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Albert Maucher 《Mineralium Deposita》1970,5(2):193-198

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Yearly evolution of Euro-Atlantic weather regimes and of their sub-seasonal predictability     

Cortesi  Nicola  Torralba  Ver&#;nica  Lled&#;  Lloren&#;  Manrique-Su&#;&#;n  Andrea  Gonzalez-Reviriego  Nube  Soret  Albert  Doblas-Reyes  Francisco J. 《Climate Dynamics》2021,56(11):3933-3964

It is often assumed that weather regimes adequately characterize atmospheric circulation variability. However, regime classifications spanning many months and with a low number of regimes may not satisfy this assumption. The first aim of this study is to test such hypothesis for the Euro-Atlantic region. The second one is to extend the assessment of sub-seasonal forecast skill in predicting the frequencies of occurrence of the regimes beyond the winter season. Two regime classifications of four regimes each were obtained from sea level pressure anomalies clustered from October to March and from April to September respectively. Their spatial patterns were compared with those representing the annual cycle. Results highlight that the two regime classifications are able to reproduce most part of the patterns of the annual cycle, except during the transition weeks between the two periods, when patterns of the annual cycle resembling Atlantic Low regime are not also observed in any of the two classifications. Forecast skill of Atlantic Low was found to be similar to that of NAO+, the regime replacing Atlantic Low in the two classifications. Thus, although clustering yearly circulation data in two periods of 6 months each introduces a few deviations from the annual cycle of the regime patterns, it does not negatively affect sub-seasonal forecast skill. Beyond the winter season and the first ten forecast days, sub-seasonal forecasts of ECMWF are still able to achieve weekly frequency correlations of r = 0.5 for some regimes and start dates, including summer ones. ECMWF forecasts beat climatological forecasts in case of long-lasting regime events, and when measured by the fair continuous ranked probability skill score, but not when measured by the Brier skill score. Thus, more efforts have to be done yet in order to achieve minimum skill necessary to develop forecast products based on weather regimes outside winter season.

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Rotational distortion of polytropes by analytic approximation,III     

Albert P. Linnell 《Astrophysics and Space Science》1981,76(1):61-72

Paper II of this series was less rigorous than desirable, particularly in the fitting of internal and external potentials. A method is developed in this paper properly to fit the external and internal potentials on the distorted configuration boundary. Displacement of the fiting radius from the radius of a nonrotating configuration in general changes the distorted boundary location by an insignificant amount.A comparison of this theory with the numerical integrations of James (1964) shows excellent agreement to at least an angular velocity equalling 70% of critical rotation. The comparison is for polytropic indices of 1.0, 1.5, 2.0 and 3.0.  相似文献   

Diluviale Bodenfrosterscheinungen am Niederrhein     

Albert Steeger 《International Journal of Earth Sciences》1944,34(7-8):520-538

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Mixed carbonate-siliciclastic infilling of a Neogene carbonate shelf-valley system: Tampa Bay, West-Central Florida     

David S. Duncan  Stanley D. Locker  Gregg R. Brooks  Albert C. Hine  Larry J. Doyle 《Marine Geology》2003,200(1-4):125-156

