Icing Events Research Articles

Industrialization and innovation strategy of event resources in ice and snow sports under the background of big data

This article examines the industrialization and innovative strategy of event resources in ice and snow sports in the context of big data. Based on this analysis, the article proposes a path and development strategy for the Chinese sports industry, which includes encouraging the industrialization of the nation’s ice and snow sports industry. It is important to evaluate ice and snow sports in order to improve competitive results and optimize training techniques using big data technologies. Despite using a variety of techniques to evaluate performance, their inability to fully capture the complex patterns found in ice and snow sports events presents difficulties. In order to assess and enhance sports talents, therefore we proposed a new method using ISSE-Apriori algorithms. The pre-processed data gathered before extracting the most important and relevant features. The experiment results section analyzes the resources of ice and snow sports cities. The results examine sports event strategies, taking into account predictions and actual accuracy results, the GDP growth rate, the efficiency of industrial development, and a comparison of Apriori before and after enhancement. The experimental result is validating using measures like recall, accuracy, and precision. In addition, we conducted a comparative analysis with the current approaches to confirm the efficiency and robustness of the proposed methodology. The Suggested approach is implemented with Python Software. The Suggested Approach’s performance is measured in terms of RMSE (0.3524), MAE (0.1832), MAPE (4.24) with large dataset. The results stated that the proposed methodology has provided an accuracy of 98.42%.

ИЗМЕНЕНИЯ ПРОДОЛЖИТЕЛЬНОСТИ БЕЗЛЕДНОГО ПЕРИОДА ПО ДАННЫМ БЕРЕГОВЫХ НАБЛЮДЕНИЙ В КАРСКОМ МОРЕ

Based on observations for the timing of ice events at 12 coastal stations in the Kara Sea, the longterm means and trends are calculated for start dates, end dates and duration of ice-free period (IFP) for 1979–2020. The obtained results were compared with the calculations for the same IFP parameters based on passive microwave remote sensing data. An increase in the duration of the ice-free period is observed at 9 of the 12 stations considered. This happens both due to the shift of the start dates of the IFP (observed at 8 out of 12 stations) to earlier dates, and due to the shift of the end dates of the IFP to later dates (noted at 11 out of 12 stations). A comparison of long-term means and trends of the start, end dates and duration of the IFP between satellite data and coastal observations confirms that remotes sensing microwave data (sea ice concentration) can be used to analyze the interannual variability of IFP characteristics in the coastal zone of the Kara Sea. It is shown, that the results obtained using the proposed modified threshold method (MPM) are in a better agreement with the coastal observation data than the widely used threshold 15 % method.

Geothermal bridge deck de-icing using a novel external hydronic heating system with insulated pipe loops

A geothermal-based external hydronic heating system (EHHS) has been developed as an effective solution to address the de-icing needs of in-service bridges with minimum negative impacts on the structure, traffic, and environment. This paper discusses the implementation and operational response of a new design of the EHHS in which rather than the whole bottom surface of the bridge deck, only the hydronic heating loops are covered with insulation material and provides the accessibility for visual inspection of the bridge deck. The first full-scale external hydronic heating system with an insulated loop (EHHS-IL) was installed on a mock-up bridge deck in north Texas and tested in a record snowstorm with a low ambient temperature of −19.5 ˚C. The system operated in three different stages, and the inlet fluid temperature was adjusted according to the weather forecast. Overall, during a 10-day operation, three ice and snow events and 209 hours of freezing ambient temperature were observed. The heating system was able to maintain the heated bridge deck surface temperature above freezing except for 1.3 hours when the −19.5 ˚C low ambient temperature coincided with snowfall. The average surface heat flux during the test varied from 34.8 – 84 W/m2, and the average heating efficiency was estimated at 17.7 %. The seasonal performance factor (SPF) of the system remains consistently greater than 1 during the heating period. Also, 422 kWh of electrical energy was consumed during 10 days of operation by the entire geothermal de-icing system. This new geothermal bridge deicing system offers a practical solution to icy bridges by retrofitting.

