Performing Hydrological Monitoring at a National Scale by Exploiting Rain-Gauge and Radar Networks: The Italian Case

Hydrological monitoring systems relying on radar data and distributed hydrological models are now feasible at large-scale and represent effective early warning systems for flash floods. Here we describe a system that allows hydrological occurrences in terms of streamflow at a national scale to be monitored. We then evaluate its operational application in Italy, a country characterized by various climatic conditions and topographic features. The proposed system exploits a modified conditional merging (MCM) algorithm to generate rainfall estimates by blending data from national radar and rain-gauge networks. Then, we use the merged rainfall fields as input for the distributed and continuous hydrological model, Continuum, to obtain real-time streamflow predictions. We assess its performance in terms of rainfall estimates from MCM, using cross-validation and comparison with a conditional merging technique at an event-scale. We also assess its performance against rainfall fields from ground-based data at catchment-scale. We further evaluate the performance of the hydrological system in terms of streamflow against observed data (relative error on high flows less than 25% and Nash–Sutcliffe Efficiency greater than 0.5 for 72% and 46% of the calibrated study sections, respectively). These results, therefore, confirm the suitability of such an approach, even at national scale, over a wide range of catchment types, climates, and hydrometeorological regimes, and for operational purposes.

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Riparian ecosystem in the alpine connectome. Terrestrial-aquatic and terrestrial-terrestrial interactions in high elevation lakes

10.1101/035576 ◽

2015 ◽

Cited By ~ 2

Author(s):

Dragos G Zaharescu ◽

Antonio Palanca-Soler ◽

Peter S Hooda ◽

Catalin Tanase ◽

Carmen I Burghelea ◽

...

Keyword(s):

Climate Change ◽

Environmental Change ◽

Large Scale ◽

Water Saturation ◽

Catchment Scale ◽

Landscape Elements ◽

Riparian Ecosystem ◽

Wide Range ◽

Terrestrial Environments ◽

Surrounding Landscape

Alpine regions are under increased attention worldwide do their role in storing freshwater of high quality and their high sensitivity to climate change - comparable only to the poles. Riparian ecosystems in such regions, integrating water and nutrient fluxes from aquatic and terrestrial environments, host a disproportionally rich biodiversity, despite experiencing severe climate and nutrient restrictions. With climate change rapidly encroaching in the alpine biome, it is important to fully understand how the lake and its surrounding landscape elements sustain such rich ecosystems, before their functional connectivity could be seriously severed. A total of 189 glacial origin lakes in the Central Pyrenees were surveyed to test how key elements of lake and terrestrial environments work together at different scales to shape the riparian plant composition. Secondly, we evaluated how these ecotope features drive the formation of riparian communities potentially sensitive to environmental change, and assessed their habitat distribution. At each lake plant taxonomic composition was assessed together with elemental composition of water and sediment and ecosystem-relevant geographical factors. At macroscale vegetation composition responded to pan-climatic gradients altitude and latitude, which captured, in a narrow geographic area the transition between large European climatic zones. Hydrodynamics was the main catchment-scale factor connecting riparian vegetation with large-scale water fluxes, followed by topography and geomorphology. Lake sediment Mg and Pb, and water Mn and Fe contents reflected local connections with nutrient availability, and water saturation of the substrate. Community analysis identified four keystone plant communities of large niche breadths, present in a wide range of habitats, from (i) damp environments, (ii) snow bed-silicate bedrock, (iii) wet heath, and (iv) limestone bedrock. With environmental change advancing in the alpine biome, this study provides critical information on fundamental linkages between riparian ecosystem and surrounding landscape elements, which could prove invaluable in assessing future biomic impacts.

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Water-balance response to climate variability, a small-to-large scale Italian dataset

10.5194/egusphere-egu21-4674 ◽

2021 ◽

Author(s):

Giulia Bruno ◽

Francesco Avanzi ◽

Simone Gabellani ◽

Luca Ferraris ◽

Edoardo Cremonese ◽

...

