Cold Climate Zones Research Articles

Nonlinear response of vegetation green-up to local temperature variations in temperate and boreal forests in the Northern Hemisphere

The annual cycle of vegetation growth may be altered in response to climate changes affecting ecosystem dynamics. However, our understanding of vegetation seasonality is mostly limited to the mechanisms and attributes of phenological events, such as spring emergence and fall senescence. Here we have investigated the seasonal evolution of vegetation growth from winter dormancy to summer maturity of four forest types in the Northern Hemisphere (NH) temperate and boreal forests for 1982–2011. The present study assesses large-scale variations in the vegetation green-up rate (VGrate) and its connection to temperature variability using remotely sensed normalized difference vegetation index (NDVI) and surface air temperature. The average of the VGrate of the analysis period increases with latitude, which indicates that the canopy develops more rapidly from dormancy to maturity for vegetation in higher-latitude or colder climate zones. VGrate and precedent temperature also show a positive correlation (r) over temperate and boreal forests (67% of the forest area in the NH), indicating that increased temperatures lead to faster canopy development within the same climate zone or latitude band. Responsiveness of VGrate to temperature variability shows that despite the same magnitude of local temperature variability during extremely cold and warm years, the magnitude of VGrate acceleration in warm years (0.07 (15-day)−1) is larger than the VGrate deceleration in cold years (−0.03 (15-day)−1), suggesting that the response of VGrate to temperature variability is nonlinear. Among the four forest types examined in this study, the nonlinear responses are most clearly observed in deciduous broadleaf forests indicating that forest composition may regulate the large-scale response of canopy development to temperature variability. Overall, our results suggest that anomalous seasonal warming will significantly affect canopy developments over wide deciduous forest areas.

Correlation analysis of building plane and energy consumption of high-rise office building in cold zone of China

With the rapid growth of high-rise office buildings in China, the huge energy consumption of these buildings has become a concern recently. While much research is focused on the HVAC system efficiency, there is little study on the association between building plane and energy consumption from the perspective of passive building design priority. In this study, 8 cases of typical high-rise office building plane in 6 categories are established in the city of Beijing, which is located in cold climate zone of China, and the annual dynamic load and energy consumption are calculated using the Design Builder software. The correlation between plane and energy consumption was studied based on the analysis of several key related factors. They are functional area ratio, shape coefficient, plane functional depth, traffic space arrangement, large atrium and natural lighting. The results show that, compared to total floor area, energy consumption per functional area is a more applicable index to evaluate building plane efficiency and energy consumption level across different design schemes. Influences of shape coefficient on energy consumption are mainly in envelope load. Compared with building depth, functional depth has a higher correlation with energy consumption. It is positively correlated with lighting energy consumption, and negatively correlated with envelope load. Traffic space arrangement mainly affects lighting, solar heat gain and envelope load, while its influences on total energy consumption need to be considered comprehensively. Our simulation results show that the differences of energy consumption across all the cases can be up to 17%, and a linear plane with a traffic space arranged in the north has the lowest energy consumption.

Influence of the regulation framework on the feasibility of a Stirling engine-based residential micro-CHP installation

In this paper an economic analysis of a 1 kWe Stirling engine-based micro-CHP (combined heat and power) residential plant is developed, approaching the case of a Spanish detached house sited in a cold climatic zone. The work focuses on analysing how the latest modifications in the Spanish micro-CHP and renewable energies regulation affect viability of this technology, as well as predicting what results could be achieved if policy support mechanisms in Spain were like those in two other European countries, Germany and United Kingdom, where this kind of equipment has good acceptance.For that purpose, once defined the reference dwelling, with the consequent consumption patterns, an installation for covering heating and DHW (domestic hot water) demands of the building, as well as part of the electric load, is designed and simulated in TRNSYS 17, getting results of those performance parameters necessary for applying the economic analysis. A condensing boiler supported by solar thermal collectors is taken as the reference installation. Results show that pay-back conditions of this kind of installations have turned hardly achievable with new remunerative conditions, getting widely better results with economic frameworks of other European countries.