Investigation of anchor ice evolution in rivers and the impact of hydrometeorological conditions

The evolution of anchor ice during river freeze-up is known to significantly influence sediment transport, fish habitats, and river hydrology during winter. It may also lead to the formation of anchor ice dams and the generation of anchor ice waves that can cause flooding. Many of the previous field studies of anchor ice focused on the conditions leading to its formation and release, its crystal structure and properties, and the evaluation of its impacts. However, direct measurements of the temporal variation of anchor ice in rivers are rare, which has limited our understanding of this important and dynamic ice form. In this study, six anchor ice events were measured on two Canadian rivers using an underwater camera system, accompanied by comprehensive measurements of weather and hydraulic data and frazil ice concentrations. The temporal evolution of anchor ice was observed to occur in one of three stages: growth, stable, or decay. The direction (i.e., upward or downward) and trend of the net air–water heat flux reliably indicated the timing of these three stages. Anchor ice growth in the majority of events was through a combination of frazil accretion and in-situ crystal growth, resulting in event-averaged growth rates from 0.48 to 1.77 cm/h. Anchor ice grew solely through frazil accretion when snowfall occurred, with event-averaged growth rates from 1.64 to 3.53 cm/h. Anchor ice decay occurred through the thermal thinning of accumulations at an average decay rate of −0.48 to −2.52 cm/h. Anchor ice release was controlled by thermal factors and always occurred after the end of supercooling. Frazil accretion rates were estimated using measurements of anchor ice growth rates and suspended frazil concentrations and ranged from 2.6 × 10−3 to 6.0 × 10−3 m/s.

Direct and indirect costs of parasitism preceding a population decline of an Arctic ungulate

Parasites negatively affect the fitness of ungulate hosts directly, and in wild ungulates, these effects may be synzootic with other stressors, such as limited nutritional resources. In the Arctic, muskoxen (Ovibos moschatus) occur in a highly seasonal environment and must rely on finite energetic resources for survival and productivity. We investigated the costs of gastrointestinal nematodes on the body condition and reproductive status of 141 muskoxen, on Banks Island, Canada, when the population was at a peak in numbers and density. Using a Partial Least Squares Path Modelling approach, we found that high adult nematode abundance was associated with lower body condition, and high parasite abundance was associated with female reproduction including the indirect effect through on body condition (n = 87). These findings suggest that individuals prioritize energetic reserves for reproduction over parasite defence. In fall 2003, a severe icing event that restricted access to forage was associated with high overwinter mortality of muskoxen and a population crash. Through direct and indirect costs of parasite infection on body condition and reproduction, the high abundance of parasites may have contributed to the effects of this extreme weather event. Understanding the mechanisms in which parasites impact fitness can help explain the ecological drivers of ungulate populations and predict the interactions between the environment and populations.

Impact of Meteorological Factors on the Wire Icing Thickness and Growth Rate in Mountain Areas under Dry and Wet Growth Patterns

Wire icing events pose a significant threat to the southern power grid’s transmission lines in China. Fifteen such events were identified from 2018 to 2020 on the Guilin-Haiyang Mountain transmission line. Hourly measurements of ice thickness and concurrent meteorological data were analyzed using the Makkonen model’s freezing rate formula to categorize the events into distinct growth patterns: dry and wet. The relationship between wire icing and meteorological factors across different micro-topography (windward slope, leeward slope, and pass) was further explored. Several key conclusions can be drawn. First, the altitude is positively correlated to the icing thickness, but relatively independent of the icing rate; however, such independence between the icing rate and altitude cannot be interpreted by the negative correlation of altitude with temperature and the positive relationship between wind speed and liquid water content. Second, a pronounced connection of the icing rate with meteorological factors is not shown until the wet and dry patterns are separated. Notably, the correlations differ between these two patterns, with icing rate being negatively correlated with temperature for the wet growth process, but positively correlated with wind speed and liquid water content for the dry growth process. Third, both wet and dry growth processes exist across the icing events. A shift from wet to dry growth was evident with increasing altitude. At the mountain’s base, wet growth predominates, with the icing rate determined by the temperature close to the freezing point, whereas the higher temperature and lower liquid water flux account for the shorter wire icing duration, lower icing rate, and thus the thinner icing thickness at the leeward slope compared to the windward slope at a similar altitude. This study sheds light on the variations in icing rates under different micro-topographies and the underlying physical mechanisms governing icing growth patterns and provides a much-needed understanding of these distinct growth processes on the development of a more sophisticated predictive model for conductor icing.

