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Qian J.,Shanxi Climate Center | Zhang X.,China Institute of Technology | Zhang J.,Shanxi Climate Center | Fan L.,Hangzhou Meteorological Bureau | Wu J.,Shanxi Province Meteorological Information Center
Acta Geographica Sinica | Year: 2010

Based on the frost date data of 52 meteorological stations over Shanxi Province from 1970 to 2009, the basic characteristics of the first and last frost dates and their changing trends were analyzed in this paper using linear trend estimation method, cumulative filter method and non-parametric statistical test method respectively, and the abrupt changing feature of the frost dates was also analyzed with Mann-Kendall method. The results show that the frost dates and frost-free period have obvious spatial and temporal changing features. Along with the latitude moving northward and the altitude rising high, the first frost appears earlier, the last frost occurs later, and the frost-free period becomes shorter. With the time changing over the past 40 years, the first frost event occurs later and the frost-free period becomes longer, while the last frost date fluctuates from year to year. For the abrupt changing feature, they all have one obvious abrupt change over the past 40 years. The abrupt change of the first frost date appears in 2000, while the abrupt changes of the last frost date and the frost-free period are detected in 1997. For the spatial distribution of their changing trend, the area in which the first frost date is postponed significantly includes the east of Jinzhong city, the north of Lüliang city, the west of Xinzhou city, the south of Yuncheng city, the northwest of Linfen city and the southern part of Datong city; the area in which the last frost date appears obviously earlier includes the east mountainous region of Jinzhong city, the eastern part of Lüliang Mountains and the western part of Xinzhou city; the area in which the frost-free period extends obviously includes the region near the Yellow River, the central-eastern part of the province and the south of Yuncheng city.


Ma Y.,Qingdao Meteorological Bureau | Gao R.,Qingdao Meteorological Bureau | Xue Y.,Qingdao Meteorological Bureau | Yang Y.,Hangzhou Meteorological Bureau | And 6 more authors.
Advances in Meteorology | Year: 2013

The Beijing 2008 Olympic and Paralympic Sailing Competitions (referred to as OPSC hereafter) were held at Qingdao during August 9-23 and September 7-13 2008, respectively. The Qingdao Meteorological Bureau was the official provider of weather support for the OPSC. Three-dimensional real-time information with high spatial-temporal resolution was obtained by the comprehensive observation system during the OPSC, which included weather radars, wind profile radars, buoys, automated weather stations, and other conventional observations. The refined forecasting system based on MM5, WRF, and statistical modules provided point-specific hourly wind forecasts for the five venues, and the severe weather monitoring and forecasting system was used in short-term forecasts and nowcasts for rainstorms, gales, and hailstones. Moreover, latest forecasting products, warnings, and weather information were communicated conveniently and timely through a synthetic, speedy, and digitalized network system to different customers. Daily weather information briefings, notice boards, websites, and community short messages were the main approaches for regatta organizers, athletes, and coaches to receive weather service products at 8:00 PM of each day and whenever new updates were available. During the period of OPSC, almost one hundred people were involved in the weather service with innovative service concept, and the weather support was found to be successful and helpful to the OPSC. © 2013 Yan Ma et al.


Zhu F.-X.,Zhejiang Academy of Agricultural Sciences | Yao Y.-L.,Zhejiang Academy of Agricultural Sciences | Wang S.-J.,Work Safety Production Science Research Institute of Zhejiang Province | Du R.-G.,Hangzhou Meteorological Bureau | And 6 more authors.
Waste Management | Year: 2015

In traditional composting, large amounts of bulking agents must be added to reduce the moisture of pig manure, which increases the cost of composting and dilutes the N, P and K content in organic fertilizers. In this study, maggot treatment was used in composting instead of bulking agents. In experiment of selecting an optimal inoculum level for composting, the treatment of 0.5% maggot inoculum resulted in the maximum yield of late instar maggots, 11.6% (maggots weight/manure weight). The manure residue became noticeably granular by day 6 and its moisture content was below 60%, which was suitable for further composting without bulking agents. Moreover, in composting experiment with a natural compost without maggot inoculum and maggot-treated compost at 0.5% inoculum level, there were no significant differences in nutrient content between the two organic fertilizers from the two treatments (paired Student's t15=1.0032, P=0.3317). Therefore, maggot culturing did not affect the characteristics of the organic fertilizer. The content of TNPK (total nitrogen+total phosphorus+total potassium) in organic fertilizer from maggot treatment was 10.72% (dry weight), which was far more than that of organic fertilizer made by conventional composting with bulking agents (about 8.0%). Dried maggots as feed meet the national standard (GB/T19164-2003) for commercial fish meal in China, which contained 55.32±1.09% protein; 1.34±0.02% methionine; 4.15±0.10% lysine. This study highlights housefly maggot-treated composting can be considered sustainable alternatives for pig manure management to achieve high-quality organic fertilizer and maggots as feed without bulking agents. © 2014 Elsevier Ltd.