The shelf-valley system underlying Tampa Bay, Florida’s largest estuary, is situated in the middle of the Neogene carbonate Florida Platform. Compared to well-studied fluvially incised coastal plain valley systems, this shelf-valley system is unique in its karstic origin and its alternating carbonate-siliciclastic infill. A complex record of sea-level changes, paleo-fluvial variability and marine processes have controlled the timing and mechanisms of this ‘compound’ shelf-valley infill. A dense grid of high-resolution, single-channel seismic data were collected at the mouth of Tampa Bay, in an attempt to define this stratigraphy, determine the controls on deposition, and define the underlying structure of this shelf-valley system. The seismic data were correlated with nearby wells and boreholes for lithologic and age control. Sequence stratigraphic methods were incorporated in order to develop an integrated chronostratigraphy for the depositional infilling of the shelf-valley system. Five seismic sequences were identified. Sequence boundaries generally show erosional truncation and karstification, with downlap of overlying sequences. Structure contour and isopach maps indicate that the Tampa Bay shelf-valley system has remained in essentially the same location since its formation in the early Miocene, although the provenance of sedimentary infill has changed. This change is due to increasing amounts of siliciclastic material during the Neogene. Seismic facies interpretations indicate lower-energy, northward prograding deposition dominated by predominantly carbonate sediments within the lowest Sequence A. Higher energy, siliciclastic fluvio-deltaic deposition within sequences B and C originates to the east and northeast of the shelf-valley system related to a Pliocene pulse of sedimentation onto the Florida Platform. Finally, marine processes (longshore transport, ebb-tidal delta formation) dominate the upper two sequences (D and E), reworking these siliciclastic sediments into a spatially mixed carbonate-siliciclastic depositional setting.  相似文献   

Diel changes in food and feeding of small gadoids on a coastal bank     

Albert  Ole Thomas 《ICES Journal of Marine Science》1995,52(5):873-885

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A turbidity survey of Narragansett Bay     

Hilbert Schenck Jr.  Albert Davis 《Ocean Engineering》1973,2(4):169-178

A turbidity survey of Narragansett Bay, Rhode Island, was made during the summer months of 1971 and included measurements of the attenuation function for scalar irradiance for daylight and the volume attenuation function for white tungsten light at various depths. One hundred and three stations were made at 17 different locations. Variations in the optical parameters were large, one standard deviation at any given location ranging from 7 to 23 per cent of the mean value. This variation was only slightly dependent on the state of the tidal currents, depth of the location, or weather factors. The magnitude of turbidity variations was almost 4-fold over a north-south range of 31 km within the estuary, with clearest water at the southern mouths of the Bay. A good correlation exists between turbidity parameters and Autumn values of suspended-material concentration found by Morton (1967), with both data sets showing highest turbidity and suspended concentrations in the West Passage of the Bay. “Wedges” and “bulges” of clear water were detected throughout the Bay but were most evident at the southern (Atlantic Ocean) end.Although it was not possible to fully define the parameters producing these temporal and geographic variations in estuarine turbidity, it is suggested that knowledge of these parameters can assist those concerned with the physical and biological state of an estuary, as well as divers and photographers plying their trades within its boundaries.  相似文献   

General patterns of circulation, sediment fluxes and ecology of the Palamós (La Fonera) submarine canyon, northwestern Mediterranean     

Albert Palanques  Emilio García-Ladona  Dami Gomis  Jacobo Martín  Marta Marcos  Ananda Pascual  Pere Puig  Josep-Maria Gili  Mikhail Emelianov  Sebasti Monserrat  Jorge Guilln  Joaquín Tintor  Mariona Segura  Antoni Jordi  Simn Ruiz  Gotzon Basterretxea  Jordi Font  Dolors Blasco  Francesc Pags 《Progress in Oceanography》2005,66(2-4):89