Performance-based ice engineering framework: A data-driven multi-scale approach

Ice storms are one of the most devastating natural hazards which have the potential to inflict significant damage to the built environment. The multi-hazard nature of ice events complicates the analysis of their induced risk due to their inherent nonlinear interactions. In addition, the concurrent and interacting hazards are often responsible for several aerodynamical/dynamical instabilities such as the galloping mechanism. Moreover, the existing risk approaches are usually not suited for large-scale risk evaluation over extended geographical regions due to the involved high-computational costs. Therefore, in this study, a novel data-driven multi-scale performance-based ice engineering (PBIE) framework is developed to support the design of new structures subjected to ice storms or the rehabilitation of existing ones. In addition, the proposed PBIE is capable of rapidly estimating the real-time risk over an extended region due to an ice event. Specifically, it leverages the superior capabilities of state-of-the-art data-driven techniques (e.g., machine learning) to efficiently generate the corresponding risk maps and identify the high-risk areas. The proposed PBIE framework is applied to a simplified example in which the galloping-induced risk on iced conductors, in terms of the galloping amplitude, is evaluated for both local and regional scales. The resulting PBIE framework can be readily applied for design or retrofitting purposes or integrated within an emergency response management system to inform preventive actions that can mitigate the ice storm-induced damages and save lives.

Towards blade-resolved ice accretion simulations of flexible blades using mixed-fidelity models

We present a modular framework for blade-resolved fluid-structure interaction simulations of rotors. The framework is based on the coupling of the multi-body solver MBDyn with the fluid solver SU2 using the library preCICE. A preliminary validation is carried out against other open-source codes analysing the UAE Phase VI experiment. In the future, the framework will be used to study ice accretion on flexible blades. Indeed, blade flexibility has not been considered yet in the numerical modelling of ice accretion due to lacking computational tools and high computational costs. A first application on ice accretion is shown by analyzing the temporal evolution of the modal frequencies of an isolated blade during an icing event simulated numerically with a quasi-3D approach. The results provide insight into the nature of ice throw from wind turbines.

Transformative Ecological and Human Impacts from Diminished Sea Ice in the Northern Bering Sea

Abstract Our goal is to tie climate-scale meteorology to regional physics and ecosystem changes and demonstrate a few resulting impacts to which regional peoples are having to respond in the Alaskan Bering Strait region. The sea ice loss events in the winters of 2017/18 and 2018/19 initiated a series of marine environmental, ecological, and industrial changes through a chain of connected events from jet-stream meanders, storms, southerly winds, warmer sea temperatures, and minimum sea ice cover. Resulting impacts continue as coastal communities respond to ongoing nutritional, cultural, and economic challenges. Global warming potentially initiated these events through a weakened atmospheric Arctic Front. Ecological shifts included a transition/reorganization of the Bering Strait regional marine ecosystem. Subsequent changes included shifts in zooplankton species, increases in large-bodied, predatory fish species moving northward, an ice seal unusual mortality event, and seven consecutive years of multispecies seabird die-offs. These changes in the marine ecosystem create a serious food security concern. Ongoing impacts include large, toxic harmful algal blooms and coastal erosion. Recent changes to the maritime industries of the transboundary waters of the Bering Strait include increased industrial ship traffic, planned development of the Port of Nome, and northward proximity of foreign fishing activity. Projections for the next decades are for an increasing frequency of low sea ice years and continuing ecosystem and industrial transitions that contribute to increasing economic and food security concerns for the 16 coastal communities that compose the Bering Strait region. Significance Statement Extreme events in the atmosphere/oceans and resultant record sea ice minimums in 2018 and 2019 were manifested in marine ecosystem transitions and maritime industry impacts. This led to ongoing concerns over the food safety and food security of marine resources essential to the nutritional, cultural, and economic well-being of Alaskan coastal communities of the Bering Strait region. Persistent weakening of the Arctic Front may signal an increased frequency of low sea ice events into the next decades.

