Effect Of Different Hydrological Model Structures On The Assimilation Of Distributed Uncertain Observations

The reliable evaluation of the flood forecasting is a crucial problem for assessing flood risk and consequent damages. Different hydrological models (distributed, semi-distributed or lumped) have been proposed in order to deal with this issue. The choice of the proper model structure has been investigated by many authors and it is one of the main sources of uncertainty for a correct evaluation of the outflow hydrograph. In addition, the recent increasing of data availability makes possible to update hydrological models as response of real-time observations. For these reasons, the aim of this work it is to evaluate the effect of different structure of a semi-distributed hydrological model in the assimilation of distributed uncertain discharge observations. The study was applied to the Bacchiglione catchment, located in Italy. The first methodological step was to divide the basin in different sub-basins according to topographic characteristics. Secondly, two different structures of the semi-distributed hydrological model were implemented in order to estimate the outflow hydrograph. Then, synthetic observations of uncertain value of discharge were generated, as a function of the observed and simulated value of flow at the basin outlet, and assimilated in the semi-distributed models using a Kalman Filter. Finally, different spatial patterns of sensors location were assumed to update the model state as response of the uncertain discharge observations. The results of this work pointed out that, overall, the assimilation of uncertain observations can improve the hydrologic model performance. In particular, it was found that the model structure is an important factor, of difficult characterization, since can induce different forecasts in terms of outflow discharge. This study is partly supported by the FP7 EU Project WeSenseIt.

Reservoir Management For Flood And Drought Protection Using Infinite Horizon Model Predictive Control

Model Predictive Control (MPC) is a control method that solves in real time an optimal control problem over a finite horizon. The finiteness of the horizon is both the reason of MPC's success and its main limitation. In operational water resources management, MPC has been in fact successfully employed for controlling systems with a relatively short memory, such as canals, where the horizon length is not an issue. For reservoirs, which have generally a longer memory, MPC applications are presently limited to short term management only. Short term reservoir management can be effectively used to deal with fast process, such as floods, but it is not capable of looking sufficiently ahead to handle long term issues, such as drought. To overcome this limitation, we propose an Infinite Horizon MPC (IH-MPC) solution that is particularly suitable for reservoir management. We propose to structure the input signal by use of orthogonal basis functions, therefore reducing the optimization argument to a finite number of variables, and making the control problem solvable in a reasonable time. We applied this solution for the management of the Manantali Reservoir. Manantali is a yearly reservoir located in Mali, on the Senegal river, affecting water systems of Mali, Senegal, and Mauritania. The long term horizon offered by IH-MPC is necessary to deal with the strongly seasonal climate of the region.

SESAME: Finding Ways Of Promoting SME Adaptation To Flood Risk

Small and medium-sized companies and other enterprises (SMEs) around the world are exposed to flood risk and many of the 4.5 million in the UK are at risk. As SMEs represent almost half of total business turnover in the UK, their protection is a vital part of the drive for greater climate change resilience. However, few have measures in place to ensure the continuity of their activities during a flood and its aftermath. The SESAME project aims to develop tools that encourage businesses to discover ways of becoming more resilient to floods and to appreciate how much better off they will be once they have adapted to the ongoing risk. By taking some of the mystery out of flooding and flood risk, it aims to make it susceptible to the same business acumen that enables the UK’s SMEs to deal with the many other challenges they face. In this paper we will report on the different aspects of the research in the project Understanding behaviour Changing behaviour Modelling impacts Economic impacts Through the above the project will advise government, local authorities and other public bodies on how to improve their responses to floods and will enable them to recommend ways to improve the guidelines provided to SMEs in flood risk areas.