Keyword(s):

Water Balance ◽

Water Resource Management ◽

Large Scale ◽

Hydrological Cycle ◽

Climatic Variability ◽

Remote Sensing Data ◽

Data Availability ◽

Catchment Scale ◽

Wide Range ◽

Mean Square Errors

Understanding how deficit of precipitation impacts the hydrological cycle is of growing interest and is essential for water resource management. It has been recently observed that the relationship between precipitation and runoff during droughts is subjected to a shift in the sense that the predicted runoff is much less than the one expected due to the deficit in precipitation. Unraveling why this occurs requires an accurate knowledge of all the components of the water balance equation. However, large-scale and consistent samples of precipitation, runoff, evapotranspiration, ET and change in storage have always been challenging to collect. Here, we hypothesized that blending ground-based and remote-sensing data products could fill this gap. We present a countrywide dataset of catchment-scale water balance, covering the last 10 water years in Italy. Italy shows a broad variety of climatic and topographic features and faced several droughts over recent years. We use ground-based daily runoff data, interpolated precipitation maps, and a remote-sensed daily evapotranspiration dataset from the LSASAF ET product. The ET dataset is additionally compared with flux towers data across the country, obtaining root mean square errors on the order of 30 mm/month. Lastly, changes in storage are estimated to close the water balance. More than 100 catchments - including the major Italian basins - are selected, according to data availability and reliability. These catchments cover a wide range of size, morphologic and climatic characteristics.&#160;This dataset is a strategic source of information to analyze catchment-scale runoff, ET and storage response to climatic variability across climates and landscapes.

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Temporal and spatial evaluation of satellite-based rainfall estimates across the complex topographical and climatic gradients of Chile

Hydrology and Earth System Sciences ◽

10.5194/hess-21-1295-2017 ◽

2017 ◽

Vol 21 (2) ◽

pp. 1295-1320 ◽

Cited By ~ 100

Author(s):

Mauricio Zambrano-Bigiarini ◽

Alexandra Nauditt ◽

Christian Birkel ◽

Koen Verbist ◽

Lars Ribbe

Keyword(s):

Grid Cell ◽

Catchment Scale ◽

The Real ◽

Wide Range ◽

Northern Regions ◽

Specific Assessment ◽

Spatio Temporal ◽

Rain Events ◽

A Site ◽

Rainfall Estimates

Abstract. Accurate representation of the real spatio-temporal variability of catchment rainfall inputs is currently severely limited. Moreover, spatially interpolated catchment precipitation is subject to large uncertainties, particularly in developing countries and regions which are difficult to access. Recently, satellite-based rainfall estimates (SREs) provide an unprecedented opportunity for a wide range of hydrological applications, from water resources modelling to monitoring of extreme events such as droughts and floods.This study attempts to exhaustively evaluate – for the first time – the suitability of seven state-of-the-art SRE products (TMPA 3B42v7, CHIRPSv2, CMORPH, PERSIANN-CDR, PERSIAN-CCS-Adj, MSWEPv1.1, and PGFv3) over the complex topography and diverse climatic gradients of Chile. Different temporal scales (daily, monthly, seasonal, annual) are used in a point-to-pixel comparison between precipitation time series measured at 366 stations (from sea level to 4600 m a.s.l. in the Andean Plateau) and the corresponding grid cell of each SRE (rescaled to a 0.25° grid if necessary). The modified Kling–Gupta efficiency was used to identify possible sources of systematic errors in each SRE. In addition, five categorical indices (PC, POD, FAR, ETS, fBIAS) were used to assess the ability of each SRE to correctly identify different precipitation intensities.Results revealed that most SRE products performed better for the humid South (36.4–43.7° S) and Central Chile (32.18–36.4° S), in particular at low- and mid-elevation zones (0–1000 m a.s.l.) compared to the arid northern regions and the Far South. Seasonally, all products performed best during the wet seasons (autumn and winter; MAM–JJA) compared to summer (DJF) and spring (SON). In addition, all SREs were able to correctly identify the occurrence of no-rain events, but they presented a low skill in classifying precipitation intensities during rainy days. Overall, PGFv3 exhibited the best performance everywhere and for all timescales, which can be clearly attributed to its bias-correction procedure using 217 stations from Chile. Good results were also obtained by the research products CHIRPSv2, TMPA 3B42v7 and MSWEPv1.1, while CMORPH, PERSIANN-CDR, and the real-time PERSIANN-CCS-Adj were less skillful in representing observed rainfall. While PGFv3 (currently available up to 2010) might be used in Chile for historical analyses and calibration of hydrological models, the high spatial resolution, low latency and long data records of CHIRPS and TMPA 3B42v7 (in transition to IMERG) show promising potential to be used in meteorological studies and water resource assessments. We finally conclude that despite improvements of most SRE products, a site-specific assessment is still needed before any use in catchment-scale hydrological studies.

