Flood Early Warning and Risk Modelling

The evolution of mankind during the last 2 centuries has generated an ever growing thrive for increased production, for the need to create novel means to generate energy and for society to change into a more consumerism-oriented version [...

Flood Early Warning and Risk Modelling

The evolution of mankind during the last 2 centuries has generated an ever growing thrive for increased production, for the need to create novel means to generate energy and for society to change into a more consumerism-oriented version [...

Flood Early Warning and Risk Modelling

The evolution of mankind during the last 2 centuries has generated an ever growing thrive for increased production, for the need to create novel means to generate energy and for society to change into a more consumerism-oriented version [...]</jats:p

Groundwater Resources from Eastern Romania under Human and Climatic Pressure

Groundwater resources from a region may be subject to complex human and climatic pressure. The present study tries to analyze the human and climatic pressure on the groundwater resources from the eastern part of Romania, between 1983 and 2017, for seven groundwater bodies. Two parameters, the groundwater exploitation index (GWEI) and the Standardized Groundwater Index (SGI) for identifying hydrogeological droughts, were used to assess human and climatic pressure. The high values of GWEI show a significant increase in human pressure on water resources in recent decades, in lower and more populated areas, from the south and north part of de region, amid increasing investment in agriculture. In the case of climate pressure, the SGI values show significant values for the years 1983, 2000, 2007, and 2012. However, the overlap of hydrogeological droughts with an increase in human pressure can have a significant impact on the groundwater resources from this region, with negative effects in the mid and long term, under the growing effects of the regional climate changes.</jats:p

Multi-scale approach for different type of drought in temperate climatic conditions

AbstractDrought with its occurrence and manifestations at all levels of the natural components, yields both direct and indirect negative effects, on the ecological systems, water resources, social, as well as economic aspects of life. Therefore, any analysis that concerns this phenomenon, must be carried out at a multi-scalar level, addressing all manifestation levels (meteorological, hydrological, and hydrogeological drought). Standardized evaluation indices (for precipitation-SPI, evaporation-, -SPEI, streamflow-SDI and groundwater-SGI) have been used to analyze the evolution of the drought phenomena in Eastern Romania, for 1, 3, 6 and 12 months’ time-scales, applied to seven groundwater bodies. The results of the analysis complement the observations concerning the evolution of meteorological drought (using SPI and SPEI) in the East European region, by highlighting the drought sequences of the last two decades of the last century. Those are accompanied by the meteorological drought sequences which occurred on extensive areas, starting from 2007, until present, with direct effects in river discharge and increases in groundwater level depths. The Bravais–Pearson correlation coefficient shows a close connection between meteorological and hydrological drought (r ~ 0.45 to 0.68) and between hydrological and groundwater drought (r ~ 0.42 to 0.74) for wells with piezometric level under 5 m depth. In the larger context of climate scenarios which envision an increase in air temperature, and a decrease in the atmospheric hydrological input, the increase in the drought frequency is obvious, with direct effects on all-natural components that are dependent on the hydrological resources.</jats:p

Groundwater Resources from Eastern Romania under Human and Climatic Pressure

Groundwater resources from a region may be subject to complex human and climatic pressure. The present study tries to analyze the human and climatic pressure on the groundwater resources from the eastern part of Romania, between 1983 and 2017, for seven groundwater bodies. Two parameters, the groundwater exploitation index (GWEI) and the Standardized Groundwater Index (SGI) for identifying hydrogeological droughts, were used to assess human and climatic pressure. The high values of GWEI show a significant increase in human pressure on water resources in recent decades, in lower and more populated areas, from the south and north part of de region, amid increasing investment in agriculture. In the case of climate pressure, the SGI values show significant values for the years 1983, 2000, 2007, and 2012. However, the overlap of hydrogeological droughts with an increase in human pressure can have a significant impact on the groundwater resources from this region, with negative effects in the mid and long term, under the growing effects of the regional climate changes

GIS automation of large-scale flood vulnerability analysis for drainage basins, based on a single Digital Elevation Model

&amp;lt;p&amp;gt;In the context of climate change, probability of risk phenomena occurrence is more frequent and with greater intensity. This is especially valid for floods which cause significantly more damage and casualties, as flood-inducing conditions are met more often. The risk is emphasized by the fact that countless human settlements are located on the floodplain of river courses of different sizes and flow rates. The current study aims to detail an automatic GIS model that can easily compare drainage sub-basins of similar order, according to Horton-Strahler hierarchical classification, at large scale, for a given basin, based on morphometric parameters. This implies the use of a digital elevation model (DEM) as the only input layer, and setting a few parameters, in order to extract several quantifiable hydrological indicators, relevant to flood analysis. Some of the most relevant ones from the list are the elongation ratio, circularity ratio, relief ratio, roughness number, drainage density etc. All the functions have been integrated into a GIS tool, that would automatically aid in the fast creation of a final vector layer, that discerns between drainage basins with higher and lower degrees of relative vulnerability. This layer contains an attribute table with all the relevant parameters, as well as the result of the formula that assigns flood vulnerability values to each drainage basin, making possible the quantitative comparison between all the drainage sub-basins. The resulting table analysis is conducted in the background, based on the calculation of normalized values for each parameter, which are encompassed into a final vulnerability score. The model is easily applicable to most types of raster elevation layers, as long as they are in a projected coordinate system, regardless of pixel size. Furthermore, several functions were added to the model to mitigate potential errors that can occur in isolated cases, where the topography is particularly difficult to interpret by some native GIS tools. Therefore, this model is an easy to apply tool, that automatically identifies more vulnerable sub-basins, from a large drainage basin, over extended areas, with limited user-input, facilitating decision making in flood management, while providing quantifiable flood vulnerability results, in a very short period of time, without requiring extensive knowledge from the user.&amp;lt;/p&amp;gt;</jats:p