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The climate of Yangtze River Basin in China is cold and humid in winter. Conventional air-conditioning systems may cause high energy consumption and uncomfortable microclimatic conditions especially for lower body of indoor occupants. This study investigated four personalized seat heating systems, in a typical office room in Shanghai during winter, based on heated floor panels including heated floor panels + ordinary chair (HF-OC), heated floor panels + insulated chair (HF-IC), heated floor panels +insulated chair and leg box (HF-IC-LB) and overall personalized heating (OPH). The surface temperature of walls and heated floor panels, and the indoor air temperature at different positions were recorded with thermocouples. The hourly energy consumptions of the proposed personalized seat heating systems were measured and compared with a conventional split type air conditioner. Questionnaires of thermal sensation and comfort were carried out among 10 university students. Compared with HF-OC, HF-IC could improve the thermal comfort to a certain extent, while HF-IC-LB provided the optimal thermal micro-environment for the lower body other than other body parts. The OPH systems were proven effective to provide satisfactory thermal environment for all body parts at lower indoor temperature (12–16°C) with much less energy consumption than room air conditioners. [ABSTRACT FROM AUTHOR]

Abstract: Hotel buildings consume a significant amount of energy, especially their chiller systems. This study aims to create a model of the power consumption of the hotel chillers, and to identify the practical means to reduce the power usage of chillers. The examined parameters include air-conditioned floor area, guest floor area, gross floor area, number of employees, room occupancy, food cover, outdoor air temperature, window velocity, service type and relative humidity. It is anticipated that the developed modeling equation may provide a reference for hotel engineers to forecast any diagnostic problems and form a benchmarking indicator for comparing chillers’ energy efficiency. A survey of hotels in Shanghai was carried out to collect energy consumption data of chillers during air-conditioned cooling months. Regression analysis indicates that number of staff was a major and statistically accepted factor in explaining the electricity consumption of chiller in hotels. In addition, the paper discusses some means and suggestions in reducing chillers’ power consumption. [Copyright &y& Elsevier]

A rainfall that occurred during 0200-1400 Beijing Standard Time (BST) 25 August 2008 shows the rapid development of a convective system, a short life span, and a record rate of 117.5 mm h-1 for Xujiahui station since 1872. To study this torrential rainfall process, the partitioning method of Q vector is developed, in which a moist Q vector is first separated into a dry ageostrophic Q vector (QD ) and a diabatic-heating component. The dry ageostrophic Q vector is further partitioned along isothermal lines in the natural coordinate to identify different scale forcing in adiabatic atmosphere, and the large-scale and convective condensational heating in non-uniform saturated atmosphere, convective condensational heating, and Laplace of diabatic heating that includes radiative heating and other heating and cooling processes, are calculated to study the forcing from diabatic heating. The effects of the environmental conditions on the development of the rainfall processes are diagnosed by performing the partitioning of Q vector based on 6-hourly NCEP/NCAR Final Analysis (FNL) data with the horizontal resolution of 1° × 1° . The results include the following: (1) a low-pressure inverted trough associated with the landfall of Typhoon Nuri (2008), a strong southwesterly jet along the western side of the subtropical high, and an eastward-propagating westerly low-pressure trough provide favorable synoptic conditions for the development of torrential rainfall; (2) the analysis of QD vector showed that the upward motions forced by the convergence of QD vector in the lower troposphere (1000-600 hPa) favor the development of torrential rainfall. When QD vector converges in the upper troposphere (500-100 hPa), upward motions in the whole air column intensify significantly to accelerate the development of torrential rainfall; (3) the partitioning analysis of QD vector reveals that large-scale forcing persistently favors the development of torrential rainfall whereas the mesoscale forcing speeds up the torrential rainfall; (4) the calculations of large-scale condensational heating in non-uniform saturated atmosphere, convective condensational heating, and Laplace of diabatic heating showed that the forcing related to diabatic heating has the positive feedback on the convective development, and such positive feedback decays and dissipates when the convective system propagates eastward and weakens. [ABSTRACT FROM AUTHOR]

