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681.
682.
Oliver Wetter Christian Pfister Johannes P. Werner Eduardo Zorita Sebastian Wagner Sonia I. Seneviratne Jürgen Herget Uwe Grünewald Jürg Luterbacher Maria-Joao Alcoforado Mariano Barriendos Ursula Bieber Rudolf Brázdil Karl H. Burmeister Chantal Camenisch Antonio Contino Petr Dobrovolný Rüdiger Glaser Iso Himmelsbach Andrea Kiss Oldřich Kotyza Thomas Labbé Danuta Limanówka Laurent Litzenburger Øyvind Nordli Kathleen Pribyl Dag Retsö Dirk Riemann Christian Rohr Werner Siegfried Johan Söderberg Jean-Laurent Spring 《Climatic change》2014,125(3-4):365-367
683.
Oliver Wetter Christian Pfister Johannes P. Werner Eduardo Zorita Sebastian Wagner Sonia I. Seneviratne Jürgen Herget Uwe Grünewald Jürg Luterbacher Maria-Joao Alcoforado Mariano Barriendos Ursula Bieber Rudolf Brázdil Karl H. Burmeister Chantal Camenisch Antonio Contino Petr Dobrovolný Rüdiger Glaser Iso Himmelsbach Andrea Kiss Oldřich Kotyza Thomas Labbé Danuta Limanówka Laurent Litzenburger Øyvind Nordl Kathleen Pribyl Dag Retsö Dirk Riemann Christian Rohr Werner Siegfried Johan Söderberg Jean-Laurent Spring 《Climatic change》2014,125(3-4):349-363
The heat waves of 2003 in Western Europe and 2010 in Russia, commonly labelled as rare climatic anomalies outside of previous experience, are often taken as harbingers of more frequent extremes in the global warming-influenced future. However, a recent reconstruction of spring–summer temperatures for WE resulted in the likelihood of significantly higher temperatures in 1540. In order to check the plausibility of this result we investigated the severity of the 1540 drought by putting forward the argument of the known soil desiccation-temperature feedback. Based on more than 300 first-hand documentary weather report sources originating from an area of 2 to 3 million km2, we show that Europe was affected by an unprecedented 11-month-long Megadrought. The estimated number of precipitation days and precipitation amount for Central and Western Europe in 1540 is significantly lower than the 100-year minima of the instrumental measurement period for spring, summer and autumn. This result is supported by independent documentary evidence about extremely low river flows and Europe-wide wild-, forest- and settlement fires. We found that an event of this severity cannot be simulated by state-of-the-art climate models. 相似文献
684.
A hydrogeological study was conducted in northwestern New Brunswick, Canada, to improve the predictability of fracture-dominated groundwater flow within folded bedrock composed of fine-grained turbidites. Borehole televiewer logging and outcrop mapping, integrated with hydraulic packer tests revealed enhanced hydraulic conductivity associated with northeasterly striking bedding-plane fractures formed during folding and flexural slip. These fractures impart azimuthal anisotropy to the aquifer because of moderately dipping fold limbs. High-angle fractures form a well-developed non-stratabound network, comprising two open fracture sets striking NNE parallel to the current direction of principal stress, and WNW parallel to the direction of principal stress that dominated during the Acadian orogeny. The subset of fractures showing significant oxidation, deemed most important to the groundwater flow system, is dominated by bedding-plane and high-angle fractures striking near-parallel to the maximum principal stress direction, resulting in extensional opening and enhanced hydraulic conductivities. An equivalent porous media model, incorporating anisotropy and varying hydraulic conductivity with depth, indicates that horizontal flow dominates the aquifer with relatively minor exchange between different model layers. These findings have implications for understanding flow directions in the Black Brook Watershed and elsewhere in the Matapédia Basin where fractures formed under similar stress conditions. 相似文献
685.
Shaun Cole Will J. Percival John A. Peacock Peder Norberg Carlton M. Baugh Carlos S. Frenk Ivan Baldry Joss Bland-Hawthorn Terry Bridges Russell Cannon Matthew Colless Chris Collins Warrick Couch Nicholas J. G. Cross Gavin Dalton Vincent R. Eke Roberto De Propris Simon P. Driver George Efstathiou Richard S. Ellis Karl Glazebrook Carole Jackson Adrian Jenkins Ofer Lahav Ian Lewis Stuart Lumsden Steve Maddox Darren Madgwick Bruce A. Peterson Will Sutherland Keith Taylor 《Monthly notices of the Royal Astronomical Society》2005,362(2):505-534
686.
