Dangerous Meteorological Phenomena Research Articles

Regional features of glaze ice events frequency in the north of the European territory of Russia in the current changing climate

Recently, the interest in society in observing and forecasting dangerous meteorological phenomena in the cold period of the year has noticeably grown. In this work, we study the phenomenon of glaze ice in the north of the European territory of Russia in the North-Western Federal District. Here glaze ice (icing) is less frequent than other forms of ice accretion, but its characteristics most often exceed the criteria of dangerous meteorological phenomena. It is a great danger for various areas of the economy, ship navigation, causing an increase in traumatism of the population and damage to infrastructure. In accordance with the aim of the work, the spatial and temporal variability of the frequency of glaze ice accretion on the territory of the North-Western Federal District in the period 1986–2022 is investigated. The results are obtained on the basis of instrumental observations of meteorological stations. Using statistical analysis, the features of mean yearly frequency at each meteorological station were studied. To assess the direction of annual changes in the glaze ice frequency, the linear trend coefficient was calculated for each meteorological station. The least squares method was used for this purpose. It is shown that the maximum number of days with glaze ice occurs in the central part of the North-Western Federal District. This can be attributed to the more frequent movement of Atlantic and southern cyclones to high latitudes and their precipitation, especially at the atmospheric fronts and in the warm sectors of the cyclones, at air temperatures near zero and below. What makes the spatial distribution of glaze ice frequency even more uneven is the presence of uplands in the European territory of Russia. More precipitation falls on their windward slopes, and the temperature decreases with altitude. The findings show that in recent decades there has been an increase in the frequency of the glaze ice phenomenon in the region. At the same time, the interannual variability remains relatively constant. Taking into account the positive trend in the number of glaze ice events and increasing air temperature and precipitation, it is necessary to develop measures to deal with this hazardous phenomenon and minimize damage from it.

Short Blizzard Episode in the Northeastern Part of Romania, in the Second Decade of November 2023

Abstract Severe weather phenomena are those meteorological phenomena that can temporarily become dangerous for the population, by threatening its safety or can cause material damage in a certain area. In order for the authorities and the population to be notified in time, meteorological warnings are issued. Therefore, issuing a warning will be taken into account according to the degree of severity of the forecasted meteorological phenomenon and will take into account its extent, how it will evolve and the degree of vulnerability of the regions to be affected. For this purpose, warning thresholds have been established for certain meteorological phenomena that can become dangerous, and based on this, color codes have been established, which gradually show the dangerousness of the phenomena that are about to occur. In the cold season, the blizzard is part of the category of dangerous meteorological phenomena, even more so when they are early or late, in the months of November or April. If the late ones are more frequent, (in the last 10 years there were 2 blizzard events, in 2017 and 2023), the early ones have an even lower frequency, and sometimes it can be a derivative of this phenomenon, because they are not met all the blizzard conditions. This study analyzes a phenomenon that took place in the second decade of November 2023 in the region of Moldova and which was associated with the blizzard phenomenon.

Decision criteria for the classification of meteorological phenomena in the weather radar complex of the near-airfield zone

The increasing need to obtain data on the meteorological situation to ensure the safety of aircraft flight actualizes the development of radar systems for remote collection and processing of information, including for solving the problems of classifying dangerous weather phenomena. This determined the primary development of the domestic weather radar complex of the near airfield zone (WR BZ). The article presents the features of the construction of the WR BZ, as well as the main tasks it solves. To classify meteorological phenomena from cloudiness to squall in the weather radar complex of the near airfield zone, it is proposed to take as a basis the criteria tested by weather radar stations of previous generations. These criteria are based on an analysis of the height distribution of reflectivity, taking into account the vertical temperature profile. In addition, a criterion for classifying thunderstorms in the cold period of time has been additionally introduced in the WR BZ. To calibrate the values of the criteria, a mathematical apparatus and special software were developed. To collect statistical data, WR BZ were installed in various climatic regions: the Central and North-Western Federal Districts and the Republic of Crimea. Further, an effective validation of the information received was carried out. At present, WR BZ has passed preliminary, acceptance, certification tests, trial operation, while demonstrating an effective classification of meteorological phenomena, thanks to the correct selection of decision criteria. The article considers the possibility of increasing the reliability and justification of the classification of dangerous meteorological phenomena through the additional use of information on the distribution of altitudes of the specific rate of dissipation of turbulent energy of the atmosphere, as well as an additional set of statistical data in various climatic zones of the European territory of Russia – the Upper Volga Region and the Krasnodar Region.

