Volume 33,Issue 4,2005 Table of Contents
1 Review of Researches on Remote Sensing Monitoring and Impact on Environment of Land Use/Cover Change
2005, 33(4):289-294.
Abstract:
Land Use/Cover Change (LUCC) is one of important focuses in global change research and has great influence on the global ecological environment. Some LUCC remote sensing application techniques, such as remote sensing data sources, remote sensing classification and dynamic change monitoring methods, are introduced. The current progress of LUCC's impact on climate and hydrology is reviewed; especially, the application of numerical simulation methods to LUCC research is described. The existing problems and the development trends of LUCC research are discussed in the aspects of dynamic mechanisms, impacts on the environment, remote sensing technology, the composite application of multi-source data, and numerical experiment, etc.
Land Use/Cover Change (LUCC) is one of important focuses in global change research and has great influence on the global ecological environment. Some LUCC remote sensing application techniques, such as remote sensing data sources, remote sensing classification and dynamic change monitoring methods, are introduced. The current progress of LUCC's impact on climate and hydrology is reviewed; especially, the application of numerical simulation methods to LUCC research is described. The existing problems and the development trends of LUCC research are discussed in the aspects of dynamic mechanisms, impacts on the environment, remote sensing technology, the composite application of multi-source data, and numerical experiment, etc.
2005, 33(4):295-299.
Abstract:
An analysis was made of the development trend of meteorological satellite data transmission technology. The data transmission frequency of meteorological satellite is changing from L-band only to L-band and X-band plus K-band, adopting higher frequency and CCSDS package transmission. The convolutional multilevel R-S coding technology with advanced error correcting and antijamming capabilities is adopted, changing analog data into digital data. The data transmission characteristics of polar orbiting and goestationary meteorological satellites across the world are summarized to help data-receiving stations to make preparatory for receiving the new meteorological satellite data.
An analysis was made of the development trend of meteorological satellite data transmission technology. The data transmission frequency of meteorological satellite is changing from L-band only to L-band and X-band plus K-band, adopting higher frequency and CCSDS package transmission. The convolutional multilevel R-S coding technology with advanced error correcting and antijamming capabilities is adopted, changing analog data into digital data. The data transmission characteristics of polar orbiting and goestationary meteorological satellites across the world are summarized to help data-receiving stations to make preparatory for receiving the new meteorological satellite data.
2005, 33(4):300-304.
Abstract:
The numerical forecast products had been applied in many stations, but the analysis and application of the rich numerical forecast products were not enough. Using the physical forecast products of T106 and the conventional meteorological data, the spring heavy rainfall events in Hubei Province from 1998 to 2001 were diagnosed and analyzed, focused on the physical factor diagnoses. The results revealed the characteristics of some physical factors and their structure, including the shape, forecast value, hierarchical configuration of various physical factors, which help understand the formation mechanisms of heavy rainfall, work out forecasting indices and the model of spring heavy rainfall location forecasting in Hubei Province, and provide references for finer heavy rain forecasting in the future.
The numerical forecast products had been applied in many stations, but the analysis and application of the rich numerical forecast products were not enough. Using the physical forecast products of T106 and the conventional meteorological data, the spring heavy rainfall events in Hubei Province from 1998 to 2001 were diagnosed and analyzed, focused on the physical factor diagnoses. The results revealed the characteristics of some physical factors and their structure, including the shape, forecast value, hierarchical configuration of various physical factors, which help understand the formation mechanisms of heavy rainfall, work out forecasting indices and the model of spring heavy rainfall location forecasting in Hubei Province, and provide references for finer heavy rain forecasting in the future.
2005, 33(4):305-310.
