Rain Phenomenon Research Articles

Effects of coronal rain on decayless kink oscillations of coronal loops

Decayless kink oscillations are ubiquitously observed in active region coronal loops with an almost constant amplitude for several cycles. Decayless kink oscillations of coronal loops triggered by coronal rain have been analyzed, but the impact of coronal rain formation in an already oscillating loop is unclear. As kink oscillations can help diagnose the local plasma conditions, it is important to understand how these are affected by coronal rain phenomena. In this study, we present the analysis of an event of coronal rain that occurred on 25 April 2014 and was simultaneously observed by Slit-Jaw Imager (SJI) on board Interface Region Imaging Spectrograph (IRIS) and Atmospheric Imaging Assembly (AIA) on board the Solar Dynamic Observatory (SDO). We investigated the oscillation properties of the coronal loop in AIA images before and after the appearance of coronal rain as observed by SJI. We find signatures of decayless oscillations before and after coronal rain at similar positions to those found during coronal rain. The individual cases show a greater amplitude and period during coronal rain. The mean period is increased by 1.3 times during coronal rain, while the average amplitude is increased by 2 times during rain, in agreement with the expected density increase from coronal rain. The existence of the oscillations in the same loop at the time of no coronal rain indicates the presence of a footpoint driver. The properties of the observed oscillations during coronal rain can result from the combined contribution of coronal rain and a footpoint driver. The oscillation amplitude associated with coronal rain is approximated to be 0.14 Mm. The properties of decayless oscillations are considerably affected by coronal rain, and without prior knowledge of coronal rain in the loop, a significant discrepancy can arise from coronal seismology with respect to the true values.

Robust, thermally insulating, and high-temperature resistant phosphate-enhanced mullite fiber porous ceramic composites

Porous mullite ceramics with high porosity and low thermal conductivity are urgently required as high-temperature thermal insulators in harsh environments. How to improve the strength of Porous mullite ceramics dramatically under the premise of no sacrificing its thermal insulating properties has remained an extremely challenging. Inspired by the freezing rain phenomenon in nature, high-strength and high-temperature resistant phosphate coatings were applied to the surface of mullite fibers, which significantly improved the mechanical properties of porous mullite ceramics without significantly increasing their thermal conductivity. The Al(H2PO4)3 solution concentration significantly affected the mechanical and thermal properties of the composite material, where the mechanical performance improved with an increasing Al(H2PO4)3 solution concentration. The phosphate coating phase stabilized with an increasing calcination temperature. The mechanical properties of the ceramics were improved by the excellent interfacial bonding strength between the coating and mullite fiber, and the forms of phosphate in the porous ceramics. The optimum composite preparation process increased its compressive strength by approximately nine-fold to 4.1 MPa and resulted in a thermal conductivity of only approximately 0.09 W/(m·K), demonstrating that the composite exhibited a significantly higher comprehensive performance than other previously reported porous ceramics and aerogels. Such new composites with excellent mechanical and thermal insulation properties exhibit excellent potential for high-strength thermal insulation in the chemical, metallurgical, pharmaceutical, aerospace, and other fields.

MASSA TETES AIR HUJAN DALAM ALQURAN (Analisis Ilmiah QS. Az-Zukhruf Ayat 11)

This research particularly examines the meaning of "بقدر" in QS. Az-Zukhruf verse 11 by applying the science of climatology to rainwater levels. This study aims to provide new knowledge regarding the meaning of levels in QS. Az-Zukhruf verse 11. The phenomenon of rain falling to the earth is a natural process and we often feel. The phenomenon of rainwater falling to the earth has a level that has been determined by Allah in the Qur'an to be a mercy, but we often encounter natural disasters caused by the presence of rainwater that falls beyond the capacity of water reservoirs on earth. Thus, to reveal the meaning of the level of rainwater, it takes the discipline of Climatology as an analytical approach. Along with this study, the author applies the Science of Climatology to reveal the calculation of levels in QS. Az-Zukhruf verse 11.This research is a literature study (Library Research) using qualitative research methods, by collecting several paperwork from commentators and scientific scientific journals. The primary data used in this study is the Qur'an QS. Az-Zukhruf verse 11 and books on climatology.The results of the research on the mass of raindrops in Al-Qur’an by implementing the discipline of Climatology are to reveal the meaning of rainwater content in QS. Az-Zukhruf verse 11 and the results of the calculation of the mass of raindrops in the Quran.