Verification of temperature, wind and precipitation fields for the high-resolution WRF NMM model over the complex terrain of Montenegro.

The necessity of setting up high-resolution models is essential to timely forecast dangerous meteorological phenomena. This study presents a verification of the numerical Weather Research and Forecasting non-hydrostatic Mesoscale Model (WRF NMM) for weather prediction using the High-Performance Computing (HPC) cluster over the complex relief of Montenegro. Verification was performed comparing WRF NMM predicted values and measured values for temperature, wind and precipitation for six Montenegrin weather stations in a five-year period using statistical parameters. The difficult task of adjusting the model over the complex Montenegrin terrain is caused by a rapid altitude change in in the coastal area, numerous karst fields, basins, river valleys and canyons, large areas of artificial lakes on a relatively small terrain. Based on the obtained verification results, the results of the model vary during time of day, the season of the year, the altitude of the station for which the model results were verified, as well as the surrounding relief for them. The results show the best performance in the central region and show deviations for some metrological measures in some periods of the year. This study can give recommendations on how to adapt a numerical model to a real situation in order to produce better weather forecast for the public.

Информационно-аналитическая модель прогнозирования возникновения опасных метеоусловий для оповещения населения

Introduction. Today, security issues in society are more relevant than ever. One of the most important components of safety is the control of weather conditions and monitoring of weather phenomena. Prompt and accurate information about expected meteorological conditions can prevent catastrophic consequences for the population and infrastructure. Therefore, forecasting meteorological phenomena is extremely important for society and the state. The objective of the study. Increasing the level of readiness of the public warning system by developing tools to ensure the safety of people based on the systematization of means of identifying sources of emergencies (including using space technologies), forecasting their development in time and space, as well as a public warning system. Methods. The model is a set of methods of mathematical statistics and machine learning that allow you to analyze the collected data and build forecasts of possible dangerous meteorological phenomena based on them. This paper uses the method of regression analysis, the retrospective method, the Bayesian approach, as well as system analysis and synthesis. Results and discussion. As a result of the study, an assessment of the dynamics of notification before the onset of emergency hazards was carried out. A prognostic model of the hazard level based on multivariate regression analysis has been developed, which includes modeling the threats of dangerous meteorological phenomena using the Bayesian approach. The effectiveness of the developed information-analytical model for predicting the occurrence of dangerous weather conditions for alerting the population is determined. The developed methods are implemented in the computer program "Determination of the level of danger caused by dangerous meteorological phenomena" on the example of the Republic of Crimea. Conclusions. An information and analytical model for predicting the occurrence of dangerous meteorological conditions to alert the population is an important task of the entire state security system. The development of methods of mathematical statistics and machine learning makes it possible to create effective forecasting models that provide timely notification of the population about possible dangerous meteorological phenomena. Keywords: information-analytical model; warning of the population; dangerous meteorological conditions; machine learning; forecasting.

The current regime of heat waves and their impact on the yield of cereal crops in Ukraine

Heat waves are one of the most dangerous meteorological phenomena, the manifestations of which have become more frequent in all regions of the globe in recent decades. Due to excessively high temperatures persisting for a long time, heat waves cause heat stress in living organisms and plants, and negatively affect various sectors of the national economy. Although the mechanism of heat wave formation is well known, the question of determining and predicting the intensity and duration of these processes in advance, as well as the areas of their propagation, remains open, including due to the lack of unified concept of a heat wave. This study analyzed the spatiotemporal distribution of extremely warm days and heat waves for the period 1996-2021 in 16 regions of Ukraine, where the production of the main agricultural crops (winter wheat, spring barley, corn) is concentrated. The analysis was performed using the surface skin temperature Ts, which contains information about the temperature of both the canopy and ground surface.
 It was found that during the study period, the number of extremely warm days increased in all regions of the country and in all seasons of the year, with the most significant increase occurring in the last decade in winter and autumn. The warmest year was 2020, when the number of extremely warm days in some regions reached 100-106 per year. The frequency of heat waves at the end of the study period almost doubled compared to the beginning, reaching an average of 8-10 cases per year. The average seasonal frequency of heat waves was 4-5 cases in summer and 2-4 cases in other seasons. The longest heat waves lasting 17-19 days were recorded in all agro-climatic zones in August 2010. In other seasons, the maximum duration of heat waves did not exceed 10-14 days.
 Statistical assessment of the relationship between the seasonal number of extremely warm days and the grain yield crops showed that an increase in these days in the spring leads to decrease in the yield crops of winter wheat and spring barley; in summer this negative impact is observed for corn.

