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141.
142.
Conclusions: the Future Relevance of Medical Geography in the Third World This article has deliberately ranged widely and suggested various research themes to which medical geographers interested in health and development might turn their attention. The International Geographical Union Commission on Health and Development established in 1988 suggested a research agenda which includes many of them (see IGU Commission on Health and Development, Circular Letter No. 1 published in GeoJournal 17, 4, 659–660 (1988)). The achievement of even part of such an agenda will call for close international collaboration in research amongst medical geographers and allied disciplines.Increasingly, medical geographers are gaining applied experience in health and health care in the developing world. They are obtaining breadth and depth of knowledge and are now, for example, cogniscant of financial matters such as those involved in the cost explosion in health care worlwide which has particularly sinister implications for the health of Third World countries (Josephg and Phillips 1984). They, too, are now increasingly comfortable in dealing with epidemiological and demographic data. Geographers now no longer focus solely on phenomena such as distance decay or environments for disease. They are aware that human resources, intelligence, aspirations, attitudes and finance are all potent variables influencing successful health care and health in populations.In the future, therefore, the wide-ranging ambit of medical geography will increasingly become relevant to health and health care research in the Third World. Contributions of value will emerge both from those geographers adopting more socio-political stances and those adopting a more empiricist approach. However, it is the holistic nature of geography, with its wide academic links, and the courage of geographers to research in new topics and gain sound understanding of them which will increasingly be recognized. The days of extempore contributions to political, policy and practical debates on health and development are now largely past. Well researched, solid and sound medical geography contributions will, it is hoped, forge ahead.  相似文献   
143.
Summary In an earlier paper (Lindzen, 1986), it was shown that allowing CO2 to vary with snow/sea ice position could lead to a greatly enhanced response in glaciation to 100 K year orbital forcing—even when 20 K year forcing was much stronger. In that model, snow/sea ice position (SSIP) and glaciation were different: the former was the forcing for the latter. However, SSIP and glaciation were not decorrelated. Observations (Berner et al., 1979; Lorius et al., 1985; Neftel et al., 1982) suggest that CO2 may be independently related to both SSIP and glaciation. In the present paper, we allow (in a highly simplified manner) such independent dependence, and show how it alters the earlier results. Briefly, the dependence of CO2 on glaciation can contribute to and even cause a highly enhanced response to the 100 K year component of the forcing. However, the CO2 dependence on SSIP is, on the whole, more effective in this regard. Thus, we expect time series of CO2 to show variation on the faster time scales than does glaciation.With 5 Figures  相似文献   
144.
Summary A numerical prediction model is described which uses the full set of prognostic equations on a domain roughly the size of the United States with a 96 km horizontal grid resolution and six sigma-coordinate levels. Within this grid resides a nested domain of approximately 1000×1000 km with 24 km horizontal resolution. In this nested grid only modifications to the wind field by the better resolved terrain are considered on the lowest two sigma levels. The terrain effects necessitate adjustments in the location of these two sigma levels. Adjusted wind fields cause modifications in the mass and moisture divergence fields, hence in precipitation. These modifications are averaged into the appropriate meteorological fields on the larger grid.The algorithms used by our model allow continuous interaction between both grids with high computational efficiency.The relative importance of synoptic forcing and terrain is demonstrated for the cases of the Big Thompson, Colorado, flood of 1976 and the Cheyenne, Wyoming, flood of 1985.With 15 Figures  相似文献   
145.
