Warsaw, Poland
Warsaw, Poland

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Narayan S.,University of Southampton | Nicholls R.J.,University of Southampton | Clarke D.,University of Southampton | Hanson S.,University of Southampton | And 14 more authors.
Coastal Engineering | Year: 2014

Coastal floodplains are complex regions that form the interface between human, physical and natural systems. This paper describes the development, application and evaluation of a conceptual foundation for quantitative integrated floodplain risk assessments using the recently-developed SPR systems model. The SPR systems model is a conceptual model that combines the well-established Source-Pathway-Receptor (SPR) approach with the concept of system diagrams. In comparison to the conventional approach, the systems model provides spatially explicit quasi-2D descriptions of the floodplain in terms of constituent elements and possible element linkages. The quasi-2D SPR, as it will henceforth be referred to in this paper, is not the final product of this work, but is an important intermediate stage which has been pursued as part of a wider European flood risk project THESEUS (www.theseusproject.eu). Further research is currently on-going to provide full quantification of the quasi-2D SPR, and to add further refinements such that hydraulic assessments could follow on easily and rapidly from the results of these appraisals.The first part of the paper synthesises current conceptual treatment of coastal floodplains and identifies areas for improvement in describing coastal floodplains as complex systems. The synthesis demonstrates that the conceptual foundation of a 'typical' flood risk study often achieves a less comprehensive and integrated description of the floodplain than the quantitative models which it informs. From this synthesis, the quasi-2D SPR is identified as a more robust and informative conceptual foundation for an integrated risk assessment. The quasi-2D SPR has been applied to seven European coastal floodplains as part of the THESEUS project. The second part of the paper discusses in detail the application of the quasi-2D SPR to three contrasting floodplain systems - an estuary, a coastal peninsula and a mixed open coast/estuary site. The quasi-2D SPR provides a consistent approach for achieving comprehensive floodplain descriptions that are individual to each coastal floodplain. These are obtained through a robust, participatory model-building exercise, that facilitates developing a shared understanding of the system. The constructed model is a powerful tool for structuring and integrating existing knowledge across multiple disciplines. Applications of the quasi-2D SPR provide key insights into the characteristics of complex coastal floodplains - insights that will inform the quantification process. Finally, the paper briefly describes the on-going quantitative extension to the quasi-2D SPR. © 2013 Elsevier B.V.


Andersen J.H.,DHI | Axe P.,SMHI | Backer H.,HELCOM | Carstensen J.,National Environmental Research Institute of Denmark | And 15 more authors.
Biogeochemistry | Year: 2011

The eutrophication status of the entire Baltic Sea is classified using a multi-metric indicator-based assessment tool. A total of 189 areas are assessed using indicators where information on reference conditions (RefCon), and acceptable deviation (AcDev) from reference condition could be combined with national monitoring data from the period 2001-2006. Most areas (176) are classified as 'affected by eutrophication' and only two open water areas and 11 coastal areas are classified as 'unaffected by eutrophication'. The classification is made by application of the recently developed HELCOM Eutrophication Assessment Tool (HEAT), which is described in this paper. The use of harmonized assessment principles and the HEAT tool allows for direct comparisons between different parts of the Baltic Sea despite variations in monitoring activities. The impaired status of 176 areas is directly related to nutrient enrichment and elevated loads from upstream catchments. Baltic Sea States have implemented nutrient management strategies since years which have reduced nutrient inputs. However, eutrophication is still a major problem for large parts of the Baltic Sea. The 2007 Baltic Sea Action Plan is projected to further reduce nutrient inputs aiming for a Baltic Sea unaffected by eutrophication by 2021. © 2010 The Author(s).


The atmospheric low is the relatively durable structure. He keeps his spiral arms almost like solid body. This allows to model this structure as the settled movement. The rotated durable structure are connected with the fact that the kinematics of the core in the depression is characterizes the linear dependence of the orbital speed from the distance from his center. The well well-known gradient wind balance is the model of the vortex but generalized by the addition component of radial movement arise from resistances of the movement.


The maximum absolute is the greatest observation of finite size sample. This subtracted quantity is not a constant value. The next value of the absolute extreme, if it occurs, may belongs to the general population of the current climate or to herald the climate change. Notion of absolute maximum has been interpreted as last order statistics for a sample. It was showed how the empirical probability distribution changed with increased N - year maximum definition of trial sample. The Type III maximum value distribution was used to illustrate the asymptotic approaching of greatest measured values to upper bound of meteorological element. An important element of climate is the maximum rainfall causing flooding and floods. The properties of order statistics and asymptotic properties for the daily rainfall at the point and spatial layout was presented.


