Time filter

Source Type

Montanari A.,University of Bologna | Di Baldassarre G.,UNESCO-IHE Institute for Water Education
Advances in Water Resources | Year: 2013

Observation uncertainty is nowadays recognized as a serious issue undermining the reliability of hydrological studies. For instance, many recent contributions show that river flow observations are affected by errors that may reach 25% even when state-of-the-art measurement techniques are adopted. Yet, there is still little guidance by the literature on the most appropriate modelling strategies to be adopted under observation uncertainty. We carried out a series of simulation experiments and explored how the selection of appropriate model complexity can help reduce the impact of observation uncertainty. We found that model structure plays a relevant role and, in particular, a description of the relevant physical processes that come into play can effectively contribute to limit the impact of data errors and therefore significantly reduce overall uncertainty. © 2012 Elsevier Ltd.

Ramos M.H.,IRSTEA | Van Andel S.J.,UNESCO-IHE Institute for Water Education | Pappenberger F.,ECMWF
Hydrology and Earth System Sciences | Year: 2013

The last decade has seen growing research in producing probabilistic hydro-meteorological forecasts and increasing their reliability. This followed the promise that, supplied with information about uncertainty, people would take better risk-based decisions. In recent years, therefore, research and operational developments have also started focusing attention on ways of communicating the probabilistic forecasts to decision-makers. Communicating probabilistic forecasts includes preparing tools and products for visualisation, but also requires understanding how decision-makers perceive and use uncertainty information in real time. At the EGU General Assembly 2012, we conducted a laboratory-style experiment in which several cases of flood forecasts and a choice of actions to take were presented as part of a game to participants, who acted as decision-makers. Answers were collected and analysed. In this paper, we present the results of this exercise and discuss if we indeed make better decisions on the basis of probabilistic forecasts. © Author(s) 2013.

McClain M.E.,UNESCO-IHE Institute for Water Education | McClain M.E.,Technical University of Delft
Ambio | Year: 2013

Sustainable development in Africa is dependent on increasing use of the continent's water resources without significantly degrading ecosystem services that are also fundamental to human wellbeing. This is particularly challenging in Africa because of high spatial and temporal variability in the availability of water resources and limited amounts of total water availability across expansive semi-arid portions of the continent. The challenge is compounded by ambitious targets for increased water use and a rush of international funding to finance development activities. Balancing development with environmental sustainability requires (i) understanding the boundary conditions imposed by the continent's climate and hydrology today and into the future, (ii) estimating the magnitude and spatial distribution of water use needed to meet development goals, and (iii) understanding the environmental water requirements of affected ecosystems, their current status and potential consequences of increased water use. This article reviews recent advancements in each of these topics and highlights innovative approaches and tools available to support sustainable development. While much remains to be learned, scientific understanding and technology should not be viewed as impediments to sustainable development on the continent. © 2012 The Author(s).

Kelderman P.,UNESCO-IHE Institute for Water Education
Water, Air, and Soil Pollution | Year: 2012

This paper presents an overview of a long-term study on sediment pollution in the city canals of Delft, the Netherlands. This pollution was most evident for the inner city canal system, with copper, lead, zinc, and polycyclic aromatic hydrocarbons (PAHs) as main pollutants. Sediments of the outer city canals generally had a much better quality. Pollution levels, mutual correlations, and spatial variations were investigated for the various sediment parameters. Also, heavy metal binding forms onto Delft sediments were assessed with the help of sequential extraction techniques; results were found to be in line with expected preferential physicochemical binding processes. Input of sediments into the Delft inner city canals was shown to be largely driven by busy shipping traffic on the main canal surrounding the inner city. Mass balances for the inner city were used to quantify internal and external pollution sources; 65-85 % of the heavy metal pollution can be attributed to sources outside the Delft area. As shown by factor and cluster analyses, it is highly probable that these external sources derive from the river Rhine. A gradual improvement of the sediment quality has set in; it is expected that, due to further pollution abatement measures, this improvement will continue over the years to come. With respect to the ship-induced sediment input into the inner city canals, it was estimated that a reduction of ship velocities to <1.5 m/s will bring down the sediment input mentioned above to about 85 %. © 2012 Springer Science+Business Media B.V.

Gupta J.,VU University Amsterdam | Gupta J.,UNESCO-IHE Institute for Water Education
Current Opinion in Environmental Sustainability | Year: 2012

Global forest governance is moving incrementally forward. REDD+ is the latest forest instrument being promoted globally as a cost-effective mechanism. This paper addresses the question: Does a glocal (global to local to global) analysis of forest policies lead to the conclusion that REDD+ can deliver a win-win situation as proponents claim? Using a literature review and focusing on four countries, this paper argues that REDD+ can potentially address deforestation and climate change by mobilizing financial and human resources, and help developed countries through cost-effective measures and developing countries by channeling resources to them. However, there is a risk that REDD+ may become a 'lose-lose' instrument leading to irreversible commodification and tradeability of forests, exacerbating North-South conflicts, and marginalizing local communities. © 2012 Elsevier B.V.

Discover hidden collaborations