Summary The standard equations for the theory of atmospheric tides are solved here by an integral representation on the continuous spectrum of free oscillations. The model profile of back-ground temperature is that of the U.S. Standard Atmosphere in the lower and middle atmosphere, and in the lower thermosphere, above which an isothermal top extends to arbitrarily great heights. The top is warm enough to bring both the Lamb and the Pekeris modes into the continuous spectrum.Computations are made for semidiurnal lunar tidal pressure at sea level at the equator, and the contributions are partitioned according to vertical as well as horizontal structure. Almost all the response is taken up by the Lamb and Pekeris modes of the slowest westward-propagating gravity wave. At sea level, the Lamb-mode response is direct and is relatively insensitive to details of the temperature profile. The Pekeris mode at sea level has an indirect response-in competition with the Lamb mode-and, as has been known since the time of its discovery, it is quite sensitive to the temperature profile, in particular to stratopause temperature. In the standard atmosphere the Lamb mode contributes about +0.078 mb to tidal surface pressure at the equator and the Pekeris mode about –0.048 mb.The aim of this investigation is to illustrate some consequences of representing the tide in terms of the structures of free oscillations. To simplify that task as much as possible, all modifying influences were omitted, such as background wind and ocean or earth tide. Perhaps the main defect of this paper's implementation of the free-oscillation spectrum is that, in contrast to the conventional expansion in the structures of forced oscillations, it does not include dissipation, either implicity or explicity, and thus does not satisfy causality. Dissipation could be added implicity by means of an impedance condition, for example, which would cause up-going energy flux to exceed downgoing flux at the base of the isothermal top layer. To achieve complete causality, however, the dissipation must be modeled explicity. Nevertheless, since the Lamb and Pekeris modes are strongly trapped in the lower and middle atmosphere, where dissipation is rather weak (except possibly in the surface boundary layer), more realistic modeling is not likely to change the broad features of the present results.Symbols a earth's mean radius; expansion coefficient in (5.3) - b recursion variable in (7.4); proximity to resonance in (9.2) - c sound speed in (2.2); specific heatc p in (2.2) - f Coriolis parameter 2sin in (2.2) - g standard surface gravity - h equivalent depth - i ; discretization index in (7.3) - j index for horizontal structure - k index for horizontal structure; upward unit vectork in (2.2) - m wave number in longitude - n spherical-harmonic degree; number of grid layers in a model layer - p tidal pressure perturbation; background pressurep 0 - q heating function (energy per mass per time) - r tidal state vector in (2.1) - s tidal entropy perturbation; background entropys 0 - t time - u tidal horizontal velocityu - w tidal vertical component of velocity - x excitation vector defined in (2.3); vertical coordinate lnp */p 0 [except in (3.8), where it is lnp /p 0] - y vertical-structure function in (7.1) - z geopotential height - A constant defined in (6.2) - C spherical-harmonic expansion coefficient in (3.6) - D vertical cross section defined in (5.6) and (5.9) - E eigenstate vector - F vertical-structure function for eigenstate pressure in (3.2) [re-defined with WKB scaling in (7.2)] - G vertical-structure function for eigenstate vertical velocity in (3.2) [re-defined with WKB scaling in (7.2)] - H pressure-scale height - I mode intensity defined in (8.1) - K quadratic form defined in (4.4) - L quadratic form defined in (4.4); horizontal-structure magnification factor defined in (5.11) - M vertical-structure magnification factor defined in (4.6) - P eigenstate pressure in (3.2); tidal pressure in (6.2) - R tidal state vector in (5.1) - S eigenstate entropy in (3.2); spherical surface area, in differential dS - T background molecular-scale (NOAA, 1976) absolute temperatureT 0 - U eigenstate horizontal velocityU in (3.2); coefficient in (7.3) - V horizontal-structure functionV for eigenstate horizontal velocity in (3.2); recursion variable in (7.3) - W eigenstate vertical velocity in (3.2) - X excitation vector in (5.1) - Y surface spherical harmonic in (3.7) - Z Hough function defined in (3.6) - +dH/dz - (1––)/2 - Kronecker delta; Dirac delta; correction operator in (7.6) - equilibrium tide elevation - (square-root of Hough-function eigenvalue) - ratio of specific gas constant to specific heat for air=2/7 - longitude - - - background density 0 - eigenstate frequency in (3.1) - proxy for heating functionq =c P/t - latitude - tide frequency - operator for the limitz - horizontal-structure function for eigenstate pressure in (3.2) - Hough function defined in (6.2) - earth's rotation speed - horizontal gradient operator - ()0 background variable - ()* surface value of background variable - () value at base of isothermal top layer - Õ state vector with zerow-component - , energy product defined in (2.4) - | | energy norm - ()* complex conjugate With 10 Figures  相似文献   
146.
Summary Surface fluxes of heat, latent heat, and momentum, and entrainment fluxes and vertical motion at the top of the boundary layer have been calculated for limited regions of several mid-latitude ocean storms. Results have been combined to describe distributions of boundary layer processes which are characteristic of such storms. Surface heat fluxes have important effects in the region west of cold or occluded fronts and are relatively unimportant within a band of about 200 km width east of fronts. Entrainment in pre-frontal regions is driven largely by vertical shear at the top of the boundary layer, while in post-frontal regions it is driven largely by surface heat flux. Boundary layers are well defined in regions more than roughly 200 km east or west of fronts; but closer to fronts boundary layers are not well defined due to the combined effects of entrainment, condensation, and vertical motion associated with the distribution of surface stress.With 12 Figures  相似文献   
147.
