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101.
Access to safe and adequate water and to sanitation has been a global developmental priority due to their intrinsic impacts on the achievement of the sustainable development goals. Despite the implementation of several measures to improve access to safe water and sanitation, urban dwellers in Ghana struggle to acquire water and access sanitation facilities. This paper identified and examined the vulnerable conditions of households to environmental inadequacies of potable water and sanitation and measures aimed at reducing the risks associated with them in the Ashaiman Municipality. The study revealed that, access to adequate water supply was not necessarily dependent on the physical location of house units, but on factors such as lack of building permit, financial constraints, rental conditions, administrative procedures and ill-suited housing arrangement. Inadequate solid and liquid waste management practices and poor drainage systems were major problems identified in the Municipality. The paper argues that water, drainage systems and logistics for waste management in deprived communities must be provided by the local government and service providers through public–private partnership agreements. We conclude that, planning rules, regulations and procedures should be strictly adhered to and vigorously enforced by the Municipality in order to have a well-organized and planned urban environment. 相似文献
102.
Austin Zwick 《GeoJournal》2018,83(4):679-691
The competitive pressures of neoliberal economies have compelled employers to devolve responsibilities to contractors and subcontractors. The rise information technology platforms have significantly accelerated this trend over past decade. “Sharing economy” companies have such widespread adoption of neoliberalism’s industrial relations that a new moniker—“the Gig Economy”—has taken root. Although shareholders and consumers have benefited, middle-class jobs have been squeezed in the process. This paper uses Uber as a case study to discuss how Sharing Economy entities are merely the latest iteration of companies to enact the neoliberal playbook, including (a) (mis)classifying workers, (b) engaging in regime shopping, and (c) employing the most economically vulnerable, rather than giving rise to a new world of work altogether. The result is a crowding out of middle-class employment by precarious ‘gigs’ that lack legal protections and benefits. 相似文献
103.
Characterisation and Simulation of the Multiscaling Properties of the Energy-Containing Scales of Horizontal Surface-Layer Winds 总被引:1,自引:1,他引:0
Michael K. Lauren Merab Menabde Alan W. Seed Geoffrey L. Austin 《Boundary-Layer Meteorology》1999,90(1):21-46
The multiscaling statistics of atmospheric surface-layer winds at low wavenumbers above farmland and in the lee of a mountain range were examined using a hot-wire and lightweight cup anemometer. It was found that the horizontal velocity spectra could be broken into high and low-wavenumber regimes according to the parameters given by this analysis. The low-wavenumber end of the spectrum possessed a spectral slope parameter that varied between values of 0.8 and 1.35 at the farmland site during the period of the experiment, and the high-wavenumber end – corresponding to the inertial range – possessed a spectral slope slightly greater than -5/3. The larger values for this parameter for the low-wavenumber end appeared to coincide with unstable conditions. In the lee of the mountain range, the low-wavenumber spectral slope parameter was larger still, at 1.45. The low-wavenumber signals over farmland were much less intermittent than inertial-range signals, but in the lee of the mountain range the intermittency increased. From this analysis, it was shown that the statistical properties of the recorded wind signal could be reproduced using a bounded random multiplicative cascade. The model was successfully used to simulate the wind velocity field directly, rather than simulating the energy dissipation field. Since the spectral slope parameter for low wavenumbers appeared to be a function of atmospheric stability, the method presented is a simple way of generating wind signals characteristic of a variety of atmospheric conditions. 相似文献
104.
Sulfate (S and O) isotopes used in conjunction with sulfate concentration provide a tracer for ground water contributions to base flow. They are particularly useful in areas where rock sources of contrasting S isotope character are juxtaposed, where water chemistry or H and O isotopes fail to distinguish water sources, and in arid areas where rain water contributions to base flow are minimal. Sonoita Creek basin in southern Arizona, where evaporite and igneous sources of sulfur are commonly juxtaposed, serves as an example. Base flow in Sonoita Creek is a mixture of three ground water sources: A, basin ground water with sulfate resembling that from Permian evaporite; B, ground water from the Patagonia Mountains; and C, ground water associated with Temporal Gulch. B and C contain sulfate like that of acid rock drainage in the region but differ in sulfate content. Source A contributes 50% to 70%, with the remainder equally divided between B and C during the base flow seasons. The proportion of B generally increases downstream. The proportion of A is greatest under drought conditions. 相似文献
105.
