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541.
A three-dimensional, eddy-permitting ocean circulation model with implemented bottom boundary layer model and flux-corrected transport scheme is used to calculate the pathways and ages of various water masses in the Baltic Sea. The agreement between simulated and observed temperature and salinity profiles of the period 1980–2004 is satisfactory. Especially the renewal of the deep water in the Baltic proper by gravity-driven dense bottom flows is better simulated than in previous versions of the model. Based upon these model results details of the mean circulation are analyzed. For instance, it is found that after the major Baltic inflow in January 2003 saline water passing the Słupsk Furrow flows directly towards northeast along the eastern slope of the Hoburg Channel. However, after the baroclinic summer inflow in August/September 2002 the deep water flow spreads along the southwestern slope of the Gdansk Basin. Further, the model results show that the patterns of mean vertical advective fluxes across the halocline that close the large-scale vertical circulation are rather patchy. Mainly within distinct areas are particles of the saline inflow water advected vertically from the deep water into the surface layer. To analyze the time scales of the circulation mean ages of various water masses are calculated. It is found that at the sea surface of the Bornholm Basin, Gotland Basin, Bothnian Sea, and Bothnian Bay the mean ages associated to inflowing water from Kattegat amount to 26–30, 28–34, 34–38, and 38–42 years, respectively. Largest mean sea surface ages of more than 30 years associated to the freshwater of the rivers are found in the central Gotland Basin and Belt Sea. At the bottom the mean ages are largest in the western Gotland Basin and amount to more than 36 years. In the Baltic proper vertical gradients of ages associated to the freshwater inflow are smaller than in the case of inflowing saltwater from Kattegat indicating an efficient recirculation of freshwater in the Baltic Sea. 相似文献
542.
E. Wanner 《Pure and Applied Geophysics》1952,23(1):223-231
Ohne Zusammenfassung 相似文献
543.
Dr. E. Wanner 《Pure and Applied Geophysics》1948,12(3-4):127-129
Summary During the year 1946 the seismic activity in the ?Wallis? (Switzerland) was very high. A series of aftershocks has been registrated
in the epicentre. At the same time the acoustic phenomenon accompanving the shocks has been observed directly. The different
shocks could be classified in two types. The shocks which began as an eyplosion had all a very steep first wavefront (Fig.
2). The shocks which produced the same noise as an approaching heavy car had a very feeble first phase (Fig. 1).
Résumé L'année 1946 fut une période séismique très active dans le Valais. On eut l'occasion d'observer une grande série de répliques dans l'épicentre avec un séismographe transportable. Les phénomènes acoustiques accompagnant ces secousses et observés directement, sont comparés avec les enregistrements séismographiques. Les secousses se manifestant comme eyplosion ont des enregistrements séismiques très typiques. Le front de la première onde des secousses était très raide (Fig. 2), tandis que les secousses dont le bruit émis ressemblait à une voiture roulante ont eu des précurseurs faibles (Fig. 1).相似文献
544.
Joh Wanner 《International Journal of Earth Sciences》1928,18(6):455-456
Ohne Zusammenfassung 相似文献
545.
546.
547.
Lars T. Waser Markus Schwarz 《International Journal of Applied Earth Observation and Geoinformation》2006
Considerable efforts have recently resulted in the development of global land cover data at large spatial scales. The main objective of this study is a comparison of different AVHRR- and MODIS-based forest and land cover products at the scale of the European Alps: a large natural ecosystem that is exposed to both natural environmental threats and human impacts and exploitation. In a first test, the accuracy of land cover products in predicting the overall amount of forest across national boundaries was assessed using national forest inventory statistics. Both variants of forest class combinations resulted in a general overestimation of the forest area. The IGBP 2.0 cover performed best with an overall mean absolute error of 13% and a bias of 0%. In a second test, large-area land cover products were tested for accuracy in predicting 13 aggregated land cover types in a spatially explicit manner using CORINE land cover as reference dataset. Due to data inconsistencies, partly insufficient spatial resolution, steep terrain and land use heterogeneity of the European Alps, only partly satisfactory results were obtained. 相似文献
548.
In biological wastewater treatment, bacteria tend to aggregate by forming flocs, biofilms and even granules. A large part of the floc structure in activated sludge is composed of extracellular polymers. The extracellular polymeric substances (EPS) are mainly responsible for the structural and functional integrity of biofilms/flocs and they are considered to be important for the physico‐chemical properties of activated sludge. This review considers the composition of EPS and proportion between the constituents. Moreover it includes the relationship between the EPS constituents and sludge properties such as sludge retention time, hydrophobicity and surface charge. 相似文献
549.
550.