Abstract:
通过普查、分析黄河花园口站洪峰流量大于等于4000m^3／s的黄河中游8次洪水过程，着重分析了洪水过程中小花间区域致洪暴雨发生前的天气学特征，归纳出造成小花间洪水过程的天气形势主要有鞍型场和台风倒槽两大类型，并建立了相应的500、700hPa高度场模型和热力、水汽条件诊断模型及动力条件物理量诊断模型，并采用相似离度进行人型判别。该预报模型在2003年预报业务试验中，对黄河秋汛期间发生在小花间区域的致洪暴雨过程进行了较为成功的预报。
通过普查、分析黄河花园口站洪峰流量大于等于4000m^3／s的黄河中游8次洪水过程，着重分析了洪水过程中小花间区域致洪暴雨发生前的天气学特征，归纳出造成小花间洪水过程的天气形势主要有鞍型场和台风倒槽两大类型，并建立了相应的500、700hPa高度场模型和热力、水汽条件诊断模型及动力条件物理量诊断模型，并采用相似离度进行人型判别。该预报模型在2003年预报业务试验中，对黄河秋汛期间发生在小花间区域的致洪暴雨过程进行了较为成功的预报。
2005, 33(4):311-313.
Abstract:
By analyzing 194 landslide cases from 1975 to 2002 in Hubei Province,it is found that landslides in Hubei mainly occurred from May to August, which is similar to the monthly mean rainfall distribution;the main landslide area is the mountainous region in the western Hubei; and the high-frequency center is in the Three Gorges Reservoir area;landslides have a close relation with the antecedent rainfall amount, especially heavy rainfall, which accounts for 63.1% of the total amount. The critical rainfall amount was determined and the potential forecasting model of heavy rainfall regime landslides was built with the effective rainfall method.
By analyzing 194 landslide cases from 1975 to 2002 in Hubei Province,it is found that landslides in Hubei mainly occurred from May to August, which is similar to the monthly mean rainfall distribution;the main landslide area is the mountainous region in the western Hubei; and the high-frequency center is in the Three Gorges Reservoir area;landslides have a close relation with the antecedent rainfall amount, especially heavy rainfall, which accounts for 63.1% of the total amount. The critical rainfall amount was determined and the potential forecasting model of heavy rainfall regime landslides was built with the effective rainfall method.
2005, 33(4):318-323.
Abstract:
The correlation between tropic sea surface temperature of global and NAO and ENSO events were studied by means of bivariate wavelet analysis. Results show that the correlation between tropic SST and ENSO cycle on the time scales of 2 to 7 years and over 30 years is apparent with the maximum variance contribution appearing at the period of 4 years. The most striking correlation between North Atlantic SST and ENSO events was found on the time scales of 4 years and 15 years. There is weak anticorrelation between NAO and ENSO events on the time scales of 2 to 7 years and 10 to 24 years, and weak correlation on over 25 year scale.
The correlation between tropic sea surface temperature of global and NAO and ENSO events were studied by means of bivariate wavelet analysis. Results show that the correlation between tropic SST and ENSO cycle on the time scales of 2 to 7 years and over 30 years is apparent with the maximum variance contribution appearing at the period of 4 years. The most striking correlation between North Atlantic SST and ENSO events was found on the time scales of 4 years and 15 years. There is weak anticorrelation between NAO and ENSO events on the time scales of 2 to 7 years and 10 to 24 years, and weak correlation on over 25 year scale.
2005, 33(4):324-329.
Abstract:
An analysis was made of 12 weather processes with rainstorms and 9 processes without rainstorms from 21 June to 11 July 2003. The synoptic patterns and physical quantities for the two kinds of processes were compared. The composite-average physical variables for the two kinds of weather processes were calculated, and the thermal and dynamical conditions were analyzed respectively using T213 grid data at 20:00, in combination with the position of the ridge line of Subtropical High and the position of the surface front. Based on the results, a concept prediction model for the short-range heavy rainfall was designed.
An analysis was made of 12 weather processes with rainstorms and 9 processes without rainstorms from 21 June to 11 July 2003. The synoptic patterns and physical quantities for the two kinds of processes were compared. The composite-average physical variables for the two kinds of weather processes were calculated, and the thermal and dynamical conditions were analyzed respectively using T213 grid data at 20:00, in combination with the position of the ridge line of Subtropical High and the position of the surface front. Based on the results, a concept prediction model for the short-range heavy rainfall was designed.
2005, 33(4):330-333.
