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Researchers’ fame in most scientific fields is closely linked to their publishing capacity, both in terms of quantity and quality. In GIScience, as in other fields, this situation demands that the researcher evaluate and to be very familiar with the scientific journals in which they could publish. Some specialized journals (e.g. Journal of Citation Reports or JCR) are devoted to ranking these reviews according to various methods and criteria. Compared to other scientific communities, GIScience is relatively new and constantly evolving. Therefore, the journals of this field do not benefit from any real formal ranking yet. The objective of this paper is to present the process and results of a study aimed at addressing this gap. More specifically, the challenge is to elaborate an importance ranking of the scientific journals in the field of GIScience. To do so, both a qualitative (Delphi study carried out with 40 international experts) and a quantitative (JCR impact factor) approach has been implemented. This triangulation method leads to an early global ranking of the journals of this field. 相似文献
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Two cores were recovered in the southeastern part of Lake Shkodra (Montenegro and Albania) and sampled for identification of tephra layers. The first core (SK13, 7.8 m long) was recovered from a water depth of 7 m, while the second core (SK19, 5.8 m long) was recovered close to the present‐day shoreline (water depth of 2 m). Magnetic susceptibility investigations show generally low values with some peaks that in some cases are related to tephra layers. Naked‐eye inspection of the cores allowed the identification of four tephra layers in core SK13 and five tephra layers in core SK19. Major element analyses on glass shards and mineral phases allowed correlation of the tephra layers between the two cores, and their attribution to six different Holocene explosive eruptions of southern Italy volcanoes. Two tephra layers have under‐saturated composition of glass shards (foiditic and phonolitic) and were correlated to the AD 472 and the Avellino (ca. 3.9 cal. ka BP) eruptions of Somma‐Vesuvius. One tephra layer has benmoreitic composition and was correlated to the FL eruption of Mount Etna (ca. 3.4 cal. ka BP). The other three tephra layers have trachytic composition and were correlated to Astroni (ca. 4.2 cal. ka BP), Agnano Monte Spina (ca. 4.5 cal. ka BP) and Agnano Pomici Principali (ca. 12.3 cal. ka BP) eruptions of Campi Flegrei. The ages of tephra layers are in broad agreement with eight 14C accelerator mass spectrometric measurements carried out on plant remains and charcoal from the lake sediments at different depths along the two cores. The recognition of distal tephra layers from Italian volcanoes allowed the physical link of the Holocene archive of Lake Shkodra to other archives located in the central Mediterranean area and the Balkans (i.e. Lake Ohrid). Five of the recognised tephra layers were recognised for the first time in the Balkans area, and this has relevance for volcanic hazard assessment and for ash dispersal forecasting in case of renewed explosive activity from some of the southern Italy volcanoes. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
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The atmospheric energy budget and implications for surface fluxes and ocean heat transports 总被引：2，自引：4，他引：2
Comprehensive diagnostic comparisons and evaluations have been carried out with the National Centers for Environmental Prediction/National
Center for Atmospheric Research (NCEP/NCAR) and European Centre for Medium Range Weather Forecasts (ECMWF) reanalyses of the
vertically integrated atmospheric energy budgets. For 1979 to 1993 the focus is on the monthly means of the divergence of
the atmospheric energy transports. For February 1985 to April 1989, when there are reliable top-of-the-atmosphere (TOA) radiation
data from the Earth Radiation Budget Experiment (ERBE), the implied monthly mean surface fluxes are derived and compared with
those from the assimilating models and from the Comprehensive Ocean Atmosphere Data Set (COADS), both locally and zonally
integrated, to deduce the implied ocean meridional heat transports.
