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1.
Zusammenfassung Im Horner Becken (Niederösterreich) wurden Kluftmessungen, gravimetrische Aufnahmen und seismische Messungen durchgeführt. In dieser Gegend liegen tertiäre Ablagerungen auf Glimmerschiefern und Phylliten der Böhmischen Masse. Die Arbeit zeigt, daß die Anwendung geophysikalischer Methoden die Grenze und den Verlauf des Grundgebirges mit hoher Genauigkeit feststellen läßt. Weiters ist ersichtlich, daß auch in der Böhmischen Masse die Kluftstellungen dem großräumigen neotektonischen Spannungsfeld entsprechen.
Mit 5 Abbildungen 相似文献
Tectonic, gravimetric, and seismic studies of a depression area of the Bohemian Massif (Lower Austria)
Summary Seismic and gravimetric measurements as well as investigations of the orientation of joints were made in the basin of Horn in Lower Austria. In this region, Tertiary sediments overlie mica-schists and phyllites of the Bohemian Massif. The investigations show that the top of the basement can be found with great accuracy by the geophysical methods employed. It is also seen that the joint orientations in the Bohemian Massif correspond to those expectable from the action of the regional European neotectonic stress system.
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3.
Summary The present article summarizes the essential methods and results of an investigation which was carried out by the paleoclimatological working group of the Geographical Institute of the University of Würzburg from 1983–1989. The aim of this investigation was a seasonal scale reconstruction of the historical climate of Lower Franconia (southern Germany) using instrumental data, narrative sources and harvest records for wine, grain and hay as well as dendrological data (proxy data). Both method and data discussed and regional climate patterns within Franconia are presented.With 2 Figures 相似文献
4.
Z. Berkes 《Theoretical and Applied Climatology》1960,10(4):433-444
Zusammenfassung Unter Verwendung der vonKöppen eingeführten relativen Temperaturen wird die Form der Jahresgänge der Temperatur in Europa untersucht. Für diesen Zweck werden die Änderungen der 30jährigen Normalwerte der Temperatur von Monat zu Monat in Prozenten der Jahresamplitude ausgedrückt.Es wird festgestellt, daß die Frühjahrserwärmung im Mitteleuropa zwischen Januar und April von Südwesten gegen Nordosten fortschreitet und im Siebenbürger Becken verhältnismäßig am stärksten ausgeprägt ist. Die relative sommerliche Erwärmung im Juni ist in der westlichen Ukraine am schwächsten. Das Zentrum der stärksten Abkühlung schreitet von Nordeuropa stufenweise gegen Südwesten fort. Für die Entwicklung der Erwärmungs-und Abkühlungszentren sind außer der Einstrahlung auch advektive und besonders monsunale Einflüsse von Bedeutung.
Mit 6 Textabbildungen. 相似文献
Summary Using the relative temperature introduced byKöppen the shape of the annual variations of temperature in Europe is investigated. To do this, the variations from month to month of the 30-year normal values are expressed in percents of the annual amplitude.It is found that in Central Europe the warming between January and April proceeds from southwest to northeast, and is most pronounced in the Basin of Transylvania (Roumania). Relative heating in June has a minimum in the western Ukraine. The center of cooling proceeds from Northern Europe towards southwest. The development of warming and cooling centers is determined by insolation, advection, and particularly by monsoon effects.
Résumé Etude de la marche annuelle de la température en Europe en utilisant la température relative introduite parKöppen. On exprime dans ce but les variations de mois en mois des moyennes trentenaires en pourcent de l'amplitude annuelle.On constate qu'en Europe centrale le réchauffement printanier, entre janvier et avril, se propage du Sud-Ouest au Nord-Est et se manifeste plus nettement qu'ailleurs sur le Plateau de Transylvanie. Le réchauffement relatif d'été, en juin, est le plus faible en Ukraine occidentale. Le centre du refroidissement maximum se déplace progressivement du Nord de l'Europe vers le Sud-Ouest. Le développement des centres de réchauffement et de refroidissement dépend du rayonnement, mais aussi des processus advectifs, en particulier de ceux qui relèvent de la mousson.
Mit 6 Textabbildungen. 相似文献
5.