Abstract:
A diagnostic analysis was made of the circulation background, dynamical and thermal and water vapor conditions for a heavy rain event on the 1 April 2004 over the eastern Gansu Province, aiming to find out useful forecasting hints for the sort of heavy rainfall. The results show that the main influencing factors include: temperature increased obviously 48 and 24 hours before raining; surface humid-static energy increased rapidly; there existed strong cold air activity, remarkable mid- and lower-level convection, profound positive vorticity, lower-level low-vortex convergence, and upper-level strong divergence at the end.
A diagnostic analysis was made of the circulation background, dynamical and thermal and water vapor conditions for a heavy rain event on the 1 April 2004 over the eastern Gansu Province, aiming to find out useful forecasting hints for the sort of heavy rainfall. The results show that the main influencing factors include: temperature increased obviously 48 and 24 hours before raining; surface humid-static energy increased rapidly; there existed strong cold air activity, remarkable mid- and lower-level convection, profound positive vorticity, lower-level low-vortex convergence, and upper-level strong divergence at the end.
2005, 33(4):334-339.
Abstract:
对三峡水库蓄水前位于坝区长江左、右两岸的3组气温观测资料进行对比分析，结果表明：①水体对水库周边气温有白天降温、夜间增温效应，可抑制极端最高气温，抬升极端最低气温；②总体上增温幅度比降温幅度大，增温幅度夏季大于冬季，春秋季居中，在20：00夏半年多大于冬半年，在08：00冬半年多大于夏半年，20：00、08：00增温幅度0．2～1．0℃的日数分别占总日数的46％、55％以上；③增温效应与降水季节性变化趋势基本一致，降水多的月份增温明显，降水少的月份增温幅度则较小；④降温幅度为春夏季小于秋冬季；⑤逐时气温分析显示，远水区较近水区各时次气温在10：00～15：00高0．1～0．4℃，其它时间尤其是夜间低0．1～0．7℃。
对三峡水库蓄水前位于坝区长江左、右两岸的3组气温观测资料进行对比分析，结果表明：①水体对水库周边气温有白天降温、夜间增温效应，可抑制极端最高气温，抬升极端最低气温；②总体上增温幅度比降温幅度大，增温幅度夏季大于冬季，春秋季居中，在20：00夏半年多大于冬半年，在08：00冬半年多大于夏半年，20：00、08：00增温幅度0．2～1．0℃的日数分别占总日数的46％、55％以上；③增温效应与降水季节性变化趋势基本一致，降水多的月份增温明显，降水少的月份增温幅度则较小；④降温幅度为春夏季小于秋冬季；⑤逐时气温分析显示，远水区较近水区各时次气温在10：00～15：00高0．1～0．4℃，其它时间尤其是夜间低0．1～0．7℃。
2005, 33(4):340-344.
Abstract:
In order to develop and utilize reasonably climate resources and offer a scientific basis for the sub-area management of livestock production over grasslands, an analysis was made of the Inner Mongolia grassland climate characteristics and effects of climate on the growth of pasture grass, the distribution of domestic animal breeds and the soil environment. It is found that some isolines of climatic moisture are almost superposed with the boundaries of soil, which indicates that the formation of soil zones is closely related to climatic conditions, and climate and soil environment are main influence factors for pasture types and the ecosystem. Based on the climatic moisture, in combination with the distribution characteristics of soil over Inner Mongolia, a regionalization was carried out of grassland ecological types, which is not only rational, but also stable. It is pointed out that the climatic warming and the resulting changes in recent years improved, to some extent, the productivity of the grasslands, but not changed the ecotype in Inner Mongolia.
In order to develop and utilize reasonably climate resources and offer a scientific basis for the sub-area management of livestock production over grasslands, an analysis was made of the Inner Mongolia grassland climate characteristics and effects of climate on the growth of pasture grass, the distribution of domestic animal breeds and the soil environment. It is found that some isolines of climatic moisture are almost superposed with the boundaries of soil, which indicates that the formation of soil zones is closely related to climatic conditions, and climate and soil environment are main influence factors for pasture types and the ecosystem. Based on the climatic moisture, in combination with the distribution characteristics of soil over Inner Mongolia, a regionalization was carried out of grassland ecological types, which is not only rational, but also stable. It is pointed out that the climatic warming and the resulting changes in recent years improved, to some extent, the productivity of the grasslands, but not changed the ecotype in Inner Mongolia.
