Ice Formation Research Articles

Witnessing a discrete microdroplet freezing event via real-time electrochemical monitoring of solution temperature.

Temperature monitoring has immediate relevance to many areas of research, from atmospheric environmental studies to biological sample and food preservation to chemical reactions. Here, we use a triple-barrel electrode to provide temperature readouts in bulk solution and microdroplets, as well as electrochemically monitor freezing events in a microdroplet. Using this method, we are able to identify distinct characteristics of a freezing aqueous droplet (supercooling, ice formation beginning and end, temperature change, and thawing) with greater temporal resolution than a standard thermocouple and without the use of microscopy. By correlating the amperometric signal change caused by alterations in the diffusion coefficient of the electrochemical system in response to temperature changes, we can calculate the instantaneous temperature at our electrode, as well as the physical behavior of ice formation and expansion. Our results suggest that these electrochemical techniques can provide real-time monitoring of the physical processes involved in aqueous temperature change and ice nucleation events. Here, we employ a novel technique using triple-barrel electrodes to provide temperature readouts in bulk solution and microdroplets, as well as electrochemically monitor freezing events in a microdroplet. Because ice nucleation spans many research fields, it is important to have a variety of tools that can be used to better understand these frozen systems. Our data shows that electrochemistry can provide real-time information on the thermal properties of aqueous environments, and these types of measurements can be extended to microdroplets. The electrochemical signal details all the significant moments in a droplet freezing event, allowing us to use electrochemistry as a stand-alone tool for monitoring freezing events with excellent temporal and spatial resolution.

Review of exploration of aircraft de/anti-icing mechanism and airborne application of superhydrophobic materials

The aircraft surface icing changes the flight dynamics characteristics of the aircraft and seriously threatens flight safety. Therefore, aircraft de/anti-icing technologies are of great significance for safe flight. The basic principle, type, and influence of aircraft icing are analyzed and the existing de/anti-icing technology methods and their advantages and disadvantages are compared. Literature review of superhydrophobic materials was comprehensively conducted, and its specific conditions (superhydrophobic property failure) were analyzed, especially the existing problems and challenges. A hybrid de/anti-icing system was proposed for the defects of a single de/anti-icing system, and several hybrid de/anti-icing systems were introduced and compared with the single de/anti-icing system. In addition, aiming at the possible problems in the application of superhydrophobic materials, an aircraft de/anti-icing system combining loop heat pipe and superhydrophobic materials is presented. Benefiting from the efficient heat transfer mode of the loop heat pipe system and the superhydrophobic effect of the superhydrophobic material, this method can not only reduce the energy consumption of the aircraft?s de/anti-icing system, but also reduce the formation of secondary icing. Finally, the issues of superhydrophobic coating and hybrid de/anti-icing systems are analyzed and prospected.

Natural beauty of modern art philosophy: evaluation of the art form of sport ice and snow sculpture in landscape architecture

Natural beauty of modern art philosophy: evaluation of the art form of sport ice and snow sculpture in landscape architecture

Upper-Ocean Processes and Sea Ice Production in the Southeastern Amundsen Sea Polynya in Austral Autumn

Abstract The mixed layer of polynyas is vital for local climate as it determines the exchange of properties and energy between ocean, sea ice, and atmosphere. However, its evolution is poorly understood, as it is controlled by complex interactions among these components, yet highly undersampled, especially outside summer. Here, we present a 2-month, high vertical-resolution, full-depth hydrographic dataset from the southeastern Amundsen Sea polynya in austral autumn (from mid-February to mid-April 2014) collected by a recovered seal tag. This novel dataset quantifies the changes in upper-ocean temperature and salinity stratification in this previously unobserved season. Our seal-tag measurements reveal that the mixed layer experiences deepening, salinification, and intense heat loss through surface fluxes. Heat and salt budgets suggest a sea ice formation rate of ∼3 cm per day. We use a one-dimensional model to reproduce the mixed layer evolution and further identify key controls on its characteristics. Our experiments with a range of reduced or amplified air–sea fluxes show that heat loss to the atmosphere and related sea ice formation are the principal determinants of stratification evolution. Additionally, our modeling demonstrates that horizontal advection is required to fully explain the mixed layer evolution, underlining the importance of the ice-covered neighboring region for determining sea ice formation rates in the Amundsen Sea polynya. Our findings suggest that the potential overestimation of sea ice production by satellite-based methods, due to the absence of oceanic heat flux, could be offset by horizontal advection inhibiting mixed layer deepening and sustaining sea ice formation.

