Different Climate Zones In China Research Articles

A ventilator that responds to outdoor conditions for ventilation and air filtration

Because of haze and fog in some countries, the outdoor air is polluted and cannot be directly drawn into rooms for ventilation. A ventilator with air filtration may be required. However, as outdoor particulate concentrations vary greatly with time, it is not ideal to operate high-efficiency particulate air (HEPA) filtration continually. This investigation proposed a ventilator with multiple modes of ventilation and air filtration. The ventilator could be switched between modes according to the outdoor and indoor air conditions. The ventilation rate and indoor particle concentrations in a test room equipped with the proposed ventilator were modelled by the EnergyPlus software program and validated with experimental data. The validated model was then used to evaluate indoor air quality and energy consumption in a hypothetical apartment located in each of five different climatic zones in China. The performance of the proposed ventilator was compared to that of a market-available outdoor air blower. It was found that to obtain the same acceptable indoor air quality, the necessary operating time for the proposed ventilator in the HEPA filtration mode was approximately 70% shorter than for the outdoor air blower, and the ventilator required approximately 30% less operating energy. In some southern cities in China, mechanically driven medium-efficiency filtration was sufficient to reduce the PM2.5 concentration to the acceptable level.

Daylight performance assessment of atrium skylight with integrated semi-transparent photovoltaic for different climate zones in China

The utilization of atriums in large space public buildings has significantly improved the internal lighting performance, but due to the harsh external environment, the application of large-scale skylights also brings higher heating or cooling energy consumption. Skylight Integrated Photovoltaic (SIPV) technology can not only use solar energy efficiently, but also has a significant shading effect, avoiding direct impact on the indoor light and thermal environment. At present, quite limited researches have studied the uncomfortable light environment of atrium caused by the application of semi-transparent photovoltaics in skylights. Therefore, it is very important to propose effective solutions to improve the daylight performance of these spaces or those with similar daylight climates.In this work, the indoor light environment has been systematically investigated through simulation employing DAYSIM tool. Both static and dynamic simulation analysis were carried out over the selected skylight glass to determine its appropriate area ratio of photovoltaic materials for representative Chinese cities. The optimal area ratio parameter range of thin film (TF) and crystalline silicon (C-Si) photovoltaic materials resulted in range of: 50–60% for both TF and C-Si in Xi'an represented area; 60–70% for TF, and 50–70% for C-Si in Beijing represented area; 50–60% for TF, and 60-70% for C-Si in Shanghai represented area; 50–60% for TF, and 50-70% for C-Si in Guangzhou represented area; 40–60% for TF, and 40-60% for C-Si in Harbin represented area; 30–50% for both TF and C-Si in Chongqing represented area. The optimal area ratio based design strategies of SIPV under various climatic conditions were then summarized.

Calculation of evapotranspiration in different climatic zones combining the long-term monitoring data with bootstrap method

Evapotranspiration (ET) is a central process in the climate system that plays a crucial role in the regional water cycle and climate regulation. However, estimating the effects of regional ET on the regional water cycle and climate regulation remains challenging due to the lack of quantitative methods and large-scale direct observational data. This study develops a new method to estimate evapotranspiration at regional scales using long-term monitoring data and the bootstrap resampling approach to calculate the ET unit area per year for China. This study applies the deviance information criterion as a goodness-of-fit index to select the most optimal formula for estimating regional ET for different climatic zones in China. The bootstrap resampling method was used to estimate parameter distribution in different climatic zones based on the outcome of 2000 trials. The results show that the predicted ET of adjacent climates overlaps with each other. The subtropical monsoonal climatic zone had the widest range of predicted ET (0–8000 mm/year), followed by the temperate and monsoonal climatic zones (0–1500 mm/year), mountain plateau climatic zone (0–1000 mm/year), and temperate continental climatic zone (0–500 mm/year). The probability distributions and isopleths of regionally predicted ET were also determined for China. The methods used in this study provide a promising tool to assess the effects of introducing large-scale forestation or restoration of trees on local water resources management.

