Wyniki wyszukiwania - BazTech

1

The kinematic and thermodynamic environment during cloud-to-ground lightning occurrence in Poland

Sulik Sławomir, Taszarek Mateusz

Meteorology Hydrology and Water Management. Research and Operational Applications

|

2024

|

Vol. 12, Iss. 1

83--103

EN

This study identifies convective and kinematic parameters that positively influence elevated values of cloud-to-ground lightning flashes (CGs) in Poland. The analysis used data from the PERUN lightning detection and location system from IMGW-PIB and reanalyses of the ERA5 model from ECMWF for the period 2002-2020. In addition, a spatial-temporal distribution analysis was carried out for the period 1940-2022, covering the key parameters necessary for the appearance of convection. Results showed that thunderstorms most often occur in the summer, but also that there are increasingly favorable conditions for the appearance of organized multicellular systems in the spring. CG flashes most often form in a most-unstable convective available potential energy (MU CAPE) environment of about 1300 J/kg along with vertical wind shear (0-6 km AGL bulk wind shear) of 13-14 m/s. Using the WMAXSHEAR parameter, it was possible to conclude that overlapping CAPE and DLS values of about 500 m2/s2 imply increased electrical activity. At the same time, a high correlation with the Hail Size Index (HSI) parameter implies a positive relationship between the occurrence of hailstorms and an increased number of CGs generated in the case of supercells. The research also found a gradual increase in air temperature, MU CAPE, MU Mixing Ratio and the MU WMAXSHEAR parameter for the area under study.

2

The nonlinear effects in the ionospheric plasma generated by strong thunderstorms seen by DEMETER satellite

Błęcki J., Wronowski R., Jujeczko P.

Archives of Mechanics

|

2024

|

Vol. 76, nr 3

277--290

EN

The terrestrial ionosphere is mainly a plasma region which is very sensitive to different disturbances. A wide range of plasma instabilities can develop in this region, which are often nonlinear processes and leading to the development of plasma turbulence. Turbulence plays a crucial role in the dynamics of the space plasma processes. The turbulence appears when some physical parameter exceeds a certain level. It can have place during strong thunderstorms. The ionosphere is sometimes treated as plasma physics laboratory with unique possibility to study fundamental plasma processes. The use of ionospheric satellite gives the chance to perform insitu measurements of plasma parameters during dynamic processes. For our analysis we used a set of selected data of the electric and magnetic fields variations in ELF (Extra Low Frequency 10–1250 Hz) and VLF (Very Low Frequency 100–20000 Hz) ranges originated from the French microsatellite DEMETER which was operating on the circular orbit with inclination of about 80◦ at altitude of 660km from July 2004 until December 2010. The Fourier, wavelet and bispectral analyses of these signals are given in this paper. Three wave processes have been identified during few very strong strokes. In some cases the nonlinear interactions of whistlers with the VLF signals of ground based transmitters have been registered. The character of spectra suggests the presence of Richardson’s cascade. Our conclusion is that in few cases these results are related to whistler turbulence.

3

Study of the lightning activity over Poland for different solar activity

Błęcki Jan, Iwański Rafał, Wronowski Roman, Jujeczko Paweł

Artificial Satellites : Journal of Planetary Geodesy

|

2022

|

Vol. 57, No. 4

194--209

EN

The question of the connection between solar and thunderstorm activity is not new. The discussion among scientists began before the cosmic era. The correlations of the ground-based registration of the cosmic ray flux and meteorological observations have been performed since the 50s of the 20th century. The discussed problem is related to the influence of cosmic rays on the creation of clouds, particularly thunderstorm clouds. The intensity of the galactic cosmic ray flux is controlled by the density and velocity of the solar wind. The increase in the solar wind flux during high solar activity leads to decreasing galactic cosmic ray flux, but on the other hand, the solar activity creates solar cosmic rays. Using data from the PERUN system and the DEMETER satellite, we tried to estimate the connection between the thunderstorm activity in Poland and solar activity during the period of the DEMETER operational activity (2004-2010). The influence of thunderstorms on the ionosphere and its dependence on solar activity is also discussed. However, due to the short time interval of the available data covering an insignificant part of the solar cycle, close to the minimum activity, our findings are not fully conclusive. No correlation was found between the cosmic ray flux and lightning activity given by the number of the discharges. However, some of the most energetic lightning discharges in the analyzed period occurred close to the minimum of the solar activity and their appearance is discussed.

