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1.
This article analyses processes of uneven urbanisation by looking at flood infrastructure. Combining the conceptual frameworks of uneven development with the political ecology of urbanisation, we use flood infrastructure as a methodological device to trace the processes through which unevenness occurs within, but also far beyond, the city of Jakarta, Indonesia. We do this to show how the development of flood infrastructure in Jakarta is shaped by the logic of capitalism through mutually implicated tendencies of socionatural differentiation and equalisation. These processes render waters, resources and labour as similar across places and times to produce different spaces for different populations, within and beyond city boundaries. This theorisation reveals how the urban inequalities (re)produced by flood infrastructure are intimately linked to inequalities (re)produced through the urbanisation of the non‐city.  相似文献   

2.
The middle and upper atmosphere and the ionosphere at high latitudes are studied with the EISCAT incoherent scatter radars in northern Scandinavia. We describe here the investigations of the lower thermosphere and the E-region, and the mesosphere and the D-region. In the auroral zone both these altitude regions are influenced by magnetospheric processes, such as charged particle precipitation and electric fields, which are measured with the incoherent scatter technique. Electron density, neutral density, temperature and composition are determined from the EISCAT data. By measuring the ion drifts, electric fields, mean winds, tides and gravity waves are deduced. Sporadic E-layers and their relation to gravity waves, electric fields and sudden sodium layers are also investigated with EISCAT. In the mesosphere coherent scatter occurs from unique ionization irregularities. This scatter causes the polar mesosphere summer echoes (PMSE), which are examined in detail with the EISCAT radars. We describe the dynamics of the PMSE, as well as the combination with aeronomical processes, which could give rise to the irregularities. We finally outline the future direction which is to construct the EISCAT Svalbard Radar for studying the ionosphere and the upper, middle and lower atmosphere in the polar cap region.  相似文献   

3.
This article explores the coevolution of landscape approaches and geospatial tools in Middle Eastern archaeology. From the first aerial reconnaissance programs, archaeologists recognized the value of a view from above to address overarching human–environmental questions that underpin regional historical narratives. The diversity and density of visible remains in the landscape of the Middle East has required an integrative approach, encompassed in the perspective of landscape as a static artifact, landscape as built features, landscape as a system, and landscape as a dynamic construct, which cuts across modern political boundaries. Recent advances in geospatial tools and datasets have enabled archaeologists to make significant progress on four long-standing questions of how to (1) best document and manage rapidly disappearing ancient landscapes, (2) understand landscape formation processes, (3) identify and interpret economic, environmental, and social influences that result in long-term settlement and land use patterns, and (4) recognize and contextualize the interplay between environment and human agency in the evolution of ancient economies and transformations in socio-organizational complexity.  相似文献   

4.
This paper adopts a geosocial approach to sociopolitical research by thinking with sediment as a forceful mode of terraqueous mobility driven by interactions between dynamic earth systems inflected by social processes. It demonstrates that sediment is an active and vital state of matter, with the potential to erupt into and disrupt human politics. Unpacking sediment as a form of movement challenges assumptions of the earth as a stable platform on which socio-political processes play out. The paper develops its argument through analyses of the Rohingya refugee camps in southeast Bangladesh and a char (sediment) island in the Meghna Estuary to which Bangladesh proposes to relocate the refugees. In the first situation, the sedimentary logics of anticline geology, deforestation and monsoon rains push back against political agendas directed towards constraining refugee movement. In the second, fluvial and oceanic sedimentary dynamics and the post-Holocene volatility of the monsoon throw into doubt the engineering solution proposed by Bangladesh to the political problems the refugee presence poses. Through these examples, the paper adds to literature on how states of matter inflect, exceed, undercut or in other ways interfere with matters of state through their unique, dynamic environmental properties.  相似文献   

5.
ABSTRACT

Management of fluvial flood risk in the UK is undergoing a paradigm shift, with a change in emphasis from solely working with structural defences to considering catchment-based measures which attenuate flood runoff. Natural Flood Management (NFM) is promoted as a method that can reduce flood risk through the alteration, restoration or use of landscape features. Here we highlight the potential to manage runoff locally in the rural landscape using NFM by targeting flow pathways and utilising floodplains and riparian zones. Using two case study examples from the UK, we show that by accumulating dispersed small-scale storage in small catchment areas (<10 km2) can assist in attenuating flood runoff. However, there is currently a lack of evidence of measure effectiveness at larger catchment scales and for managing extreme flood events. Nevertheless, there is a strong evidence base to suggest many of these measures deliver a range of different ecosystem services if installed in the correct location in the landscape.  相似文献   