Factors affecting winter performance of Ultra-Thin Bonded Wearing Course (UTBWC)

ABSTRACT Ultra-Thin Bonded Wearing Course (UTBWC) surfacing was developed as a preventative maintenance option to extend pavement life. Despite the successful applications of UTBWC in various states, feedback indicates that severe icing and snow accumulation occur during winter storms. Similar concerns have been identified by other states. Therefore, the objective of this study was to investigate how prevalent the problem is, to assess the winter performance of UTBWC compared to adjacent dense graded hot mix asphalt (HMA) surfaces and to determine whether any issue is dependent on temperature, snowfall, mixture properties or traffic using geospatial and statistical analysis. Survey responses from districts indicated that more than half of the sections experienced moderate snow accumulation and ice formation issues. The geospatial analysis showed that such issues may not be dependent only on temperature and/or snow accumulation. Statistical analysis on mix design and quality assurance (QA) indicated that mixture air voids play an important role. While this study considered all UTBWC sections in the state, it represents an initial assessment, and thus it is recommended that additional data over time should be used for further validating the results and analysis. Finally, recommendations for improving winter maintenance operations were provided.

Microplastics in Southern Ocean sea ice: a pan-Antarctic perspective

Microplastic (MP; plastic particles < 5 mm) pollution is pervasive in the marine environment, including remote polar environments. This study provides the first pan-Antarctic survey of MP pollution in Southern Ocean sea ice by analyzing sea ice cores from several diverse Antarctic regions. Abundance, chemical composition, and particle size data were obtained from 19 archived ice core samples. The cores were melted, filtered, and chemically analyzed using Fourier-transform infrared spectroscopy and 4,090 MP particles were identified. Nineteen polymer types were found across all samples, with an average concentration of 44.8 (± 50.9) particles·L-1. Abundance and composition varied with ice type and geographical location. Pack ice exhibited significantly higher particle concentrations than landfast ice, suggesting open ocean sources of pollution. Winter sea ice cores had significantly more MPs than spring and summer-drilled cores, suggesting ice formation processes play a role in particle incorporation. Smaller particles dominated across samples. Polyethylene (PE) and polypropylene (PP) were the most common polymers, mirroring those most identified across marine habitats. Higher average MP concentrations in developing sea ice during autumn and winter, contrasting lower levels observed in spring and summer, suggest turbulent conditions and faster growth rates are likely responsible for the increased incorporation of particles. Southern Ocean MP contamination likely stems from both local and distant sources. However, the circulation of deep waters and long-range transport likely contribute to the accumulation of MPs in regional gyres, coastlines, and their eventual incorporation into sea ice. Additionally, seasonal sea ice variations likely influence regional polymer compositions, reflecting the MP composition of the underlying waters.

