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131.
Climate change disproportionately impacts the world’s poorest countries. A recent World Bank report highlighted that over 100 million people are at risk of falling into extreme poverty as a result of climate change. There is currently a lack of information about how to simultaneously address climate change and poverty. Climate change challenges provide an opportunity for those impacted most to come up with new and innovative technologies and solutions. This article uses an example from Mozambique where local and international partners are working side-by-side, to show how developing countries can simultaneously address climate change and poverty reduction using an ecosystem-based adaptation approach. Using ecosystem-based adaptation, a technique that uses the natural environment to help societies adapt to climate change, developing countries can lead the way to improve climate adaptation globally. This paradigm shift would help developing countries become leaders in ecosystem-based adaptation and green infrastructure techniques and has implications for climate policy worldwide.

POLICY RELEVANCE

The Paris Agreement resulting from the United Nations Framework Convention on Climate Change (UNFCCC) 21st Conference of Parties (COP 21) in December 2015 was rightly lauded for its global commitment to cut greenhouse gas emissions. However, COP 21 was also historic because of its call for non-party stakeholders to address climate change, inclusion of a global goal of ‘enhancing adaptive capacity, strengthening resilience and reducing vulnerability’, and the United States’ commitment of $800 million to adaptation funding. The combination of recognizing the need for new stakeholders to commit to climate change adaptation, the large impact climate change will have on the developing world, and providing access to funds for climate change adaptation creates a unique opportunity for developing countries to pave the way in adaptation policies in practices. Currently, developing countries are creating National Adaptation Plans (NAPs) for the UNFCCC. Through including a strong component of ecosystem-based adaptation in NAPs, developing countries can shape their countries’ policies, improve local institutions and governments, and facilitate a new generation of innovative leaders. Lessons learned in places like Mozambique can help lead the way in other regions facing similar climatic risks.  相似文献   