Real-Time Flood Forecasting Systems In Flanders

As a highly urbanized and flood prone region, Flanders has experienced multiple floods causing significant damage in the past. In response to the floods of 1998 and 2002 the Flemish Environment Agency, responsible for managing 1 400 km of unnavigable rivers, started setting up a real time flood forecasting system in 2003. Currently the system covers almost 2 000 km of unnavigable rivers, for which flood forecasts are accessible online (www.waterinfo.be). The forecasting system comprises more than 1 000 hydrologic and 50 hydrodynamic models which are supplied with radar rainfall, rainfall forecasts and on-site observations. Forecasts for the next 2 days are generated hourly, while 10 day forecasts are generated twice a day. Additionally, twice daily simulations based on percentile rainfall forecasts (from EPS predictions) result in uncertainty bands for the latter. Subsequent flood forecasts use the most recent rainfall predictions and observed parameters at any time while uncertainty on the longer-term is taken into account. The flood forecasting system produces high resolution dynamic flood maps and graphs at about 200 river gauges and more than 3 000 forecast points. A customized emergency response system generates phone calls and text messages to a team of hydrologists initiating a pro-active response to prevent upcoming flood damage. The flood forecasting system of the Flemish Environment Agency is constantly evolving and has proven to be an indispensable tool in flood crisis management. This was clearly the case during the November 2010 floods, when the agency issued a press release 2 days in advance allowing water managers, emergency services and civilians to take measures.

Investigating The Sources Of Fresh Water Affecting The Hydrological Balance Of Lakes Enriquillo And Azuei (Hispaniola) – Data Analysis

The Enriquillo and Azuei are saltwater lakes located in a closed water basin in the southwestern region of the island of La Hispaniola, these have been experiencing dramatic changes in total lake-surface area coverage during the period 1980-2012. The size of Lake Enriquillo presented a surface area of approximately 276 km2 in 1984, gradually decreasing to 172 km2 in 1996. The surface area of the lake reached its lowest point in the satellite observation record in 2004, at 165 km2. Then the recent growth of the lake began reaching its 1984 size by 2006. Based on surface area measurement for June and July 2013, Lake Enriquillo has a surface area of ~358 km2. Sumatra sizes at both ends of the record are 116 km2 in 1984 and 134 km2in 2013, an overall 15.8% increase in 30 years. Determining the causes of lake surface area changes is of extreme importance due to its environmental, social, and economic impacts. The overall goal of this study is to quantify the changing water balance in these lakes and their catchment area using satellite and ground observations and a regional atmospheric-hydrologic modeling approach. Data analyses of environmental variables in the region reflect a hydrological unbalance of the lakes due to changing regional hydro-climatic conditions. Historical data show precipitation, land surface temperature and humidity, and sea surface temperature (SST), increasing over region during the past decades. Salinity levels have also been decreasing by more than 30% from previously reported baseline levels. Here we present a summary of the historical data obtained, new sensors deployed in the sourrounding sierras and the lakes, and the integrated modeling exercises. As well as the challenges of gathering, storing, sharing, and analyzing this large volumen of data in a remote location from such a diverse number of sources.

Sources of comparative advantages in Brazil

Based on the Heckscher-Ohlin-Vanek model, this paper investigates relative factor abundance in Brazil, as revealed by its international trade. We study two different time periods: one characterized by high trade barriers (1980 to 1985) and the trade liberalization period (1990 to 1995). Two alternative methodologies are used: the estimation of factor intensity regressions on net exports and the direct computation of factor content in net exports. In the factor intensity regression, we incorporate technological changes that might have occurred over time, and those turned out to be significant. Both methods yield the same results: the Brazilian international trade reveals relative abundance in capital, land and unskilled labor, and scarcity in skilled labor, with qualitatively equivalent results for the two time periods studied.

A robust poverty profile for Brazil using multiple data sources

This paper presents a poverty profile for Brazil, based on three different sources of household data for 1996. We use PPV consumption data to estimate poverty and indigence lines. “Contagem” data is used to allow for an unprecedented refinement of the country’s poverty map. Poverty measures and shares are also presented for a wide range of population subgroups, based on the PNAD 1996, with new adjustments for imputed rents and spatial differences in cost of living. Robustness of the profile is verified with respect to different poverty lines, spatial price deflators, and equivalence scales. Overall poverty incidence ranges from 23% with respect to an indigence line to 45% with respect to a more generous poverty line. More importantly, however, poverty is found to vary significantly across regions and city sizes, with rural areas, small and medium towns and the metropolitan peripheries of the North and Northeast regions being poorest.

Sources of payments practices rigidity

This paper studies the joint determination of the wage payments period between firms and employees. The aggregate timeseries analysis reaches two conclusions: a) the average payments period keep an equilibrium relationship with the previous inflation peak, this indicates some degree of irreversibility of payments practices. b) the low previous inflation peak .;:;_asticity of ave r age payments periods reveal.s a high degree of rigidity of payments practices.The framework developed in the paper incorporates the fol.l.owing sources of payments practices rigidity: a)interactions between optimal. payments period decisions and optimal. number of trips to the bank. b)the occurrence of Pare to inneficiencies in the bargaining process between firms and empl.oyees due to wage regulation. c) integer restrictions on payments frequencies produced by upper bounds on the payments period. The empirical. part of the paper assesses the rel.evance of these different sources of payments practices rigidity using Brazil.ian micro data.