Justification of the scheme of melting ice on the wires of overhead power lines

The article discusses an urgent problem related to the formation of ice and frost deposits on the wires of overhead power lines, which causes significant technical difficulties in ensuring the reliability of power supply, especially in winter. The accumulation of ice and frost on the wires leads to an increase in the weight of the wires, which can cause them to sag, damage insulators, destroy poles, and, as a result, serious accidents on power lines. The causes of accidents in power grids due to ice and frost deposits are analyzed and it is found that their elimination will reduce the probability of damage to overhead power lines from the action of ice loads. However, existing methods of dealing with this problem have a number of disadvantages, such as high cost, low efficiency in certain conditions, and negative environmental impact. The article presents a scheme for melting ice on the wires of overhead power lines by the method of a three-phase short circuit when powered by a power source with a solidly grounded and isolated neutral. This scheme makes it possible to locally increase the temperature of wires to a level sufficient to melt ice and frost, which reduces the risk of emergencies and ensures the uninterrupted operation of the electrical grid. The article provides theoretical justifications for the scheme for melting ice with three-phase short-circuit currents, which confirm its effectiveness. The analysis has shown that the proposed scheme is economically feasible, as it reduces the cost of maintenance and repair of overhead power lines. In addition, it is environmentally friendly, as it does not involve the use of chemicals. Thus, the proposed scheme for melting ice on the wires of overhead power lines is a promising solution for improving the reliability and safety of power supply in winter weather conditions. Its application can significantly increase the efficiency of power grid operation, reduce the number of accidents, and improve the stability of power supply to consumers.

ИСПОЛЬЗОВАНИЕ НАБЛЮДЕНИЙ АРГО ДЛЯ ИССЛЕДОВАНИЯ МЕЖГОДОВОЙ ИЗМЕНЧИВОСТИ ТЕПЛООБМЕНА ПОЛЯРНЫХ МОРЕЙ С АТМОСФЕРОЙ, АТЛАНТИЧЕСКИМ И СЕВЕРНЫМ ЛЕДОВИТЫМ ОКЕАНАМИ И ИНТЕНСИВНОСТИ ЛЕДООБРАЗОВАНИЯ

The annual mean temperature, salinity, density, and velocity fields for the region of the Nordic Seas were calculated and studied using the Argo-based model for the period of 2005–2014. The heat transports through the Denmark and Fram Straits, and through the sections separating the Nordic Seas from the Atlantic Ocean and Barents Sea were studied on the climatological, annual, and seasonal time scales. The calculated transports are in good agreement with the previous estimations. The methodology of the mean ice formation rate estimation is discussed.

Wind, Wave, and Ice Impacts on the Coastal Zone of the Sea of Azov

The coastal zone of the Sea of Azov is a dynamic environment influenced by various natural and anthropogenic factors, including wind, wave action, beach material removal, and cultivation on cliff edges. The coastal zone of freezing seas is also influenced by ice cover during winter. This study investigates the dynamics of the Sea of Azov’s coastal zone during winter (2014–2023), focusing on the impacts of waves and ice, to identify the most vulnerable coastal areas. We analyzed high-resolution satellite imagery and employed mathematical modeling to obtain data on ice pile-up, fast ice formation, wind patterns, and storm wave dynamics within the shallow coastal zone. Long-term wind data revealed an increase in maximum wind speeds in December and January, while February and March showed a decrease or no significant trend across most coastal observation stations. Storm waves (significant wave height) during the cold season can reach heights of 3.26 m, contributing to coastal erosion and instability. While the overall ice cover in the Sea of Azov is decreasing, with fast ice rarely exceeding 0.85% of the total sea area, ice pile-up still occurs almost annually, with the eastern part of Taganrog Bay exhibiting the highest probability of these events. Our analysis identified the primary impacts affecting the shallow coastal zone of the Sea of Azov between 2014 and 2023. A map was generated to illustrate these impacts, revealing that nearly the entire coastline is subject to varying degrees of wave and ice impact. Exceptions include the eastern coast, which experiences minimal fast ice and ice pile-up, with average or lower dynamic loads, and the southern coast, where wind–wave action is the dominant factor.

The Role of Geometry on the Ease of Solidification Inside and Out of Cylindrical Nanopores.