The Effects of Freezing Rain on Forest Stands Administered by Zalău Forestry Department During 2014-2022 Period

Freezing rain is a rare and extremely dangerous meteorological phenomenon, consisting of the fall of liquid precipitation, while the air temperature at ground level falls below 0oC, favoring the freezing of raindrops and forming an ice sheet on the surfaces on which they are deposited. In Romania, the areas affected by the freezing rain phenomenon undergo significant changes regarding the structure and composition of the forest vegetation. The main purpose of this work is to figure out how to manage the forest stands affected by the freezing rain identifying optimal solutions for ecological reconstruction and prevention of significant damages. For the research of the affected areas, we placed 7 experimental areas, having the size of 500 m2 each, all the trees that were in this radius were inventoried. In this research work we evaluate the presence of this phenomenon which was reported in the Stejarul Zalău Forest District, in 2014, then in 2017, but with a lower intensity. Out of a total of 1627.6 ha, 500 ha were affected by the freezing rain, most of them being surfaces with beech forest stands with a consistency of 0.9, having a high slenderness index. Following the results obtained, it was observed that the most affected trees were the youngest. These having a reduced diameter, thin branches and a high slenderness coefficient.

Soliton rain in all-polarization-maintaining mode locked fiber laser.

For the first time the phenomenon of soliton rain is observed in a mode-locked fiber laser with all-polarization-maintaining (all-PM) architecture. The laser is mode-locked using a semiconductor saturable absorber mirror (SESAM) and operates in the all-normal dispersion (ANDi) regime. The operation state of the laser can be switched from dissipative soliton to soliton rain by simply raising the pump power, without any manipulation of the intracavity polarization state given that all components of the resonator are made of PM fibers. The soliton rain generated in the laser is self-starting and replicable, since it occurs in every individual operation of the laser as the pump power is increased to an approximately invariant value.

The Study of Air Pressure System and Extreme Rain in The Southern Java Island

Extreme rain can trigger other natural phenomena that can interfere with human activities. Rain phenomenon extremes are common in tropical cyclones. This study aims to characterize the occurrence of extreme rain events concerning the air pressure system on Java Island. This study uses rainfall data from GSMAP MVK Product and Sea Level Pressure (SLP) from NCEP/NCAR Reanalysis. The identification of extreme rain is carried out with pixel detection of the GSMAP precipitation data from 2015 to 2019. The most extreme rain events were then ranked, and ten events with the highest rain rate were selected. The SLP data at the selected extreme rain event was analyzed and plotted as a map. The principal result shows that in the 10 highest extreme rain events, 4 of them occurred due to the influence of low-pressure systems and tropical cyclones. The rest are associated with other climatic phenomena. In conclusion, this study shows that extreme rainfall tends to be associated with low-pressure anomalies over the Indian ocean. However, not all of the low-pressure anomalies were intensified as a tropical cyclone. Therefore, extreme rainfall in Southern Java Island can be developed due to small air pressure differences.

Measuring Students' Scientific Argumentation Skills in Explaining Phenomena Related to Acid-Base Concepts

Scientific argumentation is one of the main competencies of students in communicating chemical phenomena through the application of conceptual mastery that they have understood. The development of this ability has been postulated in the 2013 curriculum through constructivist-based learning approaches and scientific inquiry, either in the classroom or the laboratory. However, there is relatively little information on how students' scientific argumentation skills develop. This study aims to measure students' scientific argumentation skills in explaining five science phenomena related to the acid-base concept, namely: acid rain, salt crystal making, the use of antacids as ulcer medicine, the use of CaMgCO3 dolomite fertilizer, and the difference in the acidity level of HCl and H2SO4, using Rasch modeling. Each phenomenon was measured by three multiple-choice test items, which were developed to test students' ability to make claims (Q1), evidence (Q2), and justification (Q3). The data were analyzed using Rasch modeling, allowing researchers to measure the item and individual respondent levels. Respondents were 100 chemistry students in Gorontalo, who were differentiated in gender and adversity quotient. The results showed that the measurement instrument has good validity and reliability. In addition, it was found that students' abilities differed; some items responded differently regarding gender and adversity quotient. Most students tended to be weak in explaining the phenomenon of acid rain, the use of antacids for ulcer disease, the use of dolomite fertilizer, and the difference in the acidity level of HCl and H2SO4

