Volume 33,Issue 3,2005 Table of Contents
2005, 33(3):193-198.
Abstract:
The advancement in the researches on the influence of volcanic eruptions on climate and the main conclusions and progress obtained from statistical analysis and numerical simulation is summarized. Present studies show that major eruptions can produce a decrease in surface air temperature. Due to the seasonal difference of volcanic activities, latitude and intensities, the spatial distribution and the effect on radiation vary. Consequently, the time and augmentation of temperature decrease are not consistent. The volcanic eruptions at the high latitudes mainly influence the same hemisphere, and those at low and middle latitudes influence the both hemispheres. The impact of volcanic eruptions is more obvious at the low latitudes than at the high latitudes, and more obvious in summer than in winter. The influence of volcanic eruptions on precipitation is relatively complex, and there is no consistent conclusion due to the weak volcanic signals in the precipitation series and the influence of other factors such as ENSO.
The advancement in the researches on the influence of volcanic eruptions on climate and the main conclusions and progress obtained from statistical analysis and numerical simulation is summarized. Present studies show that major eruptions can produce a decrease in surface air temperature. Due to the seasonal difference of volcanic activities, latitude and intensities, the spatial distribution and the effect on radiation vary. Consequently, the time and augmentation of temperature decrease are not consistent. The volcanic eruptions at the high latitudes mainly influence the same hemisphere, and those at low and middle latitudes influence the both hemispheres. The impact of volcanic eruptions is more obvious at the low latitudes than at the high latitudes, and more obvious in summer than in winter. The influence of volcanic eruptions on precipitation is relatively complex, and there is no consistent conclusion due to the weak volcanic signals in the precipitation series and the influence of other factors such as ENSO.
2005, 33(3):199-203.
Abstract:
For facilitating the researches in quality control (QC) of surface meteorological data in China, the QC methods of several representative data sets (e.g. GHCN, GDCN and ISH) are introduced. The latest international development and trends of the correlative technologies are expounded. It is indicated that the conventional QC methods are still the basic tools. Along with the development of computer technology, several new technologies, such as auto-control, HCI (Human Computer Interaction), the spatial test method and the technology of combining climate data and statistical test, etc., will be applied to the QC of surface meteorological data to help design the operation flow of quality control of surface meteorological data from autonomous weather stations.
For facilitating the researches in quality control (QC) of surface meteorological data in China, the QC methods of several representative data sets (e.g. GHCN, GDCN and ISH) are introduced. The latest international development and trends of the correlative technologies are expounded. It is indicated that the conventional QC methods are still the basic tools. Along with the development of computer technology, several new technologies, such as auto-control, HCI (Human Computer Interaction), the spatial test method and the technology of combining climate data and statistical test, etc., will be applied to the QC of surface meteorological data to help design the operation flow of quality control of surface meteorological data from autonomous weather stations.
2005, 33(3):204-208.
Abstract:
By means of the sliding-window Chebyshev expansion technique, the objective forecast model (OFM) of heavy rainfall from May to June in the Jianyan station was developed in order to improve the capability of single-station rainfall forecasting. The results show that the objective forecast factors have clear meteorological meaning though simple and the advantages of high prediction accuracy and good stability; the characteristics of the weather patterns at three levels for various models exhibit the reasonable vertical collocations favorable to rainfall process development. The trial use in 2000 and 2002 indicates that the average accuracy of rainfall prediction of OFM is about 50% higher than that of the subjective, and there is no failure in 3 years, especially no miss and failure in 2003. It is indicated that the model is efficient and applicable for the improvement of single station rainfall prediction.
By means of the sliding-window Chebyshev expansion technique, the objective forecast model (OFM) of heavy rainfall from May to June in the Jianyan station was developed in order to improve the capability of single-station rainfall forecasting. The results show that the objective forecast factors have clear meteorological meaning though simple and the advantages of high prediction accuracy and good stability; the characteristics of the weather patterns at three levels for various models exhibit the reasonable vertical collocations favorable to rainfall process development. The trial use in 2000 and 2002 indicates that the average accuracy of rainfall prediction of OFM is about 50% higher than that of the subjective, and there is no failure in 3 years, especially no miss and failure in 2003. It is indicated that the model is efficient and applicable for the improvement of single station rainfall prediction.