The aim of the study is to highlight the role which the a priori probability of the climatic phenomenon (and thus its frequency of occurrence) can play in the scheme of alternative forecasts. In the synoptic forecast practice prior probabilities are not taken explicitly into account. They manifest themselves in the form of generał climatological knowledge, but they are more subjective, resulting from experience. So-calied Bayesian approach allows to optimize the decision situation on the base of forecasts. However, to satisfy the condition of minimum average risk both: cost of the decision and, as well, prior probabilities have to be known. An alternative prediction scheme without priors is possible in practice, but it is not optimal in the sense of minimizing the average risk. Additionally the attention should be paid to the possibility of climate change which can be expressed by the variability of climate priors.


The study by Eugeniusz Romer presented here is based on materials from the years 1871-1890. It was first published in 1910 in Switzerland in French and was recited by climatologists with great interest. In Polish, it was first published in 1912 in Polish Encyclopedia (Encyklopedia Polska), titled The Climate of Polish Lands (Klimat ziem polskich). The study, which was central to Polish climatology, identified Polish climate zones and also proved the existence of Polish climate. The climate zones were defined on the basis of air temperature, and especially isotherms reduced to sea level. In his paper, Romer refutes the thesis that Polish climate is an intermediate one between the oceanic west and the continental east of Europe. The existence of the Polish climate was confirmed by de Martonne, one of the most outstanding French geographers. He included this climate type in the overall classification of the Earth's climate varieties and found its counterparts in the borderland between US and Canada, as well in Siberia, in the southern part of Outer Manchuria.


Koziel S.R.,IMGW
Przeglad Geofizyczny | Year: 2010

The term "mathematicity of climate " refers to the idea of mathematical aspect of nature, being in the centre of the interest both mathematics itself, philosophy and the methodology of the science. Analysis of the semantic question why nature, in this climate, is a mathematical must lead to the conclusion that in both cases it is a metaphysical overtones. However mathematicity of the climate is the problem of the applicability of mathematical methods themselves. According to the common definition climate is an invariant measure on the attractor. It is a strange attractor, whose dynamics is chaotic and the system is not predictable. This is the property of the physics of the climate, because atraktor himself is the mathematical notion. We are only just able to examine the properties of equations, with a conviction that they are sufficiently close approximation of the actual model, the infinite phase space. The task of modeling both the weather and the climate becomes almost metaphysical. Not enough this, we are in the fractal space equations of models assume the real numbers without possibility of correct initial conditions. And these are not available, not only in the act of measurement but also in the process of computing. Elementary fact in the climate system is an event - the occurrence of the phenomenon: a meteor or hydrometeor. If, however, meteorology and hydrology deal with the physics of the phenomena it describes the climatology rather their repeatability. In practice, studies climatological events in the environment are called random, but they cannot identify. In fact, they are always events in the physical sense, and would require the establishment some probability measure on attractor. One such probabilistic measure can not a priori however know. The interpretation can have the exclusively descriptive character: exactly n the event stepped out in the period of instrumental measurements times.


Chosen dynamic linear Bayesian models and their application to simulation of river flow hydrograph are described in this paper. Assuming that the discharge is observed in regular time steps and the measurement error rests the same for each observation, one can predict the next state of the system using Bayesian model for a new observation. For this goal two dynamic linear Bayesian models were applied: Matrix Normal Regression and Multivariate Discount Weighted Regression. Both of them were combined and implemented into Two Level Bayesian Model at the Hydrological Centre in the Institute of Meteorology and Water Management in Poland. The details of model's algorithms are presented as well as simulation of annual flow hydrograph at Wizna on the Narew river in 1996. The comparison of modelled and observed hydrographs were performed by means of graphical and statistical measures. Larger stability and better accuracy are obtained for Multivariate Discount Weighted Model. Future research will be focused on testing the influence of changes in the variance matrix on model assessment and on application of vector modelled variable.


Koziel S.R.,IMGW
Przeglad Geofizyczny | Year: 2010

It is possible to treat weather forecast uncertainty as uncertainty of measurements. The hydrometeorological measurement is made by the definite device with known accuracy of the measurement. In hydro-meteorological practice the measurement is a single, unique action. It is not possible to repeat the measurement, because it would be made in different state of the environment. Every method of weather forecast may be considered as a result of some kind of measurement of the future system state - weather. Hence, every method of forecast may be treated as a kind of an indirect measurement device. In practice, when results of different models are available, some problems appear - how to interpret jointly their results. It is shown that for many simultaneous forecasts the applied procedure can be analogous to the procedure used when physical measurements consist of several values, like in a statistical sample. In practice forecast accuracy of every model is defined as a variance of forecasts error. So, the situation is analogous to the problem of "constant value" estimation, known in the BLUE theory. When individual forecasts are correlated the weighed averaging method can also be applied, as well as when it is attributed to subjective weight of individual forecasts.

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