Ethological-physiological effects of hypoxia on the honeybee Apis mellifera L.

Information on the effect of hypoxia on the behavior and physiological state of the honeybee was compiled and systematized. It was shown that, in the course of colonization of temperate and cold climate zones by the honeybee, natural selection favored the acquisition of an effective mechanism of thermoregulation and high tolerance to hypoxia. It was noted that bees can develop under conditions when the CO2 concentration exceeds the content of this gas in the surface layer of the Earth by more than three orders of magnitude; however, this leads to deviations in the morphometric traits from the norm. At the adult stage, anesthesia with carbon dioxide was found to reduce the body weight and the water content in it. It was shown that the effect of anesthesia in adult bees increases with temperature and that hypoxia in adult bees and queens accelerates their senescence and reduces viability.

Climate-Sensitive Urban Design in Cold Climate Zone: The City of Erzurum, Turkey

The main objective of this paper is to explore the contradictory relationship between the climate and physical structure of the built environment in Erzurum as one of the coldest climate cities in Turkey. It mainly questions whether the urban form and geometry (size, density, street orientation and ventilation), height and shape of the buildings and vegetation in selected districts of Erzurum are compatible with the cold climate conditions. In this direction, disturbances, vulnerability of urban ecosystem, construction practices, street orientations, settlement patterns, housing typology, density, average height, hard-surfaces, distances, flora and density of green areas are analyzed. The findings show that the urban built environment in Erzurum (City Centre, Dadaskent and Yildizkent districts) is not consistent with the cold climate conditions. Urban heat island, urban sprawl, ventilation problems and existing air pollution, and high temperature differences in the city are the threatening factors for ecologically sustainable urban development. In the context of this study, it is aimed to formulate urban design guidelines for the city of Erzurum in cold climate zone. Urbanization and urban form of the three different districts, which are the focus areas of this research, must be reconsidered from a climate sensitive perspective, otherwise new development areas will not be energy efficient and resilient against changes, surprises and risks. For ecologically sustainable urban development, climate sensitive urban design guidelines must urgently be prepared and implemented for Erzurum.

Regional features of the bioclimate of Central and Southern Europe against the background of the Köppen-Geiger climate classification

Climate Index UTCI to studies of regional variability in human-biometeorological conditions. The variability in question was assessed by reference to selected meteorological stations representing Central and Southern Europe, i.e. Kolobrzeg, Warsaw and Świeradow (in Poland), Prague, Budapest, Ljubljana, Milan, Rome and Athens, with the bioclimatic features characterising these localities being presented against the background of the Koppen-Geiger climate classification. In line with that classification, the first five stations are found to represent the cold climate zones (Dfb, Dfc). The last four stations are in turn located in the temperate climate zones (Cfa, Cfb, Csa). Seasonal changes in UTCI values and the frequency of occurrence of UTCI categories are discussed. Significant regional differences in bioclimatic characteristics were found between the stations representing various types of climate. While the highest summer values for UTCI are very similar at all stations (39-42°C), the frequency of occurrence of days with at least strong heat stress (SHS) varied from 2% at the coastal station of Kolobrzeg in Poland to more than 50% at the Milan, Rome and Athens stations. In winter the lowest UTCI values are much differentiated regionally, from -54°C at the mountain station in Świeradow, Poland, to -22°C in Rome. In the zone of cold climate, the frequency of occurrence of days with at least strong cold stress (SCS) is >40%, while in the temperate climates, strong cold stress is characteristic of less than 2% of winter days.

Book Review: Gąsiewicz, A. and Słowakiewicz, M. 2013. Palaeozoic Climate Cycles: Their Evolutionary and Sedimentological Impact. Geological Society Special Publication, 376, 1-586. The Geological Society London.

