1931–81, and the 500 hPa geopotential heights (G500) over the Northern Hemisphere for the period 1948–95 are also investigated. The results show that there is an out-of-phase relationship between the time series of the Danube River flow anomalies and the NAO index. The time series of a PP index, defined as the average of normalized precipitation anomalies over a large area including the Danube basin, presents a time evolution similar to that of the River flow anomalies. The correlation maps between the River flow anomalies and global SST show coherent large-scale patterns. High values of the Danube River flow are associated with a tripole-like SST structure in the North Atlantic similar to that appearing during the negative phase of the NAO, and with negative SST anomalies in the central North Pacific and positive SST anomalies in the eastern and central tropical Pacific. Physically consistent sea level pressure and 500 hPa geopotential height are obtained. Copyright © 2002 Royal Meteorological Society.
Norel Rimbu - One of the best experts on this subject based on the ideXlab platform.
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Impacts of the North Atlantic Oscillation and the El Niño–Southern Oscillation on Danube River flow variability
Geophysical Research Letters, 2004Co-Authors: Norel Rimbu, Mihai Dima, Gerrit Lohmann, Sabina StefanAbstract:[1] Based on analysis of observational data we show that the impact of the North Atlantic Oscillation (NAO) and El Nino–Southern Oscillation (ENSO) on the Danube River flow variability shows important decadal variations. A lag-correlation analysis reveals that winter SST from tropical Pacific and some regions from the North Atlantic are significantly correlated with the streamflow variations from spring and summer suggesting a possible predictive skill of the Danube River flow anomalies in these seasons using winter SST as a predictor.
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decadal variability of the Danube River flow in the lower basin and its relation with the north atlantic oscillation
International Journal of Climatology, 2002Co-Authors: Norel Rimbu, Constanţa Boroneanţ, Carmen Buţă, Mihai DimaAbstract:The decadal variability (>5 years) of the Danube River flow in the lower basin and its connection with the North Atlantic Oscillation (NAO) is analysed for the period 1931–95. Associated linkages with precipitation (PP) in the European sector, global sea surface temperature (SST) and atmospheric circulation for the period 1931–81, and the 500 hPa geopotential heights (G500) over the Northern Hemisphere for the period 1948–95 are also investigated. The results show that there is an out-of-phase relationship between the time series of the Danube River flow anomalies and the NAO index. The time series of a PP index, defined as the average of normalized precipitation anomalies over a large area including the Danube basin, presents a time evolution similar to that of the River flow anomalies. The correlation maps between the River flow anomalies and global SST show coherent large-scale patterns. High values of the Danube River flow are associated with a tripole-like SST structure in the North Atlantic similar to that appearing during the negative phase of the NAO, and with negative SST anomalies in the central North Pacific and positive SST anomalies in the eastern and central tropical Pacific. Physically consistent sea level pressure and 500 hPa geopotential height are obtained. Copyright © 2002 Royal Meteorological Society.
James W Murray - One of the best experts on this subject based on the ideXlab platform.
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trace metal composition of particulate matter of the Danube River and turkish Rivers draining into the black sea
Marine Chemistry, 2008Co-Authors: Oguz Yigiterhan, James W MurrayAbstract:Abstract We determined the composition of particles from several Rivers entering the Black Sea as part of a broader study of the composition of suspended matter and sediments in the Black Sea. Suspended matter and surface sediment samples were collected from the Danube River draining from Europe and from four Turkish Rivers (Sakarya, Yenice (Filyos), Kizilirmak and Yesilirmak Rivers) in Anatolia. All samples were digested and analyzed by inductively coupled plasma-mass spectrometry and atomic absorption spectrometry (flame and graphite furnace) instruments. The elements analyzed included Al, Ti, V, Cr, Mn, Fe, Co, Cu, Zn, Mo, Ag, Cd, Ba, Pb and U. The concentrations were compared as solid phase concentrations (ppm) and as Metal to Al (Me/Al) ratios. The compositions of the particulate matter data from Turkish Rivers and surface sediment from the Danube River were very similar to each other and the average for the world's Rivers. Both had slightly higher concentrations than global average crust. A suspended matter sample from the Danube River had elevated concentrations for some elements (Ag, Pb, Zn, Cd, Cu and Mn) that were probably due to anthropogenic contamination suggesting that some hot spots may exist in the Danube that need to be studied more thoroughly. We recommend that the best choice for subtracting the terrigenous component from Black Sea particulate and sediment samples is the average of the Turkish Rivers suspended matter and Danube River sediment samples.
