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51.
Auckland's post-suburban landscape is associated with new mixed-use apartment developments. When located in former industrial sites, these emergent residential and retail spaces constitute new-build gentrification and carry the potential to rupture existing people/place dynamics. This article examines material and socio-cultural processes associated with the redevelopment of an industrial quarry in Three Kings, Auckland. It is argued that the redevelopment constitutes a physical refashioning of a former industrial space located within a traditional working-class community. The development involves a remaking of the material and socio-cultural fabric of the neighbourhood and aligns with new-build gentrification practices. 相似文献
52.
Crab larval dispersal and, thus, adult population size can be influenced by oceanographic conditions, especially in highly dynamic and variable environments such as high-latitude estuaries. This study's primary goal was to understand larval timing, abundance, and distribution in relation to oceanographic effects between the more estuarine inner and more oceanic outer part of the subarctic estuary of Kachemak Bay (south-central Alaska, USA). Temperature and salinity measurements and plankton tows were taken along the boundary between the two bay parts from 31 March to 28 October 2008 on spring and neap tides. Summer water flow and stratification in Kachemak Bay were chiefly buoyancy driven, and predominant flow patterns were not affected by the large tidal range in the region. Larvae of seven brachyuran species were found over the sampling period, with seasonally different peak abundances. Larval spatial distribution patterns, presence of most larval stages for each species, and their seasonal timing and persistence within the water column suggest that most species are locally transported within or close to Kachemak Bay. The larval assemblage was correlated with seasonal changes in water temperature, and peak abundances of some species coincided with spring tides and/or frontal systems between the in- and outflow regions of the bay. The strong influence of freshwater on the local circulation pattern in the summer indicates that larval transport will likely be strongly affected by future changes in glacial melt and precipitation. 相似文献
53.
Tara A. Kniskern Jonathan A. Warrick Katherine L. Farnsworth Robert A. Wheatcroft Miguel A. Goñi 《Continental Shelf Research》2011,31(7-8):789-805
The majority of water and sediment discharge from the small, mountainous watersheds of the US West Coast occurs during and immediately following winter storms. The physical conditions (waves, currents, and winds) within and acting upon the proximal coastal ocean during these winter storms strongly influence dispersal patterns. We examined this river–ocean temporal coherence for four coastal river–shelf systems of the US West Coast (Umpqua, Eel, Salinas, and Santa Clara) to evaluate whether specific ocean conditions occur during floods that may influence coastal dispersal of sediment. Eleven years of corresponding river discharge, wind, and wave data were obtained for each river–shelf system from USGS and NOAA historical records, and each record was evaluated for seasonal and event-based patterns. Because near-bed shear stresses due to waves influence sediment resuspension and transport, we used spectral wave data to compute and evaluate wave-generated bottom-orbital velocities. The highest values of wave energy and discharge for all four systems were consistently observed between October 15 and March 15, and there were strong latitudinal patterns observed in these data with lower discharge and wave energies in the southernmost systems. During floods we observed patterns of river–ocean coherence that differed from the overall seasonal patterns. For example, downwelling winds generally prevailed during floods in the northern two systems (Umpqua and Eel), whereas winds in the southern systems (Salinas and Santa Clara) were generally downwelling before peak discharge and upwelling after peak discharge. Winds not associated with floods were generally upwelling on all four river–shelf systems. Although there are seasonal variations in river–ocean coherence, waves generally led floods in the three northern systems, while they lagged floods in the Santa Clara. Combined, these observations suggest that there are consistent river–ocean coherence patterns along the US West Coast during winter storms and that these patterns vary substantially with latitude. These results should assist with future evaluations of flood plume formation and sediment fate along this coast. 相似文献
54.
Jai Vaze Paul Barnett Geoffrey Beale Warrick Dawes Ray Evans Narendra Kumar Tuteja Brian Murphy Guy Geeves Michelle Miller 《水文研究》2004,18(9):1613-1637
A comprehensive framework for the assessment of water and salt balance for large catchments affected by dryland salinity is applied to the Boorowa River catchment (1550 km2), located in south‐eastern Australia. The framework comprised two models, each focusing on a different aspect and operating on a different scale. A quasi‐physical semi‐distributed model CATSALT was used to estimate runoff and salt fluxes from different source areas within the catchment. The effects of land use, climate, topography, soils and geology are included. A groundwater model FLOWTUBE was used to estimate the long‐term effects of land‐use change on groundwater discharge. Unlike conventional salinity studies that focus on groundwater alone, this study makes use of a new approach to explore surface and groundwater interactions with salt stores and the stream. Land‐use change scenarios based on increased perennial pasture and tree‐cover content of the vegetation, aimed at high leakage and saline discharge areas, are investigated. Likely downstream impacts of the reduction in flow and salt export are estimated. The water balance model was able to simulate both the daily observed stream flow and salt load at the catchment outlet for high and low flow conditions satisfactorily. Mean leakage rate of about 23·2 mm year?1 under current land use for the Boorowa catchment was estimated. The corresponding mean runoff and salt export from the catchment were 89 382 ML year?1 and 38 938 t year?1, respectively. Investigation of various land‐use change scenarios indicates that changing annual pastures and cropping areas to perennial pastures is not likely to result in substantial improvement of water quality in the Boorowa River. A land‐use change of about 20% tree‐cover, specifically targeting high recharge and the saline discharge areas, would be needed to decrease stream salinity by 150 µS cm?1 from its current level. Stream salinity reductions of about 20 µS cm?1 in the main Lachlan River downstream of the confluence of the Boorowa River is predicted. The FLOWTUBE modelling within the Boorowa River catchment indicated that discharge areas under increased recharge conditions could re‐equilibrate in around 20 years for the catchment, and around 15 years for individual hillslopes. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
55.