2005, 33(3):209.
Abstract:
Tropical cyclones 7514 (Elsle), 7908 (Hope), and 0313 (Dujuan) were compared and analyzed with radar, long-wave radiation (OLR), ambient field, specific humidity field data, etc. The results show that the three typhoons with double eye walls have characteristics of regular and tight spiral cloud bands, strong Subtropical High and weak southwesterly at 850 hPa before landing, which resulted in the strong wind and less rainfall with an extensive influencing area. The long-wave radiation and the rain field have close relationship. All the low OLR centers of three typhoons didn't land, resulting in less rainfall on land. The low OLR centers of three typhoons corresponded to strong rain centers basically. The bigger the gradient of the specific humidity field is, the slower the typhoons moves, and the longer and stronger the rainfall.
Tropical cyclones 7514 (Elsle), 7908 (Hope), and 0313 (Dujuan) were compared and analyzed with radar, long-wave radiation (OLR), ambient field, specific humidity field data, etc. The results show that the three typhoons with double eye walls have characteristics of regular and tight spiral cloud bands, strong Subtropical High and weak southwesterly at 850 hPa before landing, which resulted in the strong wind and less rainfall with an extensive influencing area. The long-wave radiation and the rain field have close relationship. All the low OLR centers of three typhoons didn't land, resulting in less rainfall on land. The low OLR centers of three typhoons corresponded to strong rain centers basically. The bigger the gradient of the specific humidity field is, the slower the typhoons moves, and the longer and stronger the rainfall.
2005, 33(3):214-217.
Abstract:
A diagnostic analysis was made of a local lasting heavy rainstorm took place in the central part of Shaanxi Province on 28 June 1994. The heavy rainstorm appeared in the front of a 500 hPa trough near the shear line of a depression on the 700 hPa, happened in the superposed zone between the right divergence area around the entrance of the upper-troposphere jet and the left convergence area of the lower-troposphere jet, and was related with the mesoscale cyclone on the surface. The diagnostic results show that the mesoscale cyclone on the surface was caused by the sub-circulation resulted from the coupling of upper and lower jets and the sub-circulation controlled the development and change of mesoscale systems.
A diagnostic analysis was made of a local lasting heavy rainstorm took place in the central part of Shaanxi Province on 28 June 1994. The heavy rainstorm appeared in the front of a 500 hPa trough near the shear line of a depression on the 700 hPa, happened in the superposed zone between the right divergence area around the entrance of the upper-troposphere jet and the left convergence area of the lower-troposphere jet, and was related with the mesoscale cyclone on the surface. The diagnostic results show that the mesoscale cyclone on the surface was caused by the sub-circulation resulted from the coupling of upper and lower jets and the sub-circulation controlled the development and change of mesoscale systems.
2005, 33(3):218-221226.
Abstract:
The time-frequency structure of sea surface temperature anomaly (SSTA) in the Nino regions was studied with wavelet transform techniques using SST data from 1950 to 2003 over the Nino regions. The results show that there were multi-scaled structures nested one another in SSTA with varied scales of 2-7, 8-20 and over 30 years. The power of the warm/cold events was concentrated on the 2-7 year scales with the quasi-four year fluctuation being the most remarkable. The power and frequency structure of the same event are different in different Nino regions. The intensity of oscillations is increasing at all scales after 1970 and shows a tendency towards low frequencies.
The time-frequency structure of sea surface temperature anomaly (SSTA) in the Nino regions was studied with wavelet transform techniques using SST data from 1950 to 2003 over the Nino regions. The results show that there were multi-scaled structures nested one another in SSTA with varied scales of 2-7, 8-20 and over 30 years. The power of the warm/cold events was concentrated on the 2-7 year scales with the quasi-four year fluctuation being the most remarkable. The power and frequency structure of the same event are different in different Nino regions. The intensity of oscillations is increasing at all scales after 1970 and shows a tendency towards low frequencies.
2005, 33(3):222.