Climatic Variability in Sixteenth-Century Europe and its Social Dimension: A Synthesis 总被引：1，自引：1，他引：0
The introductory paper to this special issue of Climatic Change summarizes the results of an array of studies dealing with the reconstruction of climatic trends and anomalies in sixteenth-century Europe and their impact on the natural and the social world. Areas discussed include glacier expansion in the Alps, the frequency of natural hazards (floods in central and southern Europe and storms on the Dutch North Sea coast), the impact of climate deterioration on grain prices and wine production, and finally, witch-hunts.The documentary data used for the reconstruction of seasonal and annual precipitation and temperatures in central Europe (Germany, Switzerland and the Czech Republic) include narrative sources, several types of proxy data and 32 weather diaries. Results were compared with long-term composite tree ring series and tested statistically by cross-correlating series of indices based on documentary data from the sixteenth century with those of simulated indices based on instrumental series (1901-1960). It was shown that series of indices can be taken as good substitutes for instrumental measurements.A corresponding set of weighted seasonal and annual series of temperature and precipitation indices for central Europe was computed from series of temperature and precipitation indices for Germany, Switzerland and the Czech Republic, the weights being in proportion to the area of each country. The series of central European indices were then used to assess temperature and precipitation anomalies for the 1901-1960 period using transfer functions obtained from instrumental records. The statistical analysis of these series of estimated temperature and precipitation anomalies yielded features which are similar to those obtained from instrumental series.Results show that winter temperatures remained below the 1901-1960 average except in the 1520s and 1550s. Springs fluctuated from 0.3°C to 0.8°C below this average. Summer climate was divided into three periods of almost equal length. The first was characterized by an alternation of cool and warmer seasons. The second interval was 0.3°C warmer and between 5 and 6% drier than in the 1901–1960 period. It is emphasized that this warm period included several cold extremes in contrast to the recent period of warming. Summers from 1560 were 0.4°C colder and 4% more humid. Autumns were 0.7°C colder in the 1510s and 20% wetter in the 1570s. The deterioration of summer climate in the late sixteenth century initiated a second period of enlarged glaciers in this millennium (the first having been in the fourteenth century) which did not end until the late nineteenth century.An analysis of forcing factors (solar, volcanic, ENSO, greenhouse) points only to some volcanic forcing. In order to understand circulation patterns in the sixteenth century in terms of synoptic climatology, proxy information was mapped for a number of anomalous months. Attempts to compare circulation patterns in the sixteenth century with twentieth-century analogues revealed that despite broad agreements in pressure patterns, winters with distinct northeasterly patterns were more frequent in the sixteenth century, whereas the declining summer temperatures from the mid-1560s seem to be associated with a decreasing frequency of anticyclonic ridging from the Azores' center of action towards continental Europe. The number of severe storms on the Dutch North Sea coast was four times greater in the second half of the century than in the first. A more or less continuous increase in the number of floods over the entire century occurred in Germany and the Czech lands. The Iberian peninsula and the Garonne basin (France) had the greatest number of severe floods in the 1590s.The analysis of the effects of climate on rye prices in four German towns involved a model that included monthly temperatures and precipitation values known to affect grain production. The correlation with rye prices was found significant for the entire century and reached its highest values between 1565 and 1600. From the 1580s to the turn of the century wine production slumped almost simultaneously in four regions over a distance of 800 kilometers (Lake Zurich to western Hungary). This had far-reaching consequences for the Habsburg treasury and promoted a temporary shift in drinking habits from wine to beer. Peasant communities which were suffering large collective damage from the effects of climatic change pressed authorities for the organization of witch-hunts. Seemingly most witches were burnt as scapegoats of climatic change. 相似文献
6.
Projected shifts of wine regions in response to climate change 总被引：1，自引：1，他引：0
M. Moriondo G. V. Jones B. Bois C. Dibari R. Ferrise G. Trombi M. Bindi 《Climatic change》2013,119(3-4):825-839
This research simulates the impact of climate change on the distribution of the most important European wine regions using a comprehensive suite of spatially informative layers, including bioclimatic indices and water deficit, as predictor variables. More specifically, a machine learning approach (Random Forest, RF) was first calibrated for the present period and applied to future climate conditions as simulated by HadCM3 General Circulation Model (GCM) to predict the possible spatial expansion and/or shift in potential grapevine cultivated area in 2020 and 2050 under A2 and B2 SRES scenarios. Projected changes in climate depicted by the GCM and SRES scenarios results in a progressive warming in all bioclimatic indices as well as increasing water deficit over the European domain, altering the climatic profile of each of the grapevine cultivated areas. The two main responses to these warmer and drier conditions are 1) progressive shifts of existing grapevine cultivated area to the north–northwest of their original ranges, and 2) expansion or contraction of the wine regions due to changes in within region suitability for grapevine cultivation. Wine regions with climatic conditions from the Mediterranean basin today (e.g., the Languedoc, Provence, Côtes Rhône Méridionales, etc.) were shown to potentially shift the most over time. Overall the results show the potential for a dramatic change in the landscape for winegrape production in Europe due to changes in climate. 相似文献
7.