Based on meteorological data from 1978 to 2007, we investigated the annual, seasonal, and fixed hourly variations of Shanghai urban heat island (UHI) in urban and suburban areas and spatial distribution of UHI. The results demonstrated a remarkable interannual increase of UHI intensity in Shanghai. The UHI was the strongest in autumn and the weakest in summer, as a consequence of the prevailing weather conditions. Similar to previous studies of other cities, the UHI in Shanghai was stronger in the nighttime than in the daytime. The SW–NE cross section followed the general cross section of the typical UHI described by Oke () who defines its characteristic parts as “cliff”, “plateau”, and “peak”. Analysis of the association of UHI and urbanization indicated that the UHI increased with the expansion of population and rapid increase of gross domestic product. The continuous increase of power consumption and area of paved road and decrease of area of cropland caused the growth of UHI intensity. Green land had a positive effect on mitigation of heat island based on an inversed U-shaped curve with UHI intensity. [ABSTRACT FROM AUTHOR]

Although the environment can greatly influence an individual's sleep quality, China is yet to conduct comprehensive research on the topic. This study investigated the bedroom environment and sleep quality of 41 households during summer in Shanghai. Bedroom environments were comprehensively evaluated through environmental perception questionnaires filled by participants after waking up every morning. Parameters, such as air temperature, relative humidity, CO 2 concentration, and noise level were continuously monitored. Furthermore, participants' sleep quality was observed using both subjective questionnaires and physiological measures. Environmental measurements showed that the most comfortable air temperature and relative humidity was 24.8 °C and 64%, respectively. Physiological measurements showed that the average duration of slow wave sleep (SWS) and sleep efficiency (SE) was 73.8 min and 86.7%, respectively. Additionally, SWS was negatively correlated with air temperature (r = −0.377, p = 0.015) and CO 2 concentration (r = −0.362, p = 0.02), and SE was negatively correlated with noise level (r = −0.32, p = 0.042). The subjective and objective results consistently indicated that higher air temperature, CO 2 concentration, and noise level leads to poor sleep quality in summer. In addition, air temperature and CO 2 concentration had a greater impact on the sleep quality of males, while noise level had a greater impact on the sleep quality of females. • Questionnaires and measurements were combined to figure out the relationship between environment and sleep quality. • Environmental factors and environmental perception votes showed a good linear relationship. • During sleep period, the most comfortable air temperature and relative humidity were 24.8 °C and 64%, respectively. • Air temperature and CO 2 level had a greater impact on males' sleep, while noise level had a greater impact on females'. [ABSTRACT FROM AUTHOR]

The threshold effect in the relationship between impervious surfaces and water quality has been a focus in past decades, but little attention has been paid to how the threshold effect changes during a rapid urbanization period. This study reveals the temporal variation of threshold effect in the relationship between the percentage of total impervious area (PTIA) and water quality indicators in a reticular river network area in Shanghai, China. The PTIA was surveyed and defined using the ISC method (impervious surface coefficients). A segmented regression model was used to disclose the non-linear relationship between PTIA and water quality. It is confirmed that the threshold effect was different in terms of water quality indicators, but the effect size became smaller as the threshold increased with urbanization level during the period of 1989–2010. Meteorological conditions make influence on the threshold effect, it can be found that the effect is more significant under higher air temperature conditions, while in the lower temperature situation, there is no significant threshold effect. Image 1 • Non-linear relationship is disclosed between PTIA and water quality. • Threshold effect is different in terms of water quality indicators. • The threshold increases with urbanization level. • Threshold effect becomes less apparent and may disappear in the near future. There is an obvious threshold effect between impervious surfaces and water quality, but the threshold effect decreases over time. [ABSTRACT FROM AUTHOR]