The sources of spinoff equity gains: takeover premiums or operating gains

Although the existence of spinoff equity gains is well documented, their source remains controversial. Arnong many potential causes, the literature suggests that spinoff equity gains could arise from expected tax benefits, expected takeover premia, operating performance improvement or from refocusing benefits. This paper investigates the link between spinoff announcement and post completion equity gains and post spinoff operating performance changes, takeover activity and refocusing benefits. The results indicate that spinoff announcement retums reflect anticipated takeover premiums as well as expected operating performance gains and refocusing benefits unrelated to operating performance. However, only the parent's operating performance gains are anticipated at the spinoff announcement. We find that post spinoff equity gains are driven mostly by operating performance changes for both parents and spun off subsidiaries. Takeover activity and unrelatedness of business lines between parent and subsidiary expIain littIe of post spinoff equity gains. OveralI, the data suggests that spinoffs equity gains mostly reflect anticipated real economic gains in terms of improved operating performance, and to a lesser extent takeover premium and refocusing benefit.

Investigation of flat spectrum radio sources by the interplanetary scintillation method at 111 MHz

Abstract. Interplanetary scintillation observations of 48 of the 55 Augusto et al. (1998) flat spectrum radio sources were carried out at 111 MHz using the interplanetary scintillation method on the Large Phased Array (LPA) in Russia. Due to the large size of the LPA beam (1◦ × 0.5◦) a careful inspection of all possible confusion sources was made using extant large radio surveys: 37 of the 48 sources are not confused. We were able to estimate the scintillating flux densities of 13 sources, getting upper limits for the remaining 35. Gathering more or improving extant VLBI data on these sources might significantly improve our results. This proof-of-concept project tells us that compact (<1 ) flat spectrum radio sources show strong enough scintillations at 111 MHz to establish/constrain their spectra (low-frequency end). Key words. galaxies: general – galaxies: active – galaxies: quasars: general

Ribeira, técnica versus natureza: transformações em prol de um projeto de modernização (1860-1932)

The necessity of the insertion of the capital of Rio Grande do Norte in the world-wide commercial scene and its claim as the seat of political power, in ends of nineteenth and beginning of twentieth century, determined the direction of urban interventions undertaken by government to restructure the city. In that matter, there were several actions of improvements and embellishment in Natal, which had, as a starting point, the adequacy works of the port, located in the Ribeira quarter, with the aim of ending the physical isolation that reinforced its economic stagnation. Besides the problems faced in the opening bar of the Potengi River, and would complement the required improvements, other barriers demonstrate the tension established between the physic-geographic field and the man: the flooded and slope which connected Cidade Alta and Ribeira the first two quarters of the city.The execution of these works demanded knowledge whose domain and application it was for engineering. But, how the actions done for the engineers, in sense to transform natural areas into constructed spaces made possible the intentional conformation of the quarter of the Ribeira in a commercial and politician-administrative center, in the middle of the XIX century and beginning of the XX? Understand, therefore, the employment effects of technology on the physical-geographical Ribeira, is the objective of this work that uses theoretical and methodological procedures of Urban Environmental History, by analyzing the relationship between the environment and the man, mediated by knowledge and use of technologies. The documental research was used, as primary sources, the Messages of the Provincial Assembly Government that later became the Legislative Assembly of Rio Grande do Norte reports and articles on specialized publications, in addition to local newspapers. The work is structured in five chapters. First, some comments about Urban Environmental History (Chapter 1) supplemented with analysis of the conceptual construction of nature in the Contemporary Era and its application in the city (chapter 02), the following chapters (03 and 04) deal with the rise of engineers as a active group in the Brazilian government frameworks and their vision about the nature inside the urban environment and it is studied how the professional technicians dealt with the improvement work of the harbor and in the shock with the natural forces. Other works that would complement this "project" of modernization and had had natural obstacles to be removed the Ribeira flood and slope constitute the subject of the fifth chapter. Finally, some final considerations retake the initial discussions aiming an association between the technique and the nature as junction elements inside the process of constitution of a Modern Natal