A. Held 《Theoretical and Applied Climatology》1951,2(5):448-461
Zusammenfassung Schon vor etlichen Jahren hat man die Unzulänglichkeiten der früheren Starkregendefinitionen klar formuliert (vor allem in England) und nunmehr durch die Betonung der Häufigkeitn eine verbesserte Definition gefordert. Mit Hilfe von deutschen Auswerteverfahren für Ombrographenregistrierungen wird in vorliegender Arbeit der Versuch unternommen, auf dieser neuen Basis eine für Österreich gültige, aber allgemein vergleichbare Definition der Starkregen zu finden, und es ergibt sich, daß als Starkregen in Österreich ein Regenfall zu bezeichnen ist, der die Intensität eines Idealregens erreicht oder überschreitet, der alle Jahre höchstens einmal in dieser Stärke an jeder Station des betreffenden Gebietes (aber natürlich nicht unbedingt überall gleichzeitig) vorkommen würde (n=1). AlsPlatzregen ist ein Regenfall anzusehen, der die Intensität eines höchstens alle zwei Jahre (n=1/2), und alsstarker Platzregen ein solcher, der die Intensität eines höchstens alle acht Jahre (n=1/8) vorkommenden Regens erreicht bzw. überschreitet. Auf eine formelmäßige Erfassung dieser Grenzkurve wird hier verzichtet, weil solcherart kaum ein einfacher und praktisch verwendbarer Ausdruck gegeben werden könnte; vielmehr werden die zu den festgelegtenn gehörigen Intensitätswerte für vier regengeographisch verschiedene Hauptgebiete Österreichs in einer Tabelle gegeben.
Mit 6 Textabbildungen. 相似文献
Summary Already several years ago the definitions for heavy rainfall were strongly criticized as being insufficient (above all in England) and a better definition with emphasis on the frequency was claimed. Using German evaluation methods for rain-gauge records, this paper makes an attempt of finding a new definition for heavy rainfall being valid particularly for Austria, but comparable generally. It is concluded that, in Austria, a rainfall is to be defined as heavy rain which reaches or surpasses the intensity of an ideal rain occurring with that intensity at most once in a year at every station of the area in question, but not necessarily everywhere at the same time (n=1). A rainfall is considered as downpour if it reaches, respectively surpasses the intensity of a rain occurring at most once every two years (n=1/2), and as heavy downpour a case with an intensity occurring once every eight years at most (n=1/8). A formula of this limit curve is not given as there exists no simple and practically applicable expression for it. Intensity values, however, referring to then given above are presented in a table for four geographical rain areas of Austria.
Résumé Il y a plusieurs années déjà on a souligné (en Angleterre surtout) les insuffisances des anciennes définitions des pluies de grande intensité et on en a suggéré une meilleure en mettant l'accent sur les fréquencesn. Utilisant le procédé allemand de dépouillement des enregistrements d'ombrographes, on tente ici de trouver sur cette nouvelle base une définition des pluies violentes, valable pour l'Autriche, mais permettant une comparaison générale. Il s'ensuit qu'en Autriche on considère comme pluie intense celle qui atteint ou dépasse l'intensité d'une «pluie idéale» qui se produirait au maximum une fois chaque année (n=1) avec cette intensité en chaque station de la région en question (mais pas nécessairement partout en même temps). Unepluie intense ou battante (Platzregen) est celle qui atteint ou dépasse la pluie maximum de deux ans (n=1/2), et unepluie torrentielle (starker Platzregen) celle qui atteint ou dépasse le maximum de huit ans (n=1/8). On renonce ici à préciser numériquement les limites de ces différents cas, car on ne pourrait donner une expression analytique simple et pratique; on se borne donc à présenter sous forme de tableau pour quatre régimes pluvieux d'Autriche les valeurs de l'intensité de pluie correspondant aux différentes valuers den.
Mit 6 Textabbildungen. 相似文献
8.
