Changes in ozone trends over the northern hemisphere middle latitudes during the period 1970–1990     

J. W. Krzyścin 《Theoretical and Applied Climatology》1994,49(1):1-7

Summary Composite time series combining the results of total ozone measurements taken at Dobson stations located within the latitude band 30°N–60°N, in Europe, and North America, have been examined in order to detect any trends. Various regression trend models were used to identify any trend variations over the regions during the period 1970–1990. The results of fitting the models to the data imply that the model which assumes a linear trend provides precise information about the long-term ozone trends (trends during the period 1970–1990). The study identifies short-term summer trends in the 1980s that are evidently more strongly negative than trends that occur in the 1970s (the differences are statistically significant at the 2 level). The year-round loss (in all analyzed regions) and the winter loss in total ozone (the belt 30°N–60°N) N. America, during the 1980s are about 2–3 times higher than the losses during the 1970s (the differences are statistically significant at the 1 level).With 1 Figure  相似文献   

Dependency of geodynamic parameters on the GNSS constellation     

Stefano Scaramuzza  Rolf Dach  Gerhard Beutler  Daniel Arnold  Andreja Sušnik  Adrian Jäggi 《Journal of Geodesy》2018,92(1):93-104

Significant differences in time series of geodynamic parameters determined with different Global Navigation Satellite Systems (GNSS) exist and are only partially explained. We study whether the different number of orbital planes within a particular GNSS contributes to the observed differences by analyzing time series of geocenter coordinates (GCCs) and pole coordinates estimated from several real and virtual GNSS constellations: GPS, GLONASS, a combined GPS/GLONASS constellation, and two virtual GPS sub-systems, which are obtained by splitting up the original GPS constellation into two groups of three orbital planes each. The computed constellation-specific GCCs and pole coordinates are analyzed for systematic differences, and their spectral behavior and formal errors are inspected. We show that the number of orbital planes barely influences the geocenter estimates. GLONASS’ larger inclination and formal errors of the orbits seem to be the main reason for the initially observed differences. A smaller number of orbital planes may lead, however, to degradations in the estimates of the pole coordinates. A clear signal at three cycles per year is visible in the spectra of the differences between our estimates of the pole coordinates and the corresponding IERS 08 C04 values. Combinations of two 3-plane systems, even with similar ascending nodes, reduce this signal. The understanding of the relation between the satellite constellations and the resulting geodynamic parameters is important, because the GNSS currently under development, such as the European Galileo and the medium Earth orbit constellation of the Chinese BeiDou system, also consist of only three orbital planes.  相似文献   

Validation of Galileo orbits using SLR with a focus on satellites launched into incorrect orbital planes     

Krzysztof Sośnica  Lars Prange  Kamil Kaźmierski  Grzegorz Bury  Mateusz Drożdżewski  Radosław Zajdel  Tomasz Hadas 《Journal of Geodesy》2018,92(2):131-148

The space segment of the European Global Navigation Satellite System (GNSS) Galileo consists of In-Orbit Validation (IOV) and Full Operational Capability (FOC) spacecraft. The first pair of FOC satellites was launched into an incorrect, highly eccentric orbital plane with a lower than nominal inclination angle. All Galileo satellites are equipped with satellite laser ranging (SLR) retroreflectors which allow, for example, for the assessment of the orbit quality or for the SLR–GNSS co-location in space. The number of SLR observations to Galileo satellites has been continuously increasing thanks to a series of intensive campaigns devoted to SLR tracking of GNSS satellites initiated by the International Laser Ranging Service. This paper assesses systematic effects and quality of Galileo orbits using SLR data with a main focus on Galileo satellites launched into incorrect orbits. We compare the SLR observations with respect to microwave-based Galileo orbits generated by the Center for Orbit Determination in Europe (CODE) in the framework of the International GNSS Service Multi-GNSS Experiment for the period 2014.0–2016.5. We analyze the SLR signature effect, which is characterized by the dependency of SLR residuals with respect to various incidence angles of laser beams for stations equipped with single-photon and multi-photon detectors. Surprisingly, the CODE orbit quality of satellites in the incorrect orbital planes is not worse than that of nominal FOC and IOV orbits. The RMS of SLR residuals is even lower by 5.0 and 1.5 mm for satellites in the incorrect orbital planes than for FOC and IOV satellites, respectively. The mean SLR offsets equal \(-44.9, -35.0\), and \(-22.4\) mm for IOV, FOC, and satellites in the incorrect orbital plane. Finally, we found that the empirical orbit models, which were originally designed for precise orbit determination of GNSS satellites in circular orbits, provide fully appropriate results also for highly eccentric orbits with variable linear and angular velocities.  相似文献   