Abstract:
An analysis was made of the Doppler radar products and the thunder-lighting parameters of a severe convective weather event occurred on 12 April 2003 over the central and the northern Jiangxi Province. Results show that the thunder-lightning parameters are more sensitive to the strong convection weather. The movement of the thunder-lightning zone corresponds with the moving track of the strong convective cell. The thunder-lightning frequency change indicates the different development phases of the severe convective weather event. The type of convection can be identified through thunder-lightning polarity change. Therefore, the thunder-lightning parameters can be used in weather forecasting in combination with radar echo data and satellite cloud pictures.
An analysis was made of the Doppler radar products and the thunder-lighting parameters of a severe convective weather event occurred on 12 April 2003 over the central and the northern Jiangxi Province. Results show that the thunder-lightning parameters are more sensitive to the strong convection weather. The movement of the thunder-lightning zone corresponds with the moving track of the strong convective cell. The thunder-lightning frequency change indicates the different development phases of the severe convective weather event. The type of convection can be identified through thunder-lightning polarity change. Therefore, the thunder-lightning parameters can be used in weather forecasting in combination with radar echo data and satellite cloud pictures.
2005, 33(3):227-230.
Abstract:
A standardization is conducted on the annual minimum air temperature data from all the counties of Fujian Province in the 50 years from 1950/1951 to 1999/2000, and an analysis are made of the characteristics of the colder-than-normal years. The results show that in the 50 years, the lowest year of annual air temperature is 1954/1955, and the third lowest year is in 1999/2000; the abnormal air temperature may occur while monthly mean temperature is normal in winter; some stations are still normal when the whole province is identified as in a colder-than-normal year, with the difference up to four grades; if the annual minimum air temperature assessment of the whole province shows abnormalhy cold or the colder-than-normal, there will probably occur cold damage or chilling injury of orchards, flowers, and crops.
A standardization is conducted on the annual minimum air temperature data from all the counties of Fujian Province in the 50 years from 1950/1951 to 1999/2000, and an analysis are made of the characteristics of the colder-than-normal years. The results show that in the 50 years, the lowest year of annual air temperature is 1954/1955, and the third lowest year is in 1999/2000; the abnormal air temperature may occur while monthly mean temperature is normal in winter; some stations are still normal when the whole province is identified as in a colder-than-normal year, with the difference up to four grades; if the annual minimum air temperature assessment of the whole province shows abnormalhy cold or the colder-than-normal, there will probably occur cold damage or chilling injury of orchards, flowers, and crops.
2005, 33(3):231-234.
Abstract:
The correction and interpolation were conducted on the radiation observation in Mojiaquanwan and Yushu around Xining, and the spatial distribution and inter-annual variation of solar radiation were analyzed systematically. The results stows that the global radiation is relatively high over the Qinghai Plateau and the distribution shows a tendency of higher in the West is and lower in the East; the global radiation value was higher in the 1970's and obvious low in the 1980's, increased again from the end of the 1980's to the beginning of 1990's, but decreased after the middle 1990's. The high and low periods in the 1970s and 1980s are closely related to the cloud amount and precipitation over Qinghai Province and volcanic eruptions across the world during the same periods. Volcanic eruption was an important cause of the decrease in solar radiation.
The correction and interpolation were conducted on the radiation observation in Mojiaquanwan and Yushu around Xining, and the spatial distribution and inter-annual variation of solar radiation were analyzed systematically. The results stows that the global radiation is relatively high over the Qinghai Plateau and the distribution shows a tendency of higher in the West is and lower in the East; the global radiation value was higher in the 1970's and obvious low in the 1980's, increased again from the end of the 1980's to the beginning of 1990's, but decreased after the middle 1990's. The high and low periods in the 1970s and 1980s are closely related to the cloud amount and precipitation over Qinghai Province and volcanic eruptions across the world during the same periods. Volcanic eruption was an important cause of the decrease in solar radiation.
2005, 33(3):235-239.
Abstract:
Based on the observational data from conventional and automatic weather stations and numerical forecast products of the mesoscale model MM5, the synoptic system and wind field structure of a storm surge in the Bohai Sea on 11 October 2003 were analyzed. The results show that the main causes of the storm surge are the strong northeast wind engendered by strong cold air from northeast and warm air from southwest and inversion; the inshore transport of seawater lasted 10-12 hours over an area of 100 km, directly resulted from the inshore wind and astronomical tides concurrently. It is also found that the occurrence frequency of storm surges has increased obviously since 1985.