Features of climate change in the European territory of the Union State of Russia and Belarus

The article is devoted to the assessment of changes in the thermal regime the Republic of Belarus and the European territory of Russia. The relevance of the topic is due to the need to study regional climatic changes in the context of modern global warming. As a result of the study, it was revealed that in the region in the period 1900–2019 in all months of the year the air temperature rises at different rates. Warming occurs more intensely during the December – March period. The dependence of the thermal regime on the type of circulation modes has been established. The fire hazard on the territory of Belarus, the dynamics of dangerous meteorological phenomena depending on the navigation period and the distribution of stratospheric ozone as one of the most important climatic factors are considered.

The effect of climate change on spring frosts and flowering of Crataegus laevigata – The indicator of the validity of the weather lore about “The Ice Saints”

The onset and duration of phenological events are key indicators of the ecological impact of climate change on vegetation. During the flowering time in spring, late frosts are one of the most dangerous meteorological phenomena leading to damage to crops. During 1987–2016, we analyzed the occurrence and intensity of frosts during the period around the weather lore “Frost on the Ice Saints burns all the flowers” in short, “The Ice Saints” and their effects on the flowering phenology of hawthorn (Crataegus laevigata (Poir.) DC.). The late frosts were identified at 0.05 m and2.0 m above ground from temperature measurement data at five phenological stations located from 160 m to 700 m a.s.l. in Slovakia. Results indicate that recent climate change caused the beginning of flowering (BBCH60) for Crataegus laevigata to start significantly earlier by 4.2, 5.0, 6.2 and 3.6 days per decade at 160, 300, 400 and 500 m a.s.l., respectively. Thus, the risk of late frost damage to flowers during “The Ice Saints” is getting highly probable, particularly at 160, 300 and 500 m a.s.l., where the flowering and frosts occur simultaneously. Decreased risk of frost damage during “The Ice Saints” was found at 400 and 700 m a.s.l. It was because of the rare frost occurrence at 400 m a.s.l. in the last decade (2007–2016) of the studied period, and due to the flowering onset dated mostly after “The Ice Saints” at 700 m a.s.l. in the same period.

Ability of the WRF-ARW and HARMONIE-AROME models to detect turbulence related to mountain waves over Central Iberia

Aircraft turbulence is one of the most dangerous meteorological phenomena that can affect aviation safety. This study is focused on the turbulence associated to mountain lee waves in the vicinity of Adolfo Suárez Madrid-Barajas airport (Spain). Sixty-eight mountain lee waves events are selected to simulate the turbulence with the Weather Research and Forecasting (WRF-ARW) and the HARMONIE-AROME numerical weather prediction models. To study and characterize the turbulence associated, the vertical wind speeds are selected as an important variable and the Eddy Dissipation Rate is estimated. Both models have properly simulated the turbulence and the clear air turbulence, obtaining higher values of turbulence intensity by WRF-ARW than HARMONIE-AROME in the mountain lee waves events. Finally, these results are used to enhance a mountain wave warning decision tree, including the turbulence warning which is validated through several turbulence reports.

