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1.
Wind measurements which were carried out during the MAP/WINE Campaign in northern Scandinavia between 2 December 1983 and 24 February 1984 are used to derive background winds and monthly as well as winter mean values from the ground up to 90 km altitude. These mean winds compare favourably to the wind field proposed for the revised CIRA 86, which is deduced from satellite measurements. The vertical structure of the zonal monthly means is similar in both data sets during January and February. The winter mean zonal winds are observed to be slightly stronger in the stratosphere and lower mesosphere during the MAP/WINE winter than the satellite winds proposed for CIRA 86. The long term mean meridional winds are in good agreement up to 60 km. They indicate a dominant influence of quasistationary planetary waves up to 90 km and an ageostrophic poleward flow between 60 km and 85 km over northern Scandinavia, which maximizes at 76 km at about 8 m s−1. The observed short term variability of the wind is discussed with respect to a possible impact of saturating gravity waves on the momentum budget of the middle atmosphere.  相似文献   

2.
The MAP/WINE campaign has yielded information on small scale structure and turbulence in the winter mesosphere and lower thermosphere by a number of very different remote and in situ techniques. We have assimilated the data from the various sources and thus attempted to present a coherent picture of the small scale dynamics of the atmosphere between 60 and 100 km. We review physical mechanisms which could be responsible for the observed effects, such as ion density fluctuations, radar echoes and wind corners. Evidence has been found for the existence of dynamic structures extending over distances of the order of 100 km; these may be turbulent or non-turbulent. The results indicate that gravity wave saturation is a plausible mechanism for the creation of turbulence and that laminar flows, sharply defined in height and widespread horizontally, may exist.  相似文献   

3.
A large set of temperature profiles has been obtained in the upper stratosphere and the mesosphere over Europe during the MAP/WINE compaign by the use of different techniques: datasondes and falling spheres launched by metrockets, ground-based OH spectrometers and a Rayleigh lidar. These data have been used to study the large scale variability of the middle atmosphere during the winter 1983–1984. The temperature variations with periods longer than 25 days are clearly related to the succession of minor upper stratospheric warmings observed during this winter. The variations in the period range 10–20 days are at least partially due to westward propagating Rossby waves, of which one mode, with a 12.5 days period, is tentatively identified as the second symmetric mode of the wave number 2.  相似文献   

4.
Water vapor and ozone concentrations measured at mid and high latitudes above Europe during the MAP/WINE Campaign in the winter 1983/1984 are presented. Both water vapor and ozone distributions are found to be variable and structured. On two occasions strong enhancements of mesospheric ozone were recorded, which were probably caused by dynamic effects. The assumption of a photochemical equilibrium for ozone at high latitudes in winter does not appear justified according to the variations measured during MAP/WINE. Water vapor mixing ratios determined in the stratosphere and mesosphere above Scandinavia yield average mixing ratios of near 4 ppmv.  相似文献   

5.
Stratosphere and mesosphere temperatures were measured during four winter months (November–February) at high latitudes (Andøya, ESRANGE) by means of numerous rocket flights during the Energy Budget Campaign 1980 and the MAP/WINE Campaign 1983–1984. They are compared to ground-based OH1 measurements and SSU satellite data. The atmosphere was found to be very active, with several minor and one major stratospheric warming occurring. A harmonic analysis of the temperature oscillations observed is performed and found to be suitable to model the atmospheric disturbances (warmings) to a large extent by superposition of waves with appropriate periods. These periods are of the order of several days and weeks and are thus similar to those of planetary waves. Stratospheric warmings tend to be correlated with mesospheric coolings, and vice versa. This is reproduced by the model, giving details of the phase relationships as they depend on altitude. These are found to be more complicated than just an anticorrelation of the altitude regimes. Strong phase changes occur in narrow altitude layers, with oscillation amplitudes being very small at these places. These ‘quiet layers’ are frequent phenomena and are independently found in the data sets of the two campaigns. They are tentatively interpreted as the nodes of standing waves.The time development of temperature altitude profiles shows strong variations that lead to peculiar features, such as a split stratopause or a near-adiabatic lapse rate in the mesosphere on occasion. The superposition model is able to reproduce these features, too. On one occasion it even shows super-adiabatic temperature gradients in the lower mesosphere for several days. Though this should be taken as an artifact, it nevertheless suggests a considerable contribution of the long period waves to atmospheric turbulence.The many rocket data are also used to determine monthly mean temperature profiles. These are compared to reference atmospheres recently developed for the CIRA (Barnett and Corney, 1985; Groves, 1985). Fair agreement is found, which is much better than with CIRA (1972). This is not true for February 1984, because of the major warming that occurred late in that month. Before this warming took place, atmospheric preconditioning appears to have been present for more than two months.  相似文献   