While broadscale aspects and some details of both the divergence of atmospheric energy and the surface flux climatological
means are reproducible, especially in the zonal means, differences are also readily apparent. Systematic differences are typically
∼20 W m−2. The evaluation highlights the poor results over land. Land imbalances indicate local errors in the divergence of the atmospheric
energy transports for monthly means on scales of 500 km (T31) of 30 W m−2 in both reanalyses and ∼50 W m−2 in areas of high topography and over Antarctica for NCEP/NCAR. Over the oceans in the extratropics, the monthly mean anomaly
time series of the vertically integrated total energy divergence from the two reanalyses correspond reasonably well, with
correlations exceeding 0.7. A common monthly mean climate signal of about 40 W m−2 is inferred along with local errors of 25 to 30 W m−2 in most extratropical regions. Except for large scales, there is no useful common signal in the tropics, and reproducibility
is especially poor in regions of active convection and where stratocumulus prevails. Although time series of monthly anomalies
of surface bulk fluxes from the two models and COADS agree very well over the northern extratropical oceans, the total fields
all contain large systematic biases which make them unsuitable for determining ocean heat transports. TOA biases in absorbed
shortwave, outgoing longwave and net radiation from both reanalysis models are substantial (>20 W m−2 in the tropics) and indicate that clouds are a primary source of problems in the model fluxes, both at the surface and the
TOA. Time series of monthly COADS surface fluxes are shown to be unreliable south of about 20∘N where there are fewer than 25 observations per 5∘ square per month. Only the derived surface fluxes give reasonable implied meridional ocean heat transports.
Received: 21 March 2000 / Accepted: 21 June 2000 相似文献
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Benoît Caron Roberto Sulpizio Giovanni Zanchetta Giuseppe Siani Roberto Santacroce 《Comptes Rendus Geoscience》2010,342(6):453-466
We present in this work a tephrostratigraphic record from a sediment piston core (JO 2004) from Lake Ohrid. Five tephra layers were recognised, all from explosive eruptions of southern Italy volcanoes. A multidisciplinary study was carried out, including stratigraphy, AMS 14C chronology and geochemistry. The five tephra layers were correlated with terrestrial proximal counterparts and with both marine and lacustrine tephra layers already known in the central Mediterranean area. The oldest is from Pantelleria Island (P11, 131 ka BP). Other three tephra layers are from Campanian volcanoes: X6, Campanian Ignimbrite-Y5 and SMP1-Y3 (107, 39 and 31 ka BP respectively). The youngest tephra layer corresponds to the FL eruption from Etna Volcano (3.4 ka BP). In three cases these recognitions confirm previous findings in the Balkans, while two of them were for the first time recognised in the area, with a significant enlargement of the previous assessed dispersal areas. 相似文献
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AbstractIn the Moldanubian domain of the Vosges massif (INK France) euperimposition of three distinct crustal units has been attributed to Middle to Late Carboniferous thrusting. Л kinematic analysis of mierostuetures within each unit suggests that extension, following the formation of a Stack of nappes, is actually responsible for the bulk structure of this region. In order to estimate the related exhumation, the temperature and pressure evolution of the lowermost unit is investigated. It is characterised by (i) a prograde evolution within the stability field of kyanite, followed by (ii) a syn-kinematic, 3-4 kbar, near-isothermal decompression before (iii) cooling. Thermal modeling shows that the isothermal decompression may be related to rapid exhumation (> I mm.a-1), which cannot be accounted for by erosion alone. Therefore, exhumation is best explained by extensional processes, possibly related to gravitational collapse of a thickened crust. 相似文献
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David A. Caron Mark R. Dennett Darcy J. Lonsdale Dawn M. Moran Ludmilla Shalapyonok 《Deep Sea Research Part II: Topical Studies in Oceanography》2000,47(15-16)
