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31.
Collecting marine data during hydroacoustic research surveys is a complex task, which not only consists of measurements but also analysis, validation, and interpretation of information acquired by various sensors. Automatic integration, visualization, and processing of collected data allow for a more precise investigation of the researched phenomena. The paper presents a dedicated Web-based system for fusion and dissemination of data from satellite imagery, hydrological measurements using CTD probes, acoustic surveys by multibeam systems, side-scan sonars and singlebeam echosounders, as well as live radar feed and oil spill spread models. The system has been designed as a tool for supporting research using the aforementioned techniques. 相似文献
32.
Recent summer precipitation trends in the Greater Horn of Africa and the emerging role of Indian Ocean sea surface temperature 总被引：1，自引：0，他引：1
A. Park Williams Chris Funk Joel Michaelsen Sara A. Rauscher Iain Robertson Tommy H. G. Wils Marcin Koprowski Zewdu Eshetu Neil J. Loader 《Climate Dynamics》2012,39(9-10):2307-2328
We utilize a variety of climate datasets to examine impacts of two mechanisms on precipitation in the Greater Horn of Africa (GHA) during northern-hemisphere summer. First, surface-pressure gradients draw moist air toward the GHA from the tropical Atlantic Ocean and Congo Basin. Variability of the strength of these gradients strongly influences GHA precipitation totals and accounts for important phenomena such as the 1960s–1980s rainfall decline and devastating 1984 drought. Following the 1980s, precipitation variability became increasingly influenced by the southern tropical Indian Ocean (STIO) region. Within this region, increases in sea-surface temperature, evaporation, and precipitation are linked with increased exports of dry mid-tropospheric air from the STIO region toward the GHA. Convergence of dry air above the GHA reduces local convection and precipitation. It also produces a clockwise circulation response near the ground that reduces moisture transports from the Congo Basin. Because precipitation originating in the Congo Basin has a unique isotopic signature, records of moisture transports from the Congo Basin may be preserved in the isotopic composition of annual tree rings in the Ethiopian Highlands. A negative trend in tree-ring oxygen-18 during the past half century suggests a decline in the proportion of precipitation originating from the Congo Basin. This trend may not be part of a natural cycle that will soon rebound because climate models characterize Indian Ocean warming as a principal signature of greenhouse-gas induced climate change. We therefore expect surface warming in the STIO region to continue to negatively impact GHA precipitation during northern-hemisphere summer. 相似文献
33.
Bogdan Saletnik Grzegorz Zaguła Dorota Grabek-Lejko Idalia Kasprzyk Marcin Bajcar Maria Czernicka Czesław Puchalski 《Environmental Earth Sciences》2017,76(16):574
Because of their physicochemical properties, biochars can be used as sorption materials for removal of toxic substances. The purpose of the present study was to determine whether biochar obtained from cones of larch (Larix decidua Mill. subsp. decidua) and spruce (Picea abies L. H. Karst) could be used as a sorbent for Cd2+, Pb2+ and Co2+ in aqueous solutions. So far, this feedstock had not been tested in this respect. The material was subjected to pyrolysis at 500 and 600 °C for the duration of 5, 10 and 15 min. The obtained pyrolysates were found to differ in terms of pH and the contents of the essential macroelements. The different values of these parameters were determined for varying temperature, duration of the pyrolysis process and type of feedstock. Sorption capacities of the biochars for removal of Cd2+, Pb2+ and Co2+ were examined using simulated contamination of aqueous solutions with salts of these metals. The findings showed the highest, nearly complete, removal for Pb2+ were maximum 99.7%, and almost three times lower value for Cd2+ and Co2+ (respectively, 35.7 and 24.8%). It was demonstrated that pyrolysis of conifer cones produced optimum sorption capacities when the process was conducted at a temperature of 500 °C for the duration of 5 min. It was shown that products of spruce cone pyrolysis were characterized by better sorption capacity in comparison with products of larch cone pyrolysis. The properties of conifer cone biochar create the possibility of using it as an adsorbent in water and wastewater treatment as well as in production of filters and activated carbon. 相似文献
34.