Climate change is causing important shifts in the suitability of regions for wine production. Fine scale mapping of these shifts helps us to understand the evolution of vineyard climates, and to find solutions through viticultural adaptation. The aim of this study is to identify and map the structural and spatial shifts that occurred in the climatic suitability for wine production of the Cotnari wine growing region (Romania) between 1961 and 2013. Discontinuities in trends of temperature were identified, and the averages and trends of 13 climatic parameters for the 1961 to 1980 and 1981 to 2013 time periods were analysed. Using the averages of these climatic parameters, climate suitability for wine production was calculated at a resolution of 30 m and mapped for each time period, and the changes analysed. The results indicate shifts in the area’s historic climatic profile, due to an increase of heliothermal resources and precipitation constancy. The area’s climate suitability for wine production was modified by the loss of climate suitability for white table wines, sparkling wines and wine for distillates; shifts in suitability to higher altitudes by about 67 m, and a 48.6% decrease in the area suitable for quality white wines; and the occurrence of suitable climates for red wines at lower altitudes. The study showed that climate suitability for wine production has a multi-level spatial structure, with classes requiring a cooler climate being located at a higher altitude than those requiring a warmer climate. Climate change has therefore resulted in the shift of climate suitability classes for wine production to higher altitudes. 相似文献
9.
J. Neumann 《Climatic change》1991,18(4):453-465
Indications of the climate of the Black Sea Region (the region up to about 500 km from the sea) are examined for a period of a few hundred years before and after 0 C.E. Much of the information is obtained from the work of Soviet scientists, some recent discovery regarding ice conditions on a high mountain of Turkey and from archeology of the region.Levels of the Black Sea, the Caspian and that of the large Lake Van were on the rise at the time. The most plausible cause for the level rise of the latter two exitless water bodies is increased precipitation and inflow from the drainage areas; in the Black Sea's case a contributory factor must have been the level rise of the world's oceans. Pollen investigations in the southern European Soviet Union, as well as the large quantities of wine and figs grown on the northern littoral of the Black Sea at the time, suggest that the climate was a little warmer than at present. The pollen investigations intimate a temperature level about 0.5 °C higher than the cold phase around the middle of the first millenium B.C. Support to the aforementioned inference is offered by the recently discovered ice conditions on Mt. Erciyas, Turkey, as they were 2000 years ago. It is also inferred that the precipitation level of the region was, generally, somewhat higher than nowadays.Finally, a brief review is made of glacier, tree-ring density and peatbog data for Europe and North America. They all show that the period around 0 C.E. was relatively warm.In 1986–90 visiting with the Department of Meteorology, University of Copenhagen, Copenhagen, Denmark. 相似文献
10.
O. Svabik 《Theoretical and Applied Climatology》1989,40(4):247-254
Summary Hail defense in Austria is supported by meteorological offices since 1979. Testing the efficiency of these weather modification activities hailpad-networks have been erected 1981/1982 in two target areas (Lower Austria, size 500 sqkm and Styria, size 700 sqkm), with a mean distance of 2 km. All data, i.e. seeding information, hailpad data, crop damage (estimation by the Austrian Hail Insurance) are collected to establish a relation between hail registration and harm on plants. For the period 1981–1987 first results of the target areas are presented. For further investigation on the seeding effect a ten year period with more intensive radar registration will be necessary.
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Zusammenfassung Seit 1979 werden in Österreich bestehende Hagelabwehrorganisationen seitens der Zentralanstalt für Meteorologie und Geodynamik (ZAfMuG) mit betreut. Zur objektiven Registrierung von Hagelschlägen wurden 1981/1982 Hagelmeßnetze mit einem mittleren Stationsabstand von zwei Kilometern errichtet. In Niederösterreich besteht ein Schutzgebiet von 500 km2, in der Steiermark von 700 km2.Die anfallenden Daten, aus Impfeinsätzen, getroffenen Hagelplatten und Kulturschäden (geschätzt von der Österreichischen Hagelversicherungsanstalt) werden an der ZAfMuG gesammelt. Beziehungen zwischen Hagelregistrierungen und Schäden an Pflanzen werden gezeigt. Auf Grund der Erfahrungen bei den Auswertungen zur Periode 1981–1987 wird zur weiteren Beurteilung des Impfeffektes der Einsatz eigener Radaranlagen in einer Folgeperiode empfohlen.
With 7 Figures 相似文献
11.
