ISSN 1000-0526
CN 11-2282/P
CN 11-2282/P
Volume 32,Issue 9,2006 Table of Contents
2006, 32(9):3-8.
DOI: 10.7519/j.issn.1000-0526.2006.9.001
Abstract:
Ingredients-Based Methodology (IBM) was applied to forecasting heavy rain of Meiyu front. The basic ingredients of heavy rain is explained by the prime equations of precipitation, and the approach to construct ingredients is also indicated. Furthermore, by analyzing a case, the application of the IBM to the prediction of heavy rain is illustrated. The result indicates that some basic ingredients, such as precipitable water (PW) etc., selected by basic physical mechanism of severe convective weather, have good relationship with the heavy rain in Meiyu front, and the potential prediction of heavy rain can be made by the meteorological process of these basic ingredients.
Ingredients-Based Methodology (IBM) was applied to forecasting heavy rain of Meiyu front. The basic ingredients of heavy rain is explained by the prime equations of precipitation, and the approach to construct ingredients is also indicated. Furthermore, by analyzing a case, the application of the IBM to the prediction of heavy rain is illustrated. The result indicates that some basic ingredients, such as precipitable water (PW) etc., selected by basic physical mechanism of severe convective weather, have good relationship with the heavy rain in Meiyu front, and the potential prediction of heavy rain can be made by the meteorological process of these basic ingredients.
2006, 32(9):9-16.
DOI: 10.7519/j.issn.1000-0526.2006.9.002
Abstract:
A severe hailstorm occurred near Dezhou, Shandong province on 28 June 2003. The synoptic situation, energy field and water vapor content field before the hailfall are analyzed by using the data of MICAPS, Rawinsonde observation and grid-point field from NCEP. The evolution process and the structure of the hail cloud are also analyzed on the basis of two Doppler weather radars. The results show that before hailfall, there is a tongue of high energy at the low level,and negative energy advection or a center of negative energy advection in the mid- and upper-level over the west of the hailfall area. The observation of Doppler radar showed that the supercell storm developed from a singlecell storm with the typical features of the supercell storm. Meanwhile, the moving direction of the supercell storm was about 20° in the right of its dominating wind direction, so it belongs to a right moving supercell storm.
A severe hailstorm occurred near Dezhou, Shandong province on 28 June 2003. The synoptic situation, energy field and water vapor content field before the hailfall are analyzed by using the data of MICAPS, Rawinsonde observation and grid-point field from NCEP. The evolution process and the structure of the hail cloud are also analyzed on the basis of two Doppler weather radars. The results show that before hailfall, there is a tongue of high energy at the low level,and negative energy advection or a center of negative energy advection in the mid- and upper-level over the west of the hailfall area. The observation of Doppler radar showed that the supercell storm developed from a singlecell storm with the typical features of the supercell storm. Meanwhile, the moving direction of the supercell storm was about 20° in the right of its dominating wind direction, so it belongs to a right moving supercell storm.
2006, 32(9):17-22.
DOI: 10.7519/j.issn.1000-0526.2006.9.003
Abstract:
Based on a multi-timescale analysis method—Hilbter-Huang Transform (HHT), inter-annual and inter-decadal variability of the SST in Niňo3 region in the last 100 years is analyzed. The results show that the SST variability involves seven quasi-period oscillations and one century′s climate state. The main period of SST has experienced a significant change in different period. The inter-annual modes of 3—4a and 6—8a have a phase-locked to the ENSO cycle, and the rest of inter-annual and inter-decadal modes contribute significantly to the ENSO events both in amplitude and duration. But the effects of the “cool or warm climate regime” on La Niňa and El Niňo events are not prominent. The “warm” regime is in favor of El Niňo events since 1977 is because the inter-decadal oscillations are very strong in warming phase. It is noteworthy that the amplitudes of three inter-decadal oscillations in warming phase have been weakened since the late 1990s, whose influence on ENSO warm events will be reduced.
Based on a multi-timescale analysis method—Hilbter-Huang Transform (HHT), inter-annual and inter-decadal variability of the SST in Niňo3 region in the last 100 years is analyzed. The results show that the SST variability involves seven quasi-period oscillations and one century′s climate state. The main period of SST has experienced a significant change in different period. The inter-annual modes of 3—4a and 6—8a have a phase-locked to the ENSO cycle, and the rest of inter-annual and inter-decadal modes contribute significantly to the ENSO events both in amplitude and duration. But the effects of the “cool or warm climate regime” on La Niňa and El Niňo events are not prominent. The “warm” regime is in favor of El Niňo events since 1977 is because the inter-decadal oscillations are very strong in warming phase. It is noteworthy that the amplitudes of three inter-decadal oscillations in warming phase have been weakened since the late 1990s, whose influence on ENSO warm events will be reduced.