A brief analysis of ChatGPT：historical evolution， current applications，and future prospects

近年来，人工智能技术接连取得突破，尤其是在强化学习、大规模语言模型和人工智能生成内容技术等方面，正逐步成为各个行业的创新驱动力。OpenAI于2022年11月30日发布的ChatGPT由于具有惊人的自然语言理解和生成能力，引起全社会大范围的关注，成为全球热议的话题，并被广泛应用于各个行业。仅两个月后，ChatGPT的月活跃用户数便达1亿，成为史上用户数增长最快的消费者应用。鉴于ChatGPT目前造成的影响，对其进行全面的分析较为必要。本文从历史沿革、应用现状和前景展望这3个角度对ChatGPT进行剖析，探究其对社会的影响、技术的原理和挑战以及未来发展的可能性，并从模型能力的角度简要介绍GPT-4相对于ChatGPT的改进。作为一个现象级技术产品，从技术角度而言ChatGPT对相关领域具有里程碑式的重要意义，从应用角度而言其可能会给人类社会带来巨大的影响。ChatGPT有潜力成为计算机领域最伟大的成就之一。但就目前而言，ChatGPT仍然存在一些局限，尚未达到强人工智能的水平。在当前阶段，研究人员需要对人工智能技术持有自信和谦虚学习的态度，继续发展相关的技术研究和应用。;Artificial intelligence（AI）technology has been developing intensively，especially for such scenarios in relevance to its applications of 1）natural language processing，2）computer vision，3）recommendation systems，and 4）forecast analysis. AI technology has been challenging for human cognition over the past decade. In recent years，natural language processing techniques can be focused on more. ChatGPT，as a case of emerging generative AI technology，is launched in December of 2022. ChatGPT，as an advanced language model，is commonly used on the basis of its a）larger model sizes，b）advanced pre-training methods，c）faster computing resources，and d）more language processing tasks. This ChatGPT-related literature review is focused on its（1）public awareness and application status，（2）characteristics， （3）mechanisms，（4）scalability，（5）challenges and limitations，（6）future development and application prospects，and （7）improvements of GPT-4 relative to ChatGPT. Cognitive computing and AI-based ChatGPT can be as a sort of language model in terms of the Transformer architecture and Generative Pre-Training（GPT）. This GPT-trained model can be related to natural language processing，which can predict the probability distribution of the next token using a multi-layer Transformer to generate natural language text. It can be outreached by training the learned language patterns on a large corpus of text. The OpenAI’s language model has shown a significant improvement in their level of intelligence from GPT-1（117 million parameters）in 2018 to GPT-3（175 billion parameters）in 2020. The language processing and generation capabilities of GPT have been improving dramatically in terms of consistent optimization like its 1）model size，2）generative models， and 3）self-supervised learning. Thereafter，reinforcement learning-based InstructGPT is originated from Human Feedback and such probability of infeasible，untrue，and biased outputs can be significantly reduced in January 2022. In December 2022，ChatGPT is introduced as the sister model of InstructGPT. ChatGPT is not only add InstructGPT-based chat attributes，and a test version is opened to the public. The core technologies of ChatGPT can be linked to 1）reinforcement learning from human feedback（RLHF），2）supervised fine-tuning（SFT），3）instruction fine-tnning（IFT），and 4）chain-ofthought （CoT）as well. ChatGPT has attracked about 100 million active users per month after the launch of two months. In comparison，TikTok took nine months to achieve 100 million monthly active users，and Instagram took two and a half years. According to Similar Web，more than 13 million independent visitors use ChatGPT on average each day in January of 2023，which is more than twice in December of 2022. The leading US new media company Buzzfeed accurately seized the opportunity of ChatGPT and saw its stock price triple in two days. The ChatGPT-derived impact shows its potential preference for consumers. The ChatGPT can play mulitiple roles for such domain like clinics，translation，official administrations，and programming tasks. Such extensive application of ChatGPT is still to be developed. However，while ChatGPT has the potential for widespread application in various industries，it cannot be universally applied to all industries. For example，as certain industrial production processes typically rely on digitalization and do not necessitate the handling of human language，natural language processing techniques may not be required. Furthermore，various other factors，such as legal restrictions and data privacy concerns，may also impinge upon the application of natural language processing technologies within certain industries. For industries that require the processing of sensitive information，such as the healthcare industry，natural language processing technologies may need to comply with strict legal regulations to ensure data privacy and security. In addition to industry-specific reasons，it should be noted that ChatGPT has not yet achieved perfection in natural language processing tasks. In summary，as a phenomenal and technological product，AI-generated ChatGPT’s potentials are beneficial for textual and multi-modal AIGC applications to a certain extent，and it may have an impact on the a）survival of corporations，b）competition among countries，and c）entire social structure. However，the current various positive evaluations of ChatGPT can only be seen as a phenomenon of good rain after a long drought，and it cannot change the fact that ChatGPT is a questions and answers（Q&A）solution based on prior knowledge and models. It is required to be acknowledged that ChatGPT does not have its true recognition，intention，and creativity yet，and its true intelligence need to be tackled further.