Effects of watershed char and climate variables on annual runoff in different climatic zones in China

The complex interactions between climate and watershed characteristics lead to diverse annual runoff responses. Understanding the mechanism by which different climatic and watershed factors affect annual runoff is helpful in understanding the resulting changes in the hydrological process. In this study, the characteristics of 73 watersheds were analyzed. The basins were divided into three categories according to their climatic regions: temperate continental climate (n = 7); temperate monsoon climate(n = 36); and subtropical monsoon climate(n = 30). Correlation analysis, linear regression, and path analysis were used to quantify the effects of selected watershed characteristics and meteorological conditions on long-term runoff. Results showed that the average annual runoff coefficient was strongly correlated with basin area, showing a scale effect. The average annual runoff depth was strongly positively correlated with precipitation for the all watersheds. As the drought index (DI, the ratio of annual evaporation capacity to annual precipitation) increased, the annual runoff depth decreased logarithmically. The average annual rainfall and runoff depth of watersheds in the subtropical monsoon climate zone were significantly higher than those in other climatic zones, and there was no significant difference in potential evaporation between the temperate monsoon climate and subtropical monsoon climate zones. With increases in both the drought index (Ep/P) and moisture index (E/P), the vegetation distribution in the basin showed an increasing trend in farmland area and decreasing trend in forest area. Path analysis showed that rainfall had a positive effect on annual average runoff depth (ranging from 31 to 62%) while actual evapotranspiration had a negative impact (ranging from 17 to 47%). For all basins, a negative effect (13–25%) of basin area on runoff depth was observed, while forestland area had a positive effect (7–39%) on runoff depth. This study further quantified the effects of climatic and geographical factors on the long-term water balance in different climatic regions.

Retrofitting High-Rise Residential Building in Cold and Severe Cold Zones of China—A Deterministic Decision-Making Mechanism

This study aimed to develop a deterministic decision-making mechanism for finding the optimum set of retrofit solutions of existing high-rise residential buildings in two different climatic zones of China. The retrofit solutions were critically examined with different energy saving targets based on the local climatic conditions, building features, and retrofit costs in cold and severe cold zones comparatively. By making the extensive review and analyzing considerable statistics data and cost information, net present value (NPV) method was employed in the prototype building apartments to develop this deterministic model. The results demonstrated that the heating system is the most important factor in saving energy and obtaining the optimum revenue in these two regions. The highest optimal NPV can be obtained by achieving 60% energy saving in the cold zone, as energy saving is around 319 kWh/m2/year with the total retrofit costs of USD $3560, while it is 281 kWh/m2/year with the total retrofit costs of USD $3480 to achieve the 50% energy-saving target in the severe cold zone. Based on the analysis of energy savings and retrofit costs, the results can be effectively implemented for the purpose of creating sustainable retrofits in existing buildings, and the model can be adapted for selecting appropriate retrofit choices in other climatic zones.

Effect of Building Form on Energy Consumption of Academic Library Buildings in Different Climate Zones in China

This research focuses on the energy efficiency of academic library buildings with their shape in four major climate zones in China. According to their varieties in shapes and their representativeness in current constructions, eight hypothetical models of four types (point, slab, block, comb) are built based on the form of actual academic library buildings in recent years. The relationship between the building forms and building energy consumption is simulated and analysed with the software Design Builder. Results show that with the same construction area, different building forms can lead to variations in energy consumption in different climate zones. The slab-type is relatively energy-saving in most climate zones, while the block-type and E-shaped comb-type are more suitable for hot summer and warm winter zone. The building shape coefficient is an important parameter for reducing energy consumption in severe cold and cold zone, but the role of building depth is also sensitive. This information is dedicated to the architects at the early design stage of a project from the perspective of energy consumption.

A Data-driven Approach for Sustainable Building Retrofit—A Case Study of Different Climate Zones in China

This study presents a data-driven retrofitting approach by systematically analyzing the energy performance of existing high-rise residential buildings using a normative calculation logic-based simulation method. To demonstrate the practicality of the approach, typical existing buildings in five climate zones of China are analyzed based on the local building characteristics and climatic conditions. The results show that the total energy consumption is 544 kWh/m2/year in the severe cold zone, which is slightly higher than that in the cold zone (519 kWh/m2/year), but double that in the hot summer and cold winter zone, three times higher than that in the warm zone, and five times above that in the temperate zone. The dominant energy needs in different climatic zones are distinctive. The identified potentially suitable retrofitting measures are important in reducing large-scale energy consumption and can be used in supporting sustainable retrofit decisions for existing high-rise residential buildings in different climatic zones.