On the Asymmetric Longitudinal Oscillations of a Pikelner’s Model Prominence     

J. Kraśkiewicz  K. Murawski  A. Solov’ev  A. K. Srivastava 《Solar physics》2016,291(2):429-444

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Erratum to: A consistent combination of GNSS and SLR with minimum constraints     

Susanne Glaser  Mathias Fritsche  Krzysztof Sośnica  Carlos Javier Rodríguez-Solano  Kan Wang  Rolf Dach  Urs Hugentobler  Markus Rothacher  Reinhard Dietrich 《Journal of Geodesy》2015,89(12):1181-1182

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From mantle roots to surface eruptions: Cenozoic and Mesozoic continental basaltic magmatism     

Horst Kämpf  Karoly Németh Dr.  Jacek Puziewicz  Jan Mrlina  Wolfram H. Geissler 《International Journal of Earth Sciences》2015,104(8):1909-1912

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Differential biomagnification of PCB, PBDE, Hg and Radiocesium in the food web of the European hake from the NW Mediterranean     

Harmelin-Vivien M  Bodiguel X  Charmasson S  Loizeau V  Mellon-Duval C  Tronczyński J  Cossa D 《Marine pollution bulletin》2012,64(5):974-983

Consumption of marine organisms represents one of the main exposure sources of contaminants for human populations. To obtain a global view of the contamination in commercial fish in the NW Mediterranean Sea, we analysed four types of priority contaminants (PCBs, PBDEs, Hg and (137)Cs) in the European hake, Merluccius merluccius, from the Gulf of Lions in relation with organism's trophic level (δ(15)N). All contaminants presented a significant increase in concentration in hake muscle with trophic level. However, obvious differences between contaminants were evidenced. Biomagnification factors (BMF and FWMF) along the hake food web were higher for Hg and CB-153 than for BDE-47 and (137)Cs, and increase in contaminant concentration with trophic level occurred at different rates depending on contaminants. Such differences of biomagnification patterns can be related to physico-chemical properties of the different contaminants.  相似文献   

Interannual variability of tropospheric NO2 column over central Europe — observations from SCIAMACHY and GEM-AQ model simulations     

Karol Szymankiewicz  Jacek W. Kaminski  Joanna Struzewska 《Acta Geophysica》2014,62(4):915-929

Spatial and temporal variability of NO₂ tropospheric column over Europe was analyzed for a 3 year period (2008–2010) based on monthly average observations from SCIAMACHY and the GEM-AQ model results. The GEM-AQ model was run in a global variable configuration with a resolution of ～15 km over Central Europe. Spatial averaged time series were calculated for two selected regions in Western and Central Europe in order to assess the seasonal and interannual variability of the tropospheric NO₂. The spatial pattern is similar near large emission sources for consecutive years. However, in remote regions there are differences due to interannual variability of meteorological conditions. Highest tropospheric NO₂ column values (over 150 × 10¹⁵ molecules/cm²) were persistent over the Benelux and over most of the European agglomerations. The general agreement between modelled and observed NO₂ column is good. In the remote areas, the modelled NO₂ column shows weaker gradients than the observed field.  相似文献   

Groundwater flow rate and contaminant migration in fissure-karstic aquifer of Opole Triassic system southwest Poland   总被引：1，自引：0，他引：1  

J. Kryza  S. Staśko 《Environmental Geology》2000,39(3-4):384-389

 This paper presents hydrogeological problems occurring during municipal water exploitation and mine dewatering. These activities result in groundwater quantity and quality changes in the fissure-karstic aquifer. Increase of nitrate concentration up to 12 mg NNO₃/l due to intensive fertilizer use, and high tritium concentration, show water system impact up to 100 m depth. Intensive water exploitation produces large cones of depression with over 40-m water-level depletion in the Opole region. Flow rates of major components and isotopes have been verified by chemical migration history. Some aspects of the protection policy of this type of aquifer are also discussed. Received: 7 March 1997 · Accepted: 17 November 1998  相似文献   

Drought and its effects on spring discharge regimes in Poland and Germany during the 2015 drought     

Stanisław Staśko  Sebastian Buczyński 《水文科学杂志》2018,63(5):741-751

Areas of Western and Central Europe were severely affected by devastating droughts in 2003 and 2015. A sharp decrease in annual atmospheric precipitation led to diminished spring discharges. Analysis of the fluctuations in discharge from three groups of springs in the south of Poland, namely in the Sudetes and Carpathian mountains, and in the German province of Bavaria revealed an average discharge reduction ranging from 52 to 4%. The study proved the existence of a relationship between diminished groundwater recharge from precipitation and the type of rock forming the reservoir as well as the parameters of the rock in the drained catchment. Spring discharge regime was compared for various periods to show that a decline in the regime correlates with a decline in river flow rate; considering the continually changing weather patterns, this correlation is arguably a key factor in sustainable water management.  相似文献