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Satellite Rainfall Estimates for Debris Flow Prediction: An Evaluation Based on Rainfall Accumulation–Duration Thresholds

Journal of Hydrometeorology ◽

10.1175/jhm-d-17-0052.1 ◽

2017 ◽

Vol 18 (8) ◽

pp. 2207-2214 ◽

Cited By ~ 12

Author(s):

E. I. Nikolopoulos ◽

E. Destro ◽

V. Maggioni ◽

F. Marra ◽

M. Borga

Keyword(s):

Debris Flow ◽

Early Warning Systems ◽

Global Scale ◽

Rain Gauge ◽

Coverage Problem ◽

Rainfall Thresholds ◽

Estimation Uncertainty ◽

Flow Prediction ◽

Definition Of ◽

Rainfall Estimates

Abstract Rainfall thresholds are often used in early warning systems to identify rainfall conditions that, when reached or exceeded, are likely to result in debris flows. Rain gauges are typically used for the definition of these thresholds. However, in mountainous areas in situ observations are often sparse or nonexistent. Satellite-based rainfall estimates offer a solution to overcome the coverage problem at the global scale but are associated with significant estimation uncertainty. Evaluating satellite-based rainfall thresholds is thus necessary to understand their potential and limitations. In this work, an intercomparison among satellite-based precipitation products is presented in the context of estimating rainfall thresholds for debris flow prediction. The study is performed for the upper Adige River basin in the eastern Italian Alps during 2000–10. Large differences are observed between event-based characteristics (event duration and magnitude) derived from rain gauge and satellite-based estimates, revealing considerable interproduct variability in the debris flow–triggering rainfall characteristics. The parameters of the satellite-based thresholds differ less than 30% from the corresponding rain gauge–based parameters. Results further suggest that the adjustment of satellite-based estimates (either gauge based or by applying an error model) together with spatial resolution has an important impact on the estimation of the accumulation–duration thresholds.

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Yield and Palatability of Potential Indigenous Leafy Vegetable of Cold Arid trans-Himalayan Ladakh, India

Defence Life Science Journal ◽

10.14429/dlsj.3.12567 ◽

2018 ◽

Vol 3 (2) ◽

pp. 136 ◽

Cited By ~ 1

Author(s):

Tsewang Rinchen ◽

Narendra Singh ◽

Samar Bahadur Maurya

Keyword(s):

Large Scale ◽

Consumer Preference ◽

Morphological Characters ◽

Climatic Conditions ◽

Native People ◽

Leafy Vegetables ◽

Yield Potential ◽

Fagopyrum Tataricum ◽

Amaranthus Cruentus ◽

Wide Range

Not much attention has been paid to a wide range of indigenous leafy vegetables that can grow in high altitude harsh climatic conditions with minimal care. Therefore, a study was carried out on yield potential and palatability of indigenous leafy vegetables (ILV) that grows in trans-Himalayan Ladakh. Seven ILV viz. Fagopyrum tataricum, Rumex patientia, Fagopyrum esculentum, Amaranthus cruentus, Malva vertisilester, Lepidium latifolium and Atriplex hortensis that are being used by native people of Ladakh were recorded for their morphological characters, earliness, yield and other consumer preference traits. The highest yield was recorded for A. hortensis (1.80±0.06 kg/m2). The study suggested that A. hortensis and A. crunteus have high palatability and are most preferred by the consumers. Yield potential of the cold hardy A. hortensis is significantly higher and it is an early maturing crop. Therefore, detail studies on A. hortensis are required, and efforts need to be made for large scale cultivation of the species.