Book Review: Gąsiewicz, A. and Słowakiewicz, M. 2013. Palaeozoic Climate Cycles: Their Evolutionary and Sedimentological Impact. Geological Society Special Publication, 376, 1-586. The Geological Society London.

Estimation of degree-days for different climatic zones of North-East India

Efficient use of energy in buildings has become a necessity due to increasing heating and cooling energy demand. Degree-days are a versatile climatic indicator that can be used to estimate the heating and cooling energy requirement for a building. In this study, heating degree-days (HDD) and cooling degree-days (CDD) are estimated for warm and humid, cool and humid and cold and cloudy climatic zones of North-East India. The daily maximum and minimum temperature data are collected from Regional Meteorological Centre, Guwahati. The degree-days are calculated by using three different methods, i.e. ASHRAE formula, UKMO equations and Schoenau–Kehrig method for different base temperatures. It has been found that there is a variation in degree-days obtained from the above methods in the respective climatic zone and also varies from zone to zone. The degree-days are also estimated on hourly basis based on Typical Meteorological Year (TMY) data for validation. Generalized equations are developed by using multiple linear regression technique to estimate the degree-days and those satisfied the statistical tests are proposed. The developed equations can be used to obtain degree-days of locations in same climatic zone for which daily temperature data are not available, with a fair accuracy.

Streamflow simulation methods for ungauged and poorly gauged watersheds

Abstract. Rainfall–runoff modelling procedures for ungauged and poorly gauged watersheds are developed in this study. A well-established hydrological model, the University of British Columbia (UBC) watershed model, is selected and applied in five different river basins located in Canada, Cyprus, and Pakistan. Catchments from cold, temperate, continental, and semiarid climate zones are included to demonstrate the procedures developed. Two methodologies for streamflow modelling are proposed and analysed. The first method uses the UBC watershed model with a universal set of parameters for water allocation and flow routing, and precipitation gradients estimated from the available annual precipitation data as well as from regional information on the distribution of orographic precipitation. This method is proposed for watersheds without streamflow gauge data and limited meteorological station data. The second hybrid method proposes the coupling of UBC watershed model with artificial neural networks (ANNs) and is intended for use in poorly gauged watersheds which have limited streamflow measurements. The two proposed methods have been applied to five mountainous watersheds with largely varying climatic, physiographic, and hydrological characteristics. The evaluation of the applied methods is based on the combination of graphical results, statistical evaluation metrics, and normalized goodness-of-fit statistics. The results show that the first method satisfactorily simulates the observed hydrograph assuming that the basins are ungauged. When limited streamflow measurements are available, the coupling of ANNs with the regional, non-calibrated UBC flow model components is considered a successful alternative method to the conventional calibration of a hydrological model based on the evaluation criteria employed for streamflow modelling and flood frequency estimation.

Waste Heat Recovery Systems of Shampoo Drain Water from Barbershops

Two waste heat recovery systems of barbershops were presented to increase its heat utilization efficiency. One was the waste heat recovery system with water-to-water heat exchanger (WHR-HE). The other is the waste heat recovery system with both water-to-water heat exchanger and heat pump (WHR-HE-HP). The two waste heat recovery systems were analyzed by both economics and thermodynamics principles. Compared to conventional heat utilization systems of barbershops, the WHR-HE decreases annual energy consumption by 54.2%, and the WHR-HE-HP decreases annual energy consumption by 87.5%. The gain investment recovery periods of WHR-HE and WHR-HE-HP are below half one year. Compared to the WHR-HE, the WHR-HE-HP is with larger energy-saving potential, lower running cost, larger first cost and larger gain investment recovery period. The critical value of energy-saving financial subsidy is 0.778 ¥/W for the WHR-HE-HP. The WHR-HE-HP is very suited to the large and medium-sized barbershops, especially in the cold climate zone.