6.
The formation of citizenship as a concept to define the rights of participation in the formation processes of modern territorial states is well known. But the transnational dimensions of defining citizenship and how to combine national legislations with enlightened universal and natural law rules in the mid-19th century is not very well known. The article aims to explore the transnational discourses on the political, economic and moral rights and duties of the citizen in the pan—European liberal Association Internationale pour le Progrès des Sciences Sociales. During the 1860s, its congresses should serve as a vast commission of enquiry and should eventually lead to a general definition of citizenship in Europe which could be implemented in national legislations. The article shows how the Association Internationale tried to deduce universal moral rules from national legislations and peculiarities by the means of moral or positive social science. In combining moral unity with national and regional diversities, the Association Internationale tried to give an elastic framework for a European civil society in which national subjects should become active citizens.  相似文献   

7.
This paper looks at the ancient Jewish talmudic literature (4th-7th centuries CE) for information about fish and fish products in the ancient world and compares it with information from classical sources and from archaeology. Analysis of the texts show that information about food, and particularly fish and fish products, can be derived from texts originally written as religious regulations and moral narratives. Talmudic textual evidence, backed up by parallel archaeological finds, documents long-distance transport of preserved fish, including what is identified as Nile perch from Egypt and mackerel from Spain. Parallel papyrological evidence testifies to the import of the parrot wrasse. Graeco-Roman allec, a sauce made of macerated tiny fish, is identified by the Palestinian Talmud with tarit terufah, made of tiny chopped fish, and afitz, cf Greek afye, immature fish, often cooked as such. Remains of allec have been found archaeologically in Israel/Palestine. The Palestinian Talmud identifies tarit[a] with tza?ana, one of a trio of strong-smelling Babylonian fish-dishes eaten by the poor: the others are gildana and harsana. The varied material on these discussed here adds to our knowledge of ancient salted and/or fermented fish-dishes. The identification of tza?ana with 9th-to-10th century ?a?na from Baghdad of the Caliphs and 14th-century Cairo appears very likely. Thus tarit/tza?ana/?a?na appears to have been not very appetising processed fish food for the poor in Roman Palestine, Jewish Babylonia, Baghdad of the Abbasid Caliphs and Mamluk Egypt, and it may be identified with allec. The talmudic literature also discusses reasons for failure of the preservation processes, as well as of potentially lethal effects of insufficient preservation.  相似文献   

8.
Data from a chain of seven ionosondes in the range of 56–38 N and 1–38° E geographic coordinates were analysed to illustrate the global and regional behaviour of the mid-latitude F-region for some selected geomagnetic storms that occurred during the solar cycle 21. It was found that there are different spatial scales in the response of the mid-latitude ionosphere to the disturbance in the magnetosphere-ionosphere thermosphere system. The physical mechanisms and processes are discussed in relation to the relevance of various theories in the understanding of the dynamics of ionospheric storms.  相似文献   

9.
Wind fluctuations in the middle atmosphere behave like colored noise processes. They have a continuum of scales without dominant features and a power spectrum density (PSD) that often decays with frequency ƒ as ƒ−β. Spectral index β is generally obtained through least-square fit to PSD estimated by Fourier methods. Graphs of colored noise have fractal plane-filling properties depending on β. An efficient method for finding β using the fractal dimension (D), based on analysis of 1/ƒ noise in galactic X-ray luminosities by McHardy I. and Czerny B., (1987, Nature325, 696), is described. An empirical relation is found between D and β and its validity is confirmed in limiting cases. Then D is obtained from power-law dependence of a length metric L(μ) on scale μ. The method is applied to middle-atmospheric velocity data from the Poker Flat radar in Alaska. Variations of D follow those in β, from an earlier analysis by Bemraet al., (1986, Handbook for MAP20, 216), but show an offset of 0.1–0.2 even after corrections for outliers, gaps, and additive noise. Usefulness of this method for screening data as an aid to spectral analysis is examined.  相似文献   

