We investigate hydrology during a past climate slightly warmer than the present: the last interglacial (LIG). With daily output of preindustrial and LIG simulations from eight new climate models we force hydrological model PCR‐GLOBWB and in turn hydrodynamic model CaMa‐Flood. Compared to preindustrial, annual mean LIG runoff, discharge, and 100‐yr flood volume are considerably larger in the Northern Hemisphere, by 14%, 25%, and 82%, respectively. Anomalies are negative in the Southern Hemisphere. In some boreal regions, LIG runoff and discharge are lower despite higher precipitation, due to the higher temperatures and evaporation. LIG discharge is much higher for the Niger, Congo, Nile, Ganges, Irrawaddy, and Pearl and lower for the Mississippi, Saint Lawrence, Amazon, Paraná, Orange, Zambesi, Danube, and Ob. Discharge is seasonally postponed in tropical rivers affected by monsoon changes. Results agree with published proxies on the sign of discharge anomaly in 15 of 23 sites where comparison is possible.
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Over the past decades, various types of permeable pavements have been implemented in different municipalities in the Netherlands in order to improve infiltration capacity in urban areas and therewith being able to better treat stormwater runoff. With initial promising results, this adaptation measure seemed to be the solution for urban flooding due to extreme precipitation.However, in practice, foreseen infiltration capacities were usually not met, often due to unknown reasons. To better understand the functioning of permeable pavements in practice, we have studied - as part of the project Infiltrating Cities - over 100 existing permeable pavement installations in the Netherlands. At each location, infiltration capacity was tested through a full-scale infiltration testing procedure (flooded area about 40 m2) while conditional on-site factors were collected (location, age, type of permeable pavement, street-type, traffic density, vicinity of urban green, regular maintenance regime, etc.). By coupling this information we analyzed how these factors influence the infiltration capacity of permeable pavements in practice, e.g. through accelerated deterioration of infiltration capacity through time. In addition, we evaluated for a selected number of installations, how various types of maintenance may counteract this deterioration, hence improving the infiltration capacity of permeable pavements.
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Both climate change and human activity are the important drivers that can change hydrological cycle routs and affect the features of hydrological drought in river basins. The current study selects the Zayandeh Rud river Basin as a case study region in which to evaluate the influences of climate alteration and human activity on meteorological and hydrological drought based on the Standardized Precipitation Index (SPI) and Standardized Runoff Index (SRI) on different time scales. The generated local climatic data of future years (2006–2040), (2041–2075) and (2076–2100) under the severest scenario (RCP 8.5) from the CMIP5 climate model are selected and used for the hydrology model and water allocation model of WEAP to construct hydrological drought which also consider human activities. The results indicate that significant meteorological drought is expected to occur in the winter and spring months of January to June. However, the driest month for hydrological drought is in the summer and autumn (July to December) (e.g. no changes in seasonality of droughts compared to historic period). It is concluded that, in the results of this work, the human influences on projected hydrological drought have been outlined; they had been missed in many projections for future hydrological drought. However, this study confirms the previous study (Bierkens et al. 2012) which mentioned that human influences can account for future hydrological drought in areas of Asia, the Middle East and the Mediterranean. The results attained in this study are beneficial for examining how hydrological drought characterizations respond to climate alteration and human activity on several time scales, thereby providing scientific information for drought predicting and water resources management over various time scales under non-stationary circumstances.