Summary The Alcsutdoboz-2 (AD-2) core contains 12 magmatic dykes which belong to the Late Cretaceous lamprophyric-carbonatitic association of NE Transdanubia, Hungary. Petrographically, 11 dykes can be considered alkaline lamprophyre (mainly monchiquite), and the remainder might be called carbonatite. The lamprophyre dykes are similar to both alkaline lamprophyres and ultramafic lamprophyres in major element composition, whereas the carbonatite dyke has some features that are similar to carbonatites but others that are dissimilar. Nevertheless, both of the two types of AD-2 dykes possess higher LILE content than the ultramafc lamprophyres and kimberlites, but strongly differ from average carbonatite. Based on the REE pattern, crystal fractionation (mainly of olivine) and separation of a carbonate phase from the parental lamprophyric magma are proposed for genesis of the carbonatite dyke. These characteristics and the compositional zoning of clinopyroxene and mica suggest a complex crystallization history for these dykes. The likeliest origin for the parental lamprophyric melt is through a very small degree of partial melting of metasomatized mantle.
Alkalische Lamprophyre und assoziierte Ganggesteine in Nordost-Transdanubien, Ungarn: die Bohrung Alcsutdoboz-2 (AD-2)
Zusammenfassung Der Kern der Bohrung Alcsutdoboz-2 (AD-2) enthält zwölf magmatische Gänge, die zu der jung-kretazischen Lamprophyr-Karbonatit-Assoziation des nordöstlichen Transdanubiens in Ungarn gehören. Petrographisch gesehen gehören elf Gänge zu den alkalischen Lamprophyren (hauptsächlich Monchiquit), und der Rest kann als Karbonatit bezeichnet werden. Die Lamprophyrgänge sind in ihrer Hauptelementzusammensetzung sowohl alkalischen Lamprophyren wie ultramafschen Lamprophyren ähnlich. Der Karbonatitgang hingegen zeigt Parameter, die denen von Karbonatiten teilweise, aber nicht durchwegs, ähnlich sind. Beide Typen der AD-2-Gänge zeigen höhere LILE-Gehalte als ultramafische Lamprophre und Kimberlite, unterscheiden sich aber deutlich vom durchschnittlichen Karbonatit. Auf der Basis der Seltenen ErdVerteilung, werden Kristallfraktionierung (hauptsächlich von Olivin) und Abtrennung einer Karbonatphase von lamprophyrischen Magma als Vorgänge gesehen, die für die Entstehung der Karbonatit-Gänge relevant sind. Diese Aspekte und die Zonierung der Zusammensetzungen von Klinopyroxen und Glimmer weisen auf eine komplexe Kristallisationsgeschichte dieser Gänge hin. Sehr wahrscheinlich ist die lamprophyrische Ausgangsschmelze durch eine geringfügige teilweise Aufschmelzung von metasomatisiertem Mantel entstanden.
  相似文献   
148.
Summary The western part of the Baltic Sea is a shallow transition area which is characterized by the water exchange between the Baltic and the North Sea. The dynamic processes in this area are forced by sea-level differences between the North Sea and Baltic Sea as well as by local wind and freshwater input. The response patterns are modified by Earth's rotation, bathymetric structures and the alignment of the coast. Series of satellite images permit synoptical views of these pattern and their temporal and spatial development.Sea surface temperature maps derived from infrared data supplied by the National Oceanic and Atmospheric Administration (NOAA) satellite-borne Advanced Very High Resolution Radiometer (AVHRR) are used to show various features like upwelling filaments and eddies.The River Oder discharges into the Pomeranian Bight is the main source of freshwater input into the western Baltic. The variability of this inflow and of the affected coastal seas is being presented in relation to the prevailing meteorological conditions.
Dynamische Besonderheiten in der westlichen Ostsee untersucht anhand von NOAA-AVHRR-Daten
Zusammenfassung Die westliche Ostsee ist ein flaches Übergangsgebiet, das durch den Wasseraustausch zwischen Nord- und Ostsee charakterisiert ist. Die dynamischen Prozesse werden in diesem Gebiet durch Wasserstandsdifferenzen zwischen Nord- und Ostsee, durch den lokalen Wind und die Süßwasserzufuhr getrieben. Die Reaktionsmuster werden modifiziert durch die Erdrotation, die Bathymetrie und den Küstenverlauf.Serien von Satellitendaten gestatten die synoptische Betrachtung dieser Muster und ihrer zeitlichen und räumlichen Entwicklung.Karten der Wasseroberflächentemperatur (SST), abgeleitet aus Infrarotdaten des Advanced Very High Resolution Radiometer (AVHRR), werden genutzt, um verschiedene Strukturen wie Auftrieb, Filamente und Wirbel zu präsentieren. Das Radiometer wird durch die National Oceanic and Atmospheric Administration (NOAA) auf Wettersatelliten betrieben.Der Flußeintrag der Oder in die Pommersche Bucht ist die bedeutendste Süßwasserzufuhr in die westliche Ostsee. Die Veränderlichkeit des Einstroms und die beeinflußten Gebiete sind in Abhängigkeit von den meteorologischen Bedingungen dargestellt.