2005, 33(4):345-349354.
Abstract:
The precipitation departure in the growing season (April to September) of crops over Northeast China was analyzed with the rainfall data of 52 stations from 1951 to 2000 over Northeast China. The results show that there was a decreasing trend generally in precipitation with the periods being about 3-7, 12 and 30 years, with drought years more than flooding years in the past 50 years. According to the rainfall anomaly in growing season, Northeast China can be divided into several abnormal areas: a dry trend the middle, southern and eastern parts; and relatively frequent floods/droughts in the western. Considering the decreasing precipitation, it is suggested to adopt dry-farming and water-saving agriculture.
The precipitation departure in the growing season (April to September) of crops over Northeast China was analyzed with the rainfall data of 52 stations from 1951 to 2000 over Northeast China. The results show that there was a decreasing trend generally in precipitation with the periods being about 3-7, 12 and 30 years, with drought years more than flooding years in the past 50 years. According to the rainfall anomaly in growing season, Northeast China can be divided into several abnormal areas: a dry trend the middle, southern and eastern parts; and relatively frequent floods/droughts in the western. Considering the decreasing precipitation, it is suggested to adopt dry-farming and water-saving agriculture.
2005, 33(4):350-354.
Abstract:
Net primary productivity ( N _ pp ) is one of useful indexes in global change studies. Utilization of remote sensing data from meteorological satellites is an objective way to estimate N _ pp . Using the processed annual normalization vegetation index, N _ pp values can be estimated from an experimental model (NPP-RS). The relationship between each crop's N _ pp and yields was then determined. The total yields can be assessed by the N _ pp value. The total yields and the yields of main crops from 1995 to 2000 in Jilin Province were estimated. The mean relative error is 13.6% for total yields, and 17.6% and 6.7% for maize and rice, respectively.
Net primary productivity ( N _ pp ) is one of useful indexes in global change studies. Utilization of remote sensing data from meteorological satellites is an objective way to estimate N _ pp . Using the processed annual normalization vegetation index, N _ pp values can be estimated from an experimental model (NPP-RS). The relationship between each crop's N _ pp and yields was then determined. The total yields can be assessed by the N _ pp value. The total yields and the yields of main crops from 1995 to 2000 in Jilin Province were estimated. The mean relative error is 13.6% for total yields, and 17.6% and 6.7% for maize and rice, respectively.
2005, 33(4):355-359.
Abstract:
According to precipitation data from 1951 to 2002, the precipitation distribution characteristics and variation tendency were analyzed. There was great variation in year-to-year precipitation with the maximum being five times greater than the minimum. The seasonal distributions were quite uneven with a general downward trend; especially since 1997 precipitation has been smaller than the normal. By means of monthly precipitation and temperature data from 1951 to 2002 and an empirical formula of land surface evaporation, the land-surface evaporating, evaporating coefficient and available precipitation coefficient were calculated; it is concluded that water resources and precipitation have similar variation characteristics and there occurred frequently droughts in spring in Taian. Through analyzing the underground water level data from 1984 to 2002, the following conclusions are arrived: the underground water level changes basically with precipitation; there is a general downward tendency and underground water resources decrease correspondingly; especially the underground water level declines year by year since 1995. Two solutions to mitigate the shortage of water resources are proposed: increasing precipitation through artificial rain enhancement and economizing water resources use.