6.
Abundances of atomic oxygen and ozone have been measured by various techniques over northern Scandinavia during the MAP/WINE campaign in the winter 1983–1984. On 10 February at Kiruna, Sweden, rocket experiments used resonance fluorescence and twin path absorption at 130 nm to measure [O]between 70 and 178 km. Rocket-borne measurements of nightglow at 557.7, 761.9 and 551.1 nm and at 1.27 μm have also been obtained and [O]values derived from the atmospheric band intensities. Ozone abundances between 50 and 90 km have been determined from rocket-borne measurements of the ν3 9.6 μm nightglow intensity from Andøya, Norway, and Kiruna. These have been compared with [O3] measured on the same day from the Solar Mesospheric Explorer satellite, using measurements of dayglow at 1.27 μm, and with results from other rocket launchings in MAP/WINE. The results show evidence of low, perhaps exceedingly low, [O] and below normal [O3] above the mesopause. Below 75 km at night [O3] exceeded earlier and subsequent observations in the campaign. The measurements were made during a minor stratospheric warming, characterised by an offset polar vortex centred near the measurement zone.  相似文献   

7.
As part of the MAP/WINE campaign (winter 1983–1984) and the MAC/SINE campaign (summer 1987) high resolution wind profiles were obtained in the upper mesosphere using the foil cloud technique. Vertical winds were derived from the fall rate of the foil clouds and are used for estimating the momentum fluxes associated with vertical wavelengths shorter than about 10 km. From the ensemble average of 15 observations over an altitude range of 74–89 km we calculate a zonal net momentum flux of +12.6 ± 4.5 m2s−2 in summer. The average of 14 measurements in winter between 73 and 85 km indicates a zonal net momentum flux of −3.7 ± 2.4 m22 s−2.  相似文献   

8.
The morphology of the MAP/WINE winter is examined, principally from ground-based and satellite observations. Winter anomaly is evident, occurring in bursts with a west to east shift in time. Auroral activity, particularly with reference to the times of major rocket salvoes, is generally low, with Andøya to the south of the auroral boundary in most cases. Minor stratospheric warmings, of which 4 occurred, are found to correlate with minima in radio wave absorption. Salvo R1 was launched during one of the minor warmings.Using data from a broad sector of Europe, coupling between the lower thermosphere and mesosphere is seen over large areas. Westerly winds are associated with high absorption (winter anomaly) and reversal to easterly winds with stratospheric warmings and low absorption. It is found possible to select cases, from amongst the MT series of rocket launchings, corresponding to quiet conditions, stratospheric warming, winter anomaly and particle precipitation in the general absence of other effects. Examining D- and lower E-region ionisation profiles for these caes it is found that, compared with a quiet night, the stratwarm night shows the lower E-region to have reduced ionisation. The ionisation ledge is of similar shape in all cases, but occurs over different height ranges. The observed effects all point to transport being a major factor and the need to measure vertical transport over the range of geophysical conditions examined is highlighted.  相似文献   

9.
This paper will show that the colonial project in south Dutch New Guinea was a joint project in which evangelisation, education, ‘civilisation’ and ‘pacification’ were taken up by the Dutch Catholic mission in close collusion with the colonial government. This was also a project in which a few Dutch missionaries deployed many goeroes (teachers) from elsewhere in the Dutch East Indies. These goeroes had an important position assigned to them by the Catholic mission and colonial government in the development of the Papuans and the area. This colonial structure utilised by both Dutch colonial administrators and missionaries has been labelled in the literature as a system of ‘dual colonialism’. Drawing on records held in missionary and colonial archives, the paper explores this dual colonial structure by analysing the roles of Catholic goeroes from the Kei and Tanimbar islands. This is done by taking Felix Driver’s concept of local intermediaries as the point of departure. While this concept makes visible the key role of goeroes, it is not without its issues, which will also be explored.  相似文献   

