The mantle rock (“laterite”) of the Gold Coast and its origin

Zusammenfassung Der Verwitterungsmantel (Laterit s. l.) der südlichen Goldküste besteht aus Horizonten, die sowohl verschiedene Entstehungsart als verschiedenes Alter haben. Brekzien oder Steinschichten sind unter aridem Klima als Wüstenpflaster entstanden. Zonen chemisch verwitterten Felses, Horizonte von lehmigem Sand (an deren Aufbau Termiten wesentlich beteiligt sind) und Konkretionen haben sich unter feuchtem Klima gebildet. Harte limonitische Oberflächen-Krusten deuten auf progressive Austrocknung hin. Unter diesen drei klimatischen Bedingungen gebildete Horizonte wiederholen sich mehrfach im Verwitterungsmantel der Goldküste. Ein junger, unvollständiger Zyklus ist weit verbreitet, ein älterer Zyklus tritt nur in begrenzten Vorkommen auf, und ein dritter Zyklus ist fast nur noch in aufgearbeiteten, limonitisierten Bruchstücken erhalten. Die wiederholten Klimaschwankungen machen es wahrscheinlich, daß der Verwitterungsmantel zeitlich dem größeren Teil des Quartärs entspricht. Wahrscheinlich können die Ergebnisse auf weit größere Gebiete angewandt werden.     

Daily Weather Observations in Sixteenth-Century Europe

Thirty-two weather diaries written in astronomical calendars in central Europe in the late fifteenth and sixteenth centuries are presented and discussed. Systematic weather observations were promoted by the rise of planetary astronomy and its application in astro-meteorology. The practice of keeping weather diaries spread from Cracow (Poland) to Ingolstadt (Germany) and from there to other universities. The data obtained from these sources provided the backbone for setting up series of precipitation indices for Poland, Germany and Switzerland. Monthly statistics of days with precipitation, snowfall and frost were computed by counting the relevant entries in the most important diaries. The results were compared with either those obtained from instrumental measurements in the same place or with those from modern instrumental measurements in a neighbouring place. The final results show that autumn was considerably colder in the early sixteenth century. April was considerably drier and July was wetter during the period 1508-1531 than during 1901-1960. In order to highlight the impact of weather patterns on grain prices in a year of crisis, the timing of wet and dry spells in southern Poland and southern Germany is compared for the year 1529. Winters became 1.7°C colder from 1564 to 1576 and the month of July tended to be wetter than in 1901-1960. Details noted in the diaries kept between 1585 and 1600 by the astronomers Brahe (near Copenhagen) and Fabricius (in the Ostfriesland region of northwestern Germany) closely agree. It rained more often in June and July and temperatures dropped. The winter months were more frequently dominated by winds from easterly directions, the frequency of snowfall was higher and a deficit occurred in precipitation. This points to a higher frequency of high pressure in the Fennoscandian area with cold air advection from the east or northeast.     

Chemical ozone loss in the Arctic vortex in the winter 1995–96: HALOE measurements in conjunction with other observations

Severe chemical ozone loss has been detected in the Arctic in the winter and spring of 1995–96 by a variety of methods. Extreme reductions in column ozone due to halogen catalysed chemistry were derived from measurements of the Halogen Occultation Experiment (HALOE) on board the Upper Atmosphere Research Satellite in the Arctic vortex. Here, we discuss further aspects of the HALOE observations in the Arctic over this period. Potential problems, both in the data themselves and in the methodology of the data analysis are considered and the reason for the differences between the Arctic ozone losses deduced from HALOE data version 17 and 18 is analysed. Moreover, it is shown that HALOE measurements in the Arctic in winter and spring 1995–96 compare well with observations by other ground-based and satellite instruments.     