Glibert PM Azanza R Burford M Furuya K Abal E Al-Azri A Al-Yamani F Andersen P Anderson DM Beardall J Berg GM Brand L Bronk D Brookes J Burkholder JM Cembella A Cochlan WP Collier JL Collos Y Diaz R Doblin M Drennen T Dyhrman S Fukuyo Y Furnas M Galloway J Granéli E Ha DV Hallegraeff G Harrison J Harrison PJ Heil CA Heimann K Howarth R Jauzein C Kana AA Kana TM Kim H Kudela R Legrand C Mallin M Mulholland M Murray S O'Neil J Pitcher G Qi Y Rabalais N Raine R Seitzinger S Salomon PS Solomon C 《Marine pollution bulletin》2008,56(6):1049-1056
The proposed plan for enrichment of the Sulu Sea, Philippines, a region of rich marine biodiversity, with thousands of tonnes of urea in order to stimulate algal blooms and sequester carbon is flawed for multiple reasons. Urea is preferentially used as a nitrogen source by some cyanobacteria and dinoflagellates, many of which are neutrally or positively buoyant. Biological pumps to the deep sea are classically leaky, and the inefficient burial of new biomass makes the estimation of a net loss of carbon from the atmosphere questionable at best. The potential for growth of toxic dinoflagellates is also high, as many grow well on urea and some even increase their toxicity when grown on urea. Many toxic dinoflagellates form cysts which can settle to the sediment and germinate in subsequent years, forming new blooms even without further fertilization. If large-scale blooms do occur, it is likely that they will contribute to hypoxia in the bottom waters upon decomposition. Lastly, urea production requires fossil fuel usage, further limiting the potential for net carbon sequestration. The environmental and economic impacts are potentially great and need to be rigorously assessed. 相似文献
106.
Mesoscale aspects of the Urban Heat Island around New York City 总被引:15,自引:1,他引:15
S. D. Gedzelman S. Austin R. Cermak N. Stefano S. Partridge S. Quesenberry D. A. Robinson 《Theoretical and Applied Climatology》2003,75(1-2):29-42
Summary ?A mesoscale analysis of the Urban Heat Island (UHI) of New York City (NYC) is performed using a mesoscale network of weather
stations. In all seasons the UHI switches on rapidly in late afternoon and shuts down even more rapidly shortly after dawn.
It averages about 4 °C in summer and autumn and 3 °C in winter and spring. It is largest on nights with clear skies, low relative
humidity through much of the troposphere, and weak northwest winds, when it may exceed 8 °C. The synoptic meteorological situation
associated with the largest UHI occurs roughly two to three nights after cold front passages.
During spring and summer, sea breezes commonly reduce and delay the UHI and displace it about 10 km to the west. Backdoor
cold fronts, which occur most frequently in spring and early summer, reduce or even reverse the UHI, as cold air from the
water to the northeast keeps NYC colder than the western suburbs. Cases documenting the sensitivity and rapidity of changes
of the UHI to changes in parameters such as cloud cover, ceiling, and wind speed and direction are presented.
Received August 16, 2001; revised October 6, 2002; accepted November 20, 2002
Published online March 17, 2003 相似文献
107.
Seismic mapping of high-resolution multichannel seismic profiles along the New Jersey margin illustrates how characteristics of middle–late Miocene clinoformal sequence boundaries (SBs) change markedly along strike in presumed response to local depositional and erosional processes. Most SBs converge from SW to NE, in part as a result of the influence of underlying basin morphology on accommodation space, but also in response to differential subsidence and presumed along-strike variations in sediment supply from the adjacent margin. The curvature of clinoform breaks, historically viewed as marking palaeo-shelf edges, is variable and such breaks are rarely sharp. Gently curved palaeo-shelf/slope transitions cannot be assigned precise palaeobathymetric significance and probably instead reflect post-depositional sediment reworking. The amount of erosional truncation landward of clinoform breaks varies significantly. Documented along-strike variability in SB morphology occurs, even though middle–late Miocene palaeo-shelf edges are nearly linear in plan view. Therefore, such linearity cannot be a product of uniform sedimentary processes and/or accumulation along strike, but instead reflects elongation of depocentres of originally variable cross-sectional geometry, possibly with the assistance of along-strike currents. The observed lateral geometric heterogeneity of Neogene sequences can exert profound and unwanted influences on the outcome of scientific drilling intended to calibrate seismic stratigraphic interpretations in the absence of sufficient three-dimensional (3D) seismic control. 相似文献
108.