EFFICIENCY OF CREATIVE THINKING ABILITY IN AUGMENTED REALITY-BASED LEARNING MEDIA THE ACID RAIN THEME

This research was conducted due to the lack of students' awareness of the phenomenon of acid rain. The phenomenon of acid rain can be harmful to health and ecosystems. Whereas acid rain can be prevented by increasing the awareness of students through improving the quality of education, especially the ability to think creatively which is expected to help find solutions to minimize the impact of acid rain. However, students in Indonesia have a low quality of education which causes students' creative thinking skills to be low. This study aims to determine the efficiency of Augmented Reality-based learning media in the development of creative thinking skills of seventh grade students on the theme of Acid Rain. Augmented Reality-based learning media is a technology that combines 2D and 3D virtual objects from interactive applications, thus helping in growing students' creative thinking skills. The research method used is Research and Development (R&D) according to Thiagarajan (1974) which was adapted based on the 4-D model. This model consists of 4 stages of development, namely define, design, develop, and disseminate. But the research is limited to the develop stage, because this research only focuses on the efficiency level of the Augmented Reality-based learning media developed. The results of the study based on the efficiency test of learning media based on Augmented Reality with the theme of acid rain for class VII SMP obtained an average value of 88.54% in the very efficient category. Keywords: Learning Media Based on Augmented Reality, Acid Rain, Creative Thinking Ability .

INTEGRATION OF CHARACTER VALUES IN THE RAIN PHENOMENON BY SCIENCE AND Al-QURAN

One of the goals of Indonesian National Education is to develop the potential of students to become human beings who believe and are devoted to God Almighty. These goals can be formed through character education by inserting religious values in learning. One of them is in learning science which is integrated with the holy verses of the Koran. Science is a subject in school that discusses the phenomenon of rain. This research is a library research. The data collected in this study consisted of primary data obtained from the holy book of the Koran and secondary data in the form of data obtained from research articles. The data collected in this study were analyzed into information. The data in the study are in the form of verses from the Koran that discuss the phenomenon of rain which is studied for scientific evidence, so that the relationship between science and the Koran can be seen. Through this integration between science and the Koran, character values can be learned from the rain event. Based on the results of the study, it was found that rain is a hydrological cycle. Water on earth evaporates and rises to the atmosphere in the form of water vapor which then condenses at a certain height to form clouds. These clouds will move because of the wind so that they collect in one place and eventually condense into rain in the form of liquid, snow, or ice crystals which eventually fall back to earth. Rainwater that falls to the earth provides many benefits for the survival of humans, plants, and animals. The character values that can be learned from the rain event include acknowledging the oneness and majesty of God, being grateful for favors, and praying for goodness every time it rains to get blessings.