Microplankton abundances and phytoplankton mortality rates were determined at six stations during four cruises spanning three seasons in the Ross Sea polynya, Antarctica (early spring, Oct.–Nov. 1996; mid-late summer, Jan.–Feb. 1997; fall, Apr. 1997; mid-late spring, Nov.–Dec. 1997). Rates of microzooplankton herbivory were measured using a modified dilution technique, as well as by examining the rate of disappearance of phytoplankton (chlorophyll) in samples incubated in the dark (i.e. grazing in the absence of phytoplankton growth). Strong seasonal cycles of phytoplankton and microzooplankton abundance were observed during the study. Microzooplankton abundance varied by more than three orders of magnitude during the four cruises, and was positively correlated with phytoplankton biomass over the entire data set. Nevertheless, microzooplankton grazing was insufficient to impact significantly phytoplankton standing stocks during most of the experiments performed in this perenially cold environment. Only thirteen out of a total of 51 experiments yielded phytoplankton mortality rates that were significantly different from zero. The highest mortality rate observed in this study (0.26 d−1) was modest compared with maximal rates that have been observed in temperate and tropical ecosystems. Results from twenty experiments examining the rate of decrease of phytoplankton biomass during incubations in the dark agreed quite well with the results of the dilution experiments performed at the same time. The range of mortality rates for the dark incubations was −0.09–0.06 d−1, and the average was essentially zero (−0.01 d−1). That is, chlorophyll concentration was virtually unchanged in samples incubated in the dark for 3 d. A number of factors appeared to contribute to the very low rates of microbial herbivory observed, including low water temperature, and the size and taxonomic composition of the phytoplankton assemblage. Based on our results we conclude that the seasonal, massive phytoplankton blooms observed in the Ross Sea are due, in part, to low rates of removal by microbial herbivores. 相似文献
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Spring water trace element geochemistry: A tool for resource assessment and reconnaissance mineral exploration 总被引：2，自引：0，他引：2
Geochemical data from 151 spring locations within the 37,000 km2 South Nahanni River Basin of the Mackenzie Mountains, Northwest Territories, were analysed as part of a reconnaissance assessment of mineral potential in this large and remote region. Statistical data analyses, graphical methods and strategic grouping of springs according to geochemistry, pH and temperature, were used to identify regions with higher mineralization potential quickly and efficiently. Testing of internal consistency indicates that known world class deposits within the basin are readily detected, but by different methods. As different deposit types have different geochemical signatures a new 3-component approach was developed to analyze trace element data for signatures of mineralisation. Estimation of circulation depth, and therefore maximum potential ore depth, further refines the assessment of economic potential. The depth of circulation of the spring waters ranged from 4.7 km to less than 200 m for the entire dataset. In total, 62 spring locations were identified as having anomalous trace metal content by one or more method (approximately 40% of the dataset). Specifically, 11 spring locations were classified as anomalous by all three methods, and 17 by at least two methods, and 34 by only one method. 相似文献
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Lavender Sally L. Walsh Kevin J. E. Utembe Steven Caron Louis-Philippe Guishard Mark 《Natural Hazards》2022,110(2):1025-1038
Natural Hazards - There are several different estimates of the observed cyclone damage potential of tropical cyclones based on observations of size, intensity and track. For the analysis of climate... 相似文献
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The transition between blueschists and lawsonite-bearing eclogites based on observations from Corsican metabasalts 总被引：2，自引：0，他引：2
Syntectonic eclogites, associated with blueschist parageneses, have recrystallized in metabasalts from eastern Corsica under very low temperatures (420°C). The evolution of these eclogites is recorded by the order of development of metamorphic minerals, as demonstrated by helicitic inclusions of lawsonite and actinolite in Fe-rich garnets, and the occurrence of fibrous Na-pyroxenes in the pressure shadows and cracks of boudinaged garnets, within a foliated matrix composed of glaucophane, Ca---Fe garnets and lawsonite.
A Schreinemakers analysis has been completed on the lawsonite-ferroglaucophane-actinolite-almandine-grossular-ferro-omphacite-chlorite system in a (T,P,μH2O)-space. The resulting three-dimensional relationships are applied to the studied samples. They are consistent with a prograde increase in temperature at low μH2O, producing eclogites from blueschists, and with a subsequent retrogressive decrease in pressure. 相似文献