2006, 32(9):23-27.
DOI: 10.7519/j.issn.1000-0526.2006.9.004
Abstract:
The thermal environment and thermal effect is one of the most important contents in city climate and environment researches. The land surface temperature (LST) is an efficient way to research thermal environmental problem of earth surface. Based on the MODIS data in the middle ten days in July 2005, the LST images are retrieved by the generalized split-window algorithm, the distribution image of the thermal field is made by the maximum value composing method. The conclusion indicates that the high temperature distributes mainly in the Pearl River Delta periphery in the early of calefaction. In addition, the calefaction around the river grows fastest-highest. In full flourish of calefaction, the highest temperature appears mostly around the areas where the densities of river net are high. The urban heat island effect is more evident in urbanization and industrialization cities. These findings accord with the recent development situation in Pearl River Delta, and it will do help to the city planning and construction.
The thermal environment and thermal effect is one of the most important contents in city climate and environment researches. The land surface temperature (LST) is an efficient way to research thermal environmental problem of earth surface. Based on the MODIS data in the middle ten days in July 2005, the LST images are retrieved by the generalized split-window algorithm, the distribution image of the thermal field is made by the maximum value composing method. The conclusion indicates that the high temperature distributes mainly in the Pearl River Delta periphery in the early of calefaction. In addition, the calefaction around the river grows fastest-highest. In full flourish of calefaction, the highest temperature appears mostly around the areas where the densities of river net are high. The urban heat island effect is more evident in urbanization and industrialization cities. These findings accord with the recent development situation in Pearl River Delta, and it will do help to the city planning and construction.
2006, 32(9):28-34.
DOI: 10.7519/j.issn.1000-0526.2006.9.005
Abstract:
To investigate the impact of the urbanization on the city meteorological conditions, the city group of the middle Liaoning was regarded as test area, a case of heavy pollution in winter was chosen and analyzed by means of the mesoscale numerical model (MM5). The results show that MM5 has a good performance to study the impact of the urbanization on the regional meteorological conditions. Furthermore, the impact of the urbanization development on the surface physical parameter makes the wind speed and specific humidity of surface layer decrease while makes the air temperature rise, meanwhile it makes the inversion intensify and deteriorate the local meteorology condition.
To investigate the impact of the urbanization on the city meteorological conditions, the city group of the middle Liaoning was regarded as test area, a case of heavy pollution in winter was chosen and analyzed by means of the mesoscale numerical model (MM5). The results show that MM5 has a good performance to study the impact of the urbanization on the regional meteorological conditions. Furthermore, the impact of the urbanization development on the surface physical parameter makes the wind speed and specific humidity of surface layer decrease while makes the air temperature rise, meanwhile it makes the inversion intensify and deteriorate the local meteorology condition.
2006, 32(9):35-41.
DOI: 10.7519/j.issn.1000-0526.2006.9.006
Abstract:
To investigate the mechanism of the sandstorm,based on the correlation analysis, the establishment of the gale modified index, trends analysis, and moving correlation method, the correlation between Sandstorm in North China and meteorological elements is conducted,utilizing surface observing data from 7 meteorological stations in China during the period of 1954—2000,including monthly rainfall, gale dates, mean monthly temperature and sandstorm frequency. The results show that the correlation coefficient between the sandstorm frequency and rainfall at the same period is negative, but the correlation coefficient between the sandstorm frequency and the previous year rainfall is not obvious, and their extrema are corresponding. The correlation between the sandstorm and gale frequency and gale modified index is positive, the comparison shows that the gale modified index can well indicate the rule of sandstorm. The correlation between it and the previous winter temperature is negative, after eliminated the trend, the negative correlation does not exist, so their correlation is due to their trend. Through 20 years moving correlation analysis, from which the 6 stations show the same trendency, so it shows that their correlation is related to the degree of underlying surface desertification.
To investigate the mechanism of the sandstorm,based on the correlation analysis, the establishment of the gale modified index, trends analysis, and moving correlation method, the correlation between Sandstorm in North China and meteorological elements is conducted,utilizing surface observing data from 7 meteorological stations in China during the period of 1954—2000,including monthly rainfall, gale dates, mean monthly temperature and sandstorm frequency. The results show that the correlation coefficient between the sandstorm frequency and rainfall at the same period is negative, but the correlation coefficient between the sandstorm frequency and the previous year rainfall is not obvious, and their extrema are corresponding. The correlation between the sandstorm and gale frequency and gale modified index is positive, the comparison shows that the gale modified index can well indicate the rule of sandstorm. The correlation between it and the previous winter temperature is negative, after eliminated the trend, the negative correlation does not exist, so their correlation is due to their trend. Through 20 years moving correlation analysis, from which the 6 stations show the same trendency, so it shows that their correlation is related to the degree of underlying surface desertification.
