Ice Thermal Regime Research Articles

Владимир Михайлович Сокольников: жизнь на благо Родины и науки

The article is dedicated to the well-known hydrologist, meteorologist and hydrophysicist, glaciologist, polar explorer and Baikal scientist, candidate of technical sciences Vladimir Mikhailovich Sokolnikov (1904–1971). V.M. Sokolnikov is a major specialist in the ice-thermal regime of rivers and lakes. He is one of the organizers of ice crossings on Lake Ladoga during the Great Patriotic War (1941–1945). He was also a member of the first polar expeditions in the Arctic, the author of a number of works on the hydrological and ice regime of the rivers of the Leningrad Region, the Caucasus and the ice regime of Lake Baikal. In 1952 V.M. Sokolnikov came to Baikal. Here he created the Laboratory of Hydrology and Hydrophysics at the Baikal Limnological Station (later the Limnological Institute of the Siberian Branch of the Russian Academy of Sciences). He created the Baikal school of hydrology, which is currently developing the directions identified by V.M. Sokolnikov. Life of V.M. Sokolnikov – scientist, organizer of scientific research and teacher, is an example of selfless service to the Motherland and his cause. The article was prepared in connection with the 80th anniversary of the “Road of Life” on Lake Ladoga, in the construction of which V.M. Sokolnikov was directly involved.

Estimation of the Dependence of Ice Phenomena Trends on Air and Water Temperature in River

The identification of changes in the ice phenomena (IP) in rivers is a significant element of analyses of hydrological regime features, of the risk of occurrence of ice jam floods, and of the ecological effects of river icing (RI). The research here conducted aimed to estimate the temporal and spatial changes in the IP in a lowland river in the temperate climate (the Noteć River, Poland, Central Europe), depending on air temperature (TA) and water temperature (TW) during the multi-annual period of 1987–2013. Analyses were performed of IP change trends in three RI phases: freezing, when there appears stranded ice (SI), frazil ice (FI), or stranded ice with frazil ice (SI–FI); the phase of stable ice cover (IC) and floating ice (FoI); and the phase of stranded ice with floating ice (SI–FoI), frazil ice with floating ice (FI–FoI), and ice jams (IJs). Estimation of changes in IP in connection with TA and TW made use of the regression model for count data with a negative binomial distribution and of the zero-inflated negative binomial model. The analysis of the multi-annual change tendency of TA and TW utilized a non-parametric Mann–Kendall test for detecting monotonic trends with Yue–Pilon correction (MK–YP). Between two and seven types of IP were registered at individual water gauges, while differences were simultaneously demonstrated in their change trends over the researched period. The use of the Vuong test confirmed the greater effectiveness of estimates for the zero-inflated model than for the temporal trend model, thanks to which an increase in the probability of occurrence of the SI phenomenon in the immediate future was determined; this, together with FI, was found to be the most frequently occurring IP in rivers in the temperate climate. The models confirmed that TA is the best estimator for the evaluation of trends of the occurrence of IC. It was shown that the predictive strength of models increases when thermal conditions are taken into consideration, but it is not always statistically significant. In all probability, this points to the impact of local factors (changes in bed and valley morphology and anthropogenic pressure) that are active regardless of thermal conditions and modify the features of the thermal-ice regime of rivers at specific spatial locations. The results of research confirm the effectiveness of compilating a few models for the estimation of the dependence of IP trends on air and water temperature in a river.

Ice-thermal Regime of Lake Baikal under Conditions of Modern Warming (1950–2017)

The impact of modern climate change on lakes is one of the most relevant problems in the field of limnology. For Lake Baikal this impact is manifested in the change in abiotic characteristics of the lake ecosystem. It is shown that the pattern of modern climate change in the Baikal region includes both the “secular” warming trend and the intrasecular variations which exceed this trend in the scale and may be caused by atmospheric circulation. The effect of atmospheric circulation is associated with the physiographic characteristics of separate parts of the lake and its watershed. The influence of changes in atmospheric circulation on the ice and thermal regime of Lake Baikal is analyzed for the period of 1950–2017 for which objective analysis data on the large-scale atmospheric circulation in the Northern Hemisphere are available.