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Temporal and spatial evaluation of satellite-based rainfall estimates across the complex topographical and climatic gradients of Chile

10.5194/hess-2016-453 ◽

2016 ◽

Cited By ~ 1

Author(s):

Mauricio Zambrano-Bigiarini ◽

Alexandra Nauditt ◽

Christian Birkel ◽

Koen Verbist ◽

Lars Ribbe

Keyword(s):

Water Resources ◽

Grid Cell ◽

High Elevation ◽

Catchment Scale ◽

Wide Range ◽

Northern Regions ◽

Spatio Temporal ◽

Rain Events ◽

A Site ◽

Rainfall Estimates

Abstract. Accurate representation of the real spatio-temporal variability of catchment rainfall inputs is currently severely limited. Moreover, spatially interpolated catchment precipitation is subject to large uncertainties, particularly in developing countries and regions which are difficult to access (e.g., high elevation zones). Recently, satellite-based rainfall estimates (SRE) provide an unprecedented opportunity for a wide range of hydrological applications, from water resources modelling to monitoring of extreme events such as droughts and floods. This study attempts to exhaustively evaluate -for the first time- the suitability of seven state-of-the-art SRE products (TMPA 3B42v7, CHIRPSv2, CMORPH, PERSIANN-CDR, PERSIAN-CCS-adj, MSWEPv1.1 and PGFv3) over the complex topography and diverse climatic gradients of Chile. Different temporal scales (daily, monthly, seasonal, annual) are used in a point-to-pixel comparison between precipitation time series measured at 366 stations (from sea level to 4600 m a.s.l. in the Andean Plateau) and the corresponding grid cell of each SRE. The modified Kling-Gupta efficiency was used to identify possible sources of systematic errors in each SRE. In addition, several categorical indices were used to assess the ability of each SRE to correctly identify different precipitation intensities. Results revealed that most SRE products performed better for the humid South (36.4–43.7° S) and Central Chile (32.18–36.4° S), in particular at low- and mid-elevation zones (0–1000 m a.s.l.) compared to the arid northern regions and the Far South. Seasonally, all products performed best during the wet seasons (MAM-JJA) compared to summer (DJF) and autumn (SON). In addition, all SREs were able to correctly identify the occurrence of no rain events, but they presented a low skill in classifying precipitation intensities during rainy days. Overall, PGFv3 exhibited the best performance everywhere and for all time scales, which can be clearly attributed to its bias-correction procedure using 217 stations from Chile. Good results were also obtained by CHIRPSv2, TMPA 3B42v7 and MSWEPv1.1, while CMORPH, PERSIANN-CDR and PERSIANN-CCS-adj were not able to represent observed rainfall. While PGFv3 (currently available up to 2010) might be used in Chile for historical analyses and calibration of hydrological models, the high spatial resolution, low latency and long data records of CHIRPS and TMPA 3B42v7 (in transition to IMERG) show promising potential to be used in meteorological studies and water resources assessments. We finally conclude that despite improvements of most SRE products, a site-specific assessment is still needed before any use in catchment-scale hydrological studies.

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Electron microscopy study of reactively sputter-deposited Ti/N films on silicon

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100131449 ◽

1992 ◽

Vol 50 (2) ◽

pp. 1362-1363

Author(s):

V. C. Kannan ◽

A. K. Singh ◽

R. B. Irwin ◽

S. Chittipeddi ◽

F. D. Nkansah ◽

...

Keyword(s):

Integrated Circuits ◽

Large Scale ◽

Hexagonal Phase ◽

Microscopy Study ◽

Electron Microscopy Study ◽

Process Conditions ◽

Tin Films ◽

Wide Range ◽

Fcc Phase ◽

Circuits Vlsi

Titanium nitride (TiN) films have historically been used as diffusion barrier between silicon and aluminum, as an adhesion layer for tungsten deposition and as an interconnect material etc. Recently, the role of TiN films as contact barriers in very large scale silicon integrated circuits (VLSI) has been extensively studied. TiN films have resistivities on the order of 20μ Ω-cm which is much lower than that of titanium (nearly 66μ Ω-cm). Deposited TiN films show resistivities which vary from 20 to 100μ Ω-cm depending upon the type of deposition and process conditions. TiNx is known to have a NaCl type crystal structure for a wide range of compositions. Change in color from metallic luster to gold reflects the stabilization of the TiNx (FCC) phase over the close packed Ti(N) hexagonal phase. It was found that TiN (1:1) ideal composition with the FCC (NaCl-type) structure gives the best electrical property.