Share G.H. Murphy R.J. Dennis B.R. Schwartz R.A. Tolbert A.K. Lin R.P. Smith D.M. 《Solar physics》2002,210(1-2):357-372
The RHESSI high-resolution spectrometer detected γ-ray lines and continuum emitted by the Earth's atmosphere during impact
of solar energetic particles in the south polar region from 16:00–17:00 UT on 21 April 2002. The particle intensity at the
time of the observation was a factor of 10–100 weaker than previous events when gamma-rays were detected by other instruments.
This is the first high-resolution observation of atmospheric gamma-ray lines produced by solar energetic particles. De-excitation
lines were resolved that, in part, come from 14N at 728, 1635, 2313, 3890, and 5106 keV, and the 12C spallation product at ∼ 4439 keV. Other unresolved lines were also detected. We provide best-fit line energies and widths
and compare these with moderate resolution measurements by SMM of lines from an SEP event and with high-resolution measurements
made by HEAO 3 of lines excited by cosmic rays. We use line ratios to estimate the spectrum of solar energetic particles that
impacted the atmosphere. The 21 April spectrum was significantly harder than that measured by SMM during the 20 October 1989
shock event; it is comparable to that measured by Yohkoh on 15 July 2000. This is consistent with measurements of 10–50 MeV protons made in space at the time of the γ-ray observations. 相似文献
56.
M.T. Murphy J.K. Webb V.V. Flambaum J.X. Prochaska A.M. Wolfe 《Monthly notices of the Royal Astronomical Society》2001,327(4):1237-1243
Comparison of quasar (QSO) absorption-line spectra with laboratory spectra provides a precise probe for variability of the fine-structure constant, α , over cosmological time-scales. We constrain variation in α in 21 Keck/HIRES Si iv absorption systems using the alkali-doublet (AD) method in which changes in α are related to changes in the doublet spacing. The precision obtained with the AD method has been increased by a factor of 3: . We also analyse potential systematic errors in this result. Finally, we compare the AD method with the many-multiplet method, which has achieved an order of magnitude greater precision, and we discuss the future of the AD method. 相似文献
57.
58.
L. Kaderhandt A. Barr Domínguez R. Chini M. Hackstein M. Haas F. Pozo Nuez M. Murphy 《Astronomische Nachrichten》2015,336(7):677-681
We present a first overview of variable stars in the Bochum Galactic Disk Survey (GDS) with emphasis on eclipsing binaries (EBs). This ongoing survey is performed by a robotic twin refractor at the Universitätssternwarte Bochum located near Cerro Armazones in Chile. It comprises a mosaic of 268 fields in a stripe of Δb = ±3° along the Galactic plane observed once per month simultaneously in the Sloan r and i filters with a detection limit of rs ∼ 16 mag and is ∼ 15 mag. The data from the first three years until the end of February 2014 yields a total of 41718 variable stars with variability amplitudes between 0.1–6 mag. A cross‐match with SIMBAD identified 11 465 of these variables unambiguously, while 2184 had multiple matches; most of the remaining stars could be matched with 2MASS objects. Among the SIMBAD‐listed objects with single matches, only 1982 turned out as known variables while a further 256 are suspected of variability. That leaves a total of 39480 potentially new variables. The group of known variables comprises 419 stars (21 %) that are classified as EBs while 443 (22%) are of other types; for the remaining 1120 catalogued variables (57 %) the type is unknown. Investigating variability as a function of spectral type, we find that SIMBAD provides spectral types for 2811 (25 %) of the identified stars. Spectral classes B (26 %), A (20 %), and M (25%) contain the most numerous variables, while all other classes contribute less than 10% each. More than half of the B (55 %) and A (56%) stars are designated as EBs, suggesting that hundreds of new B‐ and A‐type EBs may be contained in the GDS archive. In contrast, among the numerous M stars no EBs are known. (© 2015 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
59.
C. R. Purcell R. Balasubramanyam M. G. Burton A. J. Walsh V. Minier M. R. Hunt-Cunningham L. L. Kedziora-Chudczer S. N. Longmore T. Hill I. Bains P. J. Barnes A. L. Busfield P. Calisse N. H. M. Crighton S. J. Curran T. M. Davis J. T. Dempsey G. Derragopian B. Fulton M. G. Hidas M. G. Hoare J.-K. Lee E. F. Ladd S. L. Lumsden T. J. T. Moore M. T. Murphy R. D. Oudmaijer M. B. Pracy J. Rathborne S. Robertson A. S. B. Schultz J. Shobbrook P. A. Sparks J. Storey T. Travouillion 《Monthly notices of the Royal Astronomical Society》2006,367(2):553-576
60.