4

Number of days with thunderstorm in the area of Bydgoszcz in the years 1971-2010 using the example of the Bydgoszcz-Airport weather station

Łaszyca Edward Zbigniew

Geography and Tourism

|

2021

|

Vol. 9, No. 2

67--74

EN

The paper analyses the occurrence of thunderstorms in Bydgoszcz in the multi-annual period 1971–2010 based on data from the Bydgoszcz-Airport weather station – ref. EPBY according to ICAO (International Civil Aviation Organization). The article examines variations in monthly, seasonal and annual mean values of weather elements. The calculation pertaining to selected elements of descriptive statistics involved regression analysis. Based on the linear function the author determines the direction and trends of changes of the analysed elements in time. Analysis of this data leads to the conclusion that the number of thunderstorms in the examined forty-year period declined, but also a decrease in the frequency of this phenomenon was observed in Bydgoszcz. The highest number of storms in the examined multi-year period in the whole year (29) and in the warm half-year (28) was recorded in 1973 and in 1997, and the lowest in 2003 (only 6). The studies indicate a significant downward trend in the number of storms occurring in the multi-annual period 1971-2010.

5

Comparative study of the energetic electrons registered together with the broad band emissions in different regions of the ionosphere

Błęcki Jan, Wronowski Roman, Słomiński Jan, Savin Sergey, Iwański Rafał, Haagmans Roger

Artificial Satellites : Journal of Planetary Geodesy

|

2020

|

Vol. 55, No. 4

130--149

EN

ELF/VLF waves have been registered in the outer polar cusps simultaneously with high energy electrons fluxes by the satellites Magion 4 (subsatellite to Interball 1), Polar and CLUSTER. Further, we discuss similar observations in the different regions of the ionosphere, where DEMETER registered energetic electrons. The DEMETER satellite operating on the nearly polar orbit at the altitude 650 km crossed different regions in the ionosphere. Registrations of ELF/VLF/HF waves together with the energetic electrons in the polar cusp, in the ionospheric trough and over thunderstorm areas are presented in this paper. The three satellites of ESA’s Swarm mission provide additional information on the ELF waves in the mentioned areas together with electron density and temperature. A brief discussion of the generation of these emissions by the so-called “fan instability” (FI) and beam instability is presented.

6

Proposed classification for all types of wind storms in Poland

Chmielewski T., Nowak H.

Archives of Civil Engineering

|

2020

|

Vol. 66, nr 4

183--200

EN

International scales describing the intensity of tornadoes are investigated along with reports from the Polish Government Security Centre on all types of wind storms in Poland. Then, collected tornado reports for the years 1899-2019 in Poland, a set of the annual maximum gust wind speeds measured at 39 meteorological stations from 1971 to 2005 (35 years), descriptions of Poland’s strongest wind storms in the 21st century, estimating the risk of significant strong and extreme winds in Poland, and classification of maximum wind speeds by Lorenc (2012) are presented. Based on these data, i.e. measured and estimated wind speeds, this paper proposes two separate intensity scales to categorize synoptic, thunderstorm, and downslope winds (in the Tatra and Karkonosze regions), derechos, tornadoes, and downbursts, i.e. all types of wind storms. These scales are simpler than the one put forward by Lorenc (2012). These two scales cover a range of maximum wind speeds from 20 to 90 m/s. This proposal is only applicable to Poland. Other countries may determine whether it applies to them.

PL

Różnego rodzaju burze wiatrowe w Polsce każdego roku stanowią potencjalne duże zagrożenie strat finansowych w gospodarce, zdrowia i życia ludzkiego w naszym kraju. W niniejszym artykule przedstawiono: raport Rządowego Centrum Bezpieczeństwa (RCB) o potencjalnych zagrożeniach naturalnych w Polsce, międzynarodowe skale opisujące intensywność trąb powietrznych, badania dotyczące liczności trąb powietrznych w latach 1899-2019 w Polsce, zestaw rocznych maksymalnych prędkości wiatru w porywach mierzonych na 39 stacjach meteorologicznych w latach 1971-2005 (35 lat), opisy najsilniejszych burz wiatrowych w Polsce w XXI wieku, oszacowanie ryzyka silnych i ekstremalnych wiatrów w Polsce i klasyfikację maksymalnych prędkości wiatru w Polsce i skutki ich działania, zaproponowaną w 2012 roku przez Lorenc [10]. Na podstawie powyższych danych zaproponowano dwie osobne skale klasyfikacji maksymalnych prędkości wiatru i skutki ich działania dla wszystkich burz wiatrowych, tj.: synoptycznych burz wiatrowych, burz wiatrowych lokalnych, burz w rejonach górskich (wiatru halnego w rejonie Tatr lub fenu w rejonie Karkonoszy), trąb powietrznych, szkwałów i rozległych burz wiatrowych typu derecho. Te dwie skale obejmują zakres maksymalnych prędkości wiatru od 20 do 90 m/s.