A method for evaluating both shading and power generation effects of rooftop solar PV panels for different climate zones of China

The photovoltaic (PV) roofs have two main energy-saving effects, which are shading and power supply. Considering the shading and power generation gain jointly, a roof is changed from the building energy end to the building energy supply end, thus changing its energy use system greatly. Therefore, this paper carries out research on the comprehensive energy-saving effect integrating the shading and the power supply gain. Three types of PV rooftops, namely, horizontally-mounted overhead PV rooftop, tilted overhead PV rooftop, and attached PV rooftop are studied to explore their impacts on the heat gain and heat loss of the roof and building’s heating and cooling load. In order to estimate the overall energy-saving in different climatic regions in China, an overall energy-saving evaluation method that considers the power generation and shading benefit effects of the PV rooftop is proposed. Based on the climate and solar radiation zones in China, 13 respective cities are selected to be included in the research. The results show that, by considering only the shading effect of PV panels, the tilted PV is more suitable in summer, reducing the heat input, whereas the horizontally-mounted PV is more effective in winter to prevent more heat loss. Regarding the overall energy-saving that considers both the shading and power generation effects of PV panels, building with horizontally-mounted PV rooftop has the highest efficiency in the summer season, while the building with tilted PV rooftop has the highest efficiency in the winter season. The model and analysis of the overall energy-saving presented in this work can provide a guide for the application of rooftop solar PV panels in different climate zones in China.

Concentration characteristics of gaseous carbonyl compounds in urban houses in two different climatic zones of China and health risk assessment for schoolchildren

This paper reported concentration characteristics of thirteen kinds of gaseous carbonyl compounds (CCs) in urban houses with schoolchildren in two different climatic zones of China, estimated schoolchildren’s daily inhalation dose of formaldehyde and acetaldehyde, and then evaluated potential health risks for schoolchildren. Formaldehyde was the most abundant CCs in the houses, following by acetone and acetaldehyde. Mean concentrations of indoor formaldehyde, acetaldehyde and acetone in summer were 39.4 μg/m3, 16.1 μg/m3 and 26.7 μg/m3, which were higher than the concentrations of 21.4 μg/m3, 9.9 μg/m3 and 16.5 μg/m3 in winter. Compared to winter, more kinds of CCs were detected in summer. The significant positive correlations between different CCs indicated CCs were coexisting in indoor environments and released from the same sources. Due to a longer time spent in child’s bedrooms, children’s inhalation doses of formaldehyde and acetaldehyde in child’s bedrooms were much higher than those in living rooms. The impact of formaldehyde exposure in the houses on children’s health was greater than acetaldehyde exposure. The average risk quotients for formaldehyde exposure in winter and summer were 20.74 and 39.34, while 4.65 and 6.97 for formaldehyde exposure. These results supplemented the limited data concerning children’s exposure to CCs and associated health risk in the houses of China.

Screening High CO2-Tolerant Oleaginous Microalgae from Genera Desmodesmus and Scenedesmus.

Microalgae from genus Scenedesmus sensu lato (including Desmodesmus and Scenedesmus) were reported to be particularly suitable candidates for CO2 biomitigation. In this study, 16 strains from Scenedesmus sensu lato were obtained from different climate zones of China and their phylogenetic positions were determined. Seven strains out of the 16 showed high CO2 tolerance and grew much faster under 20% CO2 than air condition. Two representatives from genera Desmodesmus (NMD46) and Scenedesmus (HBX310) respectively were selected due to their higher lipid productivity, and the maximum value of 146mgL-1day-1 was achieved in NMD46. Triacylglycerols increased with the rising of CO2 levels from 0.04 to 15% in NMD46, while they changed little in HBX310. High CO2 level decreased the polyunsaturated fatty acid content in NMD46 but increased it in HBX310. NMD46 is more suitable for standardized biodiesel production in view of its lipid and fatty acid composition responses to high CO2.