Zusammenfassung Im ersten Abschnitt werden Einwände gegen die bisherigen Untersuchungen entkräftet. Im zweiten Abschnitt werden neue Belege für die doppelte Schwankung des Großwetters in der gemäßigten Zone während des Sonnenfleckenzyklus erbracht. Es wird gezeigt, daß die Sommer in Neuengland, die 3 bis 1 1/2 Jahre vor einem Fleckenminimum liegen, fast durchweg wärmer als normal sind und alle Hochsommer, die 2,8 bis 1,9 Jahre vor einem Fleckenextrem (Minimum oder Maximum) liegen und in denen weitere solare Bedingungen erfüllt sind, in Mitteleuropa trockener und wärmer als normal sind und übernormalen Luftdruck in Mittel- und Westeuropa aufweisen. Das gleiche gilt in den meisten dieser Jahre auch für den ganzen Sommer und auch für die südlicheren Teile Nordeuropas. Die relative Häufigkeit des Zusammentreffens dieser Großwettererscheinungen mit bestimmten solaren Bedingungen wird als überzufällig erwiesen; die Zusammenhänge werden physikalisch gedeutet.Im dritten Abschnitt wird ein überzufälliger Zusammenhang des Verlaufs der Sonnenflecken vom Vorwinter bis zum Herbst mit dem Temperaturgepräge des Folgewinters in Mitteleuropa dargestellt und erklärt.Im vierten Abschnitt wird aus der zur Erklärung der Doppelschwankung des Großwetters innerhalb des Sonnenfleckenzyklus aufgestellten Hypothese eine logische Folgerung gezogen, die sich auf die Stärke der zonalen Zirkulation in den gemäßigten Breiten in der Höhe der 500 mb-Flächevor einer länger anhaltenden Vermehrung der Sonnenflecken bis zur nächsten Sonnenrotation bezieht. Es wird festgestellt, daß diese rein theoretisch gezogene Schlußfolgerung in der Wirklichkeit mindestens im Winterhalbjahr tatsächlich erfüllt ist, womit ein neues Argument für die Richtigkeit der aufgestellten Theorie des Einflusses der von der Sonne ausgehenden Strahlungsschwankungen auf das Großwetter gewonnen wird. Die Beeinflussung des Großwetters geschieht nicht durch die korpuskularen Strahlungen der Sonne, die auf ionosphärische Vorgänge und dadurch auch auf den Erdmagnetismus wirken, sondern durch länger anhaltende Intensitätsänderungen der Wellenstrahlung, vor allem der ultravioletten Strahlung der Sonne.
Mit 3 Textabbildungen. 相似文献
Summary In the first part objections against the former investigations are refuted. In the second part new arguments are given for the double variation of the large scale weather conditions (Großwetter) in the temperate zone during the sun spot cycle. It is shown that the summers in New England which lie 3 to 1 1/2 years before a sun spot minimum are almost without exception warmer than normal, and all midsummers which lie 2,8 to 1,9 years before a sun spot extremum (minimum or maximum) and in which further solar conditions are satisfied are drier and warmer than normal in Central Europe and show supernormal atmospheric pressure in Central and Western Europe. The same is true during most of the years also for the whole summer and also for the more southern parts of Northern Europe. The relative frequency of meeting of these large scale occurences with certain solar conditions are proved to be beyond chance; the relations are physically interpreted.In the third part a relation beyond chance of the course of the sun spots from the foregoing winter until autumn with the temperature-character of the following winter in Central Europe is described and explained.In the fourth part a logical conclusion is drawn from the hypothesis for explaining the double oscillation of the Großwetter within the sun spot cycle. This conclusion regards to the strength of the zonal circulation in the middle latitudes in the height of the 500 mb-area before a longer increasing of the sun spots until the next rotation of the sun. It is stated that this conclusion is fulfilled in the reality. This is a new argument for the correctness of the used theory concerning the influence of the variations of the sun's radiation upon the Großwetter. This influence is not caused by the corpuscular radiations of the sun which have an effect on the ionospheric occurences and by these also on the terrestrial magnetism, but by assiduous changes of the intensity of the undulatory radiation, especially of the ultra-violet radiation of the sun.
Résumé La première partie de l'article réfute des objections soulevées par les études précédentes. La deuxième partie apporte de nouvelles preuves de la double variation du temps (à grande échelle) de la zone tempérée pendant le cycle des taches solaires. On montre qu'en Nouvelle-Angleterre les étés précédant de 3 à 1,5 ans un minimum de taches sont presque tous trop chauds et que tous les pleins-étés précédant de 2,8 à 1,9 ans un extremum de taches (minimum ou maximum) et pour lesquels d'autres conditions solaires sont remplies sont en Europe centrale trop secs et trop chauds avec pression supra-normale sur le centre et l'Ouest de l'Europe. La même relation existe dans la plupart de ces années également pour tout l'été et dans les régions plus méridionales de l'Europe septentrionale. La fréquence relative de ces conjonctures s'avère comme supérieure à celle du hasard pur; l'auteur en expose les bases physiques.La troisième partie traite d'une relation signifiante entre l'évolution des taches solaires du début de l'hiver à l'automne et l'allure de la température de l'hiver suivant en Europe centrale.Dans la quatrième partie, l'auteur tire de l'hypothèse expliquant la variation double du temps dans l'espace du cycle solaire une conséquence logique se rapportant à l'intensité de la circulation zonale aux latitudes moyennes, à l'altitude de la surface de 500 mb, avant l'augmentation durable des taches solaires jusqu'à la rotation suivante du soleil. Il montre que cette conséquence purement théorique se réalise en fait, au moins pendant le semestre hivernal, et qu'elle fournit ainsi un nouvel argument en faveur de la théorie qui prétend une influence des variations du rayonnement solaire sur la situation météorologique générale. Cette situation n'est pas influencée par le rayonnement corpusculaire du soleil qui intervient dans les phénomènes ionosphériques et dans le magnétisme terrestre, mais bien par les variations à longue période du rayonnement ondulatoire, et avant tout de l'ultra-violet solaire.