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THE SOME QUESTIONS OF AUTONOMOUS MOTION AND MANAGEMENT OF LAND-MOBILE ROBOTIC COMPLEXES FOR UKRAINIAN GROUND FORCESE

Collection of scientific works of Odesa Military Academy ◽

10.37129/2313-7509.2019.11.53-58 ◽

2019 ◽

pp. 53-58

Author(s):

О. Кravchuk ◽

V. Symonenkov ◽

I. Symonenkova ◽

O. Hryhorev

Keyword(s):

Large Scale ◽

Armed Forces ◽

Distributed Information ◽

Wide Range ◽

Highly Effective ◽

Information Management Systems ◽

Robotic Devices ◽

Principles And Standards ◽

And Control ◽

The Eu

Today, more than forty countries of the world are engaged in the development of military-purpose robots. A number of unique mobile robots with a wide range of capabilities are already being used by combat and intelligence units of the Armed forces of the developed world countries to conduct battlefield intelligence and support tactical groups. At present, the issue of using the latest information technology in the field of military robotics is thoroughly investigated, and the creation of highly effective information management systems in the land-mobile robotic complexes has acquired a new phase associated with the use of distributed information and sensory systems and consists in the transition from application of separate sensors and devices to the construction of modular information subsystems, which provide the availability of various data sources and complex methods of information processing. The purpose of the article is to investigate the ways to increase the autonomy of the land-mobile robotic complexes using in a non-deterministic conditions of modern combat. Relevance of researches is connected with the necessity of creation of highly effective information and control systems in the perspective robotic means for the needs of Land Forces of Ukraine. The development of the Armed Forces of Ukraine management system based on the criteria adopted by the EU and NATO member states is one of the main directions of increasing the effectiveness of the use of forces (forces), which involves achieving the principles and standards necessary for Ukraine to become a member of the EU and NATO. The inherent features of achieving these criteria will be the transition to a reduction of tasks of the combined-arms units and the large-scale use of high-precision weapons and land remote-controlled robotic devices. According to the views of the leading specialists in the field of robotics, the automation of information subsystems and components of the land-mobile robotic complexes can increase safety, reliability, error-tolerance and the effectiveness of the use of robotic means by standardizing the necessary actions with minimal human intervention, that is, a significant increase in the autonomy of the land-mobile robotic complexes for the needs of Land Forces of Ukraine.

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Stirring and aeration system for the upgrading of small waste water treatment plants

Water Science & Technology ◽

10.2166/wst.1994.0600 ◽

1994 ◽

Vol 29 (12) ◽

pp. 149-156 ◽

Cited By ~ 4

Author(s):

Marcus Höfken ◽

Katharina Zähringer ◽

Franz Bischof

Keyword(s):

Waste Water ◽

Water Treatment ◽

Large Scale ◽

Waste Water Treatment ◽

Water Treatment Plants ◽

Waste Water Treatment Plants ◽

Basic Fluid ◽

Aeration System ◽

Technical Realization ◽

Wide Range

A novel agitating system has been developed which allows for individual or combined operation of stirring and aeration processes. Basic fluid mechanical considerations led to the innovative hyperboloid design of the stirrer body, which ensures high efficiencies in the stirring and the aeration mode, gentle circulation with low shear forces, excellent controllability, and a wide range of applications. This paper presents the basic considerations which led to the operating principle, the technical realization of the system and experimental results in a large-scale plant. The characteristics of the system and the differences to other stirring and aeration systems are illustrated. Details of the technical realization are shown, which conform to the specific demands of applications in the biological treatment of waste water. Special regard is given to applications in the upgrading of small compact waste water treatment plants.

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Thin structure of heterogeneous and multiphase fluid flows

Proceedings of the Mavlyutov Institute of Mechanics ◽

10.21662/uim2012.1.036 ◽

2012 ◽

Vol 9 (1) ◽

pp. 175-180

Author(s):

Yu.D. Chashechkin

Keyword(s):

Large Scale ◽

Fundamental System ◽

Fluid Flows ◽

Regular Solutions ◽

Flow Models ◽

Group Methods ◽

Wide Range ◽

Thin Structure ◽

Multiphase Fluid ◽

Complete Solutions

According to the results of visualization of streams, the existence of structures in a wide range of scales is noted: from galactic to micron. The use of a fundamental system of equations is substantiated based on the results of comparing symmetries of various flow models with the usage of theoretical group methods. Complete solutions of the system are found by the methods of the singular perturbations theory with a condition of compatibility, which determines the characteristic equation. A comparison of complete solutions with experimental data shows that regular solutions characterize large-scale components of the flow, a rich family of singular solutions describes formation of the thin media structure. Examples of calculations and observations of stratified, rotating and multiphase media are given. The requirements for the technique of an adequate experiment are discussed.

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