With different varieties of facility Hami melon(Cucumis melo var. sacchairinus) as test materials, the effects of meteorological conditions on the yield and quality of different varieties of facility Hami melon were a...With different varieties of facility Hami melon(Cucumis melo var. sacchairinus) as test materials, the effects of meteorological conditions on the yield and quality of different varieties of facility Hami melon were analyzed. The results showed that among the yield and quality traits of melon, the variation degree of average single melon weight was the highest, and the coefficient of variation was 33.05%. The variation degree of leaf area index was the lowest, and the coefficient of variation was 11.00%. Through the correlation analysis of meteorological factors with the yield and quality of facility Hami melon, it was found that the quality traits of facility Hami melon were significantly positively correlated with maximum temperature and sunshine duration, and significantly negatively correlated with precipitation. The yield traits were positively correlated with maximum temperature, sunshine duration and precipitation.展开更多
In order to take advantage of the climate resources more effectively ac- cording to the local circumstances and to plan and develop the citrus industry in Southern Shaanxi more reasonably. On the basis of the investig...In order to take advantage of the climate resources more effectively ac- cording to the local circumstances and to plan and develop the citrus industry in Southern Shaanxi more reasonably. On the basis of the investigation of freeze dam- age to citrus occurring in Southern Shaanxi in the winter of 2010, the climatic back- ground for the formation of this freeze damage was analyzed. In combination with the freeze damage indicators during the overwintering period and the harmful accu- mulated cold during the cold wave, indexes for grading the freeze damage in southern Shaanxi were analyzed and verified, and the perspective of grading the freeze damage using the harmful accumulated cold during the cold wave was also presented. Through analyzing the extremely lowest temperature and the harmful ac- cumulated cold in the winter of 2010 and in history at 12 citrus growing counties (districts) in Ankang area and Hanzhong area, the reasons why the freeze damage to citrus during the overwintering period was severer in the west than in the east of Southern Shaanxi were discussed, and the results obtained were basically consistent with the actual situation observed from investigation. Finally, defensive countermea- sures against the freeze damage to citrus during the overwintering period were put forward from several aspects.展开更多
Osmanthus, an ornamental plants, is favored by people, and forecast of Osmanthus florescence is of vital significance for enjoying the sight. Based on 15 years of flowering observation data, analysis was made on agric...Osmanthus, an ornamental plants, is favored by people, and forecast of Osmanthus florescence is of vital significance for enjoying the sight. Based on 15 years of flowering observation data, analysis was made on agricultural meteorologi- cal conditions of Osmanthus in Guilin and the results showed that ground tempera- ture, humidity, precipitation, sunshine have significant effects on Osmanthus flores- cence. In forecasting florescence, therefore, it is necessary to take comprehensive consideration of weather conditions and changes in the future, to release Osman- thus flowering forecast as per method of combination of long-term forecasting and short-term forecast.展开更多
By comparative analysis on the meteorological conditions and occurrences of rice planthoppers in Guilin of Guangxi during recent 5 years,the temperature,precipitation,wind direction,wind velocity,humidity were chosen ...By comparative analysis on the meteorological conditions and occurrences of rice planthoppers in Guilin of Guangxi during recent 5 years,the temperature,precipitation,wind direction,wind velocity,humidity were chosen as the factors that affected the migration of rice planthopper in Guilin.Thinking of meteorological conditions and injurious number in early period,regression analysis method was used to establish the work system for grade forecast of meteorological conditions that affected the migration of rice planthopper.The forecast factors and targets were divided as 5 grades in the work system.Using one-week's weather forecast conclusion that local observatory had published,whether the meteorological conditions and injurious number were favorable or not was analyzed synthetically.The meteorological conditions grades that affected the migration of rice planthopper for each day in future 1-7 days were predicted.This is a practical forecast work system and the forecast accuracy for each day is larger than 70%.The work system has positive function in the manufacture practice.展开更多
Based on the data of 18 cases during the past 30 years from 1978 to 2007,the major meteorological conditions for outbreak of blue-green alga in Hongze Lake were analyzed.The results showed that the main meteorological...Based on the data of 18 cases during the past 30 years from 1978 to 2007,the major meteorological conditions for outbreak of blue-green alga in Hongze Lake were analyzed.The results showed that the main meteorological conditions that affected the production and outbreak of blue-green alga were unusual high monthly average temperature,less precipitation and more sunshine hours in ten days.Through the selection of 1 or 0 factors on the values of above meteorological conditions over the years,if the conditions were accorded with the outbreak of blue-green alga,the factor was signed as 1,or it would be signed as 0;if there was outbreak of blue-green alga within ten days,it was signed as 1,or it would be signed as 0;crossing interrelated and integrated prediction method was adopted to establish the prediction equation for outbreak of blue-green alga,the historical fitting rate was 87.5%,and the predicting accuracy rate in 2008-2009 was 87.5%.In addition to meteorological conditions,outbreak of blue-green alga was also influenced by industrial pollutions,etc.,which should be considered in the forecasting procedures.展开更多
Urban areas face significant challenges in maintaining water quality amidst increasing urbanization and changing climatic patterns. This study investigates the complex interplay between meteorological variables and wa...Urban areas face significant challenges in maintaining water quality amidst increasing urbanization and changing climatic patterns. This study investigates the complex interplay between meteorological variables and water quality parameters in Nairobi City, focusing on the impacts of rainfall and temperature on surface water quality. Data from multiple sources, including the Water Resources Authority, Nairobi Water and Sewerage Company, and the World Bank’s Climate Change Knowledge Portal, were analyzed to assess the relationships between meteorological variables (rainfall and temperature) and water quality parameters (such as electroconductivity, biochemical oxygen demand, chloride, and pH). The analysis reveals varying impacts of rainfall and temperature on different water quality parameters. While parameters like iron and pH show strong relationships with both rainfall and temperature, others such as ammonia and nitrate exhibit moderate relationships. Additionally, the study highlights the influence of runoff, urbanization, and industrial activities on water quality, emphasizing the need for holistic management approaches. Recommendations encompass the establishment of annual publications on Nairobi River water quality, online accessibility of water quality data, development of hydrological models, spatial analysis, and fostering cross-disciplinary research collaborations. Implementing these recommendations can enhance water quality management practices, mitigate risks, and safeguard environmental integrity in Nairobi City.展开更多
