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Suffered from serious air pollution, Beijing, the capital of China, has implemented multiple measures to reduce the discharge of PM 2.5 (particulate matter with aerodynamic diameters of less than 2.5 μm). The average annual PM 2.5 concentration of Beijing has shown a continued decline in recent years. However, the improvement was not obvious during the heating season, which had heavier pollution than the non-heating season. Analyzing the spatial distribution of PM 2.5 concentrations during heating and non-heating seasons, as well as their spatial differences, is believed to benefit the study of spatial-temporal variation of air pollution and provide scientific reference for the control of air pollution in Beijing. In this study, land use regression (LUR) model was employed to simulate the spatial distribution of PM 2.5 concentrations in Beijing during heating and non-heating seasons in 2015. The spatial distribution of the concentration difference between heating and non-heating seasons was analyzed, and the influencing factors were also examined. The results showed that: (1) PM 2.5 concentrations during heating and non-heating seasons, as well as their differences, were clearly at a maximum in the south and east of Beijing and at a minimum in the north and west; (2) the area with the biggest concentration difference was situated in a suburban area to the south and east, as well as in outer suburbs to the southeast and northwest; and (3) wind speed, area of transport land and industrial-mining-warehouse land were the main influence factors for the PM 2.5 concentration difference in the central, eastern and southern area. Heating activity was not the only cause for the increased PM 2.5 concentration during the heating season, vehicle emission, industrial discharge and regional transport of pollutants also played varied roles in PM 2.5 pollution in different area. Image 1 • Spatial distribution differences in PM 2.5 concentrations between heating and non-heating seasons in Beijing was exhibited. • PM 2.5 concentrations differences were at a maximum in the south and east regions. • Wind, transportation and industry related to the PM 2.5 concentrations difference in the south and east regions. Wind, transportation and industry were the main influence factors for the spatial distribution of PM 2.5 concentration difference in the central, eastern and southern area. [ABSTRACT FROM AUTHOR]

In order to investigate the effects of the temporary strengthening of air quality assurance controlling measures during the Beijing 2015 IAAF World Championships and the Military Parade Assurance Period (MPAP) in China, we collected daily PM 2.5 aerosol samples at three typical sites (urban downtown, suburban and rural background area, respectively) in Beijing and investigated the variations of concentration of the water-soluble ions, elemental constituents, organic carbon (OC) and elemental carbon (EC) in PM 2.5 from Aug.15 to Sept.10, 2015. Simultaneously, 1-h high-resolution continuous monitoring results of PM 2.5 mass concentration as well as the chemical components which were measured at another online monitoring urban site were incorporated. The concentrations of PM 2.5 and other gaseous pollutants (SO 2 , NO 2 and CO) during the parade control period (Aug.20-Sept.3) exhibited a substantially decrease compared with the concentrations during both the non-control (August 15 to August 19 and September 4 to September 10) period and the same period in 2014. According to the CMC results, the major components were identified as secondary inorganic aerosol (SIA, the combination of sulfate, ammonium and nitrate), mineral dust and particular organic matter (POM), which together accounted for more than 80% of PM 2.5 in urban and suburban sites. POM is found to account for the largest proportion, and the obviously higher proportion of POM in the urban area revealed the significance contribution from vehicles. Compared with the non-control period, the mass concentrations of SIA and secondary organic carbon (SOC) decreased obviously. However, SIA and SOC are observed to play an important role in contributing to the rapid growth process of PM 2.5 under unfavorable meteorological conditions during the control period. In view of the gradual improvement of air quality in Beijing, as well as the contribution of secondary aerosol formations in total PM 2.5 , effective control of primary gaseous pollutants and volatile organic compounds (VOCs) will be very significant for further lowering the concentration of PM 2.5 in Beijing in normal time. [ABSTRACT FROM AUTHOR]

The Beijing 2008 Olympics Research and Development Project (B08RDP), initiated in 2004 under the World Meteorological Organization (WMO) World Weather Research Programme (WWRP), undertook the research and development of mesoscale ensemble prediction systems (MEPSs) and their application to weather forecast support during the Beijing Olympic Games. Six MEPSs from six countries, representing the state-of-the-art regional EPSs with near-real-time capabilities and emphasizing on the 6-36-h forecast lead times, participated in the project. The background, objectives, and implementation of B08RDP, as well as the six MEPSs, are reviewed. The accomplishments are summarized, which include 1) providing value-added service to the Olympic Games, 2) advancing MEPS-related research, 3) accelerating the transition from research to operations, and 4) training forecasters in utilizing forecast uncertainty products. The B08RDP has fulfilled its research (MEPS development) and demonstration (value-added service) purposes. The research conducted covers the areas of verification, examining the value of MEPS relative to other numerical weather prediction (NWP) systems, combining multimodel or multicenter ensembles, bias correction, ensemble perturbations [[initial condition (IC), lateral boundary condition (LBC), land surface IC, and model physics]], downscaling, forecast applications, data assimilation, and storm-scale ensemble modeling. Seven scientific issues important to MEPS have been identified. It is recognized that the daily use of forecast uncertainty information by forecasters remains a challenge. Development of forecaster-friendly products and training activities should be a long-term effort and needs to be continuously enhanced. The B08RDP dataset is also a valuable asset to the research community. The experience gained in international collaboration, organization, and implementation of a multination regional EPS for a common goal and to address common scientific issues can be shared by the ongoing projects The Observing System Research and Predictability Experiment (THORPEX) Interactive Grand Global Ensemble-Limited Area Models (TIGGE-LAM) and North American Ensemble Forecast System-Limited Area Models (NAEFS-LAM). [ABSTRACT FROM AUTHOR]

During the period around the Beijing 2008 Olympic Games, the Beijing 2008 Olympics Research and Development Project (B08RDP) was conducted as part of the World Weather Research Program short-range weather forecasting research project. Mesoscale ensemble prediction (MEP) experiments were carried out by six organizations in near-real time, in order to share their experiences in the development of MEP systems. The purpose of this study is to objectively verify these experiments and to clarify the problems associated with the current MEP systems through the same experiences. Verification was performed using the MEP outputs interpolated into a common verification domain with a horizontal resolution of 15 km. For all systems, the ensemble spreads grew as the forecast time increased, and the ensemble mean improved the forecast errors compared with individual control forecasts in the verification against the analysis fields. However, each system exhibited individual characteristics according to the MEP method. Some participants used physical perturbation methods. The significance of these methods was confirmed by the verification. However, the mean error (ME) of the ensemble forecast in some systems was worse than that of the individual control forecast. This result suggests that it is necessary to pay careful attention to physical perturbations. [ABSTRACT FROM AUTHOR]

Abstract: We report an outbreak of food poisoning that occurred in August 2008 in a group of 13 persons who ate Stewed Pork Balls in Brown Sauce in Beijing. Epidemiology investigation and case-control analysis indicated that the Stewed Pork Balls in Brown Sauce was the source of food poisoning (OR 3.34, 95% CI 1.30–8.65). With the different measurements including API 20E and PCR, Dienes typing and PFGE, Proteus mirabilis was identified as a contributor to this matter, which evaluated by analyzing the collectives, which derived from contaminated food, patients, cook handlers and waiter. So this is the first report that P. mirabilis as a culprit resulted in food poisoning in Beijing. [Copyright &y& Elsevier]

Abstract: We examined the concentrations of 11 trace metals in tissues from 10 body parts of Great Tits and Greenfinches collected at Badachu Park in the Western Mountains of Beijing, China to assess the metal accumulation level, distribution among body parts, and species and gender related variations. The highest concentrations of Hg, Ni, Zn, and Mn were found in the feather; Pb and Co in the bone; Cd, Cr, and Se in the kidney, and Cu in the liver and heart. Metal concentrations had substantial interspecific variation with Great Tits showing higher levels of Hg, Cr, Ni, and Mn than Greenfinches in tissues of most body parts. Gender related variations were body part and species specific. Meta-analyses using data from this study and other studies suggested that metal concentrations of Great Tits at our study site were relatively low and below the toxic levels. [Copyright &y& Elsevier]

The soil organic carbon isotope indicator (δ13C org) is widely used in paleoecology and paleoclimate reconstruction due to its ability to record the history of paleovegetation change. Although it has been used as a proxy for precipitation reconstruction, increasing evidence suggests that temperature has played a crucial role in influencing the relative abundance of C 3 /C 4 plants in the mid-latitudes during the interglacial period. This opens up the possibility of reconstructing Holocene temperature using δ13C org. In this study, the variation of δ13C org values in a Holocene loess profile (GLH profile), located in the eastern Hunshandake Sandy Land, China, was investigated. And we analyzed the correlation between δ13C org values and modern temperatures for a total of 792 surface soil samples from mid-latitudes of the Northern Hemisphere, which had thermal conditions comparable to the GLH profile. Strong positive correlations were found between δ13C org values of surface soil samples and both summer temperatures (r = 0.672, p < 0.001) and growing season temperatures (r = 0.669, p < 0.001). Additionally, δ13C org values showed significant positive correlations with accumulated temperatures above 10 °C (r = 0.641, p < 0.001) and above 0 °C (r = 0.527, p < 0.001). However, the correlation with mean annual temperature was weak (r = 0.280, p < 0.001). The δ13C org variation in the GLH profile recorded a mixed C 3 /C 4 vegetation composition, with C 4 plants comprising between 23.40% and 1.70% of the total abundance during the Holocene. The combined evidence from modern processes and profile variations confirms that warm-season temperature was the main factor driving variations in the δ13C org values in the GLH profile. Therefore, we used δ13C org –temperature conversion equations to quantify Holocene seasonal and accumulated temperatures based on the GLH profile. The reconstructed summer temperatures peaked at 9.3 ka, followed by a fluctuating downward trend during the mid- and late-Holocene, which is consistent with variations in summer solar insolation. Mean summer temperatures were relatively high at 23.3 °C and 22.5 °C in the early and mid-Holocene, respectively, while the lowest mean summer temperature of 20.5 °C occurred in the late Holocene. Accumulated temperatures above 10 °C and above 0 °C in the early Holocene were 3722 °C·d and 4641 °C·d, respectively, similar to modern observations in the Beijing area, indicating a southward shift of the temperature zone by nearly three degrees of latitude since the early Holocene. These reconstruction results are supported by modern observations, TraCE21 simulations, and other studies. This study is significant for extending the application of the δ13C org indicator for quantitative paleoclimate reconstructions. It verifies its effectiveness in quantifying Holocene temperatures in the marginal zone of the East Asian summer monsoon. • Attempt to reconstruct paleotemperatures quantitatively using the δ13C org indicator. • Conversion equations established between δ13C org - temperature in mid-latitude regions. • Holocene summer temperature and accumulated temperature (T ≥ 0 °C, T ≥ 10 °C) obtained. • Holocene summer temperature peaked at 9.3 ka and was controlled by solar insolation forcing. • Temperature zone shifted nearly three latitudes southward since early Holocene. [ABSTRACT FROM AUTHOR]