Об особенностях пространственно-временной изменчивости характеристик волн тепла последних трех десятилетий (Араратская долина, Армения)

The aim of this work to study, identify the repeatability and duration of heat waves of the study area. For it were suggested and decided the following tasks: Findings. The study of regularities of variability of the spatial-temporal distribution of characteristics of heat wave in conditions of regional and global changes of climate is current task of modern geographical science. Extremely high temperatures and heat waves of study area excessively conditioned by the influence of secondary thermal depressions from the Arabian Peninsula, a number of cases that last for 2-3 decades are significantly increased. Tropical thermal depression, forming of extreme hot summers and heat waves, have cycles of activation and weakening, periodicity of which is estimated at 20-22 years. Starting from July (sometimes from the second half of June) to the last ten days of August (sometimes to first half of September), weather conditions of Ararat valley are formed under influence of thermal depression. The invasion of southern and south-eastern tropical warm and dry air currents from the Arabian deserts is increasing. As a result in some years the air temperature in Ararat valley is increased to 40-43 °C, and relative humidity is low than 30%. Heat waves are dangerous weather phenomena, is threat for live and activity, are characterized with some negative consequences. They can be accompanied by droughts and dry winds, forest fires, desertification, disruption of the natural ecosystem, economic damage, decreased working capacity, psychological and sociological consequences, even deaths. Temporal tendencies in course of values of the characteristics of heat wave for last 2-3 decades have positive unambiguous character, more frequent heat waves and extremely warm summers. Heat waves of low and medium intensity have a particularly high frequency. The probability of strong waves is less. The study area is distinguished a characteristic regime and an almost uniform spatial distribution of summer extreme high temperatures. They range from 41,5 to 42,6 °C. The entire study area is vulnerable to heat waves. Heat waves can cause dangerous meteorological phenomena such as droughts or dry winds, which cause great damage to various sectors of the economy, especially agriculture. Therefore the results of the work can be used in the field of agriculture, mitigating and reducing the consequences of possible damage caused. They can also be used in agrometeorological forecasts. In the study area, summer conditions become warmer and drier, which should be taken into account when developing strategic programs for the future development of this area.

Dynamics of climate extremes and trends of dangerous meteorological phenomena in Western Siberia

Dynamics of climate extremes and trends of dangerous meteorological phenomena in Western Siberia

Improving the effectiveness of monitoring of dangerous meteorological phenomena

Three approaches to improving the effectiveness of monitoring of dangerous meteorological phenomena are considered. The first one is based on the modernization of incoherent weather radar on the example of MRL-5 for the possibility of estimating the width of the doppler spectrum by implementing algorithms for pseudo-coherent frequency signal processing with subsampling. Mathematical modeling is carried out, confirming the technical feasibility of the algorithms. On the basis of mathematical analysis, expressions are obtained and graphs of the suppression coefficient of the moving target selection system are presented. The second approach offers a way to improve the efficiency of monitoring for turbulence. An algorithm for detecting zones of increased turbulence and estimating their parameters is proposed. Equations are obtained, on the basis of which algorithms for detecting and estimating the normalized width of the doppler spectrum of zones of increased turbulence, as well as determining the power level of the reflected signals, are synthesized. The third approach describes a way to improve the efficiency of thunderstorm detection and the accuracy of their localization by supplementing the MRL-5 with magnetometric equipment. An example of the implementation and brief technical specifications are given.

Dangerous Meteorological Phenomena and Processes as the Sources of Natural Emergencies: Verbal Model

Dangerous Meteorological Phenomena and Processes as the Sources of Natural Emergencies: Verbal Model

Analysis of the meteorological situation in the conditions of icing and ice

The article is devoted to the study of the problem of ensuring the safety of aircraft on the territory of the Republic of Belarus and, directly, on the territory of the Minsk airfield. Icing and ice are some of the most dangerous meteorological phenomena for aviation. In order to prevent accidents related to these phenomena, it is necessary to have a clear idea of the laws of their occurrence and distribution, as well as their relationship to each other. To study the spatial and temporal patterns of ice distribution, the actual meteorological data of Belhydromet for 1989–2016 were processed at all meteorological stations of the Republic of Belarus. Also, charts of the chronological progress of the average monthly number of days with ice and the average annual number of days with ice at all meteorological stations on the territory of the Republic of Belarus for the above period were constructed and analyzed. The tendency to change the average annual number of days with ice over the period from 1989 to 2016 is analysed. The icing analysis for 2014–2018 was also carried out according to the data of the Civil Aviation Meteorological Station «Minsk». The accompanying meteorological elements, such as the shape of the clouds, the direction and strength of the wind, air temperature, as well as the synoptic situation, are analysed. The map of the spatio-temporal distribution of ice is constructed using ArcGIS by the method of equal intervals.