Guilin sugar orange has advantages of good taste, harvest during the Spring Festival, marketable market, and it has got swift and violent development in recent years. Sugar orange yield and quality is closely related ...Guilin sugar orange has advantages of good taste, harvest during the Spring Festival, marketable market, and it has got swift and violent development in recent years. Sugar orange yield and quality is closely related to meteorological conditions, so in order to study the effect of meteorological conditions on the Guilin sugar orange, the local conditions of each orange-planting county in Guilin is analyzed, and study is also carried out on the severe weather and its defense measures. The suitable growth temperature for sugar orange is 23-29 ℃, and sugar orange is not tolerant to waterlogging and drought, like light, and has no resistance to ice cold. The main meteorological disasters include high temperature, low temperature, flood, drought, wind, hail, etc. Reasonable selection of orchard, scientific management, especially the management of plant diseases and insect pests, is the key to ensure high-quality high sand sugar orange.展开更多
The recent year's monitor results of Beijing indicated that the pollution level of fine particles PM 2.5 showed an increasing trend. To understand pollution characteristics of PM 2.5 and its relationship...The recent year's monitor results of Beijing indicated that the pollution level of fine particles PM 2.5 showed an increasing trend. To understand pollution characteristics of PM 2.5 and its relationship with the meteorological conditions in Beijing, a one-year monitoring of PM 2.5 mass concentration and correspondent meteorological parameters was performed in Beijing in 2001. The PM 2.5 levels in Beijing were very high, the annual average PM 2.5 concentration in 2001 was 7 times of the National Ambient Air Quality Standards proposed by US EPA. The major chemical compositions were organics, sulfate, crustals and nitrate. It was found that the mass concentrations of PM 2.5 were influenced by meteorological conditions. The correlation between the mass concentrations of PM 2.5 and the relative humidity was found. And the correlation became closer at higher relative humidity. And the mass concentrations of PM 2.5 were negtive-correlated to wind speeds, but the correlation between the mass concentration of PM 2.5 and wind speed was not good at stronger wind.展开更多
[Objective] The paper was to understand the suitable meteorological indexes and key meteorological factors for infection and prevalence of tobacco brown spot. [ Method] Tobacco brown spot disease in five topical mount...[Objective] The paper was to understand the suitable meteorological indexes and key meteorological factors for infection and prevalence of tobacco brown spot. [ Method] Tobacco brown spot disease in five topical mountainous climatic areas of Guizhou Province was investigated, and the difference of biological characteristics of different strains was analyzed indoor. Different meteorological conditions (light, temperature and humidity) were simulated in artificial climate box by using the uniform design method, and the difference of infection ability of Alternaria alternate in different climate zones was analyzed in leaves in vitro by hanging drop method. [ Result] The infection rate of A. alternate in different climate zones of Guizhou Province showed certain difference. In low temperature and mid- die humidity (the humidity is 50% -60%, the temperature is 10 -20 ℃) conditions, the pathogen could infect tobacco leaves, various strains had certain difference, but the difference was small. [ Conclusion] The paper provided theoretical basis for prevalence prediction and control of tobacco brown spot.展开更多
The impacts of the meteorological condition and emissions reduction on the aerosol concentration over the Beijing-Tianjin-Hebei(BTH) region during the COVID-19 lockdown were analyzed by conducting three numerical expe...The impacts of the meteorological condition and emissions reduction on the aerosol concentration over the Beijing-Tianjin-Hebei(BTH) region during the COVID-19 lockdown were analyzed by conducting three numerical experiments,including one with the meteorological field in 2019 and MEIC-2019(2019 monthly Multi-resolution Emissions Inventory for China),one with the meteorological field in 2020 and MEIC-2019,and one with the meteorological field in 2020 and MEIC-2020,via a WRF-Chem model.The numerical experiments were performed from 3 to 16 February in 2019 and in 2020,during which a severe fog-haze event(3-16 February 2020) occurred in the BTH region,with a simulated maximum daily PM2.5 of 245μg m-3 in Tangshan and 175μg m-3 in Beijing.The results indicate that the daily PM2.5 decreased by 5-150μg m-3 due to the emissions reduction and increased by 10-175 μg m-3 due to the meteorological condition in Beijing,Shijiazhuang,Cangzhou,Handan,Hengshui,Chengde,Zhangjiakou,and Tangshan from 7 to 14 February.For the horizontal distribution,PM2.5 and different aerosol species concentrations from 7 to 14 February 2020 increased compared with those during the same period in 2019,indicating that the accumulation of pollutants caused by the unfavorable meteorological condition offset the decreases caused by the emissions reduction,leading to the high aerosol concentration during the COVID-19 lockdown.展开更多
[Objective] The study aimed to discuss the relationship of cardiovascular and cerebrovascular diseases to meteorological conditions and forecast method in Nanjing City. [Method] Based on daily cases of cardiovascular ...[Objective] The study aimed to discuss the relationship of cardiovascular and cerebrovascular diseases to meteorological conditions and forecast method in Nanjing City. [Method] Based on daily cases of cardiovascular and cerebrovascular diseases from a hospital in Nanjing City as well as daily meteorological data from Nanjing Meteorological Station from January 2003 to July 2008, the monthly and seasonal variations in quantity of patients suffedng from cardiovascular and cerebrovascular diseases in Nanjing City were analyzed firstly, and then the relationship between mete- orological elements and incidence of the diseases was discussed, finally the forecast model for the incidence of the diseases was established using the stepwise regression method. [Result] Cardiovascular and cerebrovascular diseases in Nanjing City happened all the year round, and the inci- dance was high in the seasonal transition phase from autumn to winter. Daily incidence of the diseases in Nanjing City correlated negatively with dai- ly maximum, minimum and average vapor pressure, daily minimum relative humidity and so forth, but their incidence had positive correlations with diumal range of daily temperature, daily maximum, minimum and average pressure. Daily average number of patients suffering from the diseases obviously correlated with daily average temperature, daily maximum vapor pressure and daily average relative humidity. [ Conclusion] The research could provide scientific references for the prevention and forecast of cardiovascular and cerebrovascular diseases in future.展开更多