We investigated the role of a nanoporous particle on the formation of macroscopic solid in the framework of equilibrium thermodynamics and from the free-energy perspective. The model particle has cylindrical pores with equidistant circular openings on the particle surface. We focused on two potentially limiting steps: (i) the solid nucleation from liquid inside a single pore and (ii) the bridging of multiple pores on the particle surface. We examined the nucleation near the liquid-vapor meniscus inside a pore by considering different solid-vapor and solid-pore wall contact angles, as well as the liquid-vapor meniscus angles. For bridging, we quantified the effects of the proximity of neighboring pores and the number of participating pores where we considered two or three pores, placed two different distances apart, and three contact angles of the solid with the particle surface. Except in special cases where an analytical solution could be developed, we determined the equilibrium nucleus and bridge shapes numerically using the Surface Evolver code. The geometry of these equilibrium shapes was the key for correctly calculating the energy barriers. Our results indicate that the meniscus angle can be an important factor in reducing the barrier for nucleation if the internal angles of the solid nucleus satisfy a certain criterion. For the solid growth out of the pores, we found that the barriers were significantly lower in the presence of multiple, closely packed pores compared to the growth from a single pore. This paper is deliberately written with no reference to material properties or a specific process to highlight the generality of geometry-controlled barriers. A direct application where our findings can be particularly valuable is the ice formation in clouds, which is the subject of intensive research in atmospheric sciences for its role in influencing precipitation patterns and hence the climate.

Global Biomass Burning Emission Contributions to Ice Nucleating Particles

AbstractBiomass burning (BB) can produce ice nucleating particles (INPs) and influence cloud ice formation and climate effects, but the distribution and budget of BB‐induced INPs are not well understood. This study quantified INPs from BB at −17°C to −30°C and explored their spatiotemporal distributions. The results indicate that the INPs of BB aerosol were 5.42 × 1021 in 2019, approximately two orders of magnitude lower than those of dust aerosol, but much more than those of marine organic aerosol. Globally, INPs from BB were mainly influenced by wildfires, but in regions like East Asia, residential BB contributed significantly, accounting for about 57%. INPs from BB would have more pronounced effects in high latitudes of the Northern Hemisphere and parts of the Southern Hemisphere, particularly during peak wildfire periods. Thus, BB should be unignorable in evaluating the fates and impacts of INPs.

Examination of land surface temperature variations due to urban growth

Land surface temperature refers to the analysis of heat on the surface of the earth. It is identified by measuring the surface using Thermal Infrared wavelength, which includes areas such as rooftops, building tops, water bodies, and ice formations. This research aims to examine land surface temperature and land use using satellite data spanning 5 years (2019-2023). The process consists of three primary stages: 1) Analyzing land surface temperature with data from Sentinel-3 Satellite through the Supplemental Nutrition Assistance Program (SNAP) initiative, 2) Employing data from Sentinel-2 Satellite for land-use classification using supervised classification with maximum likelihood classifier, categorizing land-use into water, forest, urban, and agriculture, 3) Conducting accuracy assessment. The findings from the 5-year research revealed that urban areas exhibit the highest average land surface temperature, with forests, agriculture, and water areas following in descending order.

Length-dependent water permeation through a graphene channel.

Water confined in two-dimensional channels exhibits unique properties, such as rich morphology, specific phase transition and a low dielectric constant. In this work, molecular dynamics simulations have been used to study the water transport in two-dimensional graphene channels. The structures and dynamics of water under confinement show strong dependence on the channel length and thickness of the channels. In particular, there exists a critical channel length beyond which monolayer water forms square-like ice structures, leading to the rapid decrease in water flow that eventually ceases completely. The water flow for double-layer and three-layer systems exhibits a similar exponential decay but does not reach zero. The translocation time exhibits an excellent power-law behavior with an increase in the channel length, accounting for the exponential flow decay. The radial distribution function confirms the length-dependent liquid-to-ice phase transition of monolayer water and the liquid states for double-layer and three-layer systems. The formation of monolayer ice can be further supported by the increasing barriers in the potential of mean force and specific dipole distributions. Furthermore, the melting temperature of monolayer ice increases significantly with the increase in the channel length that can also be close to or even exceeds the boiling point at atmospheric pressure. These findings provide new physical insights into the extraordinary length-dependent water behaviors and suggest future experimental studies on high-temperature ice through the size control in nanochannels.