According to precipitation data from 1951 to 2002, the precipitation distribution characteristics and variation tendency were analyzed. There was great variation in year-to-year precipitation with the maximum being five times greater than the minimum. The seasonal distributions were quite uneven with a general downward trend; especially since 1997 precipitation has been smaller than the normal. By means of monthly precipitation and temperature data from 1951 to 2002 and an empirical formula of land surface evaporation, the land-surface evaporating, evaporating coefficient and available precipitation coefficient were calculated; it is concluded that water resources and precipitation have similar variation characteristics and there occurred frequently droughts in spring in Taian. Through analyzing the underground water level data from 1984 to 2002, the following conclusions are arrived: the underground water level changes basically with precipitation; there is a general downward tendency and underground water resources decrease correspondingly; especially the underground water level declines year by year since 1995. Two solutions to mitigate the shortage of water resources are proposed: increasing precipitation through artificial rain enhancement and economizing water resources use.
2005, 33(4):360-362.
Abstract:
The negative accumulated temperature is an ecological indicator of heat resources in agriculture production in winter. In order to accelerate the agriculture development in frost season and give full play to the land resources, it is essential to find out the geographical distribution characteristics of negative accumulated temperature. Based on the daily mean air temperature of 48 meteorological stations in Liaoning Province from 1961 to 1990, the negative accumulated temperatures for all the stations and the geographical distribution characteristics were statistically calculated and analyzed. The multi-year calculation models of accumulated temperature average using latitude, longitude and altitude by means of the small grid method were developed, and the digital pictures of negative accumulated temperature can be drawn on the ARCGIS platform to improve the analysis precision.
The negative accumulated temperature is an ecological indicator of heat resources in agriculture production in winter. In order to accelerate the agriculture development in frost season and give full play to the land resources, it is essential to find out the geographical distribution characteristics of negative accumulated temperature. Based on the daily mean air temperature of 48 meteorological stations in Liaoning Province from 1961 to 1990, the negative accumulated temperatures for all the stations and the geographical distribution characteristics were statistically calculated and analyzed. The multi-year calculation models of accumulated temperature average using latitude, longitude and altitude by means of the small grid method were developed, and the digital pictures of negative accumulated temperature can be drawn on the ARCGIS platform to improve the analysis precision.
2005, 33(4):363-366.
Abstract:
Based on the soil respiration measurement methods, an introduction was made to the components, main characteristics, measurement principles, a typical measurement process and data output of the LI-8100 Automated Soil CO_2 Flux System. The LI-8100 has the flowing characteristics: high measuring precision; automated, continuous, unattended long-term measurements; fast, convenient, repeatable survey measurements; open path soil CO_2 flux measurements; designed to minimize perturbations within the chamber during measurements; measurements made at or near ambient CO_2 concentrations. The LI-8100 will play an important role in the researches on global carbon cycling.
Based on the soil respiration measurement methods, an introduction was made to the components, main characteristics, measurement principles, a typical measurement process and data output of the LI-8100 Automated Soil CO_2 Flux System. The LI-8100 has the flowing characteristics: high measuring precision; automated, continuous, unattended long-term measurements; fast, convenient, repeatable survey measurements; open path soil CO_2 flux measurements; designed to minimize perturbations within the chamber during measurements; measurements made at or near ambient CO_2 concentrations. The LI-8100 will play an important role in the researches on global carbon cycling.
2005, 33(4):367-369372.
Abstract:
对干湿球系数A与环境温度t的关系进行了研究。结果指出，A不仅与风速有关，也与环境温度有关，如果不考虑风速和环境温度，使用干湿球测湿法获得的测量结果没有使用价值。t〉40℃以后，随着t的升高，使用A的拟合公式计算得到的相对湿度值其误差愈来愈大，在相对湿度较低时情况更为明显。为此提出了在40℃〈t〈80℃范围内A的计算公式。经验证，使用此计算公式获得A值后再计算出相对湿度，其误差小于1．4％。
对干湿球系数A与环境温度t的关系进行了研究。结果指出，A不仅与风速有关，也与环境温度有关，如果不考虑风速和环境温度，使用干湿球测湿法获得的测量结果没有使用价值。t〉40℃以后，随着t的升高，使用A的拟合公式计算得到的相对湿度值其误差愈来愈大，在相对湿度较低时情况更为明显。为此提出了在40℃〈t〈80℃范围内A的计算公式。经验证，使用此计算公式获得A值后再计算出相对湿度，其误差小于1．4％。
2005, 33(4):370-372.