This work analyzes and discusses the influence of human activities on the meteorological conditions related to winter haze events in Beijing,Tianjin,and Hebei(i.e.,the Jing-Jin-Ji region)during 1961-2016,using the res...This work analyzes and discusses the influence of human activities on the meteorological conditions related to winter haze events in Beijing,Tianjin,and Hebei(i.e.,the Jing-Jin-Ji region)during 1961-2016,using the results of two numerical simulation experiments based on the Community Atmosphere Model version 5.1.1(http://www.cesm.ucar.edu/models/cesm1.0/cam/docs/ug5_1_1/book1.html)used in the international Climate Variability and Predictability Programme(CLIVAR)Climate of the 20th Century Detection and Attribution Project(C20C+D&A).The results show that,under the influence of human activities,the changes in dynamical and thermal meteorological conditions related to winter haze events in the Jing–Jin–Ji region are conducive to the formation and accumulation of haze,and prevent the diffusion of pollutants.The dynamical conditions mainly include the obvious weakening of the East Asian winter monsoon(EAWM)and the enhancement of the near-surface anomalous southerly wind.The thermal conditions include the obvious increase in surface temperature,and the enhancement of water vapor transport and near-surface inversion.The relative contribution of dynamical and thermal conditions to the variation of haze days in the Jing-Jin-Ji region is analyzed using statistical methods.The results show that the contribution of human activities to the increase of haze days in the Jing-Jin-Ji region is greater than that of natural forcing for the study period.To be specific,the dynamical meteorological factors contribute more to the haze days than the thermal meteorological factors.The contribution of thermal meteorological factors is basically the same in both scenarios.展开更多
Through observing the phenology of two kinds of fruit trees,apple and peach trees,during their flowering periods in the past seven years,the meteorological conditions in the flowering stages were analyzed and summariz...Through observing the phenology of two kinds of fruit trees,apple and peach trees,during their flowering periods in the past seven years,the meteorological conditions in the flowering stages were analyzed and summarized in this paper.The late frost weather situation occurred in late April in Haiyang City also was elaborated in the paper.According to the data analysis,the terrain effect had induced a large temperature differences between north and south in April in Haiyang.Early flowering of fruit trees is as early as 5 to 8 days in the northern region than that in the southern region;accumulated temperature which was greater than or equal to 0 ℃ and the date of the temperature stably through a boundary,were the important meteorological indicators of the fruit trees' early flowering.The late frost in mid-late April is meteorological disasters of the fruit trees flowering period.The weather background of the occurred late frost,the disaster reasons and the measures for the prevention of late frost were proposed.展开更多
[Objective] The research aimed to study statistical forecast method for O3 concentration near the ground in Pudong District of Shanghai based on meteorological condition analysis. [Method] Via observation and statisti...[Objective] The research aimed to study statistical forecast method for O3 concentration near the ground in Pudong District of Shanghai based on meteorological condition analysis. [Method] Via observation and statistical analysis of the O3 concentration near the ground in Pudong District of Shanghai from 2006 to 2008, by considering meteorological condition, a kind of simple and practical new method suiting for forecast of the O3 concentration and pre-warning of the high-concentration O3 pollution event in whole year was established. [Result] Meteorological condition had obvious influence on O3 concentration near the ground. O3 concentration was the biggest in sunny day, followed by cloudy day. O3 concentration near the ground had typical seasonal change characteristics, and high value mainly happened in summer. Meteorological condition generating high-concentration O3 included sunny day, strong UV radiation, low relative humidity, high temperature and small wind speed, etc. By surveying historical weather chart, 10 kinds of main weather situations affecting Shanghai were summed. Under each weather situation, occurrence probability of the high-concentration O3 near the ground and average O3 concentration were conducted statistics. We found that occurrence probability of the high-concentration O3 was the biggest under northwest side of the subtropical high type, followed by internal type of the subtropical high. By introducing HPPI and WDI and comprehensively considering various meteorological factors, forecasting equation of the O3 concentration was established based on stepwise regression. The equation had good fitting effect and predictability on the daily maximum O3 concentration. [Conclusion] The method also could provide reference for O3 forecast in other areas.展开更多
[ Objective] The study aimed to analyze the spatial distribution of agricultural meteorological conditions in Sanjiang Plain during nearly 50 years. [ Method] Accumulated temperature of Sanjiang Plain was computed bas...[ Objective] The study aimed to analyze the spatial distribution of agricultural meteorological conditions in Sanjiang Plain during nearly 50 years. [ Method] Accumulated temperature of Sanjiang Plain was computed based on meteorological observation data from different meteorological stations in Sanjiang Plain, including temperature, precipitation, sunshine time, etc. A spatial interpolation map involving varieties of meteorological elements in neady 50 years was generated based on the Kriging interpolation, and the spatial distribution characteristics of those meteorological ele- ments were analyzed. [ Result] Temperature of Sanjiang Plain decreased with the increase of latitude and altitude, and the annual average temper- atura varied from 2.5 to 4.5 ~(3 generally, showing a zonal distribution. Precipitation of Sanjiang Plain changed spatially and the annual average pre- cipitation varied from 500 to 600 mm symmetrically in northwest-southeast direction. Spatial distribution of the annual average wind speed in San- jiang Plain was identical with the spatial pattern of topography here, and the annual average wind speed changed from 3.0 to 3.6 rn/s in most re- gions. Relative air humidity of Sanjiang Plain in summer half year was relatively high and always above 65%. The maximum sunshine hours of San- jiang Plain in one year distributed similarly to the annual changing curve of solar declination, and both of them presented a normal distribution and changed with geographic latitude. The days from the beginning to the end of daily average temperature ~〉 10 ~C in Sanjiang Plain were 135 -146 d, and its distribution presented a latitudinal trend, with certain vertical zonality. [ Conclusion] The research could provide scientific references for the reasonable arrangement of agricultural production and effective prevention of meteorological disasters in Sanjiang Plain.展开更多
1 INTRODUCTION Meteorological factors, especially precipitation, have close links with geological calamities. According to the statistics, more than 70% of the geological calamities in China occur in rainy seasons. Ma...1 INTRODUCTION Meteorological factors, especially precipitation, have close links with geological calamities. According to the statistics, more than 70% of the geological calamities in China occur in rainy seasons. Many researchers are thus motivated to study extensively to determine their relationship in the prediction of geological calamltles . They either rely on single measurements of rainfall to seek basis for widespread occurrence of geological calamities or treat antecedent diurnal rainfall with equal importance, though with account of the accumulated effect of preceding rainfall. Furthermore, it is common for quite a number of models to use the rainfall recorded at hydrological or meteorological rain gauges as the one for the interested day, reducing the time validity of the prediction. In our analysis, it is found that the landslides and debris flows in Zhejiang province are related with the antecedent precipitation (but not by a simple accumulation). Critical amounts of accumulated and effective rainfall are used in this work to tell whether there will be geological calamities. Moreover, MM5 is used to forecast rainfall, taking account in equations of the predictand for landslides and debris flows, in attempts to predict the appearance of meteorological condition for geological calamities and improve the rationality of forecasting procedures and time validity of forecasts.展开更多