The recent vertical displacement field of the Upper Rhine Graben (URG) located in the tri-national region between Germany, France and Switzerland is investigated using repeatedly measured leveling data. We estimate vertical displacement rates at leveling benchmarks by applying a kinematic network adjustment on more than 40,000 height differences measured by German, French and Swiss surveying agencies. Focusing on an optimal solution for the adjusted rates in the URG area also historical data (measured before 1900) are used, significantly increasing the time span of available measurements and the number of transnational connections between the three countries. To account for inhomogeneities apparent in the database, we apply an iterative variance component estimation within the adjustment procedure, particularly revealing more realistic information on the accuracy of the estimated rates. A special focus within our analysis is put on the statistical testing of gross errors in the observations and model-related errors at benchmarks with non-linear movement. As some of the estimated vertical rates behave significantly different compared to the vertical rates of adjacent benchmarks, a filtering of outliers is applied after the adjustment procedure. The resulting map of linear height changes in an area of 280 km in N–S and 230 km in E–W direction provides detailed insight into the recent vertical displacements of the URG and neighboring regions. In the German part of the study area, it was possible for the first time to consistently constrain an average subsidence rate of 0.5 mm/a ( \(\pm \) 0.2 mm/a) of the Graben interior w.r.t. the Black Forest. In addition to the tectonic displacements, some man-induced surface movements, e.g., caused by oil and groundwater extraction, are observed and discussed. 相似文献
687.
Karl Rinner 《Marine Geodesy》2013,36(3):203-205
The long‐term mean sea level in the Baltic Sea is investigated using the coupled three‐basin model constructed by Carlsson (1997). The model is forced by the observed sea level in the Kattegat, the freshwater supply, horizontal air pressure and density gradients, and the wind stress. Both the seasonal variations and the slope of the mean sea level are investigated and compared with the results of another oceanographic model (Lisitzin, 1962) and a geodetic model (Ekman &; Mäkinen, 1996). In the geodetic model an unofficial height system, NH60, is used, and one part of the investigation is to find out whether this height system is useful for oceanographers. The estimated mean sea level difference between the northern and the southern parts of the Baltic Sea are: 17.1 cm (the present model), 26 cm (Lisitzin's model), and 18.3 cm (the geodetic model). It is concluded that the mean sea level difference between the northern and southern parts of the Baltic Sea is due mainly to horizontal variations of density and air pressure, and that the height system NH60 is suitable for oceanographie applications. 相似文献
688.
Fe and Al oxides distribution in some ultisols and inceptisols of southeastern Nigeria in relation to soil total phosphorus 总被引:3,自引:1,他引:2
Ten highly weathered soils in southeastern Nigeria were sampled from their typical A and B horizons for analyses. The objectives
were to determine the different forms of Fe and Al oxides in the soils and relating their occurrence to phosphate availability
and retention in the soils. The soils are deep and often physically degraded but are well drained and coarse in the particle
size distribution. They are mostly dominated by kaolinite in their mineralogy with very high values of SiO2. The soils are acidic with low soil organic carbon (SOC) contents. The elements in the exchange complex are also low thus
reflecting in the low CEC of the soil. Available phosphorus (P) in the soils are generally low while total P ranged from 157
to 982 mg kg−1 with an overall average of 422 mg kg−1. Total Fe in the soil is highest and their order represented as follows: Fet > Fed > Feox ≥ Fep. The pyrophosphate extractable Fe was always higher in the top soil than in the subsoil and was attributed to the fact that
these forms of Fe are associated with organic matter which is more abundant in topsoil than in subsoil. Like in Fe forms,
the order of Al occurrence could generally be presented as; Alt > Ald > Alox > Alp. More Fe and Al oxides in the soils are strongly crystalline while a small quantity is poorly crystalline Fe forms. The amorphous
forms of both Fe and Al are very low in the soils when compared with the crystalline forms. The oxides that show very strong
affinity to total P are Fed–Feox, Fed, Ald, Fet, Feox and Alox/Ald. To overcome this problem of P retention in the soil, we recommend constant liming of these soils to neutralize them, application
of organic matter and of high dosage of phosphate fertilizer to the soils. 相似文献
689.
QUATERNARY GROWTH FOLDS IN THE JIUXI BASIN AT THE NORTHEASTERN MARGIN OF THE QINGHAI—XIZANG PLATEAUgrants 49732 0 90and 496 0 2 0 36fromtheNSFofChina 相似文献
690.
Karl A. Aiken G. Andre Kong Stephen Smikle Robin Mahon Richard Appeldoorn 《Ocean & Coastal Management》1999,42(12):67
The history, methods, problems and regulation of fishing of the last remaining large queen conch resource in the world, located on a Jamaican fishing bank, are examined. The fishery activities for the queen conch, Strombus gigas Linnaeus are briefly described with the main activities in the industrial sector which produce the bulk of the harvest, which is exported. There are a few large producers harvesting the single major fishing ground of Pedro Bank, southwest of Kingston. These fishers harvested at least 1500 t annually between 1992 and 1998. Management is by licensing, individual quotas and a close season from July to October. Regulations related to CITES are thought to greatly assist in making licensed harvesters provide catch data to the Fisheries Division. The industrial operators have provided funding to undertake stock assessment studies in 1994 and again in 1997. We highlight the focus on management on a participatory consensual approach with meetings with all players in the industry. The conch fishery is thought to be one of the few areas of the Jamaica fishery where there is close and successful collaboration between fishers and the Fisheries Division. It provides an example of how rapid, precautionary, participatory action can provide an adequate basis for management until more definitive scientific information becomes available. The status of the conch fishery is thought to be sustainable at present, once reductions are made to the annual quota. 相似文献