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Evaluation of the hydrological performance of grassed swales usually needs long-term monitoring data. At present, suitable techniques for simulating the hydrological performance using limited monitoring data are not available. Therefore, current study aims to investigate the relationship between saturated hydraulic conductivity (Ks) fitting results and rainfall characteristics of various events series length. Data from a full-scale grassed swale (Enschede, the Netherlands) were utilized as long-term rainfall event series length (95 rainfall events) on the fitting outcomes. Short-term rainfall event series were extracted from these long-term series and used as input in fitting into a multivariate nonlinear model between Ks and its influencing rainfall indicators (antecedent dry days, temperature, rainfall, rainfall duration, total rainfall, and seasonal factor (spring, summer, autumn, and winter, herein refer as 1, 2, 3, and 4). Comparison of short-term and long-term rainfall event series fitting results allowed to obtain a representative short-term series that leads to similar results with those using long-term series. A cluster analysis was conducted based on the fitting results of the representative rainfall event series with their rainfall event characteristics using average values of influencing rainfall indicators. The seasonal index (average value of seasonal factors) was found to be the most representative short rainfall event series indicator. Furthermore, a Bayesian network was proposed in the current study to predict if a given short-term rainfall event series is representative. It was validated by a data series (58 rainfall events) from another full-scale grassed swale located in Utrecht, the Netherlands. Results revealed that it is quite promising and useful to evaluate the representativeness of short-term rainfall event series used for long-term hydrological performance evaluation of grassed swales.
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Peat swamp forests in Southeast Asia are under heavy pressure. Deforestation, forest degradation, wildfires, and drainage have damaged or destroyed substantial areas of the once extensive peat swamp forest formations. Several efforts are underway to rehabilitate degraded peat forests areas in order to restore some of the valuable ecosystem services these forested areas once provided. However, these efforts often result in (mixed)-plantations that only partly resemble the original peat forests. Information about these peat swamp forests' complex origin and ecology is needed to improve restoration outcomes further. Our paper analyses historical data from coastal peat swamp forests in Sarawak and Brunei and discusses the potential to use this as the reference value for intact peat forests. We describe the observed stand structure and species composition for pristine peat swamp forest, and we analyze the population structure of three dominant peat swamp forest species: Gonystylus bancanus (ramin), Dactylocladus stenostachys (jongkong) and Shorea albida (alan batu). We compare the historical data with data from recently measured, degraded peat swamp forests. We discuss our results in relation to processes of peat dome formation, nutrient availability and hydrology, and give recommendations for peat swamp forest management and restoration.
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In Eastern Africa, increasing climate variability and changing socioeconomic conditions are exacerbating the frequency and intensity of drought disasters. Droughts pose a severe threat to food security in this region, which is characterized by a large dependency on smallholder rain-fed agriculture and a low level of technological development in the food production systems. Future drought risk will be determined by the adaptation choices made by farmers, yet few drought risk models … incorporate adaptive behavior in the estimation of drought risk. Here, we present an innovative dynamic drought risk adaptation model, ADOPT, to evaluate the factors that influence adaptation decisions and the subsequent adoption of measures, and how this affects drought risk for agricultural production. ADOPT combines socio-hydrological and agent-based modeling approaches by coupling the FAO crop model AquacropOS with a behavioral model capable of simulating different adaptive behavioral theories. In this paper, we compare the protection motivation theory, which describes bounded rationality, with a business-as-usual and an economic rational adaptive behavior. The inclusion of these scenarios serves to evaluate and compare the effect of different assumptions about adaptive behavior on the evolution of drought risk over time. Applied to a semi-arid case in Kenya, ADOPT is parameterized using field data collected from 250 households in the Kitui region and discussions with local decision-makers. The results show that estimations of drought risk and the need for emergency food aid can be improved using an agent-based approach: we show that ignoring individual household characteristics leads to an underestimation of food-aid needs. Moreover, we show that the bounded rational scenario is better able to reflect historic food security, poverty levels, and crop yields. Thus, we demonstrate that the reality of complex human adaptation decisions can best be described assuming bounded rational adaptive behavior; furthermore, an agent-based approach and the choice of adaptation theory matter when quantifying risk and estimating emergency aid needs.