Paulina Rusanowska Monika Harnisz Marcin Zieli&#x;ski Marcin D&#x;bowski Ewa Korzeniewska Marta Kisielewska Ewa Amenda 《洁净——土壤、空气、水》2020,48(2)
Methane fermentation is widely used to dispose of sewage sludge at wastewater treatment plants (WWTPs), due to production of renewable energy in the form of biogas. Antibiotics present in wastewater may accumulate in a sewage sludge. The aim of the present study is to investigate the impact of three antibiotics from different classes in three different doses on methane production from sewage sludge. For this purpose, metronidazole (MET), amoxicillin (AMO), and ciprofloxacin (CIP) are individually added to anaerobic reactors with sewage sludge collected from municipal WWTP. The antibiotics’ highest concentration (1024 mg kg?1 of AMO; 512 mg kg?1 of MET and CIP) lowers methane production and methane content in biogas. MET exerts the most marked effect and lowers methane production to 36.8 ± 3.7 mL CH4 kg?1 volatile solids. Tested antibiotics probably inhibit methanogenic archaea, which results in volatile fatty acids (VFAs) accumulation. Addition of MET results in accumulation of many kinds of VFAs with the highest concentration of acetic acid (17.52 ± 1.85 g L?1). The addition of of AMO results in accumulation of butyric acid only (253.00 ± 15.89 g L?1). However, addition of CIP results in accumulation of mainly acetic acid (7.58 ± 0.82 g L?1) and isovaleric acid (2.01 ± 0.41 g L?1). Next, synergistic effect of these antibiotics in a low concentration of 16 mg kg?1 of AMO, 8 mg kg?1 of MET, and 2 mg kg?1 of CIP is measured in semi‐continuous conditions and causes inbibition of methane production and accumulation of VFAs. 相似文献
35.
Marcin Jagoda Miłosława Rutkowska Katarzyna Kraszewska Czesław Suchocki 《Studia Geophysica et Geodaetica》2018,62(4):586-595
The planet Earth is continuously changing in time, so there are phenomena that require continuous observation, including tidal parameters. The main goal of this study is to analyze time changes of the Love potential tidal parameters. This paper concerns an analysis of the estimated Love numbers k for the second and the third degree tides (numbers k2 and k3), associated with the tide variations of the satellite motion. The measured data used for determining the parameters k2, k3 were conducted within the period of January 1, 2014 until July 1, 2016 by LAGEOS-1 and LAGEOS-2 satellites. The results were compared with our previous determination of these parameters from LAGEOS data during the period from January 1, 2005 until July 1, 2007 to examine whether any systematic differences and time evolution occur. The adjusted values for k2 equalling 0.29842 ± 0.00008 and k3 equalling 0.0901 ± 0.0034 are discussed and compared with the nominal values given in International Earth Rotation and Reference Systems Service standards. The differences between the k2 and k3 values obtained for the time interval 2005.0–2007.5 and the results for 2014.0–2016.5 interval are –0.00288 for k2 and 0.0042 for k3. The obtained differences in the k2 and k3 values may indicate their evolution in time. 相似文献
36.
Acta Geotechnica - The popularity of the elasto-plastic Hardening Soil (HS) model is based on simple parameter identification from standard testing and empirical formulas. The HS model is... 相似文献
37.
Stable 18O and 13C isotope records of Viviparus diluvianus (Kunth, 1865) shells from Holsteinian (MIS 11) lakes of eastern Poland as palaeoenvironmental and palaeoclimatic proxies 
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下载免费PDF全文 Marcin Szymanek Krzysztof Bińka Jerzy Nitychoruk 《Boreas: An International Journal of Quaternary Research》2016,45(1):109-121
The oxygen and carbon stable isotope composition of Viviparus diluvianus shells was determined in the palaeolakes of the Holsteinian interglacial (MIS 11) in eastern Poland: the Ortel Królewski, Hrud, Ossówka, Roskosz and Szymanowo lakes. The occurrence of V. diluvianus covers the Taxus zone, the so‐called intra‐interglacial cooling period (Pinus‐Larix zone), the climatic optimum (Carpinus‐Abies zone) and the post‐optimal period with an undefined pollen zone. The isotope record of V. diluvianus shells allowed palaeoclimate and palaeoenvironmental reconstructions. δ18O and δ13C vary from −8.7‰ in the post‐optimal period to −4.8‰ in the optimal period, and from −10.6‰ at the beginning of the Taxus zone to −4.2‰ at the climatic optimum, respectively. A positive correlation of the isotope curves indicates closed‐water bodies, and only at Roskosz was some occasional overflow inferred. Higher oxygen isotopes correspond to an increase in temperature and/or enhanced evaporation, which is well marked in the Carpinus‐Abies zone, whereas samples enriched in 13C are correlated with periods demonstrating a lower water level and higher productivity in the lakes. Episodes of lake shallowing and dense aquatic vegetation occurred in the Pinus‐Larix zone and during the climatic optimum. The isotope ratios for the climatic optimum significantly exceed those of the other periods, thus pointing to warmer conditions. An estimation of relative changes of average summer temperatures using the δ18O/temperature gradient yielded variation of 1–2 °C within the lakes. Absolute temperature reconstructions indicate the effects of specific local conditions. Hence, V. diluvianus shells offer a reliable proxy in qualitative studies of interglacial lake records. 相似文献
38.