2006, 32(9):42-48.
DOI: 10.7519/j.issn.1000-0526.2006.9.007
Abstract:
Several major weather cases are investigated in terms of thermodynamics and dynamics using the domestic AMDAR(Aircraft Meteorological Data Relay)data. The main results are as follows: (1) The spatial-temporal variable characteristics of the meteorological elements around the airports can be continuously monitored by means of AMDAR data with high spatial-temporal resolution, which is obtained when airplanes are taking off and landing over airports, combined with the other meteorological observations, from which the meso-scale weather systems causing severe convective weathers such as hail can be found, but it is difficult to find from the conventional observations. (2) The AMDAR data are more valuable than those of conventional ones in analyzing and predicting the stable weather (heavy fog). (3) The AMDAR data not only can provide fine indications for now-casting and very short-range forecasting, but also can improve the understandings and predictabilities for the catastrophic weathers in some extents.
Several major weather cases are investigated in terms of thermodynamics and dynamics using the domestic AMDAR(Aircraft Meteorological Data Relay)data. The main results are as follows: (1) The spatial-temporal variable characteristics of the meteorological elements around the airports can be continuously monitored by means of AMDAR data with high spatial-temporal resolution, which is obtained when airplanes are taking off and landing over airports, combined with the other meteorological observations, from which the meso-scale weather systems causing severe convective weathers such as hail can be found, but it is difficult to find from the conventional observations. (2) The AMDAR data are more valuable than those of conventional ones in analyzing and predicting the stable weather (heavy fog). (3) The AMDAR data not only can provide fine indications for now-casting and very short-range forecasting, but also can improve the understandings and predictabilities for the catastrophic weathers in some extents.
2006, 32(9):49-54.
DOI: 10.7519/j.issn.1000-0526.2006.9.008
Abstract:
Aim to the frequent heavy rain and flood in North of Guangxi, using numerical weather forecast products of T213 model and Japan fine-mesh rainfall forecast model, a regional mean rainfall regressive forecast equation for north of Guangxi is set up on the basis of the calculation result of condition number. By an operational test in May and June 2004—2005, the errors of new forecast equation and traditional stepwise regression equation are 6.3569mm, 7.0096mm respectively, and the error of T213 in the corresponding period is 7.9456mm. The forecast capability of the new equation is better than the traditional regressive equation and T213 model, and it can be used widely in the operational weather forecast. Comparing the condition number of two forecast equations, the result shows that the collinearity of the new forecast equation is lower than the traditional stepwise regression equation, whose serious collinearity influences the forecast capability.
Aim to the frequent heavy rain and flood in North of Guangxi, using numerical weather forecast products of T213 model and Japan fine-mesh rainfall forecast model, a regional mean rainfall regressive forecast equation for north of Guangxi is set up on the basis of the calculation result of condition number. By an operational test in May and June 2004—2005, the errors of new forecast equation and traditional stepwise regression equation are 6.3569mm, 7.0096mm respectively, and the error of T213 in the corresponding period is 7.9456mm. The forecast capability of the new equation is better than the traditional regressive equation and T213 model, and it can be used widely in the operational weather forecast. Comparing the condition number of two forecast equations, the result shows that the collinearity of the new forecast equation is lower than the traditional stepwise regression equation, whose serious collinearity influences the forecast capability.
2006, 32(9):55-59.
DOI: 10.7519/j.issn.1000-0526.2006.9.009
Abstract:
In order to discuss the effect of ENSO on the cyclone which endanger Guangdong, the relationships between Accumulated Cyclone Energy (ACE) and other variables of the tropical cyclones entering the Guangdong Area and ENSO are analyzed during the period of 1950—2003 by using statistical method. It is found that the response of the tropical cyclones affecting Guangdong to ENSO is very weak in year, and it shows significant seasonal differences. During the months from June to August, positive correlation can be found between the cyclones and Niňo3.4 indices, but negative correlation is obvious in October. Besides, the intensity, number and lifetime of the tropical cyclones occurring in October indicates greater negative correlation with ENSO. In other words, more cyclones are expected in La Nina years with longer life cycles, greater storm strengths and greater destructiveness, but fewer cyclones in El Nino years with shorter life cycles and less destructiveness. The result also shows that ACE index has a good clue to forecast the tropical cyclones affecting Guangdong.
In order to discuss the effect of ENSO on the cyclone which endanger Guangdong, the relationships between Accumulated Cyclone Energy (ACE) and other variables of the tropical cyclones entering the Guangdong Area and ENSO are analyzed during the period of 1950—2003 by using statistical method. It is found that the response of the tropical cyclones affecting Guangdong to ENSO is very weak