Based on the observational data from conventional and automatic weather stations and numerical forecast products of the mesoscale model MM5, the synoptic system and wind field structure of a storm surge in the Bohai Sea on 11 October 2003 were analyzed. The results show that the main causes of the storm surge are the strong northeast wind engendered by strong cold air from northeast and warm air from southwest and inversion; the inshore transport of seawater lasted 10-12 hours over an area of 100 km, directly resulted from the inshore wind and astronomical tides concurrently. It is also found that the occurrence frequency of storm surges has increased obviously since 1985.
2005, 33(3):240-244.
Abstract:
對2003年7月8～9日發生在湖北中部并且造成泥石流災害的大暴雨過程進行了中尺度分析，結果表明：①在有利的大尺度系統下產生的中小尺度系統是暴雨產生的最直接的系統；②湖北省泥石流災害發生在特殊的地理位置，秭歸、宜昌、宜都等鄂西山地到江漢平原的過渡帶是泥石流災害的多發地；③暴雨尤其是泥石流發生地周圍的歷時短、局地性強的大暴雨是泥石流災害直接的誘發原因；④中尺度系統的源地與地形有關，在西南氣流的背風坡容易形成中尺度系統；⑤多普勒雷達是監測中尺度系統的強有力工具，一個中α尺度云團中可以是一個也可以有兩個以上的混合回波團或帶；⑥中尺度渦旋形成于低空急流左側強正渦度中心附近。
對2003年7月8～9日發生在湖北中部并且造成泥石流災害的大暴雨過程進行了中尺度分析，結果表明：①在有利的大尺度系統下產生的中小尺度系統是暴雨產生的最直接的系統；②湖北省泥石流災害發生在特殊的地理位置，秭歸、宜昌、宜都等鄂西山地到江漢平原的過渡帶是泥石流災害的多發地；③暴雨尤其是泥石流發生地周圍的歷時短、局地性強的大暴雨是泥石流災害直接的誘發原因；④中尺度系統的源地與地形有關，在西南氣流的背風坡容易形成中尺度系統；⑤多普勒雷達是監測中尺度系統的強有力工具，一個中α尺度云團中可以是一個也可以有兩個以上的混合回波團或帶；⑥中尺度渦旋形成于低空急流左側強正渦度中心附近。
2005, 33(3):245-249.
Abstract:
利用多普勒雷達等多種觀測資料，分析2003年6月22日發生在湖北省安陸北部的山洪，并初步概括了引發山洪暴雨的概念模型，結果表明：①引發安陸山洪的暴雨強度大、持續時間短，強降雨帶(團)具有明顯的中β尺度特征，山洪爆發地區的強降水由中β尺度降水帶上與深厚對流云活動有關的中γ尺度強降水雨團造成；②引發山洪暴雨的概念模型可以描述如下：在有利的大尺度環流背景及高低空急流耦合下，天氣尺度系統影響產生大范圍降水，當受外界強迫或者存在大氣對流不穩定度增強和對流觸發機制時，大范圍降雨帶上產生中β或中γ尺度強對流雨團導致大暴雨甚至特大暴雨天氣，在有利的地形條件下爆發山洪，特別是在山區前期發生了降水，土壤濕度大，地表滲透系數小的情況下極易發生。
利用多普勒雷達等多種觀測資料，分析2003年6月22日發生在湖北省安陸北部的山洪，并初步概括了引發山洪暴雨的概念模型，結果表明：①引發安陸山洪的暴雨強度大、持續時間短，強降雨帶(團)具有明顯的中β尺度特征，山洪爆發地區的強降水由中β尺度降水帶上與深厚對流云活動有關的中γ尺度強降水雨團造成；②引發山洪暴雨的概念模型可以描述如下：在有利的大尺度環流背景及高低空急流耦合下，天氣尺度系統影響產生大范圍降水，當受外界強迫或者存在大氣對流不穩定度增強和對流觸發機制時，大范圍降雨帶上產生中β或中γ尺度強對流雨團導致大暴雨甚至特大暴雨天氣，在有利的地形條件下爆發山洪，特別是在山區前期發生了降水，土壤濕度大，地表滲透系數小的情況下極易發生。
2005, 33(3):250-255.