Lidar measurements of noctilucent clouds at Río Grande, Tierra del Fuego, Argentina

Abstract. Noctilucent clouds (NLCs) are sensitive tracers of upper-mesospheric temperature, water vapor, and dynamics and thus open windows to study our atmosphere from very large to very small scales, including topics of climate, circulation, waves, and turbulence. NLCs are weaker in the Southern Hemisphere compared to the Northern Hemisphere where there are numerous observations, but no vertical soundings at Southern Hemisphere mid-latitudes were available until now. We determine the properties of NLCs above a Southern Hemisphere mid-latitude site at 53.8° S in southern Argentina. The Compact Rayleigh Autonomous Lidar has provided high-resolution vertical lidar soundings since 2017. Noctilucent clouds are detected every summer, with the earliest (latest) detection on 29 November (29 January), giving 19 events in total of 33.8 h length at an average height of 83.3 km, a maximum brightness of 24 × 10−10 m-1sr-1, an occurrence rate of 7 %, and a maximum in the morning hours (05:00–07:00 UTC, i.e., 02:00–04:00 LT). The latter coincides with a positive amplitude of the semi-diurnal tide of the meridional wind as measured by the Southern Argentina Agile Meteor Radar. The ambient temperature above the site is on average too high to support local ice formation. We find no correlation with the solar flux; indeed, the latest season of 2023/2024 shows the most NLC detections. This leaves transport from more southerly and colder regions and potentially increasing upper-mesospheric water vapor levels as a result of increasing space traffic as possible explanations for the occurrence and unexpectedly large brightness of NLCs above Río Grande.

Zoobenthos of the freezing water bodies of the “Medvezh`i ostrova” Nature Reserve, East Siberian Sea

While monitoring the Polar bear in the “Medvezh`i ostrova” (= Bears’ Islands) Nature Reserve in October 2023, a number of mainland water bodies were surveyed: the lakes “Nesolyonoe” and “Unnamed”, the Krestovaya River, the “Unnamed” watercourse on Chetiryokhstolbovyi Island, as well as the sea bay of Kolyma Bay, all in the East Siberian Sea. Representatives of zoobenthos were found in each of the water bodies studied, but the fauna was not very diverse. A total of only 7 species of benthic invertebrates were revealed in the surveyed water bodies of the Bears’ Islands Nature Reserve, of which 3 species were found in sea water: Pacifoculodes pallidus (G. O. Sars 1892) (Amphipoda), Yoldiella nana (M. Sars 1865) (Bivalvia), and Enchytraeus albidus Henle 1838 (Oligochaeta). In the water bodies feeding the Galgavaam River, 2 species from the family Chironomidae and 3 species of eurytopic Oligochaeta were recorded. Their abundance ranges from 0.20 to 1.70 thousand ind./m2 and 0.10 to 3.70 g/m2 biomass in freshwater bodies, vs not exceeding 0.60 thousand ind./m2 and 1.90 g/m2 biomass in the sea. Seasonal cohorts are formed there, 37% of which are merohydrobionts (Сhironomidae) and amphibiotic Оligochaeta, and 13% each are neritic amphipods and bivalves. The formation of seasonal cohorts is determined by a short growing season and an extended ice formation on island and mainland watercourses and reservoirs.

