Shifting level modelling of hydrologic series

Abstract:The objective of this paper was to analyze the temporal and spatial trends in annual and seasonal precipitation in Slovakia utilizing 487 gauging station data collected statewide in the period from 1981 to 2013. The nonparametric Mann-Kendall (MK) statistical test, which has been widely used to assess the significance of trends in hydrological time series, was applied to detect the significant trends. The Theil-Sen (TS) approach was applied to quantify the trend magnitude, and the Sequential Mann-Kendall (SQMK) test was used to detect abrupt temporal trend shifts. In general, precipitation data in the study area have not changed during the last 33 years, and there are no big gaps. However, predominantly increasing trends in precipitation time series were found at most of the gauging stations in Slovakia. The results corroborate previous climatic studies in the area of central Europe. In Slovakia, there is evidence of different rain distribution from the monthly point of view. Decreasing trends were detected in December in the northern part of Slovakia, while the central and southern parts revealed increasing trends. Most of the stations showed increasing summer precipitation trends, especially in July. It is expected that the findings of this comprehensive study of precipitation trends over Slovakia will produce more insights for the understanding of the regional hydrological behavior in Slovakia over the last several decades.

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“…The lag-k serial correlation coefficient (r k ) of the detrended series Y t was computed according to Salas et al [75]:…”

Section: Discussionmentioning

confidence: 99%

Precipitation Trends over Slovakia in the Period 1981–2013

Zeleňáková

Vido

Portela

et al. 2017

Water

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“…Among the set of alternative modeling approaches (autoregressive models, neural networks, extremely randomize trees, etc. ), linear periodic PAR(1) models [Salas et al, 1980] were identified because they are able to provide good forecasts of the inflow processes according to the adopted monthly time step, see the explained variance in Table 2. In particular, the interannual variability characterizing the inflows in the Zambezi system [Rocha and Simmonds, 1997;Mazvimavi and Wolski, 2006] has limited impacts on the considered objectives and it can be captured by autoregressive models.…”

Section: Zambezi River Agent-based Modelmentioning

confidence: 99%

Assessing the value of cooperation and information exchange in large water resources systems by agent‐based optimization

Giuliani

Castelletti

2013

Water Resources Research

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[1] Many large-scale water resources systems, especially in transboundary contexts, are characterized by the presence of several and conflicting interests and managed by multiple, institutionally independent decision makers. These systems are often studied adopting a centralized approach based on the assumption of full cooperation and information exchange among the involved parties. Such a perspective is conceptually interesting to quantify the best achievable performance but might have little practical impact given the real political and institutional setting. In this work, we propose a novel decision-analytic framework based on multiagent systems to model and analyze different levels of cooperation and information exchange among multiple decision makers. The Zambezi River basin is used as a case study. According to the proposed agent-based optimization approach, each agent represents a decision maker, whose decisions are defined by an explicit optimization problem considering only the agent's local interests. The economic value of information exchange is estimated comparing a noncooperative setting, where agents act independently, with the first basic level of cooperation, i.e., coordination, characterized by full information exchange. The economic value of cooperation is also estimated by comparison with the ideal, fully cooperative management of the system. Results show that coordination, obtained with complete information exchange, allows the downstream agents to better adapt to the upstream behaviors. The impact of information exchange depends on the objective considered, and we show coordination to be particularly beneficial to environmental interests.Citation: Giuliani, M., and A. Castelletti (2013), Assessing the value of cooperation and information exchange in large water resources systems by agent-based optimization, Water Resour. Res., 49,[3912][3913][3914][3915][3916][3917][3918][3919][3920][3921][3922][3923][3924][3925][3926]

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“…Secondly, a historical flood record will be constructed for the downstream city of Carlisle to put the shorter record into a longer timescale context. several reasons including where recording equipment failed to record a river stage, the effects of extreme river flows and the loss of data due to downloading or computer storage problems (Salas, 1993). The approach used for record augmentation (Matalas and Jacobs, 1964) in this research is outlined below and is based on the techniques recommended by the Flood Estimation Handbook (FSR, 1975;FEH, 1999).…”

Section: Data Pre-treatmentmentioning

confidence: 99%

Rural land management impacts on catchment scale flood risk

Pattison¹

2010

Role of Hydrology in Managing Consequences of a Changing Global Environment

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The full-text may be used and/or reproduced, and given to third parties in any format or medium, without prior permission or charge, for personal research or study, educational, or not-for-pro t purposes provided that:• a full bibliographic reference is made to the original source• a link is made to the metadata record in Durham E-Theses• the full-text is not changed in any way The full-text must not be sold in any format or medium without the formal permission of the copyright holders.Please consult the full Durham E-Theses policy for further details. Most approaches to this problem aim to upscale from individual grid cells to whole catchments, something that restricts the complexity of possible process representation, produces models that may not be parsimonious with the data needed to calibrate them and, faced with data uncertainties, provides computational limitations on the extent to which model uncertainty can be fully explored. Rather than upscaling to problems of concern, this thesis seeks to downscale from locations of known flood risk, as a means of identifying where land use management changes might be beneficial and then uses numerical modelling to identify the kinds of management changes required in those downscaled locations. Thus, the aim of this thesis is to test an approach to understanding the impacts of rural land management upon flood risk based upon catchment-to-source downscaling.This thesis uses the case study of the River Eden catchment (2400 km 2 ) as a test (1) it was shown to have a significant impact on downstream flood risk; and (2) it had range of data and information needed for modelling land use changes.The second part of this thesis explored the land management scenarios that could be used to reduce flood risk at the catchment scale. The scenarios to be tested were determined through a stakeholder participation approach, whereby workshops were held to brainstorm and prioritise land management options, and then to identify specific locations within the Eamont sub-catchment where they could tested. There were two main types of land management scenarios chosen: (1) landscape-scale changes, including afforestation and compaction; and (2) corresponding to a 5.8% decrease in peak discharge. A key conclusion is that land management practices have been shown to have an effect on catchment scale flooding, even for extreme flood events. However, the effect of land management scenarios are both spatially and temporally dependent i.e. the same land management practice has different effects depending on where it is implemented, and when implemented in the same location has different effects on different flood events.

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Shifting level modelling of hydrologic series

Cited by 269 publications

References 14 publications

Precipitation Trends over Slovakia in the Period 1981–2013

Precipitation Trends over Slovakia in the Period 1981–2013

Assessing the value of cooperation and information exchange in large water resources systems by agent‐based optimization

Rural land management impacts on catchment scale flood risk

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