Mit 3 Textabbildungen. 相似文献
12.
Climate Change and Global Wine Quality 总被引：10，自引：0，他引：10
From 1950 to 1999 the majority of the world's highest quality wine-producing regions experienced growing season warming trends.
Vintage quality ratings during this same time period increased significantly while year-to-year variation declined. While
improved winemaking knowledge and husbandry practices contributed to the better vintages it was shown that climate had, and
will likely always have, a significant role in quality variations. This study revealed that the impacts of climate change
are not likely to be uniform across all varieties and regions. Currently, many European regions appear to be at or near their
optimum growing season temperatures, while the relationships are less defined in the New World viticulture regions. For future
climates, model output for global wine producing regions predicts an average warming of 2 ∘C in the next 50 yr. For regions producing high-quality grapes at the margins of their climatic limits, these results suggest
that future climate change will exceed a climatic threshold such that the ripening of balanced fruit required for existing
varieties and wine styles will become progressively more difficult. In other regions, historical and predicted climate changes
could push some regions into more optimal climatic regimes for the production of current varietals. In addition, the warmer
conditions could lead to more poleward locations potentially becoming more conducive to grape growing and wine production. 相似文献
13.
O. A. Salau 《Theoretical and Applied Climatology》1986,37(4):220-232
Summary This is a temporal and comparative analysis of thunderstorms and some related phenomena in three towns in the northern part of Nigeria.On a diurnal basis, the three stations show both an afternoon and nocturnal maximum with the nocturnal maximum occurring at 0000–0100 LST for all phenomena.Seasonally, while thundery activities peak first in Jos, Kaduna and Zaria in that order, lightning and squalls peak in the reverse order. This implies that for thundery activities, an ample amount of moisture is required while limited moisture is needed for the initiation of lightning and squalls.Compared to Jos and Kaduna, Zaria possesses a higher amplitude for all the three phenomena under consideration. This stems from the fact that Zaria is closer to the centre of the disturbance line generating zone than the other stations.The diurnal cycle of occurrence of thunderstorms and related phenomena results from the diurnal cycle of insolation in the cloudless area in the vicinity of an easterly wave and radiational forcing of the cloudy region of the perturbed area.
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Zusammenfassung Es handelt sich um eine zeitliche und vergleichende Analyse von Gewittern und mit ihnen verbundenen Phänomenen aus drei Städten im nördlichen Teil Nigerias. Im Tagesgang zeigen die drei Stationen ein Nachmittagsund ein Nachtmaximum, wobei das Nachtmaximum für alle Phänomene zwischen 0 und 1 Uhr Lokalzeit auftritt.Im Jahresgang wandert das Maximum der Gewitteraktivität von Jos über Kaduna nach Zaria, während Blitze und Squalls ihr Maximum in umgekehrter Reihenfolge haben. Für Gewitter ist offenbar reichlich Feuchtigkeit notwendig, während für die Entstehung von Blitzen und Squalls geringere Mengen ausreichen.Im Vergleich mit Jos und Kaduna besitzt Zaria für alle drei behandelten Phänomene die höchste Amplitude. Das rührt daher, daß Zaria näher der die Störungslinie erzeugenden Zone liegt als die anderen Stationen.Der Tagesgang der Gewitteraktivität und der anderen Phänomene entsteht durch den Tagesgang der Einstrahlung in der wolkenlosen Zone nahe einer östlichen Welle und durch den Einfluß der bewölkten Gebiete im Störungsbereich.
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14.