Effect of climate change on thermal-ice regime of shallow lakes compared to deep lakes: Case study of lakes in the temperate zone (Northern Poland)

The objective of this study is to determine the usefulness of results of hydrological observations (1961-2015) carried out in a deep lake for the assessment changes in the ice-thermal regime of a shallow lake. The paper is based on results of daily values of surface water temperature and ice phenomena in shallow Lake Łebsko and deep Lake Charzykowskie. Similar, statistically significant, positive trends of water temperature were determined in both lakes (0.26°C 10 year-1 in Lake Łebsko and 0.25°C 10 year-1 in Lake Charzykowskie). The fastest increase in mean monthly water temperature in the analysed period (1961-2015) occurred in May (3.37°C in Lake Charzykowskie) and April (2.76°C in Lake Łebsko). The majority of elements of the thermal regime of surface waters in shallow lakes were generally determined to be similar to the same elements in deep lakes, and the effect of climatic changes on the thermal regime of both lakes was found to be similar. Less similarity is observed between elements of the ice regime, particularly in date of decline of the ice cover.

Heat balance of Lake Baikal and the relationship of its ice-thermal and water regime with global atmospheric circulation in the Northern Hemisphere during the modern period

The article presents a summary of the most important results obtained during the studies of the heat balance at Lake Baikal since the 1930s. The systematic regime measurements of water temperature initiated in Limnological Institute since 1970 indicated the features of the spatial structure and temporal changes in the elements of the Baikal heat balance. We have determined the magnitude of the annual evaporation from the surface of Lake Baikal by the independent method considering the data on temperature of the water column. We have investigated one of the main renewal processes of deep and near-bottom Baikal waters associated with thermobaric effect. As a result of this effect, the water renewal and aeration in the near-bottom layer annually occurs under certain hydrological conditions. We have determined the vertical flows of mass, heat and gas exchange of the upper and deep layers in Lake Baikal. We have studied the effect of changes in the characteristics (indices) of the atmospheric circulation in the Northern Hemisphere on the variability of the characteristics of climate and ice-thermal regime at Baikal, i.e. air temperature and water surface temperature, ice thickness, as well as dates of ice phenomena during the modern period. Anomalies of the atmospheric circulation are most obvious in the ice processes. We have found the relationship between the water temperature of the warm (May-September) period and the indicators of the zonal circulation (positive relationship), as well as indices of the formations blocking the western transfer (negative relationship). There is an obvious effect on the water surface temperature of the winter circulation indices. We have shown that these changes are associated with the fluctuations in the intensity of the zonal circulation and the baric formations blocking them. There is the effect of circulation on the moisture characteristics (precipitation and runoff), but it is complicated by large differences in climate within the Baikal catchment area.

Effects of dam reconstruction on thermal-ice regime of Fengman Reservoir

A laterally-averaged 2D water temperature model coupled with an ice cover module was used to investigate the influences of the Fengman Dam reconstruction on its thermal regime. Variations of the thermal-ice regime and outflow temperature under typical hydro-metrological conditions were simulated and validated with field data. Due to the partial dismantling of the old dam after the reconstruction, the intake water is primarily taken from the surface layer of the reservoir. As a result, the total heat storage of the reservoir throughout the year and the outflow temperature from January to March will decrease. Furthermore, the low outflow temperature in the winter will result in a decline of the downstream water temperature and negatively impact the rime scenery near Jilin City. In order to increase the outflow temperature in winter, an operation scheme that combined the new intake with the old intake of the III-phase project of old dam was discussed. The results indicated that this scheme could increase the outflow temperature to ensure a 70km open channel in the downstream river in a typical winter, and eliminated the negative effects on the rime scenery.

Effect of climatic changes on the development of the thermal-ice regime based on the example of Lake Charzykowskie (Poland)

Abstract. The paper discusses the course of air temperature in the years 1961-2014 in Chojnice (Central European Lowland), and its effect on water temperature and occurrence of ice cover on Lake Charzykowskie. An increase in mean annual air temperature was determined by 0.31 o C per 10 years, and its even faster increase in the winter season (December-March), by 0.37 o C per 10 years on average. An increase in mean annual water temperature in the lake by 0.24 o C per 10 years also occurred. An increase in air and water temperature in winter months caused a reduction of the period of occurrence of ice cover. In the years 1961-2014, the persistence of ice cover was subject to a decrease by 3.7 days per 10 years on average, and the mean thickness of the ice cover decreased from 30 to 19 cm.

