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An increasing number of different types of hydrological, land surface, and rainfall-runoff models exist to estimate streamflow in river networks. Results from various model runs from global to local scale are readily available online. However, the usability of these products is often limited, as they often come aggregated in spatial units which are not compatible with the desired analysis purpose. We present here an R package, a software library hydrostreamer v1.0 which aims to improve the usability of existing runoff products by addressing the Modifiable Area Unit Problem, and allows non-experts with little knowledge of hydrology-specific modelling issues and methods to use them for their analyses. Hydrostreamer workflow includes 1) interpolation from source zones to target zones, 2) river routing, and 3) data assimilation via model averaging, given multiple input runoff and observation data. The software implements advanced areal interpolation methods and area-to-line interpolation not available in other products, and is the first R package to provide vector-based routing. Hydrostreamer is kept as simple as possible – intuitive with minimal data requirements – and minimizes need for calibration. We tested the performance of hydrostreamer by downscaling freely available coarse-resolution global runoff products from the Inter-Sectoral Impact Model Intercomparison Project (ISIMIP) in an application in 3S Basin in Southeast Asia. Results are compared to observed discharges as well as two benchmark streamflow data products, finding comparable or improved performance. Hydrostreamer v1.0 is open source and is available from http://github.com/mkkallio/hydrostreamer/ under MIT licence. [ABSTRACT FROM AUTHOR]

Development of joint irrigation infrastructure increasingly depends on investment decisions made by individual farmers. Farmers base their decisions to invest on their current knowledge and understanding. As irrigation infrastructure development is ultimately a group decision, it is beneficial if individuals have a common understanding of the various values at stake. Sharing the personal reasoning behind individual decisions is a promising approach to build such common understanding. This study demonstrates application of participatory crossover analysis at a workshop in Tasmania, Australia. The workshop gave farmers the opportunity to discuss their broader considerations in investment decisions, beyond just financial or monetary factors. It centered on the question, “In what conditions would you—the individual farmer—invest?” The participants’ willingness to pay, in the form of crossover points, was presented as a set of scenarios to start an explorative discussion between irrigators and non-irrigators. Evaluation feedback indicates that the workshop enabled participants to share new information, improved understanding of differences between neighbors, and generated more respect for others and their decisions. As expected, reasoning went beyond economic concerns, and changed over time. Lifestyle choices, long-term intergenerational planning, perceived risks, and intrinsic motivations emerged as factors influencing water valuation. Simply having a facilitated discussion about the reasons underlying individuals’ willingness to pay seems to be a useful tool for better informed decision-making about joint irrigation infrastructure, and is worth testing in further case studies. [ABSTRACT FROM AUTHOR]

Climate oscillations are periodically fluctuating oceanic and atmospheric phenomena, which are related to variations in weather patterns and crop yields worldwide. In terms of crop production, the most widespread impacts have been observed for the El Niño Southern Oscillation (ENSO), which has been found to impact crop yields in all continents that produce crops, while two other climate oscillations – the Indian Ocean Dipole (IOD) and the North Atlantic Oscillation (NAO) – have been shown to impact crop production especially in Australia and Europe, respectively. In this study, we analyse the impacts of ENSO, IOD and NAO on the growing conditions of maize, rice, soybean and wheat at the global scale, by utilizing crop yield data from an ensemble of global gridded crop models simulated for a range of crop management scenarios. Our results show that simulated crop yield variability is correlated to climate oscillations to a wide extent (up to almost half of all maize and wheat harvested areas for ENSO) and in several important crop producing areas, e.g. in North America (ENSO, wheat), Australia (IOD & ENSO, wheat) and northern South America (ENSO, soybean). Further, our analyses show that higher sensitivity to these oscillations can be observed for rainfed, and fully fertilized scenarios, while the sensitivity tends to be lower if crops are fully irrigated. Since, the development of ENSO, IOD and NAO can be reliably forecasted in advance, a better understanding about the relationship between crop production and these climate oscillations can improve the resilience of the global food system to climate related shocks. [ABSTRACT FROM AUTHOR]

China’s rapid urbanization in areas prone to flood or drought events can be seen as a double-edged sword. Urbanization enlarges the population exposed to these hazards, but the resulting socio-economic development also helps build resilience. This article quantifies flood occurrence, drought severity, and related resilience in 81 cities in Mainland China. The extent of flood exposure was notable, both in absolute terms as well as in relation to the drought-prone urban population. China needs to integrate urban flood/drought policy making with sustainable urbanization policy making to best contribute to minimizing flood and drought risks in its cities. [ABSTRACT FROM AUTHOR]

The water-energy-food nexus is a topical subject for research and practice, reflecting the importance of these sectors for humankind and the complexity and magnitude of the challenges they are facing. While the nexus as a concept is not yet mature or fully tested in practice, it has already encouraged a range of approaches in a variety of contexts. This article provides a set of definitions recognizing three perspectives that see the nexus as an analytical tool, governance framework and as an emerging discourse. It discusses the implications that an international transboundary context brings to the nexus and vice versa. Based on a comparative analysis of three Asian regions--Central Asia, South Asia and the Mekong Region--and their related transboundary river basins, we propose that the transboundary context has three major implications: diversity of scales and perspectives, importance of state actors and importance of politics. Similarly, introducing the nexus as an approach in a transboundary context has a potential to provide new resources and approaches, alter existing actor dynamics and portray a richer picture of relationships. Overall, the significance of water-energy-food linkages and their direct impacts on water allocation mean that the nexus has the potential to complement existing approaches also in the transboundary river basins. [ABSTRACT FROM AUTHOR]