10.
Partially disarticulated shark vertebrae from the Lower Cretaceous Toolebuc Formation in central Queensland and the Bathurst Island Formation in the Northern Territory provide probable evidence of the Anacoracidae in Australia, and are possibly referable to Pseudocorax. Associated with large shark vertebrae from Canary Station, near Boulia, Queensland, are numerous placoid scales of four primary types which indicate a large pelagic shark. The Canary specimen is one of the few Mesozoic sharks known where scales have been found associated with vertebrae. Problems in referring the new shark material to the Anacoracidae and Pseudocorax are discussed. The significance of vertebral structure and scale morphology in Mesozoic shark evolution and ecology is examined. ‘Lamna daviesii’ Etheridge 1888 is considered a nomen dubium as vertebrae of this kind also occur in other genera in the Lamniformes, Orectolobiformes, and Carcharhinidae.  相似文献   

11.
The complexity of the electric properties of the atmosphere, which influences the excitation and propagation of electromagnetic signals generated by lightning discharges, gives rise to a diversity of the typical signal wave forms and amplitudes in the various space-time domains. This causes difficulties and controversies in the interpretation of the experimental data. In geophysical problems of such a kind, considerations accounting for a broadband spectrum are particularly important.In the present paper, lightning induced ULF-VLF fields in the daytime inhomogeneous atmosphere and D-region of the ionosphere above the thundercloud are analyzed for a standard model of the vertical return stroke. The developed analytical approach makes it possible to unite the canonical model of the electromagnetic radiation into a free-half-space, the discharge (ELF-VLF spectrum) and ‘post-discharge’ (ULF spectrum) low-frequency models and to clarify the temporal scales in the mechanism of lightning coupling with the atmosphere and low ionosphere with respect to the local relaxation time, discharge characteristic time scales and observer location.  相似文献   

12.
With the help of incoherent scatter (EISCAT) data the thermodynamics and electrodynamics of the auroral E-region north east of Andøya Rocket Range has been investigated between 1740 UT and 2040 UT on 31 January 1984. This time period covers the D salvo of MAP/WINE and the EISCAT incoherent scatter data comprise a useful supplement to interpret the rocket data. Good agreement has been found between the EISCAT temperatures and those derived from mass spectrometer data. Neutral wind velocity estimates from EISCAT and from a falling sphere rocket experiment are in satisfactory agreement for the zonal wind component, but disagree for the meridional component.  相似文献   

13.
As plans for expanding fossil fuel infrastructure continue to ramp up despite threats to the planet, how are geographers to address the criminalisation and prosecution of peaceful acts of defending earth, water and land? Reflecting on a courtroom ethnography and debates spanning legal geography, political ecology and social movements studies, this article explores embodied struggles around oil, ‘justice’ and geographies of caring – discussing how Indigenous youth, grandmothers in their eighties and others were convicted of ‘criminal contempt’ for being on a road near an oil pipeline expansion project. The project (“Trans Mountain Pipeline Expansion”) was created to transport unprecedented levels of heavy oil (bitumen) across hundreds of kilometres of Indigenous peoples' territory that was never ceded to settler-colonial authorities in Canada. Focusing on a controversial injunction designed to protect oil industry expansion, the discussion explores the performativity of a judge's exercise of power, including in denying the necessity to act defence, side-lining Indigenous jurisdiction, and escalating prison sentences. Courtroom ethnography offers a unique vantage point for witnessing power at work and vast resources used by state actors to suppress issues fundamental to the United Nations Declaration on Rights of Indigenous Peoples and the Paris Climate Accord. It also provides a lens into the intersectional solidarity and ethics of care among those who dare to challenge colonialism and hyper-extractivism, inviting engagement with multiple meanings of ‘irreparable harm’ at various scales. The article calls for more attention to power relations, values and affects shaping courtroom dynamics in an age in which fossil fuel interests, climate crisis and settler-colonial control over courts are entwined in evermore-complex violent entanglements.  相似文献   

14.
15.
There can be few “bigger” questions than the nature and development of human experience and self-awareness and few better ways to study it than through the changing treatment of the dead over time. Funded by the John Templeton Foundation, the ‘Invisible Dead’ project (Durham University) is exploring diachronic changes in mortuary practices across two regions: Britain and the Levant. In doing so, it uses archaeology as a way to approach fundamental questions about the human condition. This paper explores the principal difficulties faced during the construction of a database for this project and their wider relevance for the development of robust and successful methods for the study of large “mortuary” datasets in the future. It discusses the issues and biases identified within the mortuary record and how the project has sought to mitigate some of these. By adopting a flexible and ultimately expandable approach to data entry and analysis, value can be added to legacy datasets and “grey” literature, allowing us to make comparisons between regions which are both geographically and chronologically distinct.  相似文献   