Currents, particle fluxes and ecology were studied in the Palamós submarine canyon (also known as the Fonera canyon), located in the northwestern Mediterranean. Seven mooring arrays equipped with current meters and sediment traps were deployed along the main canyon axis, on the canyon walls and on the adjacent slope. Additionally, local and regional hydrographic cruises were carried out. Current data showed that mean near surface and mid-depth currents were oriented along the mean flow direction (NE–SW), although at 400 and 1200 m depth within the canyon current reversals were significant, indicating a more closed circulation inside the canyon. Mean near-bottom currents were constrained by the local bathymetry, especially at the canyon head. The most significant frequency at all levels was the inertial frequency. A second frequency of about three days, attributed to a topographic wave, was observed at all depths, suggesting that this wave was probably not trapped near the bottom. The current field observed during the most complete survey revealed a meandering pattern with cyclonic vorticity just upstream from and within the canyon. The associated vertical velocity ranged between 10 and 20 m/day and was constrained to the upper 300 m. This latter feature, together with other computations, suggests that during this survey the meander was not induced by the canyon but by some kind of instability of the mean flow.In the canyon, suspended sediment concentration, downward particle fluxes, chlorophyll and particulate C and N were significantly higher up-canyon from about 1200 m depth than offshore, defining, along with the different hydrodynamics, two canyon domains: one from the canyon head to about 1200 m depth more affected by the canyon confinement and the other deeper than 1200 m depth more controlled by the mean flow and the shelf-slope front. The higher near-bottom downward total mass fluxes were recorded in the canyon axis at 1200 m depth along with sharp turbidity increases and are related to sediment gravity flows. During the deployment period, the increase in downward particle fluxes occurred by mid-November, when a severe storm took place. On the canyon walls at 1200 m depth, suspended sediment concentrations, downward particle fluxes, chlorophyll and particulate C and N were higher on the southern wall than on the northern wall inversely to the current’s energy. This could be caused by an upward water supply on the southern canyon wall and/or the mean flow interacting with the canyon bathymetry. In the swimmers collected by the sediment traps, the dominant species was an elasipod holothurian, which has not been recorded in other canyons or elsewhere in the Mediterranean, indicating particular speciation.  相似文献   

Sectoral scope and colocalisation of Spanish manufacturing industries     

Marta R. Casanova  Vicente Orts  José M. Albert 《Journal of Geographical Systems》2017,19(1):65-92

In this paper, we use distance-based methods, specifically a slight variation of Ripley’s K function and a bivariate generalisation of this function, to explore the detailed location pattern of the Spanish manufacturing industry, the scope of localisation and the tendency towards colocalisation between horizontally and vertically linked industries. To do so, we use micro-geographic data, considering a narrowly defined industry classification. Our results show heterogeneous location patterns, but with a significant tendency towards localisation. The sectoral scope is very sensitive to the degree of homogeneity of the activities in each sector. The more homogeneous the activities in a specific sector are, the more similarities we find in the spatial location patterns among its industries. Finally, although the patterns of colocalisation detected are sensitive to the counterfactuals used, between 20 and 48% of the pairs of industries with strong input–output linkages considered in this study show a significant tendency to colocalisation, and among them 74% are vertically linked industries.  相似文献   

Die kurzwellige Strahlung von Sonne und Himmel auf verschieden orientierte und geneigte Flächen     

Karin Schram  J. C. Thams 《Theoretical and Applied Climatology》1967,15(1-2):99-126

Zusammenfassung In Locarno-Monti am Alpensüdfu? wurde w?hrend zwei Jahren die kurzwellige Strahlung von Sonne + Himmel (Globalstrahlung) auf eine horizontale, je eine um 30° bzw. 60° nach Süden und je eine um 30° nach Osten bzw. Westen geneigte Auffangfl?che mit Solarimetern registriert. Die Tages- und Jahresg?nge der Globalstrahlung zeigen an wolkenlosen Tagen gro?e Unterschiede im Strahlungsgenu? der verschieden orientierten und verschieden geneigten Fl?chen. Im Mittel aller Tage sind diese Unterschiede zwar kleiner, jedoch wegen der gro?en relativen Sonnenscheindauer in Locarno-Monti immer noch sehr ausgepr?gt. Bei vollkommen bedecktem Himmel verschwinden die Unterschiede fast v?llig. Aufgrund der Beziehungen zwischen der Globalstrahlung und der relativen Sonnenscheindauer genügen Parallelmessungen von wenigen Jahren, um daraus klimatologische Mittelwerte der Globalstrahlung auf verschieden orientierte und geneigte Fl?chen berechnen zu k?nnen. Das Verh?ltnis der Strahlung auf geneigte H?nge zu der auf die horizontale Fl?che h?ngt von der Jahreszeit und der Bew?lkung ab. Diese Beziehung kann dazu dienen, bei Kenntnis der Globalstrahlung auf eine horizontale Fl?che jene auf eine geneigte Auffangfl?che zu bestimmen. Schlie?lich wird auf die Bedeutung dieser Untersuchungen für die praktische Meteorologie hingewiesen.