132.
Colin G Pooley  Jean Turnbull 《Area》1999,31(3):281-292
Summary The paper uses original quantitative and qualitative evidence to examine changes in the distance travelled and time spent on the journey to work in twentieth-century Britain. Emphasis is placed on variations by gender and location, and on the implications of modal change. We suggest that analysis of past commuting trends may have implications for contemporary transport policy.  相似文献   
133.
A horizontal shear flow having a Rossby number, Ro, greater than unity on a rotating plane can become unstable when its shear value is less than −f, the Coriolis frequency. In this paper, this instability is investigated for an O(10 km) submesoscale, sinusoidal shear flow in a thin homogeneous fluid layer as in an oceanic mixed layer or a shallow sea. The most unstable mode is shown by a linear analysis to occur in a narrow localized region centered around the maximum anticyclonic current shear. However, nonlinear numerical calculations show that the instability can grow to encompass both unstable and stable regions of the current. A consequence of this finite-amplitude evolution is the formation of surface convergence/shear fronts. The possibility that inertial instability mechanism is a source of some surface convergence/shear features seen in remote sensing images of the sea surface is discussed. A comparison is made with the shear-flow instability that can occur concurrently in a sinusoidal shear current, and inertial instability is shown to be the dominant instability mechanism in the immediate range above Ro=2.  相似文献   
134.
Phase equilibria in the ternary system H2O-CO2-NaCl were studied at 800 °C and 9 kbar in internally heated gas pressure vessels using a modified synthetic fluid inclusion technique. The low rate of quartz overgrowth along the `b' and `a' axes of quartz crystals was used to avoid fluid inclusion formation during heating, prior to attainment of equilibrium run conditions. The density of CO2 in the synthetic fluid inclusions was calibrated using inclusions in the binary H2O-CO2 system synthesised by the same method and measured on the same heating-freezing stage. In the two-phase field, two types of fluid inclusions with different densities of CO2 were observed. Using mass balance calculations, these inclusions are used to constrain the miscibility gap and the orientation of two-phase tie-lines in the H2O-CO2-NaCl system at 800 °C and 9 kbar. The equation of state of Duan et al. (1995) approximately describes the P-T section of the ternary system up to about 40 wt% of NaCl. At higher NaCl concentrations the measured solubility of CO2 in the brine is much smaller than predicted by the EOS. A “salting out” effect must be added to the equation of state to include coulomb interaction in the model of Anderko and Pitzer (1993) and Pitzer and Jiang (1996). The new experimental data together with published data up to 5 kbar (Shmulovich et al. 1995) encompass practically all subsolidus crustal P-T conditions. A feature of the new experimental results is the large compositional range in the H2O-CO2-NaCl system occupied by the stability fields of halite + CO2-rich fluid ± H2O-NaCl brine. The prediction of halite stability in equilibrium with CO2-rich fluid in deep-crustal rocks is supported by recent petrological and fluid inclusion studies of granulites. Received: 29 June 1998 / Accepted: 17 March 1999  相似文献   
135.
The primary oils obtained in high yields from fast (fluidised-bed) pyrolysis of biomass generally have high oxygen contents (ca. 40% w/w). The scope for using pyrolysis under hydrogen pressure (hydropyrolysis), to give oils with much lower oxygen contents compared to normal pyrolysis has been investigated. Fixed-bed hydropyrolysis tests have been conducted on cellulose, sugar cane bagasse and eucalyptus wood using hydrogen pressures up to 10 MPa, with heating rates of 5 and 300°C min−1. A colloidal FeS catalyst was used in some tests (Fe loading of 5%, w/w) to increase overall conversions. Further, the attractive option of using a two-stage reactor in which the primary oil vapors are passed though a bed of hydrotreating catalyst is also described. Raising the hydrogen pressure from atmospheric to 10 MPa reduced the oxygen content of the primary oil by over 10% to below 20% w/w. The addition of a dispersed iron sulphide catalyst gave conversions close to 100% for all three biomass samples investigated at 10 MPa under conditions in the fixed-bed reactor where significant diffusional resistances existed and reduced the oxygen content of the bio-oil by a further 10%. Although NMR indicated that the oils became increasingly aromatic as more oxygen was removed, the increase in hydrogen pressure decreased the extent of overall aromatisation that occurs primarily due to the lower char yields obtained. In two-stage tests for cellulose, using a commercial sulphided Ni/Mo γ-Al2O3 catalyst at 400°C, increasing the hydrogen pressure from 2.5 to 10 MPa decreased the oxygen content of the oil by over 20% to 10% w/w. The H/C ratios were higher and O/C ratios smaller for the two-stage bio-oils compared to their single stage counterparts. However, the differences in the O/C ratios between the single and two-stage bio-oils increase with pressure.  相似文献   
136.
137.
In meandering rivers cut into bedrock, erosion across a channel cross‐section can be strongly asymmetric. At a meander apex, deep undercutting of the outer bank can result in the formation of a hanging cliff (which may drive hillslope failure), whereas the inner bank adjoins a slip‐off slope that connects to the hillslope itself. Here we propose a physically‐based model for predicting channel planform migration and incision, point bar and slip‐off slope formation, bedrock abrasion, the spatial distribution of alluvial cover, and adaptation of channel width in a mixed bedrock‐alluvial channel. We simplify the analysis by considering a numerical model of steady, uniform bend flow satisfying cyclic boundary conditions. Thus in our analysis, ‘sediment supply’, i.e. the total volume of alluvium in the system, is conserved. In our numerical simulations, the migration rate of the outer bank is a specified parameter. Our simulations demonstrate the existence of an approximate state of dynamic equilibrium corresponding to a near‐solution of permanent form in which a bend of constant curvature, width, cross‐sectional shape and alluvial cover distribution migrates diagonally downward at constant speed, leaving a bedrock equivalent of a point bar on the inside of the bend. Channel width is set internally by the processes of migration and incision. We find that equilibrium width increases with increasing sediment supply, but is insensitive to outer bank migration rate. The slope of the bedrock point bar varies inversely with both outer bank migration rate and sediment supply. Although the migration rate of the outer bank is externally imposed here, we discuss a model modification that would allow lateral side‐wall abrasion to be treated in a manner similar to the process of bedrock incision. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
138.
Enhanced production of unconventional hydrocarbons in the United States has driven interest in natural gas development globally, but simultaneously raised concerns regarding water quantity and quality impacts associated with hydrocarbon extraction. We conducted a pre‐development assessment of groundwater geochemistry in the critically water‐restricted Karoo Basin, South Africa. Twenty‐two springs and groundwater samples were analyzed for major dissolved ions, trace elements, water stable isotopes, strontium and boron isotopes, hydrocarbons and helium composition. The data revealed three end‐members: a deep, saline groundwater with a sodium‐chloride composition, an old, deep freshwater with a sodium‐bicarbonate‐chloride composition and a shallow, calcium‐bicarbonate freshwater. In a few cases, we identified direct mixing of the deep saline water and shallow groundwater. Stable water isotopes indicate that the shallow groundwater was controlled by evaporation in arid conditions, while the saline waters were diluted by apparently fossil meteoric water originated under wetter climatic conditions. These geochemical and isotopic data, in combination with elevated helium levels, suggest that exogenous fluids are the source of the saline groundwater and originated from remnant seawater prior to dilution by old meteoric water combined with further modification by water‐rock interactions. Samples with elevated methane concentrations (>14 ccSTP/kg) were strongly associated with the sodium‐chloride water located near dolerite intrusions, which likely provide a preferential pathway for vertical migration of deeply sourced hydrocarbon‐rich saline waters to the surface. This pre‐drill evaluation indicates that the natural migration of methane‐ and salt‐rich waters provides a source of geogenic contamination to shallow aquifers prior to shale gas development in the Karoo Basin.  相似文献   
139.
140.
High-level weathering limits separating ice-scoured topography from frost-weathered detritus were identified on 28 mountains in Wester Ross at altitudes of 700–960 m, and a further 22 peaks support evidence of ice scouring to summit level. Weathering limits are defined most clearly on sandstone and gneiss, which have resisted frost shattering during the Late Devensian Lateglacial, but can also be distinguished on schists and quartzite. Schmidt hammer measurements and analyses of clay mineral assemblages indicate significantly more advanced rock and soil weathering above the weathering limits. The persistence of gibbsite above weathering limits indicates that they represent the upper limit of Late Devensian glacial erosion. The regular decline of weathering-limit altitudes along former flowlines eliminates the possibility that the weathering limits represent former thermal boundaries between protective cold-based and erosive warm-based ice. The weathering limits are therefore interpreted as periglacial trimlines that define the maximum surface altitude of the last ice sheet. Calculated basal shear stresses of 50–95 kPa are consistent with this interpretation. Reconstruction of ice-sheet configuration indicates that the former ice-shed lay above 900 m along the present watershed, and that the ice surface descended northwestwards, with broad depressions along major troughs and localised domes around independent centres of ice dispersal. Extrapolation of the ice surface gradient and altitude suggests that the ice sheet did not overrun the Outer Hebrides, but was confluent with the independent Outer Hebrides ice-cap in the North Minch basin. Erratics located up to 140 m above the reconstructed ice surface are inferred to have been emplaced by a pre-Late Devensian ice sheet (or ice sheets) of unknown age. © 1997 John Wiley & Sons, Ltd.  相似文献   
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