Survey of Radiometric Techniques for Prediction of Meteorological Phenomena

Objectives: The present work illustrates an extensive review of the field of prediction of meteorological phenomena using radiometric measurements and machine learning with specific focus on rain events and their effects on satellite communication. Methods: Multiple types of prediction systems and mechanisms are reviewed, with focus on estimation of atmospheric phenomena using standard statistical models and radiometric measurements, with additional focus on the application of modern machine learning-based techniques for accurate estimate generation. Recent work in the domain has been compared, largely in tabular format, with respect to critical statistics such as correlation coefficient, root mean square error, and computational complexity of the techniques. Findings: The systems and mechanisms reviewed allow the identification of opportunities in establishment of novel techniques for prediction of meteorological effects and their influence on parameters such as communication signal attenuation. It is also established through the work that there is lack of a suitably accurate model for prediction of rain attenuation for geographical regions prone to greater variations in weather, such as the tropical regions. Consequently, some of the most recent work in this domain has been analyzed in this paper with a view to determine optimal techniques for different scenarios. Novelty: The survey identifies the opportunity to improve upon established models for prediction of rain phenomena and their effects on microwave and millimeter wave communication signal attenuation, as well as surveys modern estimation techniques in detail, with a specific focus on statistical and machine learning based methods which can guarantee greater accuracy with significant variation in the observed parameters such as brightness temperature and rain rate. The work seeks to clearly compare some of the newest techniques in the domain with respect to their efficiency as well as complexity, for practical applications. Keywords: meteorological phenomena; prediction; radiometric measurements; microwave; millimeter wave; brightness temperature; machine learning

Prediction of Rainfall in Australia Using Machine Learning

Meteorological phenomena is an area in which a large amount of data is generated and where it is more difficult to make predictions about events that will occur due to the high number of variables on which they depend. In general, for this, probabilistic models are used that offer predictions with a margin of error, so that in many cases they are not very good. Due to the aforementioned conditions, the use of machine learning algorithms can serve to improve predictions. This article describes an exploratory study of the use of machine learning to make predictions about the phenomenon of rain. To do this, a set of data was taken as an example that describes the measurements gathered on rainfall in the main cities of Australia in the last 10 years, and some of the main machine learning algorithms were applied (knn, decision tree, random forest, and neural networks). The results show that the best model is based on neural networks.

Mainstreaming climate resilience: A GIS-based methodology to cope with cloudbursts in Turin, Italy

Cities play an increasingly significant role in the challenges posed by climate change, mainly due to their role in economic and demographic drivers. It is generally agreed that the intensification of climate change effects, such as extreme weather events, requires strengthening in the mechanisms of adaptation and the endogenous self-organization of urban systems. An operative way to adapt is by mainstreaming climate resilience, i.e., the iterative process of integrating climate change considerations into policymaking, budgeting, implementation, and monitoring processes at national and subnational levels. This paper falls under this heading, and it aims at building an innovative methodology to experiment with data-driven approaches to support the resilient transition of the city of Turin in Italy. The process aims to create territorial knowledge of specific weather phenomenon, that cloudburst events are, by filling the gap of existing hazard information with original vulnerability datasets. The proposed approach will create a hydraulic vulnerability map by identifying cloudburst vulnerable areas with a GIS-based spatial overlay. The paper will employ an array of datasets combined with original modelling techniques elaborated with the help of the open-source InVEST (Integrated Valuation of Ecosystem Services and Trade-offs) software program. The results allow us to understand what would happen if the urban water network failed to discharge during a phenomenon of intense rain and, consequently, which city areas should undergo adaptation and transformation to reduce their flooding vulnerability.