Strategic maintenance plays a key role in ensuring high availability and utilization of the haul trucks,and as equipment began to grow more complex towards the end of the 20th century,there was a need for a proactive ...Strategic maintenance plays a key role in ensuring high availability and utilization of the haul trucks,and as equipment began to grow more complex towards the end of the 20th century,there was a need for a proactive maintenance strategy,which led to the development of condition-based maintenance.Realtime condition monitoring(RTCM)is the ability to perform condition monitoring in real-time and has the ability to alert maintenance and operations of abnormal conditions.These alarms can be used as an indication leading to a problem,and if a suitable corrective action is initiated in time,it could result in significant savings of equipment downtime and repair costs.This study aims to compare some maintenance performance indicators prior to and after implementation of RTCM strategy at a mine site using some tests of statistical significance.The study also indicated the presence of seasonality in the data,and thus the data was deseasonalized and detrended prior to being subjected to the statistical tests.Finally,the results indicated that RTCM strategy has proven to be successful in improving the availability for some of the failure categories chosen in this study.展开更多
Objective To investigate the impact of meteorological conditions and PM2.5 on the onset of acute aortic dissection in monsoonal climate. Methods A linear regression analysis was performed in monsoonal climate epidemio...Objective To investigate the impact of meteorological conditions and PM2.5 on the onset of acute aortic dissection in monsoonal climate. Methods A linear regression analysis was performed in monsoonal climate epidemiological survey for a period of four years on the impact of meteorological factors (minimal temperature, mean temperature, maximal temperature, average daily surface temperature, day temperature range, relative humidity, mean wind speed, and atmospheric pressure) and PM2.5 concentration on the daily incidences of acute aortic dissections. Meteorological variables and PM2.5 concentration were retrieved on a daily basis from Beijing Regional Climate Center and the Ministry of Environmental Protection of the People’s Republic of China’s website, and the daily incidences of acute aortic dissections were retrieved from the Clinical Data Analysis and Reporting System in the Emergency and Critical Care Center of Beijing Anzhen Hospital. Results During the study period (from January 2011 to December 2014), 1164 patients were identified as having acute aortic dissections. The corresponding incidences in spring and autumn were 0.96 and 1.00, respectively, which significantly higher than that in summer and winter. The incidences of acute aortic dissection in a day could be predicted by diurnal temperature range (DTR) using the following linear multiple regression models: incidences of acute aortic dissection = 0.543 + 0.025 × DTR. Conclusion This is the first study to show an attributable effect of DTR on acute aortic events in monsoonal climate. Our study confirms that meteorological variables were important factors influencing the incidence of acute aortic dissection.展开更多
Based on the real-time wind direction and speed data from an automatic meteorological monitoring network in Shenzhen, the wind characteristics of Jue Diao Sha maritime area are analyzed. As indicated in the results, t...Based on the real-time wind direction and speed data from an automatic meteorological monitoring network in Shenzhen, the wind characteristics of Jue Diao Sha maritime area are analyzed. As indicated in the results, the wind speed of this area is higher than that over the land, the average wind speed is above 3 m/s and the probability for the maximum wind speed to drop below 20 m/s is above 90%. Moreover, the probability for the hourly swing angle of wind direction to become less than 50o is above 80%, suggesting that the wind conditions in the Jue Diao Sha area could meet the requirements of the sporting events. According to the numerical simulation, this area is the best selected site among three candidates. Furthermore, the characteristics of daily land and sea breezes are such that it is suggested the game will be best carried out from 1000 to 1700 Beijing Standard Time.展开更多
To reveal the multivariate relationships between man-made and meteorological factors on dust storm frequency, the LUCC data, NDVI remote sensing data and meteorological data for the period of 1983-2013 were combined w...To reveal the multivariate relationships between man-made and meteorological factors on dust storm frequency, the LUCC data, NDVI remote sensing data and meteorological data for the period of 1983-2013 were combined with dust storm frequency data, and the possible impacts of meteorological and anthropogenic factors on dust storm frequency were analyzed by using regression analysis and PCA (Principal Component Analysis). Results show that the inter-annual dust storm frequency increased gradually. In particular, an increasing trend in recent years, after 2009, is conspicuous. The monthly frequency of dust storms shows higher values between the months of February and May, with the highest mean number of events occurring in April, which accounts for 29% of the annual dust storm frequency. The annual dust storm frequency is positively correlated with wind speed and negatively correlated with precipitation;the monthly dust storm frequency is positively correlated with wind speed, but no significant correlation can be found with precipitation. The relationship between temperature and dust storms is not simply linear, however, a certain correlation with an unremarkable statistical significance can be found between them. Human activities also affect the dynamics of dust storms indirectly via changing vegetation coverage and direct dust emissions. The multivariate analysis further confirmed the association between dust storm frequency and meteorological factors and NDVI. The high loadings of dust storm frequency, wind speed, precipitation and NDVI on a PC indicate that the increased precipitation and NDVI will decrease dust storm frequency, and increased wind speed will increase dust storm frequency.展开更多
基金Supported by Project of Shandong Institute of Modern Agriculture of Zhejiang University for Serving Local Economic Development (ZDNY-2020-FWLY2006)。
文摘With different varieties of facility Hami melon(Cucumis melo var. sacchairinus) as test materials, the effects of meteorological conditions on the yield and quality of different varieties of facility Hami melon were analyzed. The results showed that among the yield and quality traits of melon, the variation degree of average single melon weight was the highest, and the coefficient of variation was 33.05%. The variation degree of leaf area index was the lowest, and the coefficient of variation was 11.00%. Through the correlation analysis of meteorological factors with the yield and quality of facility Hami melon, it was found that the quality traits of facility Hami melon were significantly positively correlated with maximum temperature and sunshine duration, and significantly negatively correlated with precipitation. The yield traits were positively correlated with maximum temperature, sunshine duration and precipitation.