Effect of climatic changes on the development of the thermal-ice regime based on the example of Lake Charzykowskie (Poland)

Abstract The paper discusses the course of air temperature in the years 1961-2014 in Chojnice (Central European Lowland), and its effect on water temperature and occurrence of ice cover on Lake Charzykowskie. An increase in mean annual air temperature was determined by 0.31°C per 10 years, and its even faster increase in the winter season (December-March), by 0.37°C per 10 years on average. An increase in mean annual water temperature in the lake by 0.24°C per 10 years also occurred. An increase in air and water temperature in winter months caused a reduction of the period of occurrence of ice cover. In the years 1961-2014, the persistence of ice cover was subject to a decrease by 3.7 days per 10 years on average, and the mean thickness of the ice cover decreased from 30 to 19 cm.

Ice thermal regime of the lower pool of the Novosibirsk hydraulic power system

A model of unsteady-state hydrodynamic and ice-thermal processes has been constructed for studying the problem of optimization of water releases into the lower pool of the Novosibirsk Hydropower System in winter. The results of calculations have been used to determine the ice-induced backwater effect on the level of free surface of water flow at the section of the main water intake for Novosibirsk City. Comparative analysis of computer modeling results and field data has been carried out. The results of numerical calculations of ice cover dynamics in the lower pool of the Novosibirsk HPP were shown to serve as a basis for substantiating the regime of releases made to ensure stable functioning of river water intakes near Novosibirsk C. in winter seasons of low-water years.

The results of the numerical simulation of regime variations in the Mozhaisk and Istra reservoirs for the A2 scenario of global warming

Presented are the results of computation of variations of hydrological characteristics in the reservoirs of different types of the Moscow River water system in the case of the predicted global warming (variations of flowage, of ice thermal regime, and stratification of water column) at the realization of the most adverse scenario for the Moscow water supply consisting in the reduction of the annual runoff layer and the runoff layer during the high-water period.

Dependence of century-scale projections of the Greenland ice sheet on its thermal regime

AbstractObservations show that the Greenland ice sheet has been losing mass at an increasing rate over the past few decades, which makes it a major contributor to sea-level rise. Here we use a three-dimensional higher-order ice-flow model, adaptive mesh refinement and inverse methods to accurately reproduce the present-day ice flow of the Greenland ice sheet. We investigate the effect of the ice thermal regime on (1) basal sliding inversion and (2) projections over the next 100 years. We show that steady-state temperatures based on present-day conditions allow a reasonable representation of the thermal regime and that both basal conditions and century-scale projections are weakly sensitive to small changes in the initial temperature field, compared with changes in atmospheric conditions or basal sliding. We conclude that although more englacial temperature measurements should be acquired to validate the models, and a better estimation of geothermal heat flux is needed, it is reasonable to use steady-state temperature profiles for short-term projections, as external forcings remain the main drivers of the changes occurring in Greenland.

Northern sector of the Uummannaq Ice Stream System, West Greenland – Deglacial behaviour and Holocene climatic variability

Glacial bedform patterns and sediments deposited by the temperate and polythermal Late Devensian ice sheet in north-central Ireland record changes in the processes, location, and magnitude of subglacial meltwater throughout the last full glacial cycle (∼21–14 14C kyear BP). Meltwater characteristics are related directly to basal ice thermal regime and ice dynamics, including ice velocity and shifts in the location of ice centres. Therefore, reconstructed meltwater characteristics may provide insight into wider controls on dynamic ice behaviour. A range of meltwater-related features are present across north-central Ireland. These include tunnel valleys, drumlin leeside sequences, eskers, and boulder lags. Other bedforms including Rogen moraines were modified by meltwater activity along ice streams. Meltwater was stored subglacially in two contrasting regions located beneath or near ice centres in north-central Ireland. (1) The Lough Erne Basin is developed in a lowland depression occupied partly by subglacial Rogen moraine ridges which were formed around the time of the last glacial maximum. Meltwater was stored between Rogen ridge crests and released by hydraulic jacking associated with drumlinisation (∼16.6 14C kyear BP) and ice streaming (∼13.8 14C kyear BP). (2) The Lough Neagh Basin occupies a similar lowland depression and was the location of an ice sheet centre throughout the last glacial cycle. No bedforms are present beneath or immediately surrounding Lough Neagh. A larger, more continuous meltwater lake existed in the Lough Neagh depression, probably sealed by a region of cold-based ice outside lake margins. Water escaped through regional-scale tunnel valleys, particularly the Poyntzpass channel which was active during the Carlingford ice readvance (Killard Stadial, correlated with Heinrich event 1 at ∼14.5 14C kyear BP). Overall, reconstructed subglacial lake characteristics and drainage mechanisms are related closely to basal ice thermal regime and substrate relief (controlling lake geometry), and provide insight into controls on overall ice sheet dynamics.