Coronal Rain in Randomly Heated Arcades

Abstract Adopting the MPI-AMRVAC code, we present a 2.5-dimensional magnetohydrodynamic simulation, which includes thermal conduction and radiative cooling, to investigate the formation and evolution of the coronal rain phenomenon. We perform the simulation in initially linear force-free magnetic fields that host chromospheric, transition-region, and coronal plasma, with turbulent heating localized on their footpoints. Due to thermal instability, condensations start to occur at the loop top, and rebound shocks are generated by the siphon inflows. Condensations fragment into smaller blobs moving downwards, and as they hit the lower atmosphere, concurrent upflows are triggered. Larger clumps show us clear coronal rain showers as dark structures in synthetic EUV hot channels and as bright blobs with cool cores in the 304 Å channel, well resembling real observations. Following coronal rain dynamics for more than 10 hr, we carry out a statistical study of all coronal rain blobs to quantify their widths, lengths, areas, velocity distributions, and other properties. The coronal rain shows us continuous heating–condensation cycles, as well as cycles in EUV emissions. Compared to the previous studies adopting steady heating, the rain happens faster and in more erratic cycles. Although most blobs are falling downward, upward-moving blobs exist at basically every moment. We also track the movement of individual blobs to study their dynamics and the forces driving their movements. The blobs have a prominence-corona transition-region-like structure surrounding them, and their movements are dominated by the pressure evolution in the very dynamic loop system.

Water droplet bouncing on pre-frosted superhydrophobic carbon soot — A step forward in designing passive icephobic surfaces

The devastating repercussions of natural freezing rain phenomena on a variety of industrial facilities might be avoided if the surface-under-attack is designed to be superhydrophobic, thus, repelling the impacting supercooled droplets and remaining free of ice. Regrettably, in climate regions with negative temperatures and highly humid atmosphere, the supersaturated water vapor freezes within the micro- nanocavities of the non-wettable surface and droplet bouncing associated with superhydrophobicity could no longer be preserved. This article explores the possibility of fabricating superhydrophobic carbon soot coatings that would maintain droplet rebound even if their surface is covered with frost. By analyzing the droplet impact dynamics on two groups of frosted soot coatings, differing by morphology, roughness, surface chemistry and porosity, we show for the first time that the liquid meniscus impalement can be cancelled when the soot consists primarily of macropores and oxygen functional groups below 7 at. %. Such a surface configuration ensures minimum energy losses (qualitatively defined) right after the dynamic collision due to the sparsely inceptive ice bridges that normally enhance the heat transfer at the contact interface. The results reported herein could be a useful platform for developing universal icephobic surfaces applicable to harsh environments.

Comparison of some schemes for determining the optimal number of rain gauges in a specific area: A case study in an urban area of South Sulawesi, Indonesia

<abstract> <p>Improving the accuracy of rainfall forecasts is related to the number of rain gauges needed in an area, so determining the optimal number of rain gauges is very important. This study aimed to determine the best method for calculating the optimal number of rain gauges. Generally, the calculation of the optimal number of rain gauges using the coefficient of variation only takes into account the accumulation of rainfall at the station. The distance between the location and height of the rain gauge is not taken into account. The phenomenon of rain that occurs in the tropics is very dynamic, where one place compared to another tends to have different rain intensity and duration. In addition, the height and distance factors also greatly affect the measured rainfall. Therefore, it is very important to know the best method to calculate the optimal number of rain gauges needed in a particular area. This study implements 3 methods to determine the appropriate method to be used in determining the optimal rain gauge number for urban areas: namely, World Meteorological Organization (WMO) criteria, coefficient of variation, and Kagan-Rodda. In this study, rainfall data from 2010 to 2019 at 5 locations in Makassar were used in calculating the optimal number of rain gauges required. The results showed that the optimal number of rain gauges in Makassar as an urban area following the WMO recommendation was 9–18, where small islands around it are not considered. Another result obtained is that if the rainfall data for the Sudiang area, which is located at the coordinates (119.522° E, 5.085° S), is not included in the calculation, it will greatly reduce the accuracy in determining the optimal number of rain gauges in the Makassar area.</p> </abstract>

Freezing rain phenomena. Case study: Bucharest metropolitan area, January 24-29, 2019.

