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1

Simplified model for calculation of clutters caused by wind turbines

Dziewit Z., Bucki B.

Meteorology Hydrology and Water Management. Research and Operational Applications

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2017

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Vol. 5, Iss. 2

3--12

EN

metallic parts. Based on the assumption that only moving, metallic parts of a turbine cause echoes indelible by standard filtering used in radar signal preprocessing, a method of preliminary evaluation of such maximum potential clutters was developed. The method takes into account how great a part of a turbine is really illuminated by a radar beam and for this part calculates a RCS (Radar Cross Section) and its equivalent radar reflectivity. A very detailed description of the model is given in this article in order for it to be easy to implement in any calculation system. Discussion of the influence of the main simplifications assumed in this model, as well as a comparison of the theoretical results with example data in operational mode of radar work, are included in this article.

2

Porównanie danych opadowych z sieci deszczomierzy i radaru meteorologicznego dla Wrocławia

Siekanowicz-Grochowina K., Licznar P., Konieczny T., Zaleski J.

Gaz, Woda i Technika Sanitarna

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2017

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Nr 7

303--307

PL

W pracy dokonano porównania danych opadowych zarejestrowanych za pomocą deszczomierzy, należących do Miejskiego Przedsiębiorstwa Wodociągów i Kanalizacji S. A. we Wrocławiu oraz przy użyciu radaru meteorologicznego zlokalizowanego w Pastwniku (województwo dolnośląskie), urządzenia działającego w sieci POLRAD Instytutu Meteorologii i Gospodarki Wodnej. Analizie poddano szeregi opadowe z letniego półrocza 2014 roku. Zidentyfikowano współrzędne komórek siatki zobrazowania radarowego, które odpowiadają lokalizacji deszczomierzy MPWiK we Wrocławiu. Na tej podstawie wydzielono 10-cio minutowe szeregi czasowe zarejestrowanych odbiciowości radarowych, które zostały transponowane w docelowe szeregi natężeń opadów na podstawie przyjętej zależności Z-R. Szeregi wartości natężeń opadów według radaru zostały porównane z odpowiadającymi im szeregami wartości natężeń opadów zarejestrowanych za pomocą deszczomierzy. Kolejno, poddano ocenie korelację danych o natężeniach opadów z sieci deszczomierzy i przeliczonych na podstawie odbiciowości zarejestrowanej przez radar. W podsumowaniu zawarto identyfikację czynników wpływających na badaną korelację danych opadowych z analizowanych źródeł dla Wrocławia.

EN

In this article the comparison between precipitation data obtained from rain-gauge network belonging to MPWiK S.A. in Wrocław and from meteorological radar located in Pastewnik (Lower Silesia, Poland) – device working in POLRAD system, property of Institute of Meteorology and Water Management was performed. Precipitation time series for summer half-year 2014 were analysed. The cell coordinates from radar grid corresponded to MPWiK’s rain-gauges localization were identified. 10minutes time series of registered radar reflectivity were transposed to rainfall intensity using Z-R relationship. Time series of rain intensity from rain-gauges network and radar were compared. The correlation between precipitation intensity data from two sources, rain-gauges network and radar, was evaluated In the summery, the identification of factors influenced on correlation between precipitation data for Wrocław obtained from rain-gauges network and radar was conduct.

3

MeteoGIS: GIS-based system for monitoring of severe meteorological phenomena

Jurczyk A., Ośródka K., Szturc J., Giszterowicz M., Przeniczny P., Tkocz G.

Meteorology Hydrology and Water Management. Research and Operational Applications

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2015

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Vol. 3, Iss. 2

49--61

EN

The MeteoGIS system developed at the Institute of Meteorology and Water Management – National Research Institute in Poland is a GIS-based system for real-time monitoring of weather and the generation of meteorological warnings. Apart from its monitoring features, it can also provide more advanced analysis, including SQL (Structured Query Language) queries and statistical analyses. Input data are provided mainly by the INCA-PL 2 nowcasting model which employs forecasts from the high-resolution AROME numerical weather prediction model and measurement data from the Polish weather radar network POLRAD and surface meteorological stations. As well as this, data from the PERUN lighting detection system are used. Ingestion of such data allows for the mitigation of risk from potentially hazardous weather phenomena such as extreme temperatures, strong wind, thunderstorms, heavy rain and subsequent impending floods. The following meteorological parameters at ground level are visualised in the MeteoGIS: (i) precipitation (accumulation and type), (ii) temperature, (iii) wind (speed and direction), (iv) lightning (locations and type). End users of the system are workers from civil protection services who are interested in shortterm warnings against severe weather events, especially area-oriented ones (related to districts, catchments, etc.). The reliability of visualised data is a very important issue, and from the MeteoGIS user’s point of view the improvement in data quality is a continuous process.

4

Radarowa detekcja superkomórek burzowych w Polsce

Pilorz W.

Teledetekcja Środowiska

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2014

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T. 51

93--105

EN

“Supercell storms are capable of producing the most violent of hail, wind and tornado events (Moller et. al. 1994); thus they are the most important storm type to forecast and detect” (Moller 2001). Supercell storm is defined by “presence of a deep and persistent, rotating updraft called a mesocyclone” (Weisman and Klemp 1984). Mesocyclone presence leads to the specific vertical storm structure seen as a Bounded Weak Echo Region. Mesocyclone presence also leads to the changes in the horizontal shape of the storm, observed on the radar reflecivity in a low elevation as a hook echo. Large hail, associated with supercells, is a very important threat to detect. It can be easily recognized by the presence of the reflecivity more than 50 dBZ, above 8 km above ground level (Burgess and Lemon 1990). Nine cases of supercells in Poland between 2007 and 2013 were examined. Results show that all quoted features were present. Moreover, most of them appeared before the threat which they indicate. It means that threats associated with supercells can be predicted in a short time.

5

Asymilacja trójwymiarowej odbiciowości radarowej do numerycznego modelu meteorologicznego metodą zespołowego filtru Kalmana : metodyka i eksperyment

Szturc J., Jakubiak J., Jurczyk A., Ośródka K.

Przegląd Geofizyczny

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2014

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Z. 1-2

19--38

EN

Assimilation of 3d weather radar reflectivity to nwp model using ensemble Kalman filtering: methodology and experiment

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Experiments with three-dimensional radar reflectivity data assimilation into the COAMPS model

Jakubiak B., Szturc J., Ośródka K., Jurczyk A.

Meteorology Hydrology and Water Management. Research and Operational Applications

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2014

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Vol. 2, Iss. 1

43--54

EN

High temporal and spatial resolution of radar measurements enables to continuously observe dynamically evolving meteorological phenomena. Three-dimensional (3D) weather radar reflectivity data assimilated into the numerical weather prediction model has the potential to improve initial description of the atmospheric model state. The paper is concentrated on the development of radar reflectivity assimilation technique into COAMPS mesoscale model using an Ensemble Kalman Filter (EnKF) type assimilation schemes available in Data Assimilation Research Testbed (DART) programming environment. Before weather radar data enter into the assimilation system, the measurement errors are eliminated through quality control procedures. At first artifacts associated with non-meteorological errors are removed using the algorithms based on analysis of reflectivity field pattern. Then procedures for correction of the reflectivity data are employed, especially due to radar beam blockage and attenuation in rain. Each of the correction algorithms is connected with generation of the data quality characteristic expressed quantitatively by so called quality index (QI). In order to avoid transformation of data uncertainty into assimilation scheme only the radar gates successfully verified by means of the quality algorithms were employed in the assimilation. The proposed methodology has been applied to simulate selected intense precipitation events in Poland in May and August 2010.