Study on the impact of window shades’ physical characteristics and opening modes on air conditioning energy consumption in China

• A shading schedule of residential buildings is obtained through 949 questionnaires. • Two opening modes of window shades were considered. • Analyzed the six physical characteristics of window shades on energy consumption. • The results could allow design guidelines for developing the performance of window shades. This paper focused on the impact of window shades’ physical characteristics and opening modes on annual air conditioning energy consumption of residential buildings in China. Three building models with different window layouts were proposed initially, and then validated by the dimensionless indicator annual energy performance (AEP) to determine the final building model adopted in this study. Harbin, Beijing, Guangzhou, Changsha and Kunming were selected to represent five different climate zones in China. The shading model has taken six physical characteristics of window shades, viz. outer emissivity, inner emissivity, solar transmittance, solar reflectance, thermal infrared transmittance, conductivity and two opening modes, viz. up & down mode as well as left & right mode, into consideration. Besides, the window shades operation schedule was summarized through 949 valid questionnaires. The annual air conditioning energy consumption was calculated via EnergyPlus software, and then the impact of the above different opening modes and parameters on energy use were investigated. The analysis results indicated that the top & bottom opening mode is better than the left & right mode when used in Harbin, and the effect of two different modes in air conditioning energy consumption in Kunming is similar. But in the other three cities, the left and right mode is preferred. Besides, the analysis results of the impact of different physical characteristics on air conditioning energy use in different climate zones could help improve the energy performance of window shades.

Combined unsteady denudation and climatic gradient factors constrain carbonate landscape evolution: New insights from in situ cosmogenic 36Cl

Abstract In situ cosmogenic nuclides are widely employed to quantify topographic and geomorphic landscape evolution. However, few studies are devoted to investigating possibly unsteady denudation. In this work the denudation rates of five surface bedrock and one depth profile are measured using in situ cosmogenic 36Cl in different climate zones in China; cosmogenic 36Cl is a powerful proxy for the surface denudation processes of carbonate landscapes in different climatic gradients since carbonates are more sensitive to climate change than silicates. Compiling previous worldwide surface denudation studies in different gradients, we find that: (I) denudation rate increases systematically with mean annual precipitation (MAP) in arid climatic zones (MAP lower than ~700 mm yr−1) and is dominated by long-term climatic gradients; (II) humid climatic zone (MAP greater than ~700 mm yr−1) denudation rates are about constrained to 34.1 ± 11.7 mm kyr−1 by carbonate dissolution kinetics; and (III) denudation rate is also influenced by short-term physical erosion or abrupt erosive events. Accordingly, the reconstructed evolutionary history of the Guizhou depth profile results from either a relatively high denudation rate (55.5–4.4 +5.6 mm kyr−1) and long duration exposure (274–147 +120 ka), or an alternative a low denudation rate (0.8–0.8 +13.3 mm kyr−1) and a recent abrupt erosive event (13.0–1.6 +1.9 ka). These two possible solutions suggest that assumed long-term averaged denudation rate can conceal episodic erosion events. Given tectonic quiescence we propose that climate change might mainly control an erosive event during the last glacial termination (~14 ka), which also implies that caution should be taken when determining the denudation rate of a landscape where climate change and/or tectonic activity plays an important role.

An Introduction to Neighborhood Sustainability Assessment Tool (NSAT) Study for China from Comprehensive Analysis of Eight Asian Tools

In comparison to city-level and building-level sustainability research, neighborhood-level sustainable urban development is less studied. One of the ways of achieving sustainability at this level is the use of the Neighborhood Sustainability Assessment Tool (NSAT), which focuses on the sustainable urban development of districts, communities, and neighborhoods. NSAT is comprised of urban sustainable indicators and associated points ascribed towards achieving specific urban agendas, called headline sustainability indicators (HSIs) and themes. In China, neighborhood-level sustainability agenda has just been recently established in 2017. Hence, there is an immediate need for NSAT development of multiple cities responding to specific regions of different climate zones in China. As an example, this study utilizes the case of Ningbo City, located in east China, for such NSAT development. This paper provides a comprehensive analytical and comparison study of eight Asian NSATs to highlight compatibilities and extract specific indicators for a new NSAT development for China. The results from this comparative and analytical study, developed through a multidimensional approach of sustainable pathway model (SPM) inform a new NSAT development in a new context. This novel contribution is significant in a context where neighborhood sustainability measures are recently developed. This study serves as the starting point for future research of NSATs in China and other countries.