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.

Meteorological Characteristics of a Continuous Ice-Covered Event on Ultra-High Voltage Transmission Lines in Yunnan Region in 2021

Yunnan plays a pivotal role in transmitting electricity from west to east within China’s Southern Power Grid. During 7–13 January 2021, a large-scale continuous ice-covering event of ultra-high voltage (UHV) transmission lines occurred in the Qujing area of eastern Yunnan Province. Based on ERA5 reanalysis data and meteorological observation data of UHV transmission line icing in China’s Southern Power Grid, the synoptic causes of the icing are comprehensively analyzed from various perspectives, including weather situations, vertical stratification of temperature and humidity, local meteorological elements, and atmospheric circulation indices. The results indicate a strong East Asian trough and a blocking high directing northern airflow southward ahead of the ridge. Cold air enters the Qujing area and combines with warm and moist air from the subtropical high pressure of 50–110° E. As warm and cold air masses form a quasi-stationary front over the northern mountainous area of Qujing due to topographic uplift, the mechanism of “supercooling and warm rain” caused by the “warm–cold” temperature profile structure leads to freezing rain events. Large-scale circulation indices in the Siberian High, East Asian Trough, and 50–110° E Subtropical High regions provided clear precursor signals within 0–2 days before the icing events.

Assessment of atmospheric circulation impacts on the Caspian Sea level and ice regime

The research aimed to assess the influence of atmospheric processes in the Northern Hemi-sphere’s Atlantic-European Sector on the Caspian Sea level based on the data for the days with Wangenheim-Girs atmospheric general circulation forms. The inputs covered the time period from 1900 to 2022. The information on the sea level, precipitation and ice events were harvested from 22 observation points in Kazakhstan and Russia. The statistical and comparative analysis as well as the climate change assessment within the framework of the study pointed to a stable correlation between the sea level and atmospheric circulation; re-vealed certain patterns reflected in precipitation distribution and frequency of moisture defi-cient and excessive years. The research also identified that the climatic changes have al-tered the sea’s ice regime, with the maximum ice thickness decreasing by 13-28 cm depend-ing on a specific water area. In addition to ice thickness variation, the recent decades show an increased frequency of moderate and mild winters, and the shift of the main glaciation dates, i.e. a stable ice cover forming later, the date of fixed maximum ice thickness observed in mid-February, the date of complete ice clearing observed in early-mid March, and the freezing period being shorter.

Exploring the atmospheric and weather conditions for hoar frost formation at OR Tambo International Airport: A case study of ground aircraft icing events for the period 2017-2023.

Exploring the atmospheric and weather conditions for hoar frost formation at OR Tambo International Airport: A case study of ground aircraft icing events for the period 2017-2023.

The Synoptic Characteristics of Icing Events on Transmission Lines in Southern China