Abstract:
Uncertainty of calibration equipment for humidity instruments (sensors) exerts a great influence on the calibration results of humidity instrument (sensors). According to the province-level calibration centers' humidity calibration equipment, the test and assessment of the uncertainty for the whole calibration equipment were conducted. The error sources, error classification, and the components of the calibration equipment were discussed.
Uncertainty of calibration equipment for humidity instruments (sensors) exerts a great influence on the calibration results of humidity instrument (sensors). According to the province-level calibration centers' humidity calibration equipment, the test and assessment of the uncertainty for the whole calibration equipment were conducted. The error sources, error classification, and the components of the calibration equipment were discussed.
2005, 33(4):373-377.
Abstract:
In order to provide quantitative reference for WAFS's users, selecting the GRIB data in the areas and levels in common use in WAFS products, the numerical analysis and comparison were made of the objective analysis of wind and temperature from the National Meteorological Center and the forecast results of the WAFS (wind, temperature) at the same time in the form of the root-mean-square error (RMSE). The WAFS wind and temperature predictions are usually short-term predictions, which are closer to the objective analysis fields than long-term wind and temperature predictions. The forecasts for low levels are closer to the objective analysis fields than the forecasts for higher levels. In additional, v vector forecast with is superior to u vector, and most of the wind errors come from u vector.
In order to provide quantitative reference for WAFS's users, selecting the GRIB data in the areas and levels in common use in WAFS products, the numerical analysis and comparison were made of the objective analysis of wind and temperature from the National Meteorological Center and the forecast results of the WAFS (wind, temperature) at the same time in the form of the root-mean-square error (RMSE). The WAFS wind and temperature predictions are usually short-term predictions, which are closer to the objective analysis fields than long-term wind and temperature predictions. The forecasts for low levels are closer to the objective analysis fields than the forecasts for higher levels. In additional, v vector forecast with is superior to u vector, and most of the wind errors come from u vector.
2005, 33(4):378-381.
Abstract:
The graphical weather information is necessary for expanding weather service. A method of plotting color-filled contours with random and irregular boundaries is presented. With the method, an ActiveX control with self-contained function was built. By using the ActiveX control, a meteorological information sharing system, which runs on Microsoft Windows, is developed. The ActiveX control provides a useful means for expanding meteorological service and an optional graphical method for meteorological research and operation.
The graphical weather information is necessary for expanding weather service. A method of plotting color-filled contours with random and irregular boundaries is presented. With the method, an ActiveX control with self-contained function was built. By using the ActiveX control, a meteorological information sharing system, which runs on Microsoft Windows, is developed. The ActiveX control provides a useful means for expanding meteorological service and an optional graphical method for meteorological research and operation.
2005, 33(4):382-384.
Abstract:
An objective analysis software for meteorological elements developed under VC environment is described. It makes isoline analysis by means of triangle grids and cubic B-spline curve smoothing,and counter-distance weighting method for interpolation. Some functions of the CxImage graph package were sealed so as to realize the quick generation and storage of graphics in the memory. Through the interface design of data menu, product output list, and information-control list, automatic objective analysis was realized successfully. The software can be used as an independent platform or as a module, and can be operated automatically or manually. The real-time graphic rainfall display across Shandong Province without any manual intervention was realized under Windows. The software has been used in the Shandong provincial-level meteorological service and research.
An objective analysis software for meteorological elements developed under VC environment is described. It makes isoline analysis by means of triangle grids and cubic B-spline curve smoothing,and counter-distance weighting method for interpolation. Some functions of the CxImage graph package were sealed so as to realize the quick generation and storage of graphics in the memory. Through the interface design of data menu, product output list, and information-control list, automatic objective analysis was realized successfully. The software can be used as an independent platform or as a module, and can be operated automatically or manually. The real-time graphic rainfall display across Shandong Province without any manual intervention was realized under Windows. The software has been used in the Shandong provincial-level meteorological service and research.
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.