7

Long term analysis of thunderstorm related parameters over Visakhapatnam and Machilipatnam, India

Umakanth N., Satyanarayana G. Ch., Simon B., Rao M. C., Babu N. Ranga

Acta Geophysica

|

2020

|

Vol. 68, no. 3

921--932

EN

In this present work, an attempt has been made to analyze various thunderstorm-related parameters and their infuence over the two stations Visakhapatnam (VSK) and Machilipatnam (MTM). The thunderstorm-related parameters used in the present study are convective available potential energy (CAPE), lifted index, K-index, total totals index (TTI), humidity index, convective inhibition, thunderstorm prediction index (TPI), deep convective index (DCI) and updraft vertical velocity. This analysis was carried out using NCEP NCAR reanalysis monthly data for the time period from 1948 to 2012. These parameters have given good guidance for studying the thunderstorm event. We also analyzed IMD thunderstorm occurrence days reported at two stations, i.e., VSK and MTM with NCEP NCAR (daily data) calculated CAPE, TTI, TPI and DCI parameter threshold days in pre-monsoon season for every year during the time period 2010 to 2019. Out of those four parameters, TTI has shown good correlation with the IMD recorded days. So we have attempted the prediction of thunderstorms using artifcial neural network (ANN) and auto-regressive moving average (ARMA) techniques for TTI parameter. While using these techniques, we have experimented in three training sets, i.e., 90%, 80% and 70%. Another attempt has been made to assess the skill of ARMA and ANN techniques in forecasting the occurrence of thunderstorm activity at VSK and MTM stations. The present study suggests that ANN has high skill than ARMA. From this study, we can understand that VSK has more chances for thunderstorms than MTM.

8

The time and power spectrum density analysis of different lightning components based on electric field waveforms from 2014 thunderstorm season recorded in the south-eastern part of Poland

Karnas G., Barański P., Masłowski G., Sobolewski K.

Przegląd Elektrotechniczny

|

2016

|

R. 92, nr 2

144--147

EN

This paper is focused on the Power Spectrum Density analysis of the lightning electric field signatures collected in Subcarpathian part of Poland, in 2014. Lightning records were carried out in two different ways. The slow electric field sensor (TLF-ELF), the mill, was used for observation of lightning activity during entire thunderstorm lifetime. The second recording mode was the acquisition of fast electric field changes (0.3 Hz to 3 MHz) associated with different types of cloud-to-ground (CG) and inter-, intra-cloud (IC) type discharges. The registration process was synchronized with microsecond time precision. This allowed to relate lightning stroke detections to these reported by the LINET, the commercial lightning location system. Different lightning stroke components, as e.g. the preliminary breakdown (PB), the return stroke (RS) and the continuing current (CC) were identified with application of the Short-Time Fourier Transform. The spectral analysis might be adapted to improve in future some detection algorithms used in lightning location systems. Such lightning CG stroke discrimination is not applied as yet by any lightning location system routinely operated in Europe.

PL

W artykule skupiono się na analizie spektrogramów widmowej gęstości mocy wyznaczonych dla różnych przebiegów piorunowego pola elektrycznego zebranych w południowo-wschodniej części Polski w 2014 roku. Dane zostały zebrane z wykorzystaniem dwóch sensorów pola elektrycznego. Sensor pola elektrycznego pracujący w zakresie TLF-ELF umożliwił obserwację aktywności burzowej w długofalowym okresie czasu. Drugi typ rejestracji obejmował akwizycję szybkich zmian pola elektrycznego (0.3 Hz do 3 MHz) pochodzących of różnych typów wyładowań doziemnych oraz wewnątrz-, między-chmurowych. Proces rejestracji został zsynchronizowany z mikrosekundową precyzją. Pozwoliło to na porównanie własnych rejestracji z detekcjami LINET-u – komercyjnego systemu lokalizacji wyładowań. Różne składowe wyładowania takie jak wyładowania wstępne, udar główny oraz prąd długotrwały zostały zidentyfikowane z wykorzystaniem krótkoczasowej transformaty Fouriera. Analiza spektralna może w przyszłości zostać wykorzystana w usprawnieniu algorytmów detekcji wyładowań. Taki rodzaj identyfikacji wyładowań doziemnych nie został jak dotąd zaimplementowany w żadnym systemie lokalizacji wyładowań atmosferycznych pracującym regularnie w obszarze Europy.

9

Lightning Induced Ventricular Fibrillation risk during wandering

Wiater J.

