| 1. |
- Brandt, S. Anders, 1970-, et al.
(författare)
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Visualising DEM-related flood-map uncertainties using a disparity-distance equation algorithm
- 2016
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Ingår i: IAHS-AISH Proceedings and Reports. - Göttingen : Copernicus Publications on behalf of International Association of Hydrological Sciences (IAHS). ; , s. 153-159
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Konferensbidrag (refereegranskat)abstract
- The apparent absoluteness of information presented by crisp-delineated flood boundaries can lead tomisconceptions among planners about the inherent uncertainties associated in generated flood maps. Even mapsbased on hydraulic modelling using the highest-resolution digital elevation models (DEMs), and calibrated withthe most optimal Manning’s roughness (n) coefficients, are susceptible to errors when compared to actual floodboundaries, specifically in flat areas. Therefore, the inaccuracies in inundation extents, brought about by thecharacteristics of the slope perpendicular to the flow direction of the river, have to be accounted for. Instead ofusing the typical Monte Carlo simulation and probabilistic methods for uncertainty quantification, an empiricalbaseddisparity-distance equation that considers the effects of both the DEM resolution and slope was used tocreate prediction-uncertainty zones around the resulting inundation extents of a one-dimensional (1-D) hydraulicmodel. The equation was originally derived for the Eskilstuna River where flood maps, based on DEM dataof different resolutions, were evaluated for the slope-disparity relationship. To assess whether the equation isapplicable to another river with different characteristics, modelled inundation extents from the Testebo Riverwere utilised and tested with the equation. By using the cross-sectional locations, water surface elevations, andDEM, uncertainty zones around the original inundation boundary line can be produced for different confidences.The results show that (1) the proposed method is useful both for estimating and directly visualising modelinaccuracies caused by the combined effects of slope and DEM resolution, and (2) the DEM-related uncertaintiesalone do not account for the total inaccuracy of the derived flood map. Decision-makers can apply it to alreadyexisting flood maps, thereby recapitulating and re-analysing the inundation boundaries and the areas that areuncertain. Hence, more comprehensive flood information can be provided when determining locations whereextra precautions are needed. Yet, when applied, users must also be aware that there are other factors that caninfluence the extent of the delineated flood boundary.
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| 2. |
- Croke, B., et al.
(författare)
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Marrying Hydrological Modelling and Integrated Assessment for the needs of Water Resource Management
- 2014
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Ingår i: Proceedings of the International Association of Hydrological Sciences. - Bologna, Italy : IAHS. - 0144-7815 .- 2199-899X. - 9781907161421 ; 364, s. 351-356
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Tidskriftsartikel (refereegranskat)abstract
- Abstract This paper discusses the integration of hydrology with other disciplines using an Integrated Assessment (IA) and modelling approach to the management and allocation of water resources. Recent developments in the field of socio-hydrology aim to develop stronger relationships between hydrology and the human dimensions of Water Resource Management (WRM). This should build on an existing wealth of knowledge and experience of coupled human–water systems. To further strengthen this relationship and contribute to this broad body of knowledge, we propose a strong and durable “marriage” between IA and hydrology. The foundation of this marriage requires engagement with appropriate concepts, model structures, scales of analyses, performance evaluation and communication – and the associated tools and models that are needed for pragmatic deployment or operation. To gain insight into how this can be achieved, an IA case study in water allocation in the Lower Namoi catchment, NSW, Australia is presented.
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| 3. |
- Di Baldassarre, Giuliano, et al.
(författare)
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The interplay between human population dynamics and flooding in Bangladesh : a spatial analysis
- 2014
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Ingår i: Evolving Water Resources Systems. - : Copernicus GmbH. - 9781907161421 ; , s. 188-191
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Konferensbidrag (refereegranskat)abstract
- In Bangladesh, socio-economic and hydrological processes are both extremely dynamic and interrelated. Human population patterns are often explained as a response, or adaptation strategy, to physical events, e.g. flooding, salt-water intrusion, and erosion. Meanwhile, these physical processes are exacerbated, or mitigated, by diverse human interventions, e.g. river diversion, levees and polders. In this context, this paper describes an attempt to explore the complex interplay between floods and societies in Bangladeshi floodplains. In particular, we performed a spatially-distributed analysis of the interactions between the dynamics of human settlements and flood inundation patterns. To this end, we used flooding simulation results from inundation modelling, LISFLOOD-FP, as well as global datasets of population distribution data, such as the Gridded Population of the World (20 years, from 1990 to 2010) and HYDE datasets (310 years, from 1700 to 2010). The outcomes of this work highlight the behaviour of Bangladeshi floodplains as complex human water systems and indicate the need to go beyond the traditional narratives based on one-way cause effects, e.g. climate change leading to migrations.
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| 4. |
- Engström, Rebecka, et al.