Geography of contamination: The location of industrial waste dumps in Catalonia

The handling of the solid industrial waste (SIW) generated in Catalonia is one of the main problems of industrial and territorial policy confronting the public bodies controlling this area of activity. The most recent estimates in this regard indicate that the annual production of SIW is 1,700,000 tons and that only 300,000 tons are treated.In this situation it is usual for a large number of industries to eliminate their SIW furtively, it is common practice to dump waste in various unprepared areas. In this article we present a series of hypotheses which we believe allow us to understand the logic that guides the siting of a large number of these dumps.In the first place we demonstrate the importance of a series of conditions derived from the same industrial logic, to wit, a) the cost of transporting the SIW to the dumps, b) the industrial decentralization process and the metropolitan development of Catalonia, c) vertical integration and the appearance of companies especially dedicated to the elimination of waste and, d) the development of land use through revaluation of the land and greater possibilities for control forces furtive dumps to be sited in more and more distant areas.Secondly, we examine the role of public bodies in this process, concentrating on the characteristics of the legal system and the real effectiveness of urban controls. Finally, in third place, an explanation is given of research carried out in the Barcelona area which shows the importance of the conditions examined above.     

Zur Glazialgeologie der chilenischen Anden

Ohne Zusammenfassung     

Early-Morning Flow Transition in a Valley in Low-Mountain Terrain Under Clear-Sky Conditions

We investigate the evolution of the early-morning boundary layer in a low-mountain valley in south-western Germany during COPS (convective and orographically induced precipitation study) in summer 2007. The term low-mountain refers to a mountainous region with a relief of gentle slopes and with an absolute altitude that remains under a specified height (usually 1,500 m a.s.l.). A subset of 23 fair weather days from the campaign was selected to study the transition of the boundary-layer flow in the early morning. The typical valley atmosphere in the morning hours was characterized by a stable temperature stratification and a pronounced valley wind system. During the reversal period—called the low wind period—of the valley wind system (duration of 1–2 h), the horizontal flow was very weak and the conditions for free convection were fulfilled close to the ground. Ground-based sodar observations of the vertical wind show enhanced values of upward motion, and the corresponding statistical properties differ from those observed under windless convective conditions over flat terrain. Large-eddy simulations of the boundary-layer transition in the valley were conducted, and statistical properties of the simulated flow agree with the observed quantities. Spatially coherent turbulence structures are present in the temporal as well as in the ensemble mean analysis. Thus, the complex orography induces coherent convective structures at predictable, specific locations during the early-morning low wind situations. These coherent updrafts, found in both the sodar observations and the simulation, lead to a flux counter to the gradient of the stably stratified valley atmosphere and reach up to the heights of the surrounding ridges. Furthermore, the energy balance in the surface layer during the low wind periods is closed. However, it becomes unclosed after the onset of the valley wind. The partition into the sensible and the latent heat fluxes indicates that missing flux components of sensible heat are the main reason for the unclosed energy balance in the considered situations. This result supports previously published investigations on the energy balance closure.     

Bandwidth Effects in the 3G Photometric System

Bandwidth effects in the GAIA photometric system 3G are discussed. It is demonstrated that careful account for the bandwidth effects in any proposed GAIA photometric system has to be made, in order to determine the fundamental parameters of heavily reddened stars. This revised version was published online in July 2006 with corrections to the Cover Date.     

Diffuse Interstellar Band at 862 nm as a Reddening Tracer for GAIA

We investigate the plausibility of using diffuse interstellar band at862 nm for tracing interstellar extinction with the ESA's astrometric space mission GAIA. For this purpose we perform numerical tests to simulate the conditions of real observations, covering a wide range of stellar parameters and different amounts of interstellar extinction. Our simulations indicate that with the present Radial Velocity Spectrometer setup the uncertainty in color excess of σ_E(B-V)≤ 0.05 can be achieved only for the interstellar reddening tracers brighter than V ∼ 13. None of the plausible tracers can provide accurate color excesses (σ _E(B-V) ≤ 0.05) at the distances beyond 2 kpc. We therefore conclude that with the currently planned instrumentation onboard GAIA this method can not be used as a stand-alone approach for probing interstellar extinction on the Galactic distance scales within the framework of the GAIA mission. This revised version was published online in July 2006 with corrections to the Cover Date.