Climate change impacts on extreme energy consumption of office buildings in different climate zones of China

In this paper, 16 cities representing four major architectural climate zones of China were selected, and the heating and cooling loads of office building during the period of 1961–2017 were simulated by using TRNSYS software. Daily extreme heating and cooling loads were determined by percentile methods, and the climate change impact on extreme loads was analyzed. The results showed that the days of extreme heating load of office building significantly decreased in almost all the selected cities, whereas there were no significant changes in the days of extreme cooling load. The daily extreme heating load was dominantly affected by the temperature (R2 = 0.43–0.79), but the daily extreme cooling load was related to multiple climate factors, including temperature, relative humidity, and solar radiation. Single temperature can only explain 3–37% of the changes of daily extreme cooling load, and the combination of multiple climate factors can explain 58–85%. Importantly, the effect of temperature on extreme cooling load showed decrease from the cold to hot climate zones, but the impacts of relative humidity and solar radiation gradually increased. These results suggest that the maximum design capacity of heating systems can properly decrease, and the design capacity of cooling systems may not largely increase with the climate warming. In addition, the combined effect of multiple climate factors rather than the single temperature, as well as the different responses of extreme cooling energy consumption to climate change in different climate zones, should be considered when making measures for improving operating efficiency of air-conditioning system.

Climate-zone-dependent effect mechanism of humic acid and fulvic acid extracted from river sediments on aggregation behavior of graphene oxide

Climate factors could affect the physicochemical properties of dissolved organic matter (DOM) in river sediments, which potentially influence the stability of nanoparticles in natural waters. In this study, we extracted humic acid (HA) and fulvic acid (FA) from river sediments in different climate zones of China. Their effect with different concentrations (0.2 and 1 mg·C·L−1) on the aggregation kinetics of large (589 nm) and small graphene oxide (GO, 200 nm) in NaCl solutions was investigated. Both concentrations of HA/FA significantly inhibited the aggregation of small GO because of the steric forces rendered by DOM. For large GO, the inhibition effect of HA on aggregation was higher than FA because of the higher molecular weight, longer carbon chain length, and more structure complexity of HA. Interestingly, with 0.2 mg·C·L−1 HA and large GO, Makou in Subtropical monsoon climate zone decreased the aggregation rate more significantly due to its larger molecular weight, while, Maqin in the Plateau and mountain (PM) climate zone with smaller molecular weight and greater hydrophobicity showed lower inhibition effect on the aggregation. One mg·C·L−1 FA with high polarity from Tangke in PM climate zone and Panjin from Temperate monsoon climate zone showed more stability ability towards large GO. Derjaguin-landau-verwey-overbeek (DLVO) theory indicated that the interaction energy barrier between GO particles dependent on physicochemical characteristics of DOM and GO size. Understanding the climate-zone-dependent effect of sediment DOM on stability of GO is essential for anticipating its fate in natural systems.

Energy saving performance of thermochromic coatings with different colors for buildings

Thermochromic coatings are promising in lowering air conditioning energy consumption of buildings. In this paper, thermochromic coatings with five different colors are prepared and their optical properties are measured. A two-story office building model is established and simulation is conducted to evaluate the energy performance of thermochromic coatings by using a three-step control method based on their dynamic color-changing properties. A comparative analysis is carried out for thermochromic coatings, cool coating and common coating. It is observed that when the building is located in Shanghai, average daily surface temperature of thermochromic coatings is lower than the common coating during cooling period and higher than the cool coating during heating period. Annual energy consumption results indicate that thermochromic coatings can avoid the penalty of increasing heating load for cool coatings. In particular, the annual energy consumption of the office building using thermochromic coatings can be reduced by 4.28–5.02 kWh/m2 compared to the common coating, and 0.73–1.47 kWh/ m2 compared to the cool coating. Simulation of other cities in different climate zones in China reveals that thermochromic coatings have better energy saving effects especially for the areas with hot summers and cold winters, and relatively uniform distribution of cooling and heating demands.