Summary The German Front Experiment 1987 was an experimental effort to determine the influence of the European Alps on cold fronts using data collected by aircraft, radar, surface and upper-air systems between October and December 1987. Measurements were concentrated in the Alpine foreland south of Munich and in the Inn valley in Austria. It was a cooperative effort by groups from Austria, Germany and Switzerland. This study briefly recapitulates the conduct of the experiment and the intense observation periods which were carried through. Then it is outlined to what extent the scientific objectives have been achieved. The findings of the experiments are grouped into the following topics: orographically induced frontogenesis, the interaction of foehn and front, orographically trapped gravity currents, flow into valleys and the modification of precipitation by the Alps. 相似文献
15.
Summary In this paper the daily and hourly values of sunshine duration, as well as the spells of virtually sunless days (daily sunshine duration 3.0 hrs) in Crete island are examined for the decade 1971–1980, which has been chosen for homogeneity of the existing observations.We have found that the sunshine duration at meteorological stations on the south side of Crete island exceeds the sunshine duration at the meteorological stations located on the north side of the island, which is attributed to the combination of Crete's relief and the prevalence of the north winds. We have also found that the sunshine duration measured at the meteorological stations on the east side of the island during the cold period of the year (October-March) exceeds the sunshine measured at the meteorological stations on the west side. This excess is attributed to the influence of the moving cyclones of the Mediterranean Sea especially during this season.We also believe that the moving cyclones are responsible for the same picture which appears when we study the virtually sunless spells with 1, 2 or three consecutive days at all the examined meteorological stations, while virtually sunless spells with more than 3 days show a concentration on meteorological stations on the north side of the island which is caused by the ground relief and the north-blowing winds.Finally, we found that virtually sunless spells follow a modified G. Polya distribution which, using theX
2-test, gives a very good fit at the 95% confidence level.
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Zusammenfassung Es werden die tägliche und stündliche Sonnenscheindauer sowie Tage mit kurzer Besonnung (tägliche Sonnenscheindauer 3,0 Stunden) auf Kreta für die Dekade 1971–1980, die aufgrund der Homogenität der Beobachtungen ausgewählt wurde, untersucht.Die Sonnenscheindauer auf der Südseite der Insel übersteigt die auf der Nordseite, was auf das Relief Kretas und die vorherrschenden Nordwinde zurückgeführt wird. In der kalten Jahreszeit (Oktober bis März) übersteigt die Sonnenscheindauer im Osten die im Westen. Dieser Unterschied dürfte auf den zu dieser Zeit starken Einfluß der wandernden Zyklonen im Mittelmeer zurückzuführen sein.Es wird vermutet, daß das vermehrte Auftreten von ein bis drei aufeinanderfolgenden, praktisch sonnenfreien Tagen im Westen auf die gleiche Ursache zurückzuführen ist, während mehr als drei sonnenfreie Tage konzentriert im Norden auftreten, wohl wegen des Reliefs und des Nordwinds.Schließlich wird gezeigt, daß die praktisch sonnenfreien Tage einer modifzierten Polya-Verteilung folgen. EinX 2-Test ergibt eine gute Übereinstimmung mit einem 95% Konfidenzintervall.
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16.
Both supply and demand side changes are necessary to achieve a sustainable food system. However, the weight accorded to these depends on one’s view of what the priority goals are for the food system and the extent to which production systems versus consumption patterns are open to change. Some stakeholders see the problem as one of ‘not enough food’ and focus on the need to sustainably increase supply, while others consider the resource demanding and ‘greedy’ consumption patterns of the Western world as the main problem and emphasize the need to shift diets. In this study global land use and greenhouse gas emissions are estimated for a set of scenarios, building on four ‘livestock futures’ reflecting these different perspectives. These scenarios are: further intensification of livestock systems; a transition to plant-based eating; a move towards artificial meat and dairy; and a future in which livestock production is restricted to the use of ‘ecological leftovers’ i.e. grass from pastures, food waste and food and agricultural byproducts. Two dietary variants for each scenario are modelled: 1) a projected diet following current trends and 2) a healthy diet with more fruits and vegetables and fewer animal products, vegetable oils and sugar. Livestock production in all scenarios (except the baseline scenario) was assumed to intensify to current levels of intensive production in North-Western Europe. For each scenario, several variant assumptions about yield increases and waste reductions were modelled. Results show that without improvements in crop productivity or reductions on today’s waste levels available cropland will only suffice if production of all protein currently supplied by animal foods is replaced by (hypothetical) artificial variants not requiring any land. With livestock intensities corresponding to current ones in North-Western Europe and with yield gaps closed by 50% and waste reduced by 50%, available cropland will suffice for all scenarios that include a reduction of animal products and/or a transition to poultry or aquaculture. However, in the scenario based on an extrapolation of current consumption patterns (animal product amounts and types consumed in proportions corresponding to the current average consumption in different world regions) and with livestock production based on feed from cropland, available cropland will not be enough. The scenario that makes use of pastures for ruminant production and food waste for pigs, uses considerably less cropland and could provide 40–56 kg per capita per year of red meat. However, such a livestock future would not reduce GHG emissions from agriculture on current levels. This study confirms previous research that to achieve a sustainable food future, action is needed on all fronts; improved supply and reduced demand and waste. 相似文献
17.