10.
Stylistic change in Maasai spears is examined in light of their use as symbolic instruments. Importation, selection, use, and abandonment of formal traits in spears are analyzed for pastoralists of Samburu District, Kenya. The ever-changing form of spears helps males to move through a sequence of age grades, where graduation to each new grade changes one's status and social networks. Ethnoarchaeological significance of the Maasai example lies in how and why material styles both aid and reflect interaction between males of varying social status and how change in material styles helps to reinforce relatively stable social roles. Archaeologically, these Maasai socioeconomic processes may serve as analogs for Paleolithic and Mesolithic social structures that exhibited aspects of both egalitarianism and ranking.  相似文献   

11.
Radar and radio measurements have provided detailed information on the dependence of F-region electrodynamic drifts on height, season, solar cycle and magnetic activity. Recently, satellite ion drift and electric field probes have determined the variation of low latitude ionospheric drifts over a large range of altitudes and latitudes. The general characteristics of the quiet time plasma can be explained as resulting from E- and F-region dynamo and interhemispheric coupling processes. The low latitude and equatorial zonal and upward/poleward components of the plasma drift respond differently to geomagnetic activity. Disturbance dynamo effects are responsible for the drift perturbations following periods of enhanced magnetic activity. The prompt penetration of high latitude electric fields to lower latitudes produces large perturbations on the upward/poleward drifts, but has no significant effect on the low latitude and equatorial zonal drifts. A number of processes such as ‘overshielding’, ‘fossil wind’ and magnetic reconfiguration were suggested as being responsible for the direct penetration of high latitude electric fields to lower latitudes. Detailed low latitude and global numerical models were used to study the characteristics of low latitude and equatorial plasma drifts and their response to changes in the polar cap potential drop or in the high latitude field-aligned currents. These models can reproduce the latitudinal variation of the perturbation electric fields and their diurnal variations, but are still unable to account for several aspects of the experimental data as a result of the complexity of the high latitude and magnetospheric processes involved.  相似文献   

12.
Changes in channel morphology that occurred along the Macdonald River between 1949 and 1955 are often cited as an example of catastrophic channel change. However, the question of whether these changes represented one component of a cyclical evolutionary pattern, or a systematic and persistent shift to a new morphologic state remains to be clearly defined, as does the significance of these dramatic channel changes when viewed against the river's longer‐term Holocene history. In this paper, new measurements of the Macdonald River's channel morphology are used to resolve the river's evolution in the ~50 years since these major channel‐altering floods. By 2002, the Macdonald River's bed had narrowed considerably from its 1955 post‐flood maximum due to the construction of a new floodplain surface within the widened channel. In some locations, the 2002 bed width is comparable to that of the pre‐1949 channel. This aspect of the river's evolution follows models of cyclical channel evolution proposed for the region. However, in light of recent research into the river's longer term Holocene evolution, it is clear that other channel changes that occurred in response to the 1949–1955 floods, particularly the 2 metres of river bed aggradation and 7 kilometres down‐valley shift in the thalweg's intersection with mean sea level, are less cyclic in nature. The capacity of coastal rivers to prograde into estuaries, which in turn induces river bed aggradation, can be seen in this case to counteract the incisional tendencies associated with post‐flood channel contraction, such that persistent river bed aggradation occurs.  相似文献   

13.
The neutral dynamic and electrodynamic coupling between high and low latitudes, and the mutual interactions between these two processes, are investigated. For 22 March 1979, when a sudden increase in magnetic activity occurred, we have analyzed the following experimental data: (a) neutral densities and cross-track neutral winds as a function of latitude (0°–80°) near 200 km from a satellite-borne accelerometer; (b) hourly mean H-component magnetic data from the Huancayo Observatory (0.72°S, 4.78°E; dipole geomagnetic coordinates) magnetometer; and (c) hourly mean foF2 measurements from the ionosonde at Huancayo. Comparisons are also made with a self-consistent thermosphere-ionosphere general circulation model and with observationally-based empirical models of winds and density.In concert with the increase in magnetic activity to Kp levels of 5–7, a nighttime (2230 LT) westward intensification of the neutral wind approaching 400 ± 100 ms−1 occurred near the magnetic equator on 22 March 1979, accompanied by a 35% increase in neutral mass density. About 2 h after each of two substorm commencements associated with periods of southward IMF, ∼100γ and ∼200γ reductions in the daytime Huancayo H-component (corrected for ring current effects) are interpreted in terms of ∼0.5 and ∼1.0 mVm−1 westward perturbation electric fields, respectively. An intervening 2-hour period of northward IMF preceded a positive equatorial magnetic perturbation of about 200γ. Time scales for field variations are a few hours, suggesting that processes other than Alfven shielding are involved. Variations in f0F2 (∼ ± 1.0 MHz) over Huancayo are consistent with the inferred electric fields and magnetic variations. Similar equatorial perturbations are found through examination of other magnetic disturbances during 1979.  相似文献   