基金Supported by Shaanxi"13115"Public Service Platform Construction Program for Science&Technology Innovation Projects(2010FWPT-17)~~
文摘In order to take advantage of the climate resources more effectively ac- cording to the local circumstances and to plan and develop the citrus industry in Southern Shaanxi more reasonably. On the basis of the investigation of freeze dam- age to citrus occurring in Southern Shaanxi in the winter of 2010, the climatic back- ground for the formation of this freeze damage was analyzed. In combination with the freeze damage indicators during the overwintering period and the harmful accu- mulated cold during the cold wave, indexes for grading the freeze damage in southern Shaanxi were analyzed and verified, and the perspective of grading the freeze damage using the harmful accumulated cold during the cold wave was also presented. Through analyzing the extremely lowest temperature and the harmful ac- cumulated cold in the winter of 2010 and in history at 12 citrus growing counties (districts) in Ankang area and Hanzhong area, the reasons why the freeze damage to citrus during the overwintering period was severer in the west than in the east of Southern Shaanxi were discussed, and the results obtained were basically consistent with the actual situation observed from investigation. Finally, defensive countermea- sures against the freeze damage to citrus during the overwintering period were put forward from several aspects.
文摘Osmanthus, an ornamental plants, is favored by people, and forecast of Osmanthus florescence is of vital significance for enjoying the sight. Based on 15 years of flowering observation data, analysis was made on agricultural meteorologi- cal conditions of Osmanthus in Guilin and the results showed that ground tempera- ture, humidity, precipitation, sunshine have significant effects on Osmanthus flores- cence. In forecasting florescence, therefore, it is necessary to take comprehensive consideration of weather conditions and changes in the future, to release Osman- thus flowering forecast as per method of combination of long-term forecasting and short-term forecast.
基金Supported by The Project of Guilin Science and Technology in Guangxi (2009011405)
文摘By comparative analysis on the meteorological conditions and occurrences of rice planthoppers in Guilin of Guangxi during recent 5 years,the temperature,precipitation,wind direction,wind velocity,humidity were chosen as the factors that affected the migration of rice planthopper in Guilin.Thinking of meteorological conditions and injurious number in early period,regression analysis method was used to establish the work system for grade forecast of meteorological conditions that affected the migration of rice planthopper.The forecast factors and targets were divided as 5 grades in the work system.Using one-week's weather forecast conclusion that local observatory had published,whether the meteorological conditions and injurious number were favorable or not was analyzed synthetically.The meteorological conditions grades that affected the migration of rice planthopper for each day in future 1-7 days were predicted.This is a practical forecast work system and the forecast accuracy for each day is larger than 70%.The work system has positive function in the manufacture practice.
文摘Based on the data of 18 cases during the past 30 years from 1978 to 2007,the major meteorological conditions for outbreak of blue-green alga in Hongze Lake were analyzed.The results showed that the main meteorological conditions that affected the production and outbreak of blue-green alga were unusual high monthly average temperature,less precipitation and more sunshine hours in ten days.Through the selection of 1 or 0 factors on the values of above meteorological conditions over the years,if the conditions were accorded with the outbreak of blue-green alga,the factor was signed as 1,or it would be signed as 0;if there was outbreak of blue-green alga within ten days,it was signed as 1,or it would be signed as 0;crossing interrelated and integrated prediction method was adopted to establish the prediction equation for outbreak of blue-green alga,the historical fitting rate was 87.5%,and the predicting accuracy rate in 2008-2009 was 87.5%.In addition to meteorological conditions,outbreak of blue-green alga was also influenced by industrial pollutions,etc.,which should be considered in the forecasting procedures.
文摘Urban areas face significant challenges in maintaining water quality amidst increasing urbanization and changing climatic patterns. This study investigates the complex interplay between meteorological variables and water quality parameters in Nairobi City, focusing on the impacts of rainfall and temperature on surface water quality. Data from multiple sources, including the Water Resources Authority, Nairobi Water and Sewerage Company, and the World Bank’s Climate Change Knowledge Portal, were analyzed to assess the relationships between meteorological variables (rainfall and temperature) and water quality parameters (such as electroconductivity, biochemical oxygen demand, chloride, and pH). The analysis reveals varying impacts of rainfall and temperature on different water quality parameters. While parameters like iron and pH show strong relationships with both rainfall and temperature, others such as ammonia and nitrate exhibit moderate relationships. Additionally, the study highlights the influence of runoff, urbanization, and industrial activities on water quality, emphasizing the need for holistic management approaches. Recommendations encompass the establishment of annual publications on Nairobi River water quality, online accessibility of water quality data, development of hydrological models, spatial analysis, and fostering cross-disciplinary research collaborations. Implementing these recommendations can enhance water quality management practices, mitigate risks, and safeguard environmental integrity in Nairobi City.