Results from two air quality models (LOTOS, EURAD) have been used toanalyse the contribution of the different terms in the continuity equationto the budget of ozone, NOx and PAN. Both models cover largeparts of Europe and describe the processes relevant for troposphericchemistry and dynamics. One of the models is designed to simulate episodesin the order of 1–2 weeks (EURAD), the other is focussing on theseasonal scale (LOTOS). Based on EURAD simulations it is found that theatmospheric boundary layer (ABL) in Central Europe during a summer-smogepisode in 1990 acts as a source of ozone, which is partly exported from theproduction region in Central Europe. About 40% of the ozone producedchemically in the ABL is lost from Central Europe due to net transport(large-scale and turbulent), 40% are deposited within the domain. Vertical mass exchange of ozone is dominated by the prevailing subsidenceand averaged vertical mass fluxes are directed downward. Averaged massfluxes of PAN, which has no stratospheric source, are upward in the upperpart of the ABL. The results from LOTOS are discussed for the same episodeand for a two month period (July/August 1990). The budget calculation showlarger chemical production for the LOTOS model compared to EURAD. Therelative importance of deposition and net transport, however, is in the sameorder. Differences between the two-month calculation and the one weekepisode are only important for Western Europe where the chemical production is enhanced by 30% during the summer-smog episode. The dependence ofthe results on initial and boundary values is discussed for ozone on thebasis of a simple sensitivity study with EURAD where ozone in the FT is setto 10 ppb initially. This leads to a reversal in the direction of averagedozone mass fluxes in the upper part of the ABL. 相似文献
18.
The modern steppe zone of Eurasia is an active arena for the blowing of mineral matter out of the land surface and for its incorporation to the global process of exchange of matter and energy. The ploughed soil of the steppe zone used in agriculture annually loses tens of tons of fine earth from each hectare. This reduces the natural fertility of lands and quickens the general degradation of steppe ecosystems. This occurs especially intensively during blocking processes, when a strong anticyclone sets in over southeastern Europe. In this case, the energy wind load on the soil surface increases by one or two orders of magnitude as compared to the normal, and its destruction becomes catastrophic. In the zone where airflows converge in the steppes of the Lower Volga, Caspian region, and Ciscaucasia, wind-blown mineral substances are transported in the storm zone for a distance of 2000 km and are accumulated on the land surface in Central and northwestern Europe. 相似文献
19.
Analysis of lightning-induced forest fires in Austria 总被引：1，自引：0，他引：1
Mortimer M. Müller Harald Vacik Gerhard Diendorfer Alexander Arpaci Herbert Formayer Hartmut Gossow 《Theoretical and Applied Climatology》2013,111(1-2):183-193
Besides human-caused fires, lightning is the major reason for forest fire ignition in Austria. In order to analyse the causes of ignition and to characterise lightning-induced forest fires, fire records were compared with the real appearance of lightning events by using the Austrian Lightning Detection and Information System for the period from 1993 to 2010. A probability was estimated for each forest fire being caused by lightning by using a decision tree and decision matrices based on flash characteristics (e.g. amplitude, time, location). It could be shown that 15 % of documented forest fires were lightning-caused. Nearly all lightning-caused fires were found during the summer months, whereas almost 40 % of all fires occurring from June to August were naturally caused. Most lightning-caused fires took place in the south and east of Austria. Lightning fires were more frequent at higher altitudes and primarily affected conifer forests. The median burned area was lower than that for anthropogenic forest fires. 相似文献
20.
Documentary Evidence on Climate in Sixteenth-Century Europe 总被引：2，自引：0，他引：2
Christian Pfister Rudolf Brázdil Rüdiger Glaser Mariano Barriendos Dario Camuffo Mathias Deutsch Petr Dobrovolný Silvia Enzi Emanuela Guidoboni Oldřich Kotyza Stefan Militzer Lajos Rácz Fernando S. Rodrigo 《Climatic change》1999,43(1):55-110