Cities versus agriculture: revisiting intersectoral water transfers, potential gains and conflicts

Water scarcity / Water demand / Water transfer / Water use / Water supply / Water allocation / Environmental effects / Water market

Cities versus agriculture : revisiting intersectoral water transfers, potential gains and conflicts

The report is anchored in an annex that examines how cities round the world have in practice acquired water. While direct conflicts between urban and rural interests characterize some of the case studies presented (Ta'iz in Yemen being an extreme example), the empirical evidence suggests that, by-and-large, cities have been able to obtain supplies, often at greater cost than is necessary but without significantly compromising their ability to expand and prosper, even in most inauspicious locations. Where citizens face shortages or any other water problem, the report argues that this is predominantly due to development and financing constraints rather than to water shortages as such. Under conditions of scarcity, any transfers to cities will probably have some adverse impact on agriculture. However, the volume transferred is typically small and, though important social and equity issues arise, it is argued that farmers can often adjust. And where the environment is adversely affected by human impacts, this is predominantly an issue between the environment and agriculture and not between the environment and cities, at least in regard to water quantity. The section titled "Urban Water Scarcity and Its Links to Irrigation" sets the scene by reviewing what is meant by urban water scarcity and its links to irrigation, investigating its physical, political and economic dimensions. The section titled "Intersectoral Transfers" categorizes different types of transfers and transfer mechanisms. In the light of this typology, the section titled "Intersectoral Water Transfers in Practice" discusses how transfers are effected in practice with reference to the empirical evidence in the annex. The section titled "Are Urban Uses Constrained by Agriculture?" seeks to answer the question: are urban uses in practice constrained by agriculture. And, finally, the section titled "Where Are We Heading?" discusses some ways ahead and the conclusion summarizes the report's main findings

Cities vs. agriculture : a review of intersectoral water re-allocation

Water demand management, or making better use of the water we have - as opposed to augmenting supply - is increasingly proposed as a way of mitigating water-scarcity problems. Moving water away from agriculture to uses with higher economic value is one of the main measures widely seen as desirable. Sectoral "allocation stress" is seen as resulting from the disproportionate share, and inefficient use of water in the agricultural sector. This apparent misallocation is often attributed to the failure of government to allocate water rationally. This paper revisits this commonly-accepted wisdom and examines the nature of urban water scarcity, showing the importance of economic and political factors, shaped by incentives to decision-makers, and sometimes compounded by climatic conditions. It shows that cities' growth is not generally constrained by competition with agriculture. In general, rather than using a narrow financial criterion, cities select options that go along the "path of least resistance," whereby economic, social and political costs are considered in conjunction. The question of allocation stress is thus reframed into an inquiry of how transfers effectively occur and can be made more effective

Clinical utility of ultrasound guidance for intra-articular knee injections: a review

Intra-articular corticosteroid and hyaluronic acid injections provide short-term symptom amelioration for arthritic conditions involving structural damage or degenerative changes in the knee. Conventional palpation-guided anatomical injections frequently result in inaccurate needle placement into extra-articular tissue and adjacent structures. The purpose of this review was to determine the effect of ultrasound guidance on the accuracy of needle placement, clinical outcomes, and cost-effectiveness in comparison with anatomical landmark-guided intra-articular large joint injections, with particular emphasis on the knee. A total of 13 relevant studies were identified; five studied the knee, seven studied the shoulder, one used both the knee and shoulder, and none studied the hip. Ultrasound was used in seven studies; the remaining studies utilized air arthrography, fluoroscopy, magnetic resonance arthrography, or magnetic resonance imaging. Across all studies (using all imaging modalities and all joints), needle placement accuracy ranged from 63% to 100% with ultrasound and from 39% to 100% with conventional anatomical guidance. Imaging guidance improved the accuracy of intra-articular injections of the knee (96.7% versus 81.0%, P < 0.001) and shoulder (97.3% versus 65.4%, P < 0.001). In particular, ultrasound guidance of knee injections resulted in better accuracy than anatomical guidance (95.8% versus 77.8%, P < 0.001), yielding an odds ratio of 6.4 (95% confidence interval 2.9–14). Ultrasound guidance notably improves injection accuracy in the target intra-articular joint space of large joints including the knee. The enhanced injection accuracy achieved with ultrasound needle guidance directly improves patient-reported clinical outcomes and cost-effectiveness

The propensity to cycle tool: An open source online system for sustainable transport planning