A Comparison of the Views of Ibn Khaldun and Montesquieu in Terms of the Effect of Climatic Conditions on Human Life

There is a significant similarity between Ibn Khaldun, having lived in the Northern Africa in the fourteenth century and Montesquieu in terms of their ideas concerning the direct effect of geographical conditions and climate on human life. According to Ibn Khaldun, who divided the world into seven climatic regions from the south to the north, the fourth climatic zone located just in the centre is the most suitable place to live. The moralities and personality features of the people living in these regions are more moderate compared to other regions. Similarly, Montesquieu indicated that climate has an effect on the personalities, behavioural forms of people and the laws they enact. According to him, those living in the cold climatic zones are coldblooded, proud and keen on their security and freedom. As for the ones living temperate zones, it changes. In this study, the ideas of the two thinkers suggesting that natural conditions have an effect on people and communities were compared.

Urban heat island effect on energy application studies of office buildings

Because of the urban heat island (UHI) effect a metropolitan area is typically warmer than its surrounding rural area. This has led to a growing concern that the use of standard (mostly rural) weather data leads to inadequate decision-making with regard to the energy efficiency of buildings in metropolitan areas. This paper conducts a series of computational studies that explore the UHI effect on two routine applications of building energy simulation: (1) predicting the magnitude of energy use and (2) predicting energy savings. We present the results based on case studies of office buildings in 15 representative cities across different climate zones in the U.S. The results show that the UHI considerably modifies the urban climate measured by cooling and heating degree days. As a consequence, ignorance of the UHI effect remarkably underestimates building total energy use in hot climate zones where cooling energy use is dominant, yet causes overestimation in cold climate zones where heating energy use is prevalent. In mild climate zones, the UHI effect only has a moderate effect because the effects on cooling and heating mostly average out. When building simulation is used to assess energy savings that is measured as the ratio to the corresponding baseline such as in a comparative analysis of retrofit measures, the UHI effect is less of a factor.

Air heating of passive houses in cold climates: Investigation using detailed dynamic simulations

The passive house (PH) standard was originally defined for Central Europe and has subsequently been applied to many cold climate countries. In these conditions, the relation between this standard and the air heating (AH) is not clear while both concepts are usually associated. Furthermore, the AH provides a way to simplify the space-heating distribution system. The present contribution investigates the feasibility of the AH concept in PH along with its challenges in terms of thermal dynamics: the magnitude of the AH temperature needed, the temperature difference between rooms, the impact of internal gains, the influence of thermal losses from ventilation ducts and the AH control. This is performed using detailed dynamic simulations (TRNSYS) on a typical detached house typology. Practically, four cold climate zones are considered as well as different insulation levels and construction materials. Results show limitations related to a centralized AH as well as provide guidelines for a consistent AH design in cold climates. In addition, a simple analytical method used for the design of German PH is tested and proved accurate enough to estimate the maximal AH temperature during the heating season.

Comparing large number of metaheuristics for artificial neural networks training to predict water temperature in a natural river

Nature-inspired metaheuristics found various applications in different fields of science, including the problem of artificial neural networks (ANN) training. However, very versatile opinions regarding the performance of metaheuristics applied to ANN training may be found in the literature.Both nature-inspired metaheuristics and ANNs are widely applied to various geophysical and environmental problems. Among them the water temperature forecasting in a natural river, especially in colder climate zones where the seasonality plays important role, is of great importance, as water temperature has strong impact on aquatic life and chemistry. As the impact of possible future climate change on water temperature is not trivial, models are needed to allow projection of streamwater temperature based on simple hydro-meteorological variables.In this paper the detailed comparison of the performance of nature-inspired optimization methods and Levenberg–Marquardt (LM) algorithm in ANNs training is performed, based on the case study of water temperature forecasting in a natural stream, namely Biala Tarnowska river in southern Poland. Over 50 variants of 22 various metaheuristics, including a large number of Differential Evolution, as well as some Particle Swarm Optimization, Evolution Strategies, multialgorithms and Direct Search methods are compared with LM algorithm on ANN training for the described case study. The impact of population size and some control parameters of particular metaheuristics on the ANN training performance are verified. It is found that despite widely claimed large improvement in nature-inspired methods during last years, the vast majority of them are still outperformed by LM algorithm on the selected problem. The only methods that, based on this case study, seem competitive to LM algorithm in terms of the final performance (but not speed) are Differential Evolution algorithms that benefit from the concept of Global and Local neighborhood-based mutation operators. The streamwater forecasting performance of the neural networks is adequate, the major prediction errors are related to the river freezing and melting processes that occur during winter in the mountainous catchment under study.