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Summary For a two years' period the total (short wave) radiation of sun and sky falling on a horizontal surface, on southern slopes of 30° and 60° inclination, resp., and on eastern and western slopes of 30° inclination has been recorded with solarimeters at Locarno-Monti (Switzerland). On cloudless days the diurnal and annual variations of the total radiation indicate rather big differences between the radiation falling on the surfaces of different inclination and orientation. Considering the radiation covering all days, these differences are smaller but still distinctly marked because of the high relative duration of sunshine at Locarno-Monti. On overcast days all surfaces receive almost the same amount of radiation. Climatological averages of the total radiation falling on surfaces of different orientation and inclination can be deduced using the relation between the total radiation and the duration of sunshine. The ratio between the radiation falling on inclined planes and the radiation falling on a horizontal surface depends on season and cloudiness. By means of these relations the radiation falling on inclined surfaces can be calculated using the radiation falling on the horizontal surface. Finally the importance of such investigations for applied meteorology is pointed out.

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Résumé Le rayonnement de courte longueur d'onde du soleil et du ciel (rayonnement global) a été enregistré pendant deux ans à Locarno-Monti, au pied sud des Alpes, au moyen de solarimètres présentant différentes orientations. Les surfaces réceptrices étaient respectivement horizontale, inclinées de 30° et 60° vers le sud, ainsi que de 30° vers l'est et l'ouest. Les variations journalières et saisonnières du rayonnement global mettent en évidence les grandes différences d'éclairement des surfaces réceptrices selon leur azimut et leur inclinaison, lors des journées ensoleillées surtout. Ces différences sont plus faibles lorsque l'on prend tous les jours en considération, mais restent cependant bien marquées par suite de la grande durée relative d'insolation à Locarno-Monti; elles disparaissent presque complètement par ciel entièrement couvert. En s'appuyant sur les relations entre le rayonnement global et la durée relative d'insolation, l'on peut calculer des moyennes climatologiques du rayonnement global tombant sur des surfaces d'orientation différente à l'aide de quelques années seulement d'enregistrements parallèles. Le quotient des rayonnements re?us par une pente inclinée et par une surface horizontale dépend de la saison et de la couverture nuageuse. Une fois cette relation connue, il est possible d'évaluer le rayonnement global re?u par une surface inclinée à partir des valeurs relatives à une surface horizontale. Enfin, l'on signale l'importance de ces recherches pour la météorologie appliquée.

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Riassunto A Locarno-Monti al piede meridionale delle Alpi durante due anni fu registrata con solarimetri la radiazione ad onde corte del sole + cielo (radiazione globale) su superfici orizzontale, inclinate di 30° e rispettivamete 60° e rivolte verso sud, nonchè su superfici orizzontale, inclinate di 30° e rivolte verso est, rispettivamente verso ovest. Gli andamenti giornaliero ed annuale della radiazione globale mostrano nei giorni senza nuvole grandi differenze nella quantità di radiazione ricevuta dalle superfici diversamente inclinate e orientate. Nella media di tutti i giorni tali differenze sono si più piccole, tuttavia sempre ancora ben pronunciate causa l'elevata durata relativa dell'insolazione. Con cielo completamente coperto le differenze scompaiono quasi completamente. In base alle relazioni tra la radiazione globale e la durata relativa dell'insolazione, sono sufficienti misure parallele di soli pochi anni per poter calcolare valori climatologici della radiazione globale su diverse superfici orientate e inclinate. Il rapporto tra la radiazione su pendii inclinati e quella su superfici orizzontale dipende dalla stagione e dalla nuvolosità. Questa relazione può servire, conoscendo la radiazione globale su una superficie orizzontale, a determinare quella su una superficie di ricezione inclinata. Da ultimo viene accennato all'importanza di queste ricerche per la meteorologia pratica.

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