Calculation of Damage to Buildings and Structures by Lightning According to the Thunderstorms’ Visual and Instrumental Observations

The materials and construction of buildings and structures used should be linked to the number of lightning strikes per year. Lightning protection of buildings and structures should be based on the parameters of thunderstorms in the territory of the project design. Thunderstorm is one of the most dangerous meteorological phenomena. Both ground objects and aircrafts are affected by thunderstorm activity: airplanes and rockets. The main objective of this work is a comparative assessment of the buildings and structures impact by lightning, depending on the methodology for determining the thunderstorms duration in hours for the territories in the North Caucasus. The analysis on the basis of data from the thunderstorm direction finding net (TDFN) of the FSI “VGI” and data from weather stations has been performed. To solve this problem, a study on the relationship between the number of days with a thunderstorm and the duration of thunderstorms in hours for the territories in the North Caucasus has been performed on the FSI “VGI” (TDFN) data basis. In order to determine the above-mentioned statistical characteristics of thunderstorms and their variations in the North Caucasus, for the first time in Russia, the LS 8000 lightning recorder manufactured by “Vaisala” Finland was used.

CHARACTERISTIC OF CONDITIONS OF HEAVY RAINS IN PERM REGION USING ATMOSPHERIC INSTABILITY INDICES

Currently, interest to alternative methods of the analysis and forecasting of dangerous meteorological phenomena has considerably increased due to the low density of the observational network, which is insufficient to provide all users with necessary information in a timely and qualitative way. A general analysis of precipitation characteristics for the period from 2004 to 2016 was conducted during the work. The favorable synoptic conditions for heavy rains precipitation have been identified; their dependence on the altitude was discovered. The aim of this research is to analyze the incidence of heavy rains in the Perm region and to assess instability indexes, which are calculated for specific cases of this phenomenon. For this goal, 5 indices (LI, VT, CN, TT, K) were selected. Their values were calculated in terms of heavy rains based on reanalysis data. It was found that the average settings, which were obtained during the calculation, are slightly lower than the values calculated for other regions and given in previously published researches of this field of science. It means that it is necessary to establish specific indices criteria for the Perm region. Developing of convection and heavy rain in Perm region can be expected when the values of instability indices are near to the calculated values, at which at least 90 % of the total number of cases of the studied meteorological phenomenon occurred. A larger sample should be used to calculate the instability indices for analysis and forecast of heavy rains in practice.

Results analysis of the tests and certification of near-airfield meteorological radar complex

The article presents the tasks, characteristic features, tactical and technical characteristics, the possible location and scope of the near-airfield meteorological radar complex. The analysis is made of the comparison of meteorological radar data from the near-airfield meteorological radar complex with reliable sources of meteorological information obtained during preliminary, acceptance, certification tests. The features of carrying out during the validation tests of meteorological radar data of the near-airfield meteorological radar complex are described, namely: dangerous meteorological phenomena (showers of different intensities, thunderstorms with a probability of 30-70%, 71-90%, > 90%, hail of varying degrees of intensity, squall of different intensities), velocity and direction of movement of cloud formations, vector velocity field. Examples of comparing the data of the near-airfield meteorological radar complex with data from a priori reliable sources of information are shown in the form of maps, graphs and tables. It is shown that the data of the near-airfield meteorological radar complex were obtained during testing and certification covering the warm and cold periods of the year, the sample size is statistically significant (except for the sample to assess the vector velocity field from data of aircraft and radar due to the spatial-temporal features comparing data from the two indicated information sources). It was established that the near-airfield meteorological radar complex provides acceptable in accordance with the requirements the construction quality of meteorological phenomena maps, the vector velocity field and the estimation of the cloud formations movement vector. The article illustrates the results of the statistical analysis of the data of the near-airfield meteorological radar complex, obtained personally by the author of the article. Analysis of meteorological data of the near-airfield meteorological radar complex was carried out with the aim of further exploitation of the near-airfield meteorological radar complex.