文摘Guilin sugar orange has advantages of good taste, harvest during the Spring Festival, marketable market, and it has got swift and violent development in recent years. Sugar orange yield and quality is closely related to meteorological conditions, so in order to study the effect of meteorological conditions on the Guilin sugar orange, the local conditions of each orange-planting county in Guilin is analyzed, and study is also carried out on the severe weather and its defense measures. The suitable growth temperature for sugar orange is 23-29 ℃, and sugar orange is not tolerant to waterlogging and drought, like light, and has no resistance to ice cold. The main meteorological disasters include high temperature, low temperature, flood, drought, wind, hail, etc. Reasonable selection of orchard, scientific management, especially the management of plant diseases and insect pests, is the key to ensure high-quality high sand sugar orange.
文摘The recent year's monitor results of Beijing indicated that the pollution level of fine particles PM 2.5 showed an increasing trend. To understand pollution characteristics of PM 2.5 and its relationship with the meteorological conditions in Beijing, a one-year monitoring of PM 2.5 mass concentration and correspondent meteorological parameters was performed in Beijing in 2001. The PM 2.5 levels in Beijing were very high, the annual average PM 2.5 concentration in 2001 was 7 times of the National Ambient Air Quality Standards proposed by US EPA. The major chemical compositions were organics, sulfate, crustals and nitrate. It was found that the mass concentrations of PM 2.5 were influenced by meteorological conditions. The correlation between the mass concentrations of PM 2.5 and the relative humidity was found. And the correlation became closer at higher relative humidity. And the mass concentrations of PM 2.5 were negtive-correlated to wind speeds, but the correlation between the mass concentration of PM 2.5 and wind speed was not good at stronger wind.
基金Supported by Major Special Project of Guizhou Branch([2011] No.6003)National Natural Science Foundation of China (41040039)
文摘[Objective] The paper was to understand the suitable meteorological indexes and key meteorological factors for infection and prevalence of tobacco brown spot. [ Method] Tobacco brown spot disease in five topical mountainous climatic areas of Guizhou Province was investigated, and the difference of biological characteristics of different strains was analyzed indoor. Different meteorological conditions (light, temperature and humidity) were simulated in artificial climate box by using the uniform design method, and the difference of infection ability of Alternaria alternate in different climate zones was analyzed in leaves in vitro by hanging drop method. [ Result] The infection rate of A. alternate in different climate zones of Guizhou Province showed certain difference. In low temperature and mid- die humidity (the humidity is 50% -60%, the temperature is 10 -20 ℃) conditions, the pathogen could infect tobacco leaves, various strains had certain difference, but the difference was small. [ Conclusion] The paper provided theoretical basis for prevalence prediction and control of tobacco brown spot.
基金This study was supported by the National Key R&D Program of China[grant number 2017YFB0503901)the National Natural Science Foundation of China[grant numbers 41830109 and 41830966]the Major Scientific and Technological Innovation Projects of Shandong Province[grant number 2018YFJH0901].
文摘The impacts of the meteorological condition and emissions reduction on the aerosol concentration over the Beijing-Tianjin-Hebei(BTH) region during the COVID-19 lockdown were analyzed by conducting three numerical experiments,including one with the meteorological field in 2019 and MEIC-2019(2019 monthly Multi-resolution Emissions Inventory for China),one with the meteorological field in 2020 and MEIC-2019,and one with the meteorological field in 2020 and MEIC-2020,via a WRF-Chem model.The numerical experiments were performed from 3 to 16 February in 2019 and in 2020,during which a severe fog-haze event(3-16 February 2020) occurred in the BTH region,with a simulated maximum daily PM2.5 of 245μg m-3 in Tangshan and 175μg m-3 in Beijing.The results indicate that the daily PM2.5 decreased by 5-150μg m-3 due to the emissions reduction and increased by 10-175 μg m-3 due to the meteorological condition in Beijing,Shijiazhuang,Cangzhou,Handan,Hengshui,Chengde,Zhangjiakou,and Tangshan from 7 to 14 February.For the horizontal distribution,PM2.5 and different aerosol species concentrations from 7 to 14 February 2020 increased compared with those during the same period in 2019,indicating that the accumulation of pollutants caused by the unfavorable meteorological condition offset the decreases caused by the emissions reduction,leading to the high aerosol concentration during the COVID-19 lockdown.
基金Supported by the"Meteorology and Health"Subject of Shanghai Science and Technology Committee(QXJK201214)
文摘[Objective] The study aimed to discuss the relationship of cardiovascular and cerebrovascular diseases to meteorological conditions and forecast method in Nanjing City. [Method] Based on daily cases of cardiovascular and cerebrovascular diseases from a hospital in Nanjing City as well as daily meteorological data from Nanjing Meteorological Station from January 2003 to July 2008, the monthly and seasonal variations in quantity of patients suffedng from cardiovascular and cerebrovascular diseases in Nanjing City were analyzed firstly, and then the relationship between mete- orological elements and incidence of the diseases was discussed, finally the forecast model for the incidence of the diseases was established using the stepwise regression method. [Result] Cardiovascular and cerebrovascular diseases in Nanjing City happened all the year round, and the inci- dance was high in the seasonal transition phase from autumn to winter. Daily incidence of the diseases in Nanjing City correlated negatively with dai- ly maximum, minimum and average vapor pressure, daily minimum relative humidity and so forth, but their incidence had positive correlations with diumal range of daily temperature, daily maximum, minimum and average pressure. Daily average number of patients suffering from the diseases obviously correlated with daily average temperature, daily maximum vapor pressure and daily average relative humidity. [ Conclusion] The research could provide scientific references for the prevention and forecast of cardiovascular and cerebrovascular diseases in future.