Martin Austin Tim Scott Jeff Brown Jenna Brown Jamie MacMahan Gerd Masselink Paul Russell 《Continental Shelf Research》2010
A field experiment was conducted on a high energy macro-tidal beach (Perranporth, UK) to examine rip current dynamics over a low-tide transverse bar/rip system in response to changing tide and wave conditions. Hydrodynamic data were collected using an array of in situ acoustic doppler current meters and pressure transducers, as well as 12 GPS-tracked Lagrangian surf zone drifters. Inter-tidal and sub-tidal morphology were measured through RTK-GPS and echo-sounder surveys. Data were collected for eight consecutive days (15 tides) over a spring-neap tidal cycle with tidal ranges of 4–6.5 m and offshore significant wave heights of 1–2 m and peak periods of 5–12 s. 相似文献
109.
Characterizing hydrological processes in a semiarid rangeland watershed: A hydrogeophysical approach
Austin M. Carey Ginger B. Paige Bradley J. Carr W. Steven Holbrook Scott N. Miller 《水文研究》2019,33(5):759-774
The complex ecohydrological processes of rangelands can be studied through the framework of ecological sites (ESs) or hillslope‐scale soil–vegetation complexes. High‐quality hydrologic field investigations are needed to quantitatively link ES characteristics to hydrologic function. Geophysical tools are useful in this context because they provide valuable information about the subsurface at appropriate spatial scales. We conducted 20 field experiments in which we deployed time‐lapse electrical resistivity tomography (ERT), variable intensity rainfall simulation, ground‐penetrating radar (GPR), and seismic refraction, on hillslope plots at five different ESs within the Upper Crow Creek Watershed in south‐east Wyoming. Surface runoff was measured using a precalibrated flume. Infiltration data from the rainfall simulations, coupled with site‐specific resistivity–water content relationships and ERT datasets, were used to spatially and temporally track the progression of the wetting front. First‐order constraints on subsurface structure were made at each ES using the geophysical methods. Sites ranged from infiltrating 100% of applied rainfall to infiltrating less than 60%. Analysis of covariance results indicated significant differences in the rate of wetting front progression, ranging from 0.346 m min?1/2 for sites with a subsurface dominated by saprolitic material to 0.156 m min?1/2 for sites with a well‐developed soil profile. There was broad agreement in subsurface structure between the geophysical methods with GPR typically providing the most detail. Joint interpretation of the geophysics showed that subsurface features such as soil layer thickness and the location of subsurface obstructions such as granite corestones and material boundaries had a large effect on the rate of infiltration and subsurface flow processes. These features identified through the geophysics varied significantly by ES. By linking surface hydrologic information from the rainfall simulations with subsurface information provided by the geophysics, we can characterize the ES‐specific hydrologic response. Both surface and subsurface flow processes differed among sites and are directly linked to measured characteristics. 相似文献
110.
Seaports are located in vulnerable areas to climate change impacts: on coasts susceptible to sea-level rise and storms or at mouths of rivers susceptible to flooding. They serve a vital function within the local, regional, and global economy. Their locations in the heart of sensitive estuarine environments make it an imperative to minimize the impacts of natural hazards. Climate impacts, like a projected SLR of .6?m to 2?m and doubling of Category 4 and 5 hurricanes by 2100, will result in more extreme events at many seaports. To assess the current state of knowledge on this issue, we surveyed port authorities from around the world about how administrators felt climate change might impact their operations, what sea-level change would create operational problems, and how they planned to adapt to new environmental conditions. The planned rapid expansion of ports reported by the survey respondents indicates that adaptation measures should be considered as ports construct new infrastructure that may still be in use at the end of the century. Respondents agreed that the ports community needs to address this issue and most felt relatively uninformed about potential climate impacts. Although most ports felt that SLR would not be an issue at their port this century, sea-level rise was nevertheless an issue of great concern. Our results suggest opportunities for the scientific community to engage with port practitioners to prepare proactively for climate change impacts on this sector. 相似文献