Sedimentary evidence for the formation mechanism of the Armoy moraine and late Devensian glacial events in the north of Ireland

AbstractThe internal sedimentology of the Armoy moraine, which marks a late Devensian (Weichselian) incursion of Scottish ice into the north of Ireland, is described from a temporary exposure near Armoy village. The exposure (up to 30 m long, 10 m high) comprises folded gravel beds, massive clay grading up to pebbly diamicton, massive gravel, overfolded and deformed sand, and a gravel and massive diamicton cover. These sediments overlie glacially smoothed basalt bedrock. The sediment succession records the interaction of near‐touching Scottish and Irish ice margins, and the formation, infilling and drainage of an ice‐supported proglacial lake. Scottish ice likely advanced into the north of Ireland by a short‐lived glacier surge during the Killard Point Stadial (coeval with Heinrich Event 1 at 14.5 14C ka BP), forming the Armoy moraine at its maximum extent. The presence of rafted sediment blocks within the moraine suggests ice‐marginal thrusting and deformation of proglacial sands, and syntectonic resedimentation into low points on the sediment surface. Asynchroneity between Scottish and Irish ice‐marginal fluctuations may reflect differing responses to climate forcing during the Killard Point Stadial, or the effects of local factors such as substrate type and basal ice thermal regime. Copyright © 2004 John Wiley & Sons, Ltd.

Seasonal development of the properties and composition of landfast sea ice in the Gulf of Finland, the Baltic Sea

The seasonal development of the structure, salinity, and stable oxygen isotopic composition (δ18O) of landfast sea ice was studied during the winter seasons 1999–2001 in the Gulf of Finland in the Baltic Sea. The main focuses were on the seasonal and the interannual variability in ice properties and composition and on the contribution of meteoric ice to sea ice mass balance. Results provide a first statistical description of the seasonal evolution of sea ice in mild ice climate conditions. The ice has a characteristic structure with an upper granular ice layer, composed almost exclusively of superimposed ice and snow‐ice, averaging at 20–35% of the total ice thickness. The remaining is composed of columnar or intermediate granular columnar ice, depending on growth conditions. While salinity shows a uniform profile through the ice, δ18O shows lower values in the surface because of meteoric ice formation. The thin ice cover is susceptible to changes in atmospheric conditions, and rapid changes in ice salinity are connected to changes in the ice thermal regime and flooding. The contribution of meteoric ice varied from 0 to 35% (by mass), depending on season and year. Superimposed ice formation is a recurring process and significantly contributed to ice growth (up to 20% by mass), especially late in the season during snowmelt‐freeze cycles. Liquid precipitation also cause formation of intermittent superimposed ice layers at these latitudes. The contribution of meteoric ice to sea ice mass balance is largely dependent on the amount and timing of snow accumulation and timing of snowmelt‐freeze processes, which all showed large year‐to‐year variation. The conditions presented here may start to occur at higher latitudes if global warming continues.

Bedform patterns, subglacial meltwater events, and Late Devensian ice sheet dynamics in north-central Ireland

Glacial bedform patterns and sediments deposited by the temperate and polythermal Late Devensian ice sheet in north-central Ireland record changes in the processes, location, and magnitude of subglacial meltwater throughout the last full glacial cycle (∼21–14 14C kyear BP). Meltwater characteristics are related directly to basal ice thermal regime and ice dynamics, including ice velocity and shifts in the location of ice centres. Therefore, reconstructed meltwater characteristics may provide insight into wider controls on dynamic ice behaviour. A range of meltwater-related features are present across north-central Ireland. These include tunnel valleys, drumlin leeside sequences, eskers, and boulder lags. Other bedforms including Rogen moraines were modified by meltwater activity along ice streams. Meltwater was stored subglacially in two contrasting regions located beneath or near ice centres in north-central Ireland. (1) The Lough Erne Basin is developed in a lowland depression occupied partly by subglacial Rogen moraine ridges which were formed around the time of the last glacial maximum. Meltwater was stored between Rogen ridge crests and released by hydraulic jacking associated with drumlinisation (∼16.6 14C kyear BP) and ice streaming (∼13.8 14C kyear BP). (2) The Lough Neagh Basin occupies a similar lowland depression and was the location of an ice sheet centre throughout the last glacial cycle. No bedforms are present beneath or immediately surrounding Lough Neagh. A larger, more continuous meltwater lake existed in the Lough Neagh depression, probably sealed by a region of cold-based ice outside lake margins. Water escaped through regional-scale tunnel valleys, particularly the Poyntzpass channel which was active during the Carlingford ice readvance (Killard Stadial, correlated with Heinrich event 1 at ∼14.5 14C kyear BP). Overall, reconstructed subglacial lake characteristics and drainage mechanisms are related closely to basal ice thermal regime and substrate relief (controlling lake geometry), and provide insight into controls on overall ice sheet dynamics.