Influences of Sprinkler Frost Protection on Air and Soil Temperature and Chlorophyll Fluorescence of Tea Plants in Tea Gardens

Sprinkler irrigation is an effective method for protecting economic crops from frost damage; however, current research on its impacts is insufficient and lacks comprehensive evaluation. This research investigated the effects of sprinkler irrigation for frost protection on the air, soil, and tea plants in the tea garden. Sprinkler frost protection experiments were conducted in the tea garden, where temperature sensors measured the air and soil temperatures, and Monitoring-PAM was used to measure the chlorophyll fluorescence parameters (Fv/Fm) of the tea plants. The results indicated that lower initial ambient temperatures or smaller droplet sizes accelerate the rate of air temperature increase and slow the cooling rate. Under conditions of heavy frost, ice formation from irrigation water acts as an insulating layer, protecting the inter-row soil. Additionally, the Fv/Fm values of tea leaves protected by sprinkler irrigation ranged from 0.6 to 0.7, and were significantly higher than those of leaves exposed to frost damage. The results also showed that air and soil temperature and tea Fv/Fm can be used to perform a comprehensive assessment of sprinkler frost protection effectiveness.

THE ORIGIN OF ICE MOUNDS NEAR THE ERKATA-YAKHA RIVER, YAMAL PENINSULA, FROM THE RELATIONSHIP BETWEEN δD AND δ18О ISOTOPE RATIOS

Ice mounds are widespread cryogenic landforms that occur during freezing of water-saturated sediments and in ice segregation or ice injection with the formation of ice cores. Complex mechanisms of occurrence of these landforms have their own characteristics depending on the type of enclosing sediments, water and gas saturation, freezing rate, and other factors. Ice formation processes are often accompanied by explosions of the central part with the occurrence of negative landforms. In response to the widespread occurrence of perennially frozen gas-saturated rocks, these processes are accompanied by gas emissions, gas inflammation. and other, less intense gas shows. It is quite difficult in these conditions to determine the causes of the catastrophic phenomenon, to reconstruct the dynamics of the process, and to understand the role of gas-saturated fluids. In this paper, an attempt has been made to determine the ice formation conditions using isotopic techniques. The isotopic composition of ice can reflect the conditions of ice formation at the time of occurrence of ice mounds and its related possibility of participation of gas-saturated fluids from deep-lying gas-bearing horizons [Buddo et al., 2023, 2024]. The composition of stable isotopes δD and δ18O was determined for three ice mounds in the south of the Yamal Peninsula, where there were catastrophic explosions of ice mounds with the formation of large craters. The results of the study made it possible to reconstruct the conditions of ice mound occurrence and to determine different ice formation modes.

Influence of Lamb Wave Anisotropy on Detection of Water-to-Ice Phase Transition.

An important technical task is to develop methods for recording the phase transitions of water to ice. At present, many sensors based on various types of acoustic waves are suggested for solving this challenge. This paper focuses on the theoretical and experimental study of the effect of water-to-ice phase transition on the properties of Lamb and quasi shear horizontal (QSH) acoustic waves of a higher order propagating in different directions in piezoelectric plates with strong anisotropy. Y-cut LiNbO3, 128Y-cut LiNbO3, and 36Y-cut LiTaO3 plates with a thickness of 500 μm and 350 μm were used as piezoelectric substrates. It was shown that the amplitude of the waves under study can decrease, increase, or remain relatively stable due to the water-to-ice phase transition, depending on the propagation direction and mode order. The greatest decrease in amplitude (42.1 dB) due to glaciation occurred for Lamb waves with a frequency of 40.53 MHz and propagating in the YX+30° LiNbO3 plate. The smallest change in the amplitude (0.9 dB) due to glaciation was observed for QSH waves at 56.5 MHz propagating in the YX+60° LiNbO3 plate. Additionally, it was also found that, in the YX+30° LiNbO3 plate, the water-to-ice transition results in the complete absorption of all acoustic waves within the specified frequency range (10-60 MHz), with the exception of one. The phase velocities, electromechanical coupling coefficients, elastic polarizations, and attenuation of the waves under study were calculated. The structures "air-piezoelectric plate-air", "air-piezoelectric plate-liquid", and "air-piezoelectric plate-ice" were considered. The results obtained can be used to develop methods for detecting ice formation and measuring its parameters.

Widespread loss of safe lake ice access in response to a warming climate.