Abstract:
1999年12月下旬特大霜凍災害是云南1951年以來損失最大的一次自然災害，受災面積85萬hm^2，直接經濟損失55億元。利用高空和地面氣象資料，分析了嚴重低溫霜凍災害的天氣成因，并與歷史上的1973／1974、1975／1976年冬季云南兩次嚴重霜凍災害進行了比較。結果表明：特大霜凍災害是在云南連續暖冬背景下發生的，對云南經濟作物和熱帶作物的危害最大。高空冷平流與地面冷高壓控制下長時間夜間晴空輻射冷卻降溫是此次重霜凍形成的主要原因，500hPa、700hPa偏北氣流和干冷南支槽是主要影響天氣系統。碧空無云、靜風、濕度小、氣溫低、氣壓高、露點溫度特低是此次重霜凍的主要氣象要素變化特征。凍害以滇南熱帶作物種植區最為嚴重。關鍵詞霜凍低溫冷平流晴空輻射暖冬
1999年12月下旬特大霜凍災害是云南1951年以來損失最大的一次自然災害，受災面積85萬hm^2，直接經濟損失55億元。利用高空和地面氣象資料，分析了嚴重低溫霜凍災害的天氣成因，并與歷史上的1973／1974、1975／1976年冬季云南兩次嚴重霜凍災害進行了比較。結果表明：特大霜凍災害是在云南連續暖冬背景下發生的，對云南經濟作物和熱帶作物的危害最大。高空冷平流與地面冷高壓控制下長時間夜間晴空輻射冷卻降溫是此次重霜凍形成的主要原因，500hPa、700hPa偏北氣流和干冷南支槽是主要影響天氣系統。碧空無云、靜風、濕度小、氣溫低、氣壓高、露點溫度特低是此次重霜凍的主要氣象要素變化特征。凍害以滇南熱帶作物種植區最為嚴重。關鍵詞霜凍低溫冷平流晴空輻射暖冬
2005, 33(3):256-259.
Abstract:
Based on the PMS data obtained during a returning process, the inhomogeneity of stratiform clouds in returning processes was analyzed from the aspect of microphysical structure. It is found that when the aircraft flies into stronger precipitating cloud bands, the main cloud physical parameters (liquid water content, particle mean diameter and concentration, and temperature) change greatly; the liquid water content, the mean diameter and the particle concentration leap up; spectrum width becomes wider; temperature drops; and so on. In the stronger cloud band, temperature variation is smaller and meanwhile temperature is lower. The stronger precipitating cloud bands have abundant ice crystals, indicating better natural seeding potential.
Based on the PMS data obtained during a returning process, the inhomogeneity of stratiform clouds in returning processes was analyzed from the aspect of microphysical structure. It is found that when the aircraft flies into stronger precipitating cloud bands, the main cloud physical parameters (liquid water content, particle mean diameter and concentration, and temperature) change greatly; the liquid water content, the mean diameter and the particle concentration leap up; spectrum width becomes wider; temperature drops; and so on. In the stronger cloud band, temperature variation is smaller and meanwhile temperature is lower. The stronger precipitating cloud bands have abundant ice crystals, indicating better natural seeding potential.
2005, 33(3):260-263.
Abstract:
The air-to-ground data transmission system developed jointly by the Shaanxi Weather Modification Center and the Xi'an Jingbo Company is described. This system was used in 25 operation flights of rain enhancement in 2002 and 2003, which adopts the transmission mode with wire and wireless combined and can avoid unstable signals in short-wave communication and transmit sound and data normally. With this system, the commanding staff on the ground can learn about the status of the seeding airplane promptly. The real time data of temperature, humidity, flight altitude and flight track from the seeding airplane were compared with the data received on the ground by the Xi'an Weather Modification Center on 19 September 2003. The comparison suggests that the data received in airplane is well in agreement with the transmitted data from the airplane at the same time, and that the system performed well and steadily.