Pavla Pekárová - One of the best experts on this subject based on the ideXlab platform.
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Analyzing temporal changes in maximum runoff volume series of the Danube River
IOP Conference Series: Earth and Environmental Science, 2008Co-Authors: Dana Halmová, Pavla Pekárová, Jan Pekar, Milan OnderkaAbstract:Several hypotheses claim that more extremes in climatic and hydrologic phenomena are anticipated. In order to verify such hypotheses it is inevitable to examine the past periods by thoroughly analyzing historical data. In the present study, the annual maximum runoff volumes with t-day durations were calculated for a 130-year series of mean daily discharge of Danube River at Bratislava gauge (Slovakia). Statistical methods were used to clarify how the maximum runoff volumes of the Danube River changed over two historical periods (1876-1940 and 1941-2005). The conclusion is that the runoff volume regime during floods has not changed significantly during the last 130 years.
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retrieval of suspended particulate matter concentrations in the Danube River from landsat etm data
Science of The Total Environment, 2008Co-Authors: Milan Onderka, Pavla PekárováAbstract:Alternations in River channel morphology result in a disturbed natural transport of suspended particulate matter (SPM). Suspended particulate matter serves as a transport medium for various pollutants, e.g. heavy metals. It is therefore important to understand how artificial obstructions alter the natural transport of suspended matter. Measurements of SPM in Rivers are traditionally carried out during in situ sampling campaigns, which can provide only a limited view of the actual spatial distribution of suspended matter over large distances. Several authors have studied how space-borne remote sensing could be used for mapping of water quality in standing waters, but with only little attention paid to Rivers. This paper describes the methodology how a Landsat ETM image was used to map the spatial patterns of SPM in the Slovak portion of the Danube River. Results of our investigation reveal that the Danube River in Slovakia exhibits gradual longitudinal decrease in concentrations of SPM. Based on a strong relationship between the Landsat near-infrared band (TM4) and field measurements, we developed a map of suspended particulate matter in the Danube River with a standard error (SE) of 2.92 mg/L. This study aims to show how archived satellite data and historical water quality data can be used for monitoring of SPM in large Rivers. A methodology describing the minimum samples required for sufficiently accurate results is discussed in this paper also.
Oguz Yigiterhan - One of the best experts on this subject based on the ideXlab platform.
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trace metal composition of particulate matter of the Danube River and turkish Rivers draining into the black sea
Marine Chemistry, 2008Co-Authors: Oguz Yigiterhan, James W MurrayAbstract:Abstract We determined the composition of particles from several Rivers entering the Black Sea as part of a broader study of the composition of suspended matter and sediments in the Black Sea. Suspended matter and surface sediment samples were collected from the Danube River draining from Europe and from four Turkish Rivers (Sakarya, Yenice (Filyos), Kizilirmak and Yesilirmak Rivers) in Anatolia. All samples were digested and analyzed by inductively coupled plasma-mass spectrometry and atomic absorption spectrometry (flame and graphite furnace) instruments. The elements analyzed included Al, Ti, V, Cr, Mn, Fe, Co, Cu, Zn, Mo, Ag, Cd, Ba, Pb and U. The concentrations were compared as solid phase concentrations (ppm) and as Metal to Al (Me/Al) ratios. The compositions of the particulate matter data from Turkish Rivers and surface sediment from the Danube River were very similar to each other and the average for the world's Rivers. Both had slightly higher concentrations than global average crust. A suspended matter sample from the Danube River had elevated concentrations for some elements (Ag, Pb, Zn, Cd, Cu and Mn) that were probably due to anthropogenic contamination suggesting that some hot spots may exist in the Danube that need to be studied more thoroughly. We recommend that the best choice for subtracting the terrigenous component from Black Sea particulate and sediment samples is the average of the Turkish Rivers suspended matter and Danube River sediment samples.