Marcin J. Szumowski Wojciech W. Grabowski Harry T. Ochs III 《Atmospheric Research》1998,45(4):299-326
This paper describes a two-dimensional kinematic framework designed to test warm rain microphysical models. The idealized flow field is based on a case study from the Hawaiian Rainband Project (1990). Analyses of radar and aircraft data collected in convective cells embedded in Hawaiian rainbands are included for model validation. A Cloud Condensation Nuclei (CCN) activation spectrum, a condensational growth equation including the CCN chemical composition, collection efficiencies, and terminal velocities of the growing drops, are all provided. A sample set of figures from the test run with bulk microphysical parameterization illustrates the desired format for comparisons between the detailed model results and for validation of the model output with observations. This simple yet realistic test formulation includes vertical and horizontal advection, and can be used to evaluate microphysical model performance without complexities resulting from dynamical–microphysical interactions in dynamic cloud models. Without such interactions, scientists can focus on key physical processes involved in the formation of warm rain. The accurate representation of these processes in detailed models is essential to successfully simulate the observed evolution of warm precipitating clouds. 相似文献
39.
Here we briefly report on the discovery of a new Fossil‐Lagerstätte locality, Owadów‐Brzezinki quarry (central Poland), which exposes Late Jurassic (Late Tithonian) carbonate sediments with an extremely fossiliferous horizon of lithographic‐type limestones. Numerous specimens of horseshoe crabs were found in association with an enormously rich assemblage of the soft‐shelled bivalves Corbulomima obscura and Mesosaccella sp., the remains of various fishes and marine reptiles, rare ammonites, crustaceans, land insects and pterosaurs. The uniqueness of this new locality lies in its very close stratigraphical relationship to one of the most famous Fossil‐Lagerstätte localities in the world—Solnhofen, in southern Germany, with approximately 2 Ma separating them. Marine and terrestrial creatures lived and died during the Late Jurassic both at Solnhofen (Hybonotum Zone) and in another area (Owadów‐Brzezinki quarry, Zarajskensis Subzone), under closely related environmental conditions. The small palaeogeographical distance separating these two locations enables, for the first time, an effective palaeobiological test of the pace of evolutionary speciation amongst different groups of organisms. 相似文献
40.
Katy Lancaster Mark Birkinshaw Marcin P. Gawro&#;ski Ian Browne Roman Feiler rzej Kus Stuart Lowe Eugeniusz Pazderski Peter Wilkinson 《Monthly notices of the Royal Astronomical Society》2007,378(2):673-680
We present 30-GHz Sunyaev–Zel'dovich (SZ) observations of a sample of four galaxy clusters with a prototype of the One Centimetre Receiver Array (OCRA-p) which is mounted on the Torun 32-m telescope. The clusters (Cl 0016+16, MS 0451.6–0305, MS 1054.4–0321 and Abell 2218) are popular SZ targets and serve as commissioning observations. All four are detected with clear significance (4 –6σ) and values for the central temperature decrement are in good agreement with measurements reported in the literature. We believe that systematic effects are successfully suppressed by our observing strategy. The relatively short integration times required to obtain these results demonstrate the power of OCRA-p and its successors for future SZ studies. 相似文献