This study utilizes the ECMWF ERA5 climate reanalysis database and data from the Southern China Transmission Lines Icing Observation System and applies the T-mode principal component analysis, an objective synoptic pattern classification method, to investigate synoptic characteristics associated with transmission line icing events in southern China between 2014 and 2021. The findings reveal that Southern China’s winter synoptic conditions can be categorized into four patterns, with the predominant pattern featuring a centrally located 850 hPa high-pressure system in Inner Mongolia’s western region. This pattern facilitates the convergence of northwesterly cold air from the north and southwesterly moisture from the south over southern China, resulting in balanced conditions conducive to transmission line icing. Furthermore, during a specific icing event in Zhaoqing City, Guangdong Province, in February 2022, the atmospheric stratification exhibited a distinctive “cold–warm–cold” structure with a pronounced inversion layer, characteristic of freezing and rainy weather conditions that create the requisite environment for transmission line icing. Within the dominant icing synoptic pattern, a northwesterly airflow transports cold air from central Siberia to southern China, accompanied by two primary low-level water vapor transport pathways: one originating as a southwest low-level jet carrying moisture from the Bay of Bengal to the Chinese mainland, and the other stemming from the South China Sea. These findings provide valuable insights into the synoptic conditions contributing to transmission line icing events in the region.

Investigation of the Effect of the Instrument Landing System on Flights to Konya Airport between 2019-2022 Years

The Instrument Landing System (ILS) is the most widely used navigation aid system among the precision approach types, which enables the pilots to approach the runway in the appropriate direction and glide slope, especially in foggy and snowy weather when the visibility is very low. This study investigated the relationship between flight disruptions and ILS in Konya Airport. In this context, meteorological events such as snow, ice, fog, and cancellation, divert and delay events caused by humans (company policy) at Konya Airport in the period of 2019-2022 were revealed with numerical data. In light of these data, it has been revealed that ILS not only provides safe flights but also prevents possible passenger complaints and financial losses by reducing the number of diverts, and therefore ILS is also of great importance in terms of customer satisfaction.

Characterization of icing conditions using aircraft reports and satellite data

A sample of 115 aircraft icing events in the Western Europe and Northeastern Atlantic sector, identified in aircraft pilot reports (PIREPs), is assessed in terms of spatio-temporal distribution and cloud characteristics, using satellite observations and products. Within our database, most of the reported events occur between October and February, although a few cases were identified during late spring and even summer months. Icing conditions are generally reported at mid-troposphere, with 82.7% and 78.6% of moderate and severe icing, respectively, identified between FL100 and FL250 (≈ 3–7.6 km). Satellite observations allow the identification of icing-prone conditions and also provide an independent means of validating some of the data in the aircraft reports. It is shown that icing occurs mainly within opaque clouds, with ice cloud-tops, or mixed phase (ice and water), noting the severe events, take place mostly under mixed-phase cloud-tops. Accordingly, most events were associated with middle and high opaque clouds, with 10.8μm brightness temperatures (BT10.8) between −40 and − 8 °C. Moreover, a detailed analysis of three events, making use of model, satellite and synoptic observations, illustrates the occurrence of aircraft icing in precipitating clouds. Within those cases, one occurred below the upper layer of a thick nimbostratus associated with an occluded low centred in the Bay of Biscay. The second event, reported as severe, as in the former case, took place within low clouds over southern England in association with northwesterly winds driven by a complex low. Finally, a moderate event happened over southern Portugal in association with a cold front, near the cloud top of nimbostratus. In all cases, the icing index operational at the Portuguese Weather Service, based on the European Centre for Medium-range Weather Forecasts (ECMWF) model, was able to predict prone-icing conditions, with higher severity in the severe cases.

Microclimate Analysis of the High-Impact Weather for the Power Grid Operation in the Jibei Region of China