Geographic Variation in Air Temperature Leads to Intraspecific Variability in the Behavior and Productivity of a Eusocial Insect

In primitively eusocial insects, air temperature is the environmental factor that primarily affects colony cycle. Several studies demonstrated interspecific differences in the adaptation of eusocial insects to local air temperature. Nevertheless, studies on intraspecific adaptations are rare. In this study, we investigate the influence of air temperature on local adaptations in behavior and colony productivity of Polistes biglumis foundresses living in warm and cold temperate zones. We hypothesized that foundresses from warm temperate zones would show a higher activity level compared to those from cold temperate zones before brood emergence, based on differences in air temperature between the two zones. After brood emergence, we expected a reduced foundress activity level in the warm climate zone, due to workers’ help. In contrast, foundresses living in the cold-climate zone, which do not produce workers, were expected to remain active throughout the nesting season. We also hypothesized that colony productivity was higher in warm-climate colonies. As expected, warm-climate foundresses reduced their activity level after brood emergence and, with their relatively large number of workers, continued egg production throughout the nesting season. Further studies are necessary to assess if these intraspecific differences are attributable to phenotypic plasticity or genetic divergence.

Using dynamic model for determination of heat losses in cold weather from a typical house in Tabriz constructed by lightweight concrete blocks

Lightweight aggregate concrete blocks are being increasingly demanded for construction purposes. These materials, whose principal purpose of their use is to retard the flow of heat, have many other important benefits over normal concrete blocks. Some of these benefits consist of less dead weight of structure, fire resistance, and more endurance against weathering conditions of the environment; therefore, due to high thermal resistance of them, there is a growing tendency in their use in many cold climate zones, especially in earthquake-prone areas. To describe thermal phenomenon through the walls, dynamic thermal circuit modeling was applied in this process. Heat-insulating properties of lightweight concrete blocks were studied by means of thermal resistance parameter. Thermal mass, as another parameter, was investigated for energy-efficient building design. The conduction, convection, and radiation of heat transfer phenomena are being taken into account in this investigation. The abundance of volcanic pumice in the East Azarbaijan Province of Iran is believed to be a remarkable source of lightweight material to produce lightweight aggregate concrete blocks sized 0.2 m × 0.2 m (variable) × 0.4 m, with two equal cavities. East Azarbaijan with its harsh winter weathering conditions was selected for practical data inputs. To obtain realistic results, a typical house of 100 m2 in area was chosen for heat loss calculation and economic studies. Ratio of heat loss through external walls constructed with lightweight aggregate concrete blocks to that of the ones using normal concrete blocks for the same condition would be less than 0.35 that shows high potential of energy saving for heating. Furthermore, during a winter month, gas consumption, CO2 emission, and living expenses could be decreased as much as 700 kg, 1,925 kg, 625,990 IRR, respectively. Therefore, using lightweight concrete could be economically beneficial, environmentally favorable, and suitable for earthquake-prone areas.