基金This study was jointly supported by the National Key Research and Development Program of China(2017YF0603703 and 2017YF0605004)the Atmospheric Pollution Control of the Prime Minister Fund of China(DQGG0104).
文摘This work analyzes and discusses the influence of human activities on the meteorological conditions related to winter haze events in Beijing,Tianjin,and Hebei(i.e.,the Jing-Jin-Ji region)during 1961-2016,using the results of two numerical simulation experiments based on the Community Atmosphere Model version 5.1.1(http://www.cesm.ucar.edu/models/cesm1.0/cam/docs/ug5_1_1/book1.html)used in the international Climate Variability and Predictability Programme(CLIVAR)Climate of the 20th Century Detection and Attribution Project(C20C+D&A).The results show that,under the influence of human activities,the changes in dynamical and thermal meteorological conditions related to winter haze events in the Jing–Jin–Ji region are conducive to the formation and accumulation of haze,and prevent the diffusion of pollutants.The dynamical conditions mainly include the obvious weakening of the East Asian winter monsoon(EAWM)and the enhancement of the near-surface anomalous southerly wind.The thermal conditions include the obvious increase in surface temperature,and the enhancement of water vapor transport and near-surface inversion.The relative contribution of dynamical and thermal conditions to the variation of haze days in the Jing-Jin-Ji region is analyzed using statistical methods.The results show that the contribution of human activities to the increase of haze days in the Jing-Jin-Ji region is greater than that of natural forcing for the study period.To be specific,the dynamical meteorological factors contribute more to the haze days than the thermal meteorological factors.The contribution of thermal meteorological factors is basically the same in both scenarios.
文摘Through observing the phenology of two kinds of fruit trees,apple and peach trees,during their flowering periods in the past seven years,the meteorological conditions in the flowering stages were analyzed and summarized in this paper.The late frost weather situation occurred in late April in Haiyang City also was elaborated in the paper.According to the data analysis,the terrain effect had induced a large temperature differences between north and south in April in Haiyang.Early flowering of fruit trees is as early as 5 to 8 days in the northern region than that in the southern region;accumulated temperature which was greater than or equal to 0 ℃ and the date of the temperature stably through a boundary,were the important meteorological indicators of the fruit trees' early flowering.The late frost in mid-late April is meteorological disasters of the fruit trees flowering period.The weather background of the occurred late frost,the disaster reasons and the measures for the prevention of late frost were proposed.
基金Supported by Special Item of the Science Research for Public Service Industry (Meteorology) ,China (GYHY201206027,GYHY200906026)
文摘[Objective] The research aimed to study statistical forecast method for O3 concentration near the ground in Pudong District of Shanghai based on meteorological condition analysis. [Method] Via observation and statistical analysis of the O3 concentration near the ground in Pudong District of Shanghai from 2006 to 2008, by considering meteorological condition, a kind of simple and practical new method suiting for forecast of the O3 concentration and pre-warning of the high-concentration O3 pollution event in whole year was established. [Result] Meteorological condition had obvious influence on O3 concentration near the ground. O3 concentration was the biggest in sunny day, followed by cloudy day. O3 concentration near the ground had typical seasonal change characteristics, and high value mainly happened in summer. Meteorological condition generating high-concentration O3 included sunny day, strong UV radiation, low relative humidity, high temperature and small wind speed, etc. By surveying historical weather chart, 10 kinds of main weather situations affecting Shanghai were summed. Under each weather situation, occurrence probability of the high-concentration O3 near the ground and average O3 concentration were conducted statistics. We found that occurrence probability of the high-concentration O3 was the biggest under northwest side of the subtropical high type, followed by internal type of the subtropical high. By introducing HPPI and WDI and comprehensively considering various meteorological factors, forecasting equation of the O3 concentration was established based on stepwise regression. The equation had good fitting effect and predictability on the daily maximum O3 concentration. [Conclusion] The method also could provide reference for O3 forecast in other areas.
文摘[ Objective] The study aimed to analyze the spatial distribution of agricultural meteorological conditions in Sanjiang Plain during nearly 50 years. [ Method] Accumulated temperature of Sanjiang Plain was computed based on meteorological observation data from different meteorological stations in Sanjiang Plain, including temperature, precipitation, sunshine time, etc. A spatial interpolation map involving varieties of meteorological elements in neady 50 years was generated based on the Kriging interpolation, and the spatial distribution characteristics of those meteorological ele- ments were analyzed. [ Result] Temperature of Sanjiang Plain decreased with the increase of latitude and altitude, and the annual average temper- atura varied from 2.5 to 4.5 ~(3 generally, showing a zonal distribution. Precipitation of Sanjiang Plain changed spatially and the annual average pre- cipitation varied from 500 to 600 mm symmetrically in northwest-southeast direction. Spatial distribution of the annual average wind speed in San- jiang Plain was identical with the spatial pattern of topography here, and the annual average wind speed changed from 3.0 to 3.6 rn/s in most re- gions. Relative air humidity of Sanjiang Plain in summer half year was relatively high and always above 65%. The maximum sunshine hours of San- jiang Plain in one year distributed similarly to the annual changing curve of solar declination, and both of them presented a normal distribution and changed with geographic latitude. The days from the beginning to the end of daily average temperature ~〉 10 ~C in Sanjiang Plain were 135 -146 d, and its distribution presented a latitudinal trend, with certain vertical zonality. [ Conclusion] The research could provide scientific references for the reasonable arrangement of agricultural production and effective prevention of meteorological disasters in Sanjiang Plain.