14.
Nationalism is frequently considered as an extreme, ‘hot’ phenomenon related to often violent nation/state-building processes. Billig’s Banal Nationalism turned the attention to how nationalism is also ‘flagged’ and routinely reproduced in existing states. This article studies the mobilization of these forms of nationalism and suggests that independence is a useful notion in bridging the hot/banal divide and for tracing the ‘hot in the banal’. Whereas for separatist movements independence is primarily a goal aspired to, in existing states independence/sovereignty is used to bring together hot and banal forms of nationalism which are mobilized in reproducing the discourses/practices related to the purported national identity. This paper first outlines a heuristic framework for conceptualizing independence and its key dimensions in relation to hot and banal nationalism as well as state-territory building. Secondly, the paper will study empirically the merit of the notion of independence regarding nationalism research via four themes: (1) the role of independence in Finland’s state/nation-building process, spatial socialization and in mixing hot and banal nationalism; (2) the use of the ‘independence card’ by (nationalist) parties; (3) the mobilization of nationalist practices/discourses in the performativity of Finnish Independence Day; and (4) the resistance that the independence celebrations have incited. This study shows that the idea of independence in this context is inward-looking, draws on Othering, and is flagged in media and spatial socialization (e.g. education) using particular iconographies, landscapes, events, and memories related above all to wars. Rather than expressing hot or banal nationalism these discourses/practices effectively merge the two, challenging any simple dichotomy between them. The performativity of Independence Day in particular displays this blending.  相似文献   

15.
In an analysis of the 200‐year history of flood management in Hungary, I use the advocacy coalition framework and the focusing event literature to examine what policy change occurs and what is learned as a result of experiencing extreme and damaging flood events. By analyzing the policy response to a series of extreme floods (1998–2001) in this newly democratizing nation, I attempt to identify the factors that influenced the occurrence of policy change and policy‐oriented learning. In 2003, Hungary enacted a comprehensive flood management program that included economic development and environmental protection goals, a distinct departure from Hungary's historical structural approach to flood management. However, it is less clear that long‐lasting changes in belief systems about how floods should be managed have occurred. In this analysis, I argue that processes external to the flood policy subsystem (e.g., process of democratization and Hungary's accession to the European Union), along with the occurrence of the extreme flood events, enabled a coalition of individuals and organizations to press for policy change.  相似文献   

16.
The paper presents the results of an investigation of the height variations of dynamic processes in the 80–110 km height region, carried out in Kazan, U.S.S.R. (56°N, 49°E) by the radiometeor method during the MAC/EPSILON campaign. Experimental results show that the largest values of vertical wind gradients, as well as zonal and meridional temperature gradients can be found at heights of ~ 83 km. At heights of 80 ⩽ h ⩽ 100 km, we can observe energy absorption of IGW and tides which are the major sources of turbulent energy in the above-mentioned height interval. Using the effects of IGW energy absorption, values of the turbulent eddy diffusion coefficient Kl ranging from 1600 to 4400 m2/s were calculated for October 1987. The energy dissipation rate ϵ was estimated to be from 0.1 to 0.4 W/kg.  相似文献   