Analysis of the height difference of the zero isotherm according to two temperature profilers

One of the main indicators characterizing the quality of meteorological support of flights is the justifiability of aviation weather forecasts and forecasts of dangerous weather phenomena. For the detection and prediction of dangerous meteorological weather phenomena are currently used very advanced systems, which include meteorological radar stations near the airfield zone. The reliability of the forecast of such dangerous weather events as icing, thunderstorms, hail, squally wind according to the information from the meteorological radar stations of the near airfield zone significantly depends on the data on the height of the zero isotherm. The correctness of the entered values of the zero isotherm position directly affects the probability of false alarms, and, consequently, the degree of justification of weather forecasts and forecasts of dangerous weather events. The source of information about the position of the zero isotherm can serve as radiosonding data of the atmosphere. However, the data of aerological radiosonding of the atmosphere are not operational. In addition, at present, obsolete systems are used on Roshydromet aerological network in addition to fairly modern aerological radar systems. This, in conjunction with the sufficiently low cost of the network of aerological stations on the territory of the Russian Federation does not allow the operational use of radiosonding data to determine the height of the zero isotherm at a particular airport. An alternative source of information about the position of the zero isotherm for solving the problems of meteorological location are temperature profilers. Temperature Profiler refers to the remote means of measuring the parameters of the atmosphere, and the principle of its operation is based on the methods of radiometry. Use the temperature of a caliper can be operatively obtain information about the temperature profile at the airport and, therefore, it can be a source for weather radar data on the zero isotherme, and isotherme -22°C, which is also used to identify hazardous weather phenomena. In this paper, the spatial variability of the zero isotherm position is analyzed according to the data of two temperature profilers. As a result of experimental studies, it was determined that within a radius of about 10 kilometers from the installation site of the Profiler, the measured temperature profiles remain virtually unchanged. This result can be used in the development of methods of placement of meteorological support for flights at the airport. Of practical interest are similar studies for airfields located in the mountainous, coastal and other geographical regions of Russia.

Effect of Climate Variability on Agro-climatic Potential of Landscapes of the Chechen Republic

The paper analyzes variability of the agro-climatic parameters of landscapes in the Chechen Republic, which are actively involved in agricultural production. The paper employs statistical and mathematical research methods. Due to climate aridization, agro-climatic conditions were found to deteriorate in 1965–2015 in the plain semi-desert and desert landscapes. Despite the improved thermal and moisture conditions in the plain steppe landscapes, the number of dangerous meteorological phenomena was observed to increase, including those detrimental to agriculture. Owing to the increased period of active vegetation of plants, agro-climatic conditions in the mountain-valley shrub-steppe landscapes of the republic improved compared to those observed in 1931–1960.

Новые вызовы и угрозы возникновения чрезвычайных ситуаций в Республике Беларусь в связи с изменением климата

Цель. Анализ происходящих на планете климатических изменений, определение степени их воздействия на Республику Беларусь, а также выработка основных направлений по смягчению их неблагоприятных последствий. Методы. Анализ статистических данных об опасных и неблагоприятных природных явлениях на территории Беларуси, а также зарубежного опыта по противодействию неблагоприятным климатическим явлениям. Синтез направлений и мер по смягчению неблагоприятных последствий чрезвычайных ситуаций природного характера на территории Беларуси на основе проведенного анализа. Результаты. Представлен анализ обстановки с природными чрезвычайными ситуациями на территории Республики Беларусь с 2008 по 2017 год. Показано, что изменение климата определенным образом влияет на статистику чрезвычайных ситуаций природного характера, вызывая неблагоприятные явления, которые ранее на территории Республики Беларусь не наблюдались (например, ураганные ветры). Отмечено увеличение экономического ущерба от типичных для белорусских широт погодных проявлений при незначительном росте количества чрезвычайных ситуаций, вызванных климатическими изменениями и опасными метеорологическими явлениями. Проведен анализ зарубежного опыта по противодействию неблагоприятным климатическим явлениям. Предложены меры по смягчению неблагоприятных последствий чрезвычайных ситуаций природного характера на территории Беларуси. Область применения исследований. Полученные результаты могут быть применены при разработке планов и рекомендаций по смягчению неблагоприятных последствий чрезвычайных ситуаций природного характера.