Potential application of glazed transpired collectors to space heating in cold climates

Although unglazed transpired collectors (UTC) succeed in industrial ventilation applications, solar fraction is very low when they are used in space heating in cold climates due to the lower exit air temperature. Considering the potential for glazed transpired collectors (GTC) using recirculated air for space heating applications in cold climates, a mathematical model is developed for predicting the thermal performance of GTC. Simulation results show that although glazing results in optical loss, it could decrease convective heat loss resulted from high crosswind velocities effectively. For a solar radiation of 400W/m2, an ambient temperature of −10°C, and a suction velocity of 0.01m/s, the exit air temperature of GTC is higher than that of UTC for crosswind velocities exceeding 3.0m/s. By comparison with a conventional flat-plate solar air collector operating under the same conditions, the thermal performance of GTC shows a significant improvement. For a five-storey hotel building located in the severe cold climate zone of China, case study shows that the annual solar fraction of the GTC-based solar air heating system is about 20%, which is two times higher than that of the flat-plate collector-based system and nearly nine times higher than that of the UTC-based system respectively. Hence, an enormous amount of energy will be saved with the application of GTC to space heating in cold climates.

Dating the Trollesgave site and the Bromme culture – chronological fix-points for the Lateglacial settlement of Southern Scandinavia

The Bromme culture belongs to the Lateglacial, the period when people settled in the recently deglaciated Southern Scandinavia. Until now there have been only a few imprecise fix-points relating to the chronological position of this archaeological culture. This situation can now be improved with the aid of research results from a Bromme culture settlement at Trollesgave in SE Denmark. Using pollen and plant macrofossil data, Lateglacial lacustrine deposits containing waste material from the settlement can be assigned to the end of the climatically mild Allerød period. A series of 14C dates establishes the age of the settlement as c. 10 826 ± 49 14C years BP (12 871–12 590 cal yr BP). By correlation with climate data from the Greenland ice cores, the occupation can be assigned to the early part of the cold climatic zone GS-1, thus demonstrating that the global ice-core climate zones are not absolutely synchronous with the regional division into biozones.

Experimental study of a building-integrated solar air heating system in cold climate of China

A series of experiments were carried out in Harbin, a typical city of the severe cold climate zone of China under real transient outdoor conditions to investigate thermal performance, color effect and energy savings of a building-integrated solar air heating system based on unglazed transpired collectors (UTCs). The average efficiency of black UTC was 77.64% and 68.92% under high and low air flow rate respectively, which are higher than most glazed flat-plate collectors. Collector's surface color had an effect on its thermal performance. However, the thermal efficiency of colored UTC was still competitive, and therefore it is feasible to use colored UTC on building façade for esthetic reasons. Design heating load of a reference building in Harbin can be reduced by 6.4% due to reduced wall loss with the application of UTC. For a first cost less than 200$/m2, it is economically viable to use UTC as an energy efficiency measure in Harbin with net present value of 333$/m2 and payback time of 10.5years. With better coordination with architectural design at early stage in a project, this building-integrated solar air heating system can be both esthetically and technically viable in cold climate of China.

Energy demands and potential savings in European office buildings: Case studies based on EnergyPlus simulations

This article presents key energy use figures and explores the energy saving potentials in office buildings across Europe by simulating several currently available scenarios. The information provided in this research work is based on a review of relevant literature and the results of EnergyPlus simulations of a reference office building that can be considered as a representative office building across Europe. Three locations were selected to represent the three climate zones in which Europe was divided.Lighting has been pointed out as an area with significant improvement potentials. These improvements have been investigated by using two scenarios with different lighting control systems. In both cases and regardless of the location of the office building, the energy savings were achieved with already existing technology and will bring important reductions in the overall energy bill.Two further aspects were investigated in this work: the first one is an improvement of the insulation of the windows and the external walls (U-value) and the second one the orientation of the building.Unlikely to the lighting improvements, the location of the buildings highly influences the amount of energy required by HVAC systems. It is observed that higher insulation factors are recommended in cold and medium climate zones while they should be carefully chosen in the warmer climate zones. Office buildings constructed in warm climate zones are subjected to higher heat gains that cannot be easily released from buildings within a well-insulated envelope. Consequently, the energy demand for cooling purposes is increased, affecting the overall energy consumption and the economic performance of the building.