Przegląd Elektrotechniczny

|

2016

|

R. 92, nr 2

106--111

EN

Wandering is a popular way of spending leisure time especially for the urban population. Health problems arising from such outdoor recreational activities are better understood today and may improve survival in case of accidents if sufficient awareness of clinical staff is established. The purpose of this paper is to shed light on this physiological phenomenon by investigating the connection between the physics associated with lightning strikes and the physiological response of the human body. From the results a minimum safety-distance from different trees species is derived. Flat rooted trees are more dangerous than tap rooted trees. In the worst case it may be considered safe if a distance of at least 25 meters to tree trunks is maintained.

PL

Turystyka piesza jest popularnym sposobem spędzania wolnego czasu, szczególnie dla mieszkańców miast. Problemy zdrowotne wynikające z tej aktywności są dobrze poznane, ale w szczególnych przypadkach wiedza o zagrożeniu może być pomocna i może się przyczynić do zwiększenia szans na przeżycie. Celem tej publikacji jest pokazanie związku pomiędzy wyładowaniem piorunowym a reakcją organizmu ludzkiego. Na podstawie otrzymanych wyników wyznaczono bezpieczny odstęp od drzew podczas wyładowań piorunowych. Drzewa z systemem poziomym systemem korzeniowym stwarzają większe zagrożenie niż drzewa z systemem palowym. W najgorszym przypadku bezpieczny odstęp od pnia drzewa wynosić powinien co najmniej 25 metrów.

10

Convective and non-convective wind gusts in Poland, 2001-2015

Kolendowicz L., Taszarek M., Czernecki B.

Meteorology Hydrology and Water Management. Research and Operational Applications

|

2016

|

Vol. 4, iss. 2

15--21

EN

The main aim of the article is to present the climatology of the peak wind gust frequency in Poland caused by the impact of both atmospheric circulation and the presence of thunderstorm clouds. Nine meteorological stations for the measurement period of 2001-2015 were taken into account. Only SYNOP reports with a peak wind gust higher or equal to 15 m s-1 in thunderstorm and non-thunderstorm days are considered in this study. The results indicate that the highest threat in terms of frequency and strength of peak wind gusts due to convection occurs in July. In winter, thunderstorms are rare, but if they occur, about 80% of them produce wind gusts exceeding a threshold of 15 m s-1. Peak wind gusts in a non-thunderstorm days are the highest and the most frequent in January, and are at a minimum during summer. Comparing both types, peak wind gusts during days with a thunderstorm were on average stronger than those without an involved convection. This indicated that convection was an important factor in enhancing the strength of a wind gust. The highest value in our base was 34 m s-1, recorded in Kraków on 8th July 2015 within the occurrence of a severe thunderstorm, while the highest value in a day without a thunderstorm was 33 m s-1, recorded in Łódź on 31st January 2002.

11

Burze w Hornsundzie (SW Spitsbergen)

Soroka J., Bania M.

Problemy Klimatologii Polarnej

|

2013

|

Nr 23

137--146

PL

W pracy opisano przypadki burz zanotowane w Polskiej Stacji Polarnej w Hornsundzie w latach 1983-2012. W tym okresie zaobserwowano zaledwie siedem dni z burzą. Z każdym zaobserwowanym zjawiskiem wyładowań atmosferycznych powiązano przebieg wybranych elementów meteorologicznych oraz sytuację synoptyczną i typ cyrkulacji. Burze w Hornsundzie obserwowano jako epizody z co najwyżej kilkoma wyładowaniami atmosferycznymi. Zjawiska te związane były zazwyczaj z aktywnymi frontami chłodnymi napływającymi z południa i południowego-zachodu. Uzupełnieniem opisu burz są relacje osób, które przeżyły burze na Spitsbergenie.

EN

The thunderstorms are very rare phenomena in polar regions. This paper present an analysis of occurrence of atmosphere lightning observed at Polish Polar Station Hornsund (Spitsbergen) over the last 30 years (1983-2012). During this period only seven thunderstorms occurred (20 December 1984, 5 March 1985, 9 September 1985, 26 March 1990, 24 November 1993, 5 and 8 August 1997). For each cases a course of meteorological parameters, synoptic situations and type of circulation were described. Thunderstorms at Hornsund are in most cases a short event with a few lightning. This phenomena were usually caused by strong cold front, which comes from south and southwest.

12

Pioruny - nie do końca wyjaśniona zagadka

Hemka L.

Nowa Elektrotechnika

|

2007

|

nr 9 (37)

20--22

13

Personal behaviour during thunderstorms

Polo S.

Przegląd Elektrotechniczny

|

2000

|

nr 7-8

207-209