16.
This article examines Heaney's preoccupation in District and Circle (2006) with international political events during this ‘new age of anxiety’, and how he initially approaches these circuitously through a return to originary, boyhood experiences. Such momentous acts as the attacks of 9/ll, the ‘War on Terror’ and the London bombings are filtered through, juxtaposed with and illuminated by episodes both from the ancient past and Heaney's family history. In attendance, as always, throughout the latest volume is the poet's diverse literary ancestry, a reminder of how his work exemplifies core claims made in ‘Tradition and the Individual Talent’ (1919), where Eliot argues that ‘what makes the writer most acutely conscious of his own place in time’ is ‘the historical sense’, ‘a feeling for the whole of literature’ from Homer onwards. Thus, alongside its detailed address to politics and such crucial literary matters as structure, form and metaphor, the essay repeatedly returns to the intertextual ‘presences’ which haunt and animate Heaney's continuing creative project.  相似文献   

17.
Until recently the ‘heritage industry’ in England overlooked buildings of minority faith traditions. Little has been written about this ‘under-represented’ heritage. Drawing on data from the first national survey of Buddhist buildings in England, we examine the ways in which Buddhist heritage is beginning to be incorporated into the state-funded ‘heritage industry’ as well as how Buddhist communities in England construct heritage through these buildings. First, we draw upon spatial theory in the study of religion to examine three dimensions of minority faith buildings in England and what this tells us about the communities involved: ‘location’ (i.e. the geographical location of the buildings); ‘space’ (i.e. what the buildings are used for and their relationship to local, national and transnational scales); and ‘place’ (i.e. what types of buildings are selected by different communities and why). We then turn to theories of memory that have become popular within the study of religion as well as heritage studies. Religion understood as ‘a chain of memory’ plays an important role in heritage construction via faith buildings, and an analysis of faith buildings, their spatial dimensions and role in ‘memorywork’, helps us think through the dynamics of modern religious belief in a multicultural and post-Christian setting.  相似文献   

18.
This paper focuses on contradictory expressions of memory and belonging of Jews and Palestinians in Israel. It examines the conflicts over planning procedures, which engage such contradictory memories, and belonging at the national and local scales of planning. It explores how the dynamics of power relations can operate differently at each level and can result in planning resolutions, which link in different ways to the constructions of memory and belonging of Jews and Palestinians. The paper begins with an overview of the expressions of belonging and commemoration at the national scale of planning; in the agenda of the Council for the Restoration and Preservation of Historic Sites (CRPHS) in Israel and the rhetoric of the government National Master Plan of Israel (TAMA/35). It challenges this rhetoric in two local planning events: ‘the road and the graveyard’ and the ‘new Jewish neighbourhood and the old Palestinian village’.  相似文献   

19.
An electric field mill is used to measure the vertical component of the geoelectric field at Davis station, Antarctica (68.6°S, 78.0°S, geographic coordinates; 74.6°S magnetic latitude). Local influences on the measurements are determined. Approximately a year of data is subjectively examined to determine periods when the ‘fair-weather’ electric field is expected to be dominant. Using a ‘cumulation of consecutive differences’ method, small intervals of data are combined to determine winter, spring and autumn diurnal ‘fair-weather’ electric field curves. A paucity of intervals not locally influenced precludes determination of a summer diurnal curve.The seasonal-diurnal curves each show a peak between 19 UT and 22 UT that is similar in temporal location and relative magnitude to the global, fair-weather, seasonal diurnal curves (see Reiter, 1992, p. 130). A local influence persists between 03 UT and 10 UT and precludes determination of a magnetospheric influence on the geoelectric field for these data.  相似文献   

20.
《Political Theology》2013,14(2):91-101
Abstract

Has the Church of England, post Faith in the City, become the ‘Marks and Spencer’ of the English urban scene? Many people lament the Church's absence from the high street but few wish to enter the ‘store’, let alone give it their ‘allegiance’ and ‘custom’. As an Anglican priest working in an urban parish, vicar of a large ancient and historically important town-centre Church, and being the first Social Responsibility Officer in the diocese of Peterborough, I fantasize that the Church is both M/S and S/M to want to persist with such an irrelevant parochial structure and outdated theological model of mission. The recently published Urban White Paper and other recent government reports have given an opportunity to consider possible new mission structures that take seriously the complex social layers of a post industrial urban landscape. Renaissance, regeneration and renewal are needed in the structures of the institutional Church and in our thinking of globalized city living.  相似文献   

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