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Saturated hydraulic conductivity (Ks) of the filler layer in grassed swales are varying in the changing environment. In most of the hydrological models, Ks is assumed as constant or decrease with a clogging factor. However, the Ks measured on site cannot be the input of the hydrological model directly. Therefore, in this study, an Ensemble Kalman Filter (EnKF) based approach was carried out to estimate the Ks of the whole systems in two monitored grassed swales at Enschede and Utrecht, the Netherlands. The relationship between Ks and possible influencing factors (antecedent dry period, temperature, rainfall, rainfall duration, total rainfall and seasonal factors) were studied and a Multivariate nonlinear function was established to optimize the hydrological model. The results revealed that the EnKF method was satisfying in the Ks estimation, which showed a notable decrease after long-term operation, but revealed a recovery in summer and winter. After the addition of Multivariate nonlinear function of the Ks into hydrological model, 63.8% of the predicted results were optimized among the validation events, and compared with constant Ks. A sensitivity analysis revealed that the effect of each influencing factors on the Ks varies depending on the type of grassed swale. However, these findings require further investigation and data support.
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The ‘Grand Challenges’ of our times, like climate change, resource depletion, global inequity, and the destruction of wildlife and biodiversity can only be addressed by innovating cities. Despite the options of tele-working, tele-trading and tele-amusing, that allow people to participate in ever more activities, wherever they are, people are resettling in cities at an unprecedented speed. The forecasted ‘rurification’ of society did not occur. Technological development has drained rural society from its main source of income, agriculture, as only a marginal fraction of the labour force is employed in agriculture in the rich parts of the world. Moreover, technological innovation created new jobs in the IT and service sectors in cities. Cities are potentially far more resource efficient than rural areas. In a city transport distances are shorter, infrastructures can be applied to provide for essential services in a more efficient way and symbiosis might be developed between various infrastructures. However, in practice, urban infrastructures are not more efficient than rural infrastructures. This paper explores the reasons why. It digs into the reasons why the symbiotic options that are available in cities are not (sufficiently) utilised. The main reason for this is not of an economic nature: Infrastructure organisations are run by experts who are part of a strong paradigmatic community. Dependence on other organisations is regarded as limiting the infrastructure organisation’s freedom of action to achieve its own goals. Expert cultures are transferred in education, professional associations, and institutional arrangements. By 3 concrete examples of urban systems, the paper will analyse how various paradigms of experts co-evolved with evolving systems. The paper reflects on recent studies that identified professional education as the initiation into such expert paradigms. It will thereby relate lack of urban innovation to the monodisciplinary education of experts and the strong institutionalised character of expertise. https://doi.org/10.1007/978-3-319-63007-6_43 LinkedIn: https://www.linkedin.com/in/karelmulder/
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Nowadays, Nature-Based Solutions (NBSs) are developing as innovative multifunctional tools to maximize urban ecosystem services such as storm water preservation, reduction of runoff and flood protection, groundwater pollution prevention, biodiversity enhancement, and microclimate control. Gdańsk is one of the first Polish cities to widely introduce rain gardens (one example of an NBS) in different areas such as parks, city center, main crossroads, and car parks. They involve different technical innovations individually tailored to local architecture, including historic buildings and spaces. Gdańskie Wody, which is responsible for storm water management in the city, adopted a pioneering strategy and started the construction of the first rain garden in 2018. Currently, there are a dozen rain gardens in the city, and this organisation's policy stipulates the construction of NBSs in new housing estates without building rainwater drainage.Various types of rain gardens can be created depending on location characteristics such as geo-hydrology, as well as local conditions and needs. Furthermore, each of them might be equipped with specific technical solutions to improve the rain garden's function – for example, an oil separator or setter can be included to absorb the initial, most polluted runoff. During winter, the large amount of sodium chloride usually used to grit the roads may pose the greatest threat to biodiversity and plants. These installations have been included in a large rain garden in Gdańsk, located in the central reservation of the main streets in the city center.This work presents various technical considerations and their impact on ecosystem functions, and the urban circularity challenges provided by rain gardens operating in different technologies and surroundings. The precipitation quantity and the following infiltration rate were estimated by installing pressure transducers. Furthermore, mitigation of the urban heat island was analysed based on remote sensing images.
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Bij zijn inauguratie presenteerde Luewton Agostinho een globale visie op watertechnologie, de fysische principes die hierbij betrokken zijn en de uitdagingen, behoeften en conflicten bij het wetenschappelijk en toegepast onderzoek
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