Millions of people rely on lake ice for safe winter recreation. Warming air temperatures impact the phenology (timing of formation and breakup) and quality (ratio of black to white ice) of lake ice cover, both critical components of ice safety. Later formation and earlier breakup of lake ice lead to overall shorter periods of use. However, greater proportions of white ice may further inhibit safe ice use owing to its lower weight-bearing capacity. As ice cover duration decreases and ice quality changes in a warming world, the period of safe ice use will similarly diminish. We use a large ensemble modeling approach to predict ice safety throughout the winter period in the Northern Hemisphere. We used the Community Earth System Model Version 2 Large Ensemble (CESM2-LE) to calculate the period when ice first appears until it is of sufficient thickness for safe use, which depends on the ratio of black to white ice. We conducted this analysis for 2,379 to 2,829 ~1° by 1° grid cells throughout the Northern Hemisphere. We focus on the period between ice formation (≥ 2 cm) to a safe thickness for general human use (i.e., ≥10, ≥15, or ≥20 cm, depending on the ratio of black to white ice). We find that the transition period from unsafe to safe ice cover is growing longer, while the total duration of safe ice cover is getting shorter. The transition period of unsafe ice increases by 5.0 ± 3.7 days in a 4°C warmer world, assuming 100% black ice. Diminished ice quality further limits safe ice conditions. The unsafe transition period increases by an average of 19.8 ± 8.9 days and 8.8 ± 6.6 days for the ice formation and breakup periods, respectively in a 4°C warmer world assuming 100% white ice conditions. We show that although many lakes are forecasted to freeze, they will be unsafe to use for an average of 5 to 29 fewer days in a 4°C warmer world for 100% black and 100% white ice ratios, respectively. This wide range indicates that ice quality has a strong influence on ice safety. This work highlights the need to understand both lake ice phenology and quality to better assess safe lake ice use during the formation and melt periods.

Water content, fractional composition of water, carbohydrate and fatty acid composition of lipids in renewal buds of <I>Hylotelephium triphyllum</I> (Crassulaceae) during overwintering

Renewal buds are a good model for studying growth, metabolism and bioenergetics under the influence of environmental factors (light, temperature). Such studies can provide new information about physiological, biochemical and molecular mechanisms of shoot growth at the stage of growth inside the bud under the influence of exogenous and endogenous factors. The paper contains the data on seasonal changes in energy metabolism, fractional composition of water, content of photosynthetic pigments, soluble carbohydrates, protein, and fatty acids in renewal buds of Hylotelephium triphyllum (Haw.) Holub. In the renewal buds formed in August, the total water content is about 85%, the share of water passing into the crystalline state – more than 90%, the temperature of the water-to-ice phase transition – −6°C. The intensity of respiration decreases, and the rate of energy storage, accumulation of soluble carbohydrates and unsaturated fatty acids increases gradually against the high water content and high proportion of unbounded water in plant tissues as long as the average daily temperatures decrease. There is a direct relationship between the respiration intensity, heat release, and energy storage. During the autumn-winter-spring period, the proportion of stored energy from the energy produced by respiration is about 40%. The formation of the photosynthetic apparatus of renewal buds is accompanied by a decrease in the rate of heat release and in the amount of stored energy. The swelling of buds proceeds simultaneously with an increase in the content of fatty acids, which indicates the activation their synthesis and coincides with the spring maximum content of chlorophylls and carotenoids. At this period, the total water content is about 75%, the proportion of water passing into the crystalline state – about 99%. The temperature of the water-to-ice phase transition is −4.7°C. This temperature value of ice formation is probably the minimum possible temperature at which irreversible damages to cellular structures occur in renewal buds. Consequently, the high water saturation in renewal buds of Hylotelephium triphyllum maintains metabolic processes and, as a result, favors the implementation of morphophysiological and structural rearrangements in them but also significantly increases the risk of damage by negative temperatures in low-snow winters.