Recherche du caractéristiques dynamiques en mer Baltique ouest á l'aide de données NOAA-AVHRR
Résumé La partie ouest de la mer Baltique est une zone de transition de profondeur réduite, caractérisée par un échange des eaux entre la mer du Nord et la mer Baltique.Dans cette zone, les processus dynamiques proviennent des différences de niveau de la mer du Nord et de la mer Baltique, des vents locaux et de l'apport en eau douce. Les modèles créés sont modifiés à partir de la rotation terrestre, de la bathymétrie et de la morphologie côtière.Les données satellite permettent d'établir une étude synoptique de ces processus dans l'ensemble de la zone ainsi que leur développement spatio-temporel au moyen de séries.Des cartes de température superficielle (SST) obtenues à partir des données radiométriques infrarouges AVHRR (Advanced Very High Resolution Radiometer) sont utilisées pour présenter des exemples SST caractéristiques de résultats de processus dynamiques de l'ouest de la mer Baltique. Les données radiométriques proviennent du National Oceanic and Atmospheric Administration (NOAA) à partir de satellites météorologiques.La dépendance des développements spatio-temporels de modèles en fonction des conditions météorologiques est discutée à partir de scènes et de séries particulières.Des exemples d'upwelling devant les côtes allemandes, suédoises et polonaises ainsi que des fronts, des filaments et des tourbillons sont présentés.La plus grande partie de l'apport en eau douce à l'ouest de la mer Baltique provient du fleuve Oder, en baie de Poméranie. L'influence des facteurs météorologiques sur la variation de ce déversement et sur les zones influencées est présentée.
  相似文献   
149.
Summary Diagnostic consistency relations are set up for an open valley geometry consisting of two main valley sections and a large tributary. Changing various external model parameters one by one, the reaction of the system is being explored.With 2 Figures  相似文献   
150.
Summary The latitic rock mined at the Gossendorf open pit in the Gleichenberg Volcanic Area of Styria, Austria, has in places been completely altered to various associations of the secondary minerals opal-C/-CT, alunite, kaolinite and montmorillonite. These associations occur in a zonal arrangement, in which the innermost part has been totally altered to opal and moreover has retained its original latitic structure. The results of experimental alteration tests on the latitic rock in open hydrological systems suggest that these secondary minerals and some of the associations observed in the field as well as their zonal distribution, may have been formed by an originally strongly acid solution rich in SO4 2– which, undergoing progressive chemical variation by reaction with the rock, exhibits a chemical gradient. Some of the mineral associations, however, may not be explained by a single alteration process, but must be regarded as the result of multi-stage alteration in which alteration products from weak leaching are super-imposed on alteration products from intense leaching.
Untersuchungen zur hydrothermalen Umwandlung unter dem Einfluß saurer SO4 2–-Lösungen: Diskussion der Bildungsbedingungen der Umwandlungsprodukte der Latite von Gleichenberg, Steiermark, Österreich anhand experimenteller Umwandlungen.
Zusammenfassung Latitische Gesteine sind im Tagbau Gossendorf des Gleichenberger Vulkangebietes, Steiermark, Österreich, z. T. vollständig in verschieden zusammengesetzte Kombinationen der Mineralneubildungen Opal-C/-CT, Alunit, Kaohnit und Montmorillonit umgewandelt. Diese Kombinationen treten in einer zonaren Anordnung auf, wobei der zentrale Bereich vollständig in Opal umgewandelt ist und darüberhinaus noch das ehemalige Latitgefüge aufweist. Experimentelle Umwandlungsversuche mit dem latititschen Gestein im offenen System haben gezeigt, daß diese Neubildungen und einige der beobachteten Kombinationen sowie deren zonare Anordnung durch den Einfluß einer ursprünglich stark sauren SO4 2–-Lösung entstehen können, die sich durch die Reaktion mit dem Gestein chemisch ständig ändert, d. h. einen chemischen Gradienten aufweist. Einige der auftretenden Kombinationen sind jedoch nicht durch ein Umwandlungsgeschehen zu erklären, sondern nur als Ergebnis einer mehraktigen Umwandlung, wodurch sich Umwandlungsprodukte einer starken Auslaugung und die einer schwachen Auslaugung überlagern können.


With 9 Figures  相似文献   
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