The paper has a structure with four parts and presents the climatic risk aspects that happened in Romania during the winter of the year 2019, concentrating on Bucharest, where a very rare and dangerous phenomenon occurred, `freezing rain`. The first part contains the theoretical analysis of the subject under discussion (the notion of risk and freezing rain), in the second part we analyzed the synoptic context (the causes that led to the phenomena) and the datacollected, the third part presents the results of the research (the duration of phenomena and the case study in the city), and the last part deals with proposed measures in order to reduce the risk of freezing rain, measures that can apply to any dangerous weather phenomena with freezing deposits. Therefore, the study aims to analyze this risk starting from the theoretical explanation of the synoptic context that generated its production to the quantitative analysis of the phenomena. To achieve this objective, the periods ECMWF models and the synoptic databases were accessed, with the help of which the representation and evolution of the phenomena was managed.

Analisis Kondisi Atmosfer Saat Kejadian Hujan Lebat dan Angin Kencang di Probolinggo Berdasarkan Citra Satelit dan Citra Radar

The phenomenon of extreme weather, heavy rain and strong winds hit four sub-districts in Probolinggo Regency, East Java on January 3, 2020 at 17.00 WIB. Based on data from the East Java Regional Disaster Management Agency (BPBD), the incidence of heavy rain and strong winds resulted in damage to as many as 204 houses. This study uses remote sensing data in the form of C-Band Radar and Himawari-8 Satellite and Copernicus ECMWF renalysis data. The data is processed into spatial maps and graphs which are then analyzed descriptively. The results of data analysis show that the reflectivity value reaches 43 dBZ and the wind speed reaches 13.57 m / s with a rainfall of 15.83 mm / hour at 10.00 WIB. Based on the analysis of the Himawari-8 Satellite, the peak temperature of the clouds reached -73.1 oC and the atmospheric lability data showed that the atmosphere was unstable, which could indicate the possibility of heavy rain and strong winds. The value of vortices in the 1000 mb - 500 mb layer is negative and the humidity value ranges from 85% - 90% and a positive sea surface temperature anomaly value and the presence of windshields result in convergence of air masses which can support convective cloud growth as the cause of heavy rain events and strong winds in Probolinggo Regency, East Java

Determination of sky status by ground based radiometric data analysis

Objectives: To predict meteorological phenomena such as rain events from sky status during rainy and non-rainy periods. Methods: The method used here is based on brightness temperature ratio measurement at two different frequencies, namely 23.8 GHz and 30 GHz respectively, using ground based dual frequency radiometric data. The ratios of brightness temperature readings obtained by the dual-frequency radiometer at the two above mentioned frequencies are calculated for each simultaneously-taken pair of measurements. Data obtained by the authors for the year 2009 at Cachoeira Paulista in Brazil has been used for analysis. Findings: The major results obtained from the analysis of data collected over a continuous period of seven months are used to construct corresponding histograms and cumulative count graphs of brightness temperature ratios. The histograms and graphs clearly show three peak values that could be interpreted as thresholds between clear sky, cloudy sky and rainy sky conditions respectively. Novelty: The study implements detection of rain events from sky status during rainy and non-rainy periods using peak brightness temperature values obtained from graphs generated using the observation data. The outlined technique can therefore be used to clearly determine sky conditions and accurately predict rain phenomena. The ratio of brightness temperatures at the two frequencies is a unique parameter which is critical to the successful estimation of rain from sky status. The results agree well with multi-channel radiometric data obtained by other researchers at lower frequencies. Keywords: sky status; microwave; millimeter wave; dual frequency radiometer; brightness temperature; rainfall

ACID RAIN-CAUSES, EFFECTS AND PREVENTIVE STRATEGIES

Acid rain was discovered in the 19th century by Robert Angus Smith, a pharmacist from Manchester (England), who measured high levels of acidity in rain falling over industrial regions of England and contrasted them to the much lower levels he observed in less polluted areas near the coast. Little attention was paid to his work until the 1950s, when biologists noticed an alarming decline of sh populations in the lakes of southern Norway and traced the problem to acid rain. Similar ndings were made in the 1960s in North America (the Adirondacks, Ontario, Quebec). These ndings spurred intense research to understand the origin of the acid rain phenomenon. In this research paper we will investigate and take a look at the key factors and the chemical origins of acid rain and the steps undertaken to prevent it.