PubMed | Huzhou Hongquan Biotechnology Ltd Company, Work Safety Production Science Research Institute of Zhejiang Province, Hangzhou Meteorological Bureau and Zhejiang Academy of Agricultural Sciences
Type: | Journal: Waste management (New York, N.Y.) | Year: 2014

In traditional composting, large amounts of bulking agents must be added to reduce the moisture of pig manure, which increases the cost of composting and dilutes the N, P and K content in organic fertilizers. In this study, maggot treatment was used in composting instead of bulking agents. In experiment of selecting an optimal inoculum level for composting, the treatment of 0.5% maggot inoculum resulted in the maximum yield of late instar maggots, 11.6% (maggots weight/manure weight). The manure residue became noticeably granular by day 6 and its moisture content was below 60%, which was suitable for further composting without bulking agents. Moreover, in composting experiment with a natural compost without maggot inoculum and maggot-treated compost at 0.5% inoculum level, there were no significant differences in nutrient content between the two organic fertilizers from the two treatments (paired Students t15=1.0032, P=0.3317). Therefore, maggot culturing did not affect the characteristics of the organic fertilizer. The content of TNPK (total nitrogen+total phosphorus+total potassium) in organic fertilizer from maggot treatment was 10.72% (dry weight), which was far more than that of organic fertilizer made by conventional composting with bulking agents (about 8.0%). Dried maggots as feed meet the national standard (GB/T19164-2003) for commercial fish meal in China, which contained 55.32 1.09% protein; 1.34 0.02% methionine; 4.15 0.10% lysine. This study highlights housefly maggot-treated composting can be considered sustainable alternatives for pig manure management to achieve high-quality organic fertilizer and maggots as feed without bulking agents.


Zheng Y.,Nanjing University of Information Science and Technology | Zheng Y.,Chinese Academy of Meteorological Sciences | Che H.,Chinese Academy of Meteorological Sciences | Zhao T.,Nanjing University of Information Science and Technology | And 11 more authors.
Atmosphere | Year: 2016

A special period in Beijing from 6 August to 17 September 2015, during which theWorld Athletics Championships and Victory Day military parade took place, and which involved measures to restrict traffic and reduce factory emissions, was selected to analyze the aerosol optical properties and the impact of meteorological conditions on pollution levels. The study was based on AERONET observational and retrieval data, particulate matter measurements (TEOM 1405), meteorological data, and then the HYSPLIT model was used to analyze the pollution sources. The study period was divided into three sub-periods according to the different stages of implementation of the control measures, and the main conclusions can be summarized as follows. During the period in which the restrictive measures were applied, the air quality improved significantly, with the average value of the AOD being 0.34 ± 0.20, about 69% less than before. Meanwhile, the average Ångström exponent was about 9.5% higher than before, with an average value of 1.38 ± 0.25, indicating that the main pollutants were fine particles. Single scattering albedo decreased as wavelength increased, being higher than in the other two stages (mean value of 0.944 ± 0.045). This showed that the strong scattering capacity and absorption aerosol optical depth was at its lowest, at about 0.008 ± 0.009. The peaks of aerosol volume concentration in the fine and coarse mode were significantly reduced. Meteorological conditions also had a certain effect on the aerosol optical properties, with the blowing of clean and dry wind and the occurrence of precipitation contributing to the overall improvement in air quality. © 2016 by the authors.


Yu B.,Hangzhou Meteorological Bureau | Pan W.-Z.,Hangzhou Meteorological Bureau | Song J.,Hangzhou Meteorological Bureau | Miao Q.-L.,Nanjing University of Information Science and Technology | And 2 more authors.
Yantu Lixue/Rock and Soil Mechanics | Year: 2012

The evidence weights model based on the weights of evidence method was applied to study the zonation of the landslide geohazards in Hangzhou. The main data sources consisted of geological maps, digital elevation model (DEM), land use data and 1905 specical cases of geohazards collected from 1930 to 2009 in Hangzhou city. The evidence factors involve heavy rain, types and structure of rock, slope, slope direction and high slope, river network and Path buffer, which were derived from maps using Arcgis spatial analysis and information extraction. The weights for each evidence map were calculated using the frequency of known landslides in the classes of causative parameters; then the probability of landslide for arbitrary grid was produced by summation of assigned weight values using Arc-WofE extended module, achieving the goal of spatial prediction for potential landslide points. The accuracy verified by the spilt-sample validation method was 88.3%. The obtained results were well coincident with the occurrence of the known landslides in the study area. It is shown that the weights of evidence method could be evaluated objectively and quantitatively for multivariate analysis, as a basis of the choice of factors for landslide geohazards zonation. So the methodology is very useful and accurate, and it is worth popularizing and applying to the risk zonation and evaluation of landslide geohazards.