The air-to-ground data transmission system developed jointly by the Shaanxi Weather Modification Center and the Xi'an Jingbo Company is described. This system was used in 25 operation flights of rain enhancement in 2002 and 2003, which adopts the transmission mode with wire and wireless combined and can avoid unstable signals in short-wave communication and transmit sound and data normally. With this system, the commanding staff on the ground can learn about the status of the seeding airplane promptly. The real time data of temperature, humidity, flight altitude and flight track from the seeding airplane were compared with the data received on the ground by the Xi'an Weather Modification Center on 19 September 2003. The comparison suggests that the data received in airplane is well in agreement with the transmitted data from the airplane at the same time, and that the system performed well and steadily.
2005, 33(3):264-267.
Abstract:
The operating and commanding system of cloud seeding operation is a very important condition for rocket and artillery rain enhancement and hail suppression to gain satisfactory results. The new generation cloud-seeding operation commanding system developed by using C ++ and Visual Studio.net and digital radar includes six sub-systems: weather radar monitoring, atmosphere detection, rocket and artillery seeding operation and decision-making, operating information communication, operating effectiveness evaluation, operation archives and data management. The application indicates that the system has advanced functions and a friendly interface and is easy and rapid to handle and use. Considering its very high operating and commanding capability and technological level, it is an ideal operating platform of cloud seeding operation for municipal weather modification office.
The operating and commanding system of cloud seeding operation is a very important condition for rocket and artillery rain enhancement and hail suppression to gain satisfactory results. The new generation cloud-seeding operation commanding system developed by using C ++ and Visual Studio.net and digital radar includes six sub-systems: weather radar monitoring, atmosphere detection, rocket and artillery seeding operation and decision-making, operating information communication, operating effectiveness evaluation, operation archives and data management. The application indicates that the system has advanced functions and a friendly interface and is easy and rapid to handle and use. Considering its very high operating and commanding capability and technological level, it is an ideal operating platform of cloud seeding operation for municipal weather modification office.
2005, 33(3):268-270.
Abstract:
In order to solve the problem of batch testing and calibrating of sensors, the CAWS-JC01 integrated sensor testing system was developed. The system can improve greatly the capability of the sensor testing equipment in automatic operation, batch testing and data processing. The main components, structure and technical specifications of the CAWS-JC01 integrated sensor testing system are introduced. The system is applicable to the batch testing of various kinds of sensors and is the dedicated testing equipment of various sensors of automatic weather stations for the province/prefecture-level meteorological metrological departments.
In order to solve the problem of batch testing and calibrating of sensors, the CAWS-JC01 integrated sensor testing system was developed. The system can improve greatly the capability of the sensor testing equipment in automatic operation, batch testing and data processing. The main components, structure and technical specifications of the CAWS-JC01 integrated sensor testing system are introduced. The system is applicable to the batch testing of various kinds of sensors and is the dedicated testing equipment of various sensors of automatic weather stations for the province/prefecture-level meteorological metrological departments.
2005, 33(3):271-274.
Abstract:
The use of the ground-based GPS observation technology for estimating precipitable water vapor (PWV) is a brand-new technique developed in the 1990s. An efficient data communication network can help download data in real time and control the GPS receiver remotely and provide the essential technical support for the operational use of ground-based GPS data. The GPS communication and remote control system was developed by using a modem and the public switch telephone network (PSTN). Adopting the dialing approach, the system configures the GPS receiver specified by the GPS water vapor remote sensing network and downloads the data stored in the receiver. The application of this communication system can enhance the maintainability of the system and facilitate the operational application of the GPS water vapor remote sensing network. However, there are still some problems in the system needed to be solved such as low speed and manual control.
The use of the ground-based GPS observation technology for estimating precipitable water vapor (PWV) is a brand-new technique developed in the 1990s. An efficient data communication network can help download data in real time and control the GPS receiver remotely and provide the essential technical support for the operational use of ground-based GPS data. The GPS communication and remote control system was developed by using a modem and the public switch telephone network (PSTN). Adopting the dialing approach, the system configures the GPS receiver specified by the GPS water vapor remote sensing network and downloads the data stored in the receiver. The application of this communication system can enhance the maintainability of the system and facilitate the operational application of the GPS water vapor remote sensing network. However, there are still some problems in the system needed to be solved such as low speed and manual control.