(författare)
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Water impacts and water-climate goal conflicts of local energy choices – notes from a Swedish perspective
- 2018
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Ingår i: Proceedings of the International Association of Hydrological Sciences. - : Copernicus GmbH. - 2199-899X. ; 376, s. 25-33
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Tidskriftsartikel (refereegranskat)abstract
- To meet both the Paris Agreement on Climate Change and the UN Sustainable Development Goals (SDGs), nations, sectors, counties and cities need to move towards a sustainable energy system in the next couple of decades. Such energy system transformations will impact water resources to varying extents, depending on the transformation strategy and fuel choices. Sweden is considered to be one of the most advanced countries towards meeting the SDGs. This paper explores the geographical origin of and the current water use associated with the supply of energy in the 21 regional counties of Sweden. These energy-related uses of water represent indirect, but still relevant, impacts for water management and the related SDG on clean water and sanitation (SDG 6). These indirect water impacts are here quantified and compared to reported quantifications of direct local water use, as well as to reported greenhouse gas (GHG) emissions, as one example of other types of environmental impacts of local energy choices in each county. For each county, an accounting model is set up based on data for the local energy use in year 2010, and the specific geographical origins and water use associated with these locally used energy carriers (fuels, heat and electricity) are further estimated and mapped based on data reported in the literature and open databases. Results show that most of the water use associated with the local Swedish energy use occurs outside of Sweden. Counties with large shares of liquid biofuel exhibit the largest associated indirect water use in regions outside of Sweden. This indirect water use for energy supply does not unambiguously correlate with either the local direct water use or the local GHG emissions, although for the latter, there is a tendency towards an inverse relation. Overall, the results imply that actions for mitigation of climate change by local energy choices may significantly affect water resources elsewhere. Swedish counties are thus important examples of localities with large geographic zones of water influence due to their local energy choices, which may compromise water security and the possibility to meet water-related global goals in other world regions.
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| 5. |
- Hounkpatin, Ozias
(författare)
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Assessing the effect of soil parameterization in land use change impact modeling
- 2021
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Ingår i: Proceedings of IAHS. - : Copernicus GmbH. - 2199-899X. ; 384, s. 275-281
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Tidskriftsartikel (refereegranskat)abstract
- This study addresses the importance of integrating the effect of land use on soil infiltration rate into land use change impact modeling. Based on a validated version 9.05.04 of the Water balance Simulation Model-WaSiM (statistical quality measures > 0.7), and field measurement of the infiltration rate under cropland and fallow, sixteen model simulations were performed. The impact of land use change is computed comparing LULC status of years 1990 and 2013. The effect of soil parameterization is computed using a refined soil map integrating land use change impact of soil infiltration rate and a classic soil map not considering this interaction. The results show differences in model results as an effect of soil parameterization approaches, indicating that the model is sensitive to the integration of LULC related effects on soil hydraulic conductivity. These differences are more pronounced with increasing modeling time steps (24 and 28 h). The signal-to-noise-ratio indicates that, results achieved in LULC impact assessment with a classic and a refined soil parameterization are very comparable except for interflow.
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| 6. |
- Thakur, Chandni, et al.
(författare)
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Assessment of Hydrological Changes in Godavari River Basin Under the Impacts of El-Niño
- 2024
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Ingår i: Proceedings of the International Association of Hydrological Sciences (PIAHS). - : Copernicus Publications. - 2199-899X. ; 385, s. 203-209
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Tidskriftsartikel (refereegranskat)abstract
- El Niño–Southern Oscillation (ENSO) is the most prominent driver of the inter-annual variability of Indian summer monsoon rainfall (ISMR). This study focuses on understanding the hydrological variations in Godavari River Basin (GRB) due to the weakening of ISMR during El Niño years (1980–2008), using the variable infiltration capacity (VIC) model. The entire basin was discretized into 1325 uniform grids of resolution 0.15°×0.15° (about 16.65 km), and hydrological parameters of the basin were analysed at each grid level for various El Niño events. Based on the Oceanic Niño Index (ONI), obtained from National Oceanic and Atmospheric Administration (NOAA), El Niño events occurred in the past were subclassified into weak (2004 and 2006), moderate (1986, 1994 and 2002), strong (1987 and 1991) and very strong (1982, 1987) events. For this study, VIC model was run for the period 1980–2008 and a composite of El Niño and normal years (1981, 1985, 1989, 1990, 1992, 1993, 1996, 2001 and 2003) was prepared to assess the impacts of El Niño events on the hydrology of GRB. Our results showed a negative correlation of precipitation, abstractions and soil moisture with the increasing magnitude of El Niño events. The quantum of precipitation was reduced during El Niño years compared to normal years, which showed the basin's exposure to more frequent droughts during El Niño events.
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