Thermal Regime of Ice Covered Swedish Lakes

Temperature conditions and heat fluxes in ice covered lakes are discussed analyzing measurements in eight Swedish lakes. Heat fluxes from sediments and heat fluxes from water to ice are determined from temperature profiles. The contribution of solar radiation is estimated from heat-budget calculations. It is found that the heat content of most of the lakes changes very little when they are ice covered, but that the lake-water temperature slightly increases. All heat fluxes are small. The heat flux from the sediments is the highest flux in early winter, but is later in the winter balanced by the heat loss from the water to the underside of the ice. Solar radiation is an important heat source in late winter, when the snow cover is thin.

Sediment-mass exchange between turbid meltwater streams and proglacial deposits of storglaciären, northern Sweden

Detailed changes in surface elevation of a recently deglaciated area have been mapped using a high-resolution photogrammetric method, with a view to estimating the contribution of debris from the proglacial area to the meltwater streams draining Storglaciären, northern Sweden, over the period 1980-90. The net contribution of sediments originating from the deglaciated area immediately in front of the glacier was of the order of 50% of the suspended silt load transported by meltwater at the flume Rännan downstream from the glacier, but at the same time, a similar amount of sediment accumulated along the streams. Though there is a significant exchange of mass, the net change is close to zero. Moreover, the survey provides detailed information about morphological changes in the landscape. Different processes, such as melting of permafrost, fluvial erosion and sedimentation, have been active.Erosion and sedimentation rates were calculated from the difference between digital terrain models based on aerial photographs taken in 1980 and 1990. The result shows erosion in the central part of the proglacial area and accumulation of coarser sediments along the braided streams. In places, the ground is sinking, possibly due to melting of permafrost.Where the ice is thinner, in the marginal zone, the thermal regime of ice in the tongue of Storglaciären corresponds well with the proglacial geomorphology. At present, the glacier has a 30-40 m thick cold surface layer which at the thinner marginal zone corresponds to a 100-200 m wide frozen rim. The temperature distribution within the ice was mapped using high-resolution radar.

Sediment-mass exchange between turbid meltwater streams and proglacial deposits of storglaciären, northern Sweden

Detailed changes in surface elevation of a recently deglaciated area have been mapped using a high-resolution photogrammetric method, with a view to estimating the contribution of debris from the proglacial area to the meltwater streams draining Storglaciären, northern Sweden, over the period 1980-90. The net contribution of sediments originating from the deglaciated area immediately in front of the glacier was of the order of 50% of the suspended silt load transported by meltwater at the flume Rännan downstream from the glacier, but at the same time, a similar amount of sediment accumulated along the streams. Though there is a significant exchange of mass, the net change is close to zero. Moreover, the survey provides detailed information about morphological changes in the landscape. Different processes, such as melting of permafrost, fluvial erosion and sedimentation, have been active.Erosion and sedimentation rates were calculated from the difference between digital terrain models based on aerial photographs taken in 1980 and 1990. The result shows erosion in the central part of the proglacial area and accumulation of coarser sediments along the braided streams. In places, the ground is sinking, possibly due to melting of permafrost.Where the ice is thinner, in the marginal zone, the thermal regime of ice in the tongue of Storglaciären corresponds well with the proglacial geomorphology. At present, the glacier has a 30-40 m thick cold surface layer which at the thinner marginal zone corresponds to a 100-200 m wide frozen rim. The temperature distribution within the ice was mapped using high-resolution radar.

Ice-thermal regime of the Angara river at the construction site of the Ust'-Ilimsk hydroelectric station

Ice-thermal regime of the Angara river at the construction site of the Ust'-Ilimsk hydroelectric station

Change of the ice-thermal regime of the lower Volga in connection with construction of the Volga hydroelectric station (named for the XXII congress of the CPSU) and formation of the Volgograd reservoir

Change of the ice-thermal regime of the lower Volga in connection with construction of the Volga hydroelectric station (named for the XXII congress of the CPSU) and formation of the Volgograd reservoir