2005, 33(3):275-277.
Abstract:
衛星通信小型地球站(VSAT小站)這一現代通信系統正越來越多地在國內外得到廣泛應用。由于VSAT小站的部件主要由大規模集成電路構成并且設備安裝時常常將天線置于樓頂，因此，在日常工作中因遭受雷電襲擊而造成設備損壞的事件常常發生。本文主要依據《建筑物防雷設計規范》、《微波站防雷與接地設計規范》和IEC有關標準，結合目前國內氣象、海關、煙草、金融等行業大量使用的VSAT通信小站結構原理和現代雷電防護理論，就如何對其進行雷擊電磁脈沖的綜合防護進行了探討。強調了在現代防雷接地系統中，重要的是等電位系統的結構而不是接地電阻阻值的大小。
衛星通信小型地球站(VSAT小站)這一現代通信系統正越來越多地在國內外得到廣泛應用。由于VSAT小站的部件主要由大規模集成電路構成并且設備安裝時常常將天線置于樓頂，因此，在日常工作中因遭受雷電襲擊而造成設備損壞的事件常常發生。本文主要依據《建筑物防雷設計規范》、《微波站防雷與接地設計規范》和IEC有關標準，結合目前國內氣象、海關、煙草、金融等行業大量使用的VSAT通信小站結構原理和現代雷電防護理論，就如何對其進行雷擊電磁脈沖的綜合防護進行了探討。強調了在現代防雷接地系統中，重要的是等電位系統的結構而不是接地電阻阻值的大小。
2005, 33(3):278-282288.
Abstract:
As the standards of NASA and EOS data storage and distribution, HDF-EOS specialized in dealing with diversified EOS products. EOS data are used widely in meteorological fields, so it is the key to master the HDF-EOS data format and data import to the further development and application of EOS data. The structure of image module, scientific data, and Vdata module (tabular data) in HDF data files and the data format of dot, strip, and grid data and metadata in HDF-EOS files, as well as the relative software to open HDF format data to import and browse HDF-EOS data, are introduced.
As the standards of NASA and EOS data storage and distribution, HDF-EOS specialized in dealing with diversified EOS products. EOS data are used widely in meteorological fields, so it is the key to master the HDF-EOS data format and data import to the further development and application of EOS data. The structure of image module, scientific data, and Vdata module (tabular data) in HDF data files and the data format of dot, strip, and grid data and metadata in HDF-EOS files, as well as the relative software to open HDF format data to import and browse HDF-EOS data, are introduced.
2005, 33(3):283-288.
Abstract:
An operational platform of refined temperature forecasting was developed based on a meso-scale numerical weather forecast model for Ningxia Province. It can produce, modify and display the hour-to-hour air temperature forecasts for all the stations of Ningxia Province in graphic mode. By means of the regression model of the central meteorological station and the other stations in the same area, the temperature forecast adjustment for all the stations in Ningxia Province can be conducted easily by adjusting temporal curves under the condition of the physical processes relative to temperature forecasting keeping unchanged. It provides a sound support to the system of refined weather forecasting.
An operational platform of refined temperature forecasting was developed based on a meso-scale numerical weather forecast model for Ningxia Province. It can produce, modify and display the hour-to-hour air temperature forecasts for all the stations of Ningxia Province in graphic mode. By means of the regression model of the central meteorological station and the other stations in the same area, the temperature forecast adjustment for all the stations in Ningxia Province can be conducted easily by adjusting temporal curves under the condition of the physical processes relative to temperature forecasting keeping unchanged. It provides a sound support to the system of refined weather forecasting.
External LinksChina Meteorological AdministrationCMA Meteorological Observation CentreChinese Academy of Meteorological SciencesBeijing Meteorological ServiceNational Satellite Meteorological Center
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Supported by:Beijing E-Tiller Technology Development Co., Ltd.
Supported by:Beijing E-Tiller Technology Development Co., Ltd.