基金"The pre-warning and prediction system for unexpected geological calamities in Zhejiangprovince and demonstration of its application - A "provincial key project from the science and technologybureau of Zhejianga key project "the study on forecasting system for heavy rains in Zhejiang province"
文摘1 INTRODUCTION Meteorological factors, especially precipitation, have close links with geological calamities. According to the statistics, more than 70% of the geological calamities in China occur in rainy seasons. Many researchers are thus motivated to study extensively to determine their relationship in the prediction of geological calamltles . They either rely on single measurements of rainfall to seek basis for widespread occurrence of geological calamities or treat antecedent diurnal rainfall with equal importance, though with account of the accumulated effect of preceding rainfall. Furthermore, it is common for quite a number of models to use the rainfall recorded at hydrological or meteorological rain gauges as the one for the interested day, reducing the time validity of the prediction. In our analysis, it is found that the landslides and debris flows in Zhejiang province are related with the antecedent precipitation (but not by a simple accumulation). Critical amounts of accumulated and effective rainfall are used in this work to tell whether there will be geological calamities. Moreover, MM5 is used to forecast rainfall, taking account in equations of the predictand for landslides and debris flows, in attempts to predict the appearance of meteorological condition for geological calamities and improve the rationality of forecasting procedures and time validity of forecasts.
文摘Strategic maintenance plays a key role in ensuring high availability and utilization of the haul trucks,and as equipment began to grow more complex towards the end of the 20th century,there was a need for a proactive maintenance strategy,which led to the development of condition-based maintenance.Realtime condition monitoring(RTCM)is the ability to perform condition monitoring in real-time and has the ability to alert maintenance and operations of abnormal conditions.These alarms can be used as an indication leading to a problem,and if a suitable corrective action is initiated in time,it could result in significant savings of equipment downtime and repair costs.This study aims to compare some maintenance performance indicators prior to and after implementation of RTCM strategy at a mine site using some tests of statistical significance.The study also indicated the presence of seasonality in the data,and thus the data was deseasonalized and detrended prior to being subjected to the statistical tests.Finally,the results indicated that RTCM strategy has proven to be successful in improving the availability for some of the failure categories chosen in this study.
基金This study was supported by National Science Foundation Council of China (No.81700383), Jilin Provincial Industrial Innovation Special Fund Project (No.2016C041), Beijing Natural Science Foundation of China (8152019), Beijing Municipal Science and Technology of Chinese Medicine Development Funds Youth Research Project (No. QN2016-20), and Basic-Clinical Scientific Research Cooperation of Capital Medical University fund (No.17JL72). The authors declare no conflict of interest.
文摘Objective To investigate the impact of meteorological conditions and PM2.5 on the onset of acute aortic dissection in monsoonal climate. Methods A linear regression analysis was performed in monsoonal climate epidemiological survey for a period of four years on the impact of meteorological factors (minimal temperature, mean temperature, maximal temperature, average daily surface temperature, day temperature range, relative humidity, mean wind speed, and atmospheric pressure) and PM2.5 concentration on the daily incidences of acute aortic dissections. Meteorological variables and PM2.5 concentration were retrieved on a daily basis from Beijing Regional Climate Center and the Ministry of Environmental Protection of the People’s Republic of China’s website, and the daily incidences of acute aortic dissections were retrieved from the Clinical Data Analysis and Reporting System in the Emergency and Critical Care Center of Beijing Anzhen Hospital. Results During the study period (from January 2011 to December 2014), 1164 patients were identified as having acute aortic dissections. The corresponding incidences in spring and autumn were 0.96 and 1.00, respectively, which significantly higher than that in summer and winter. The incidences of acute aortic dissection in a day could be predicted by diurnal temperature range (DTR) using the following linear multiple regression models: incidences of acute aortic dissection = 0.543 + 0.025 × DTR. Conclusion This is the first study to show an attributable effect of DTR on acute aortic events in monsoonal climate. Our study confirms that meteorological variables were important factors influencing the incidence of acute aortic dissection.
基金Project on Meteorological Conditions for Selection of Site of Maritime Sporting Base for 26th Summer Universiade 2011
文摘Based on the real-time wind direction and speed data from an automatic meteorological monitoring network in Shenzhen, the wind characteristics of Jue Diao Sha maritime area are analyzed. As indicated in the results, the wind speed of this area is higher than that over the land, the average wind speed is above 3 m/s and the probability for the maximum wind speed to drop below 20 m/s is above 90%. Moreover, the probability for the hourly swing angle of wind direction to become less than 50o is above 80%, suggesting that the wind conditions in the Jue Diao Sha area could meet the requirements of the sporting events. According to the numerical simulation, this area is the best selected site among three candidates. Furthermore, the characteristics of daily land and sea breezes are such that it is suggested the game will be best carried out from 1000 to 1700 Beijing Standard Time.
文摘To reveal the multivariate relationships between man-made and meteorological factors on dust storm frequency, the LUCC data, NDVI remote sensing data and meteorological data for the period of 1983-2013 were combined with dust storm frequency data, and the possible impacts of meteorological and anthropogenic factors on dust storm frequency were analyzed by using regression analysis and PCA (Principal Component Analysis). Results show that the inter-annual dust storm frequency increased gradually. In particular, an increasing trend in recent years, after 2009, is conspicuous. The monthly frequency of dust storms shows higher values between the months of February and May, with the highest mean number of events occurring in April, which accounts for 29% of the annual dust storm frequency. The annual dust storm frequency is positively correlated with wind speed and negatively correlated with precipitation;the monthly dust storm frequency is positively correlated with wind speed, but no significant correlation can be found with precipitation. The relationship between temperature and dust storms is not simply linear, however, a certain correlation with an unremarkable statistical significance can be found between them. Human activities also affect the dynamics of dust storms indirectly via changing vegetation coverage and direct dust emissions. The multivariate analysis further confirmed the association between dust storm frequency and meteorological factors and NDVI. The high loadings of dust storm frequency, wind speed, precipitation and NDVI on a PC indicate that the increased precipitation and NDVI will decrease dust storm frequency, and increased wind speed will increase dust storm frequency.