High-impact weather affects the safety and economic operation of power systems. In this study, to provide regional microclimate of high-impact weather for the local power grid system in the northern Heibei province (known as the Jibei region in China), ERA5-Land global reanalysis data during 1981–2020 with a 0.1° grid size (about 9 km) are adopted to analyze the climate statistics and changes of the disastrous weather that affects the power grids. The results show that there have been significant climate changes in the region, including a temperature increase of about 1 °C, evident humidity and precipitation reductions, for the Jibei region and the six sub-regions that concentrated with wind and solar energy development in the 40 years. Due to the differences in terrain, the climate changes differ significantly among the six renewable energy development regions. The main types of high-impact weather that affect the power grid in the region are heavy fog and icing events, followed by cold waves, snowstorms, and rainstorms. In general, with climate changes in the last several decades, the weather disasters in Jibei region have become more frequent. Since most high-impact weather events have a small scale, it is necessary to simulate the weather processes with high-resolution models to accurately quantify the characteristics of the weather processes that affect the power grid. Therefore, a refined regional meteorological model (with grid size of 2 km) based on four-dimensional data assimilation (JB-FDDA) is established for the Jibei region. With one year of model reanalysis data, we found that JB-FDDA can significantly improve the accuracy of the local meteorological fields, and properly depicted the details of severe weather that affect the power grid operation. This study provide an analytical approach for regional electricity meteorological disasters by using reanalysis data.

Frazil ice events: Assessing what to expect in the future

Abstract This article addresses the question: What is expected from frazil ice activity in rivers, taking into account the changing climate? It begins with an overview of what frazil ice is and what is required for the occurrence of frazil ice events, namely a supercooled water column. Methodologies to anticipate frazil ice events in the short term are based on air temperature and water discharge, underlining the significance of these two parameters for any predictive methods. Longer-term approaches, calibrated against past events (hindcasting), are used to anticipate frazil ice activity into the future, with indicators such as frazil ice risk, water temperature and frazil volume. Any of these approaches could conceivably be applied to frazil-prone river stretches. To assess climate impact, each location should be treated separately. River ice dynamics can lead to the formation of a hanging dam, a frequent outcome of frazil ice generation in the early winter, causing flow restriction. Flood modeling and forecasting capabilities have been developed and implemented for operational use. More frequent mid-winter breakups are expected to extend the occurrence of frazil ice events into the winter months – the prediction of these will require climate model output to adequately capture month-to-month variability.

Ice Accretion: Image Post-Processing Measurement Techniques for 2D Ice Shapes

Ice accretion poses substantial safety hazards for the manned and unmanned aviation industries. Its study is essential for icing events risk assessment and for the development of efficient ice protection systems. The existing ice accretion measurement techniques—casting, molding, and laser-scanning—are time-consuming, sometimes cumbersome to use, and highly expensive, while hand tracing is inexpensive, but has lower accuracy and time-consuming post-processing. This work presents two low-cost, fast, and easy-to-use measurement techniques for 2D ice accretion profiles. Both employ algorithms of automatic ice shape detection, one based on unmediated image-processing, another based on the processing of manual ice tracings. The techniques are applied to ice accretion experiments conducted in an icing wind tunnel at low Reynolds numbers, and their results are validated against ice thickness caliper measurements. A comparison of the results shows that both techniques accurately measure the leading-edge ice thickness and the 2D shape of the ice accretion profiles. One technique is faster, with higher measurement accuracy, but produces interrupted-line 2D ice profiles and requires good lighting conditions, while the other generates continuous-line 2D profiles and has no application restriction, but it is slower, with lower accuracy. A discussion is conducted, aiming to help one determine the best applications for each ice accretion measurement technique presented.

Understanding ice accretion on wind turbines with field data

With the abundance of wind resources in cold climates, a significant share of the worldwide wind energy installed capacity is located in those areas. However, the advantages of cold climate operation comes with challenges associated with ice accretion. Throughout the years, alternative operational strategies have been developed to cope with these challenges. Although many strategies, such as blade heating, have been commercially available for a long time, few field studies have investigated their performance. Evaluating the performance of wind turbines in cold climates is a hard task due to the lack standards and the variability of external factors influencing turbine behaviour. In this paper, a methodology to assess the performance of wind turbines in cold climates is illustrated with a case study. This methodology aims to provide a better understanding of how ice accretion impacts wind turbine performance. This methodology was exemplified with a case study where the performance of a turbine equipped with a retrofit hot air ice protection system was analyzed over a 9-day icing event. It was found that the usage of the cold climate solution yielded an average energy gain of 159 MWh and an average potential recovery of 62%.