© 2016 Robin Lovelace, Anna Goodman, Rachel Aldred, Nikolai Berkoff, Ali Abbas, and James Woodcock.Getting people cycling is an increasingly common objective in transport planning institutions worldwide. A growing evidence base indicates that high quality infrastructure can boost local cycling rates. Yet for infrastructure and other cycling measures to be effective, it is important to intervene in the right places, such as along ‘desire lines’ of high latent demand. This creates the need for tools and methods to help answer the question ‘where to build?’. Following a brief review of the policy and research context related to this question, this paper describes the design, features and potential applications of such a tool. The Propensity to Cycle Tool (PCT) is an online, interactive planning support system that was initially developed to explore and map cycling potential across England (see www.pct.bike). Based on origin-destination data it models cycling levels at area, desire line, route and route network levels, for current levels of cycling, and for scenario-based ‘cycling futures.’ Four scenarios are presented, including ‘Go Dutch’ and ‘Ebikes,’ which explore what would happen if English people had the same propensity to cycle as Dutch people and the potential impact of electric cycles on cycling uptake. The cost effectiveness of investment depends not only on the number of additional trips cycled, but on wider impacts such as health and carbon benefits. The PCT reports these at area, desire line, and route level for each scenario. The PCT is open source, facilitating the creation of scenarios and deployment in new contexts. We conclude that the PCT illustrates the potential of online tools to inform transport decisions and raises the wider issue of how models should be used in transport planning.The work presented was funded by the Department for Transport (contract no. RM5019SO7766: “Provision of Research Programme into Cycling: Propensity to Cycle”), with contract facilitation and project management by Brook Lyndhurst in Phase 1, and by Atkins in Phase 2. RL’s contribution was supported by the Consumer Data Research Centre (ESRC grant number ES/L011891/1). JW’s contribution was supported by an MRC Population Health Scientist Fellowship. JW’s and AA’s contributions were supported by the Centre for Diet and Activity Research (CEDAR), a UKCRC Public Health Research Centre of Excellence funded by the British Heart Foundation, Cancer Research UK, Economic and Social Research Council, Medical Research Council, the National Institute for Health Research (NIHR), and the Wellcome Trust. AG’s contribution was supported by an NIHR post-doctoral fellowship. The views reported in this paper are those of the authors and do not necessarily represent those of the DfT, Brook Lyndhurst, Atkins the NIHR, the NHS or the Department for Health

Satellite to Ground-based LIDAR Comparisons using MPLNET Data Products

The Micro-Pulse Lidar Network (MPLNET) is a network of ground-based lidar systems that provide continuous long-term observations of aerosol and cloud properties at approximately 10 different locations around the globe. Each site in the network uses an elastic scattering lidar co-located with a sunphotometer to provide data products of aerosol optical physical properties. Data products from sites are available on a next-day basis from the MPLNET website. Expansion of the network is based on partnering with research groups interested in joining MPLNET. Results have contributed to a variety of studies including aerosol transport studies and satellite calibration and validation efforts. One of the key motivations for MPLNET is to contribute towards the calibration and validation of satellite-based lidars such as GLAS/ICESAT and CALIPSO. MPLNET is able to provide comparison to several of the key aerosol and cloud CALIPSO data products including: layer height and thickness, optical depth, backscatter and extinction profiles, and the extinction-to-backscatter ratio

Spatiotemporal Path-Matching for Comparisons Between Ground- Based and Satellite Lidar Measurements

The spatiotemporal sampling differences between ground-based and satellite lidar data can contribute to significant errors for direct measurement comparisons. Improvement in sample correspondence is examined by the use of radiosonde wind velocity to vary the time average in ground-based lidar data to spatially match coincident satellite lidar measurements. Results are shown for the 26 February 2004 GLAS/ICESat overflight of a ground-based lidar stationed at NASA GSFC. Statistical analysis indicates that improvement in signal correlation is expected under certain conditions, even when a ground-based observation is mismatched in directional orientation to the satellite track

Scenarios of cycling to school in England, and associated health and carbon impacts: Application of the ‘Propensity to Cycle Tool’

© 2019 The Authors Background: The Propensity to Cycle Tool (PCT) is a freely available, interactive tool help prioritise cycling initially launched in England in 2017 and based on adult commuting data. This paper applies the method to travel to school data, and assesses health and carbon benefits based on nationwide scenarios of cycling uptake. Methods: The 2011 National School Census provides origin-destination data for all state-funded schools in England (N = 7,442,532 children aged 2–18 in 21,443 schools). Using this dataset, we modelled propensity to cycle as a function of route distance and hilliness between home and school. We generated scenarios, including ‘Go Dutch’ – in which English children were as likely to cycle as Dutch children, accounting for trip distance and hilliness. We estimated changes in the level of cycling, walking, and driving, and associated impacts on physical activity and carbon emissions. Results: In 2011, 1.8% of children cycled to school (1.0% in primary school, 2.7% in secondary school). If Dutch levels of cycling were reached, under the Go Dutch scenario, this would rise to 41.0%, a 22-fold increase. This is larger than the 6-fold increase in Go Dutch for adult commuting. This would increase total physical activity among pupils by 57%, and reduce transport-related carbon emissions by 81 kilotonnes/year. These impacts would be substantially larger in secondary schools than primary schools (a 96% vs. 9% increase in physical activity, respectively). Conclusion: Cycling to school is uncommon in England compared with other Northern European countries. Trip distances and hilliness alone cannot explain the difference, suggesting substantial unmet potential. We show that policies resulting in substantial uptake of cycling to school would have important health and environmental benefits. At the level of road networks, the results can inform local investment in safe routes to school to help realise these potential benefits.. JW and AA's contributions were supported by the Centre for Diet and ActivityResearch (CEDAR), a UKCRC Public Health Research Centre of Excellence funded by the British Heart Foundation, Cancer ResearchUK, Economic and Social Research Council, Medical Research Council, the National Institute for Health Research (NIHR), andthe Wellcome Trust