17.
A theoretical study is presented bearing on the thermospheric circulation and composition at polar latitudes. The observed motions and density perturbations in N2, O and He have signatures which may be understood in terms of two different source mechanisms. We consider electric field momentum coupling and Joule heating as well as interactions between both processes. A spectral model in terms of vector spherical harmonics (with magnetic coordinates) is used, delineating the diurnal and mean (time independent) components. The important non-linearities are evaluated in configuration space. The electric field model of Volland and the global average density and temperature variations of Hedin (MSIS) are adopted as input. Our analysis leads to the following conclusions. (1) The vortex type double cell polar circulation (zonal wave number m = 1) is primarily driven by collisional momentum transfer from electric field induced ion convection. (2) Because of the thermospheric low pass filter, a large time independent component (zonal wave number m = 0) is produced by Joule heating; the heavier species (N2) being concentrated where the lighter ones (O, He) are depleted, and vice versa due to wind induced diffusion (3) The electric field driven vortex circulation redistributes the mass and energy in the time independent density and temperature variations (from Joule heating), producing primarily diurnal variations (m = 1) in the temperature and composition near the pole and at auroral latitudes, again the heavier and lighter species varying out of phase. The above results are in substantial agreement with observations. It is worth noting that momentum rectification associated with the diurnally varying electric field and conductivity induces a weak zonally symmetric (single cell) prograde polar vortex. However, this motion is partially compensated by a retrograde vortex from geostrophic balance due to Joule heating, which dominates near the pole. These motions are small compared with the diurnally varying component in the polar circulation.  相似文献   

18.
The magnetopause and adjacent boundary layers of the Earth's magnetosphere play important roles in transferring momentum and energy from the solar wind to the magnetosphere-ionosphere system. The details of the different boundary processes, their ionospheric signatures and relative importance are not well known at present. Particle precipitation, field-aligned current, auroral emission, ionospheric ion drift and ground magnetic perturbations are among the low-altitude parameters that show signatures of various plasma processes in the LLBL and the magnetopause current layer. Magnetic merging events, Kelvin-Helmholtz waves, and pressure pulses excited by the variable solar wind/magnetosheath plasma are examples of boundary phenomena that may be coupled to the ionosphere via field-aligned currents. In this paper, attention is focussed on a specific category of auroral activity occurring in the cusp/cleft region predominantly during the southward directed interplanetary magnetic field (IMF). Co-ordinated observations from the ground and satellites in polar orbit have been used to study the temporal/spatial development of the events in relation to the background patterns of particle precipitation and ionospheric convection as well as the field-aligned current and ion drift characteristics of the individual events. The auroral phenomenon is characterized by a sequence of elongated forms moving laterally into the polar cap. Spatial scales of major events repeating every 5–10 min are ∼200 km (N-S) times 300–1000 km (E-W). Smaller scale auroral structures with more irregular occurrence rates are observed at times. The preliminary evidence suggests that the motion pattern is regulated by the IMF orientation, that is, the direction of longitudinal motion along the polar cap boundary is determined by the IMF BY polarity. The examples reported here occurred within 1000–1400 MLT, near the zero point potential line separating the morning and post-noon convection cells. During nonzero IMF BY the auroral structures are associated with channels of enhanced zonal ionospheric ion flow and Birkeland current sheets of opposite polarity, imbedded within the larger scale IMF BY-related cusp-mantle current system. These characteristics are discussed in relation to model predictions of ionospheric signatures of magnetopause plasma transients, with particular emphasis placed on impulsive magnetic merging events.  相似文献   

19.
The thermal histories of archaeological cereal grains have been explored with electron spin resonance spectroscopy by a quantitative study of pyrolysis-induced radical carbon. Comparison with modern samples of heated cereal grain has shown that the g value of the radical carbon signal is characteristic of exposure to a previous maximum temperature, and studies of other signal parameters suggest that further information, such as the duration of previous heating, may be deduced from such studies. The proposed method offers the possibility of quantitatively rigorous measurement in archaeological studies of cultural and technological processes that previously relied upon subjective assessment.  相似文献   

20.
We investigate mountain gazelle (Gazella gazella) carcass processing to reconstruct resource intensification strategies during the Epipalaeolithic period of northern Israel. We adopt a multivariate taphonomic approach to identify the processes that most influenced bone survivorship in five gazelle assemblages. All of the assemblages are characterized by significant density-mediated biases, yet in situ attrition played a minimal role in assemblage formation. In contrast, the survivorship of hare (Lepus capensis) skeletons is not mediated by bone density indicating that different prey taxa experienced independent taphonomic histories. Both gazelle cortical and cancellous bone is highly fragmented and the degree of fragmentation and survivorship are strongly correlated with fat yields. Results of multiple tests point to intensive marrow and grease extraction as the primary determinant of gazelle bone survivorship. Although gazelle carcasses were intensively utilized throughout the Epipalaeolithic, the intensity of use is stable across the duration of the period.  相似文献   

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