Interactions and marginal effects of meteorological factors on haemorrhagic fever with renal syndrome in different climate zones: Evidence from 254 cities of China

BackgroundHaemorrhagic fever with renal syndrome (HFRS) is climate sensitive. HFRS-weather associations have been investigated by previous studies, but few of them looked into the interaction of meteorological factors on HFRS in different climate zones. ObjectiveWe aim to explore the interactions and marginal effects of meteorological factors on HFRS in China. MethodsHFRS surveillance data and meteorological data were collected from 254 cities during 2006–2016. A monthly time-series study design and generalized estimating equation models were adopted to estimate the interactions and marginal effects of meteorological factors on HFRS in different climate zones of China. ResultsMonthly meteorological variables and the number of HFRS cases showed seasonal fluctuations and the patterns varied by climate zone. We found that maximum lagged effects of temperature on HFRS were 1-month in temperate zone, 2-month in warm temperate zone, 3-month in subtropical zone, respectively. There is an interaction effect between mean temperature and precipitation in temperate zone, while in warm temperate zone the interaction effect was found between mean temperature and relative humidity. ConclusionThe interaction effects and marginal effects of meteorological factors on HFRS varied from region to region in China. Findings of this study may be helpful for better understanding the roles of meteorological variables in the transmission of HFRS in different climate zones, and provide implications for the development of weather-based HFRS early warning systems.

Performance assessment of CO2 supermarket refrigeration system in different climate zones of China

In this paper, a R744 Partial Cascaded Two-stage Compression Refrigeration System (R744-PC-TCS) was proposed and evaluated in terms of coefficient of performance (COP) and seasonal energy efficiency ratio (SEER) when it operated in five typical climate representative cities in China. R134a and CO2 are used as refrigerants in this study. The results show that the SEER of the supermarket refrigeration system in the severe cold zone and the mild zone is higher than that of the other climate zones. The performance of the R134a Two-stage Compression Refrigeration System (R134a-TCS) performs better than the R744 Two-stage Compression Refrigeration System (R744-TCS). However, both COP and SEER of the CO2 system can be improved significantly by adding a parallel compressor, as well as using the single-stage vapor compression partial cascade cycle for subcooling under the practical working conditions (such as R744-PC-TCS). The greatest improvement of R744-PC-TCS can be achieved in the areas with poor climatic conditions, in which COP increases by 48.9% at an ambient temperature of 39 °C, and SEER increases by the maximum of 21.5% in hot summer and warm winter zones, compared with that of R744-TCS. Compared with R134a system, the R744-PC-TCS basically achieves the comparable or even higher energy efficiency. It can be concluded that the proposed R744-PC-TCS has a great potential to replace the existing R134a refrigeration system for the supermarket refrigeration application.

The Applicability of LSTM-KNN Model for Real-Time Flood Forecasting in Different Climate Zones in China

Flow forecasting is an essential topic for flood prevention and mitigation. This study utilizes a data-driven approach, the Long Short-Term Memory neural network (LSTM), to simulate rainfall–runoff relationships for catchments with different climate conditions. The LSTM method presented was tested in three catchments with distinct climate zones in China. The recurrent neural network (RNN) was adopted for comparison to verify the superiority of the LSTM model in terms of time series prediction problems. The results of LSTM were also compared with a widely used process-based model, the Xinanjiang model (XAJ), as a benchmark to test the applicability of this novel method. The results suggest that LSTM could provide comparable quality predictions as the XAJ model and can be considered an efficient hydrology modeling approach. A real-time forecasting approach coupled with the k-nearest neighbor (KNN) algorithm as an updating method was proposed in this study to generalize the plausibility of the LSTM method for flood forecasting in a decision support system. We compared the simulation results of the LSTM and the LSTM-KNN model, which demonstrated the effectiveness of the LSTM-KNN model in the study areas and underscored the potential of the proposed model for real-time flood forecasting.

Development of the Predicted Thermal Sensation (PTS) model using the ASHRAE Global Thermal Comfort Database

In this study, existing thermal comfort models were reconsidered and analysed. A new predicted thermal sensation (PTS) model was developed, in which Gagge's two-node model was used for the calculation of thermal regulation. This model was established using data from the ASHRAE Global Thermal Comfort Database and the index of standard effective temperature (SET). This model could not only predict human thermal sensations in various environmental conditions, but also reflect the discrepancies in thermal adaptation in different taxonomies. PTS models were developed for the classification of different climatic zones in China. In addition, worldwide PTS models were proposed for the typical climate types. Some of the data from field studies were introduced to validate these models. The rationality and accuracy were demonstrated, indicating that the PTS model was a practical, flexible, and effective choice for guiding building construction, as well as for evaluating an actual thermal environment. Moreover, further directions for the model's future development were indicated.