Xu H.-H.,Zhejiang Meteorological Science Institute | Pu J.-J.,Zhejiang Meteorological Science Institute | He J.,The University of Nottingham Ningbo, China | Liu J.,Zhejiang Meteorological Science Institute | And 2 more authors.
Advances in Meteorology | Year: 2016

In order to understand the formation and evolution of recurrent severe haze pollution episodes in Yangtze River Delta, China, a short comparative sampling campaign was conducted at the Lin'an background monitoring station from 25 November 2013 to 14 December 2013. The characteristic concentrations of PM2.5, black carbon, CO2, CO, and CH4 have been systematically recorded at the abovementioned site. Coupled with detailed analysis of air backward trajectories, fire spot distribution surrounding the studied site and meteorological impacts, temporal trend, diurnal variation, and intercorrelation of the aforementioned species have also been comprehensively investigated throughout prehaze, haze, and posthaze periods. © 2016 Hong-Hui Xu et al.


Qi B.,Hangzhou Meteorological Bureau | Du R.-G.,Hangzhou Meteorological Bureau | Yu Z.-F.,Hangzhou Normal University | Zhou B.,Hangzhou Normal University
Zhongguo Huanjing Kexue/China Environmental Science | Year: 2014

The characteristics of aerosol optical depth (AOD) and Angstrom wavelength exponent (α) were analyzed and compared using Cimel sunphotometer data from 2011 to 2012 at national basic meteorological station in Hangzhou city of China. The results showed that the mean value of AOD500 nm and α440-870 nm were 0.86 ± 0.47 and 1.25 ± 0.23, respectively. The averaged AOD over Hangzhou had no obviously seasonal variation characteristics. It was closely related to the weather patterns and internal and external sources influence in this region. The seasonal variation of α was not distinct. Due to dust aerosol spreading from north of china, the α measured in spring was a little lower compared to other seasons. The diurnal variation of averaged AOD showed a single peak distribution with the peak value and valley value at 15:00 and 06:00 respectively. The significantly increased value of AOD in the afternoon were due to the secondary aerosols generated from photochemical reactions that caused by strongly solar radiations and the aerosols in the surface layer spreading to upper layer influenced by turbulent transfer action. Both the AOD and α showed obvious single peak of frequencies based on the frequency distribution. It was found that the AOD and α can be better characterized by a lognormal distribution. The frequency of α, occurring in the high value range between 1.1and 1.7was 77.8%, which indicated that the average effective radii of aerosol particles were small and the aerosols should be classified as urban-industrial aerosols in Hangzhou. The data also showed high AOD (> 1.0) both clustering in the fine mode growth wing and the coarse mode.


Du R.-G.,Hangzhou Meteorological Bureau | Qi B.,Hangzhou Meteorological Bureau | Zhou B.,Hangzhou Normal University | Yu Z.-F.,Hangzhou Normal University
Zhongguo Huanjing Kexue/China Environmental Science | Year: 2013

The variations of the aerosol absorption coefficient in the urban area of Hangzhou city for the period from April to June, 2011 and from December, 2011 to February 2012, were studied using black carbon and conventional meteorological date at national basic meteorological stations. The results showed that the absorption coefficient in winter [(42.3±17.7)Mm-1] was higher than that in summer [(35.8±10.5)Mm-1] and the aerosol absorption coefficient changed violently in winter. The diurnal variation of the aerosol absorption coefficient presented a double-peak on effects of boundary layer evolution and human activities, the peak value appeared at 07:00~09:00, the valley value appeared at 14:00, the second peak value appeared at 19:00~20:00. The most representative aerosol absorption coefficient was 24.7Mm-1, which was calculated by fitting hourly frequency distribution. Aerosol absorption coefficient in haze was higher than that in no-haze. The increase in haze pollution led to step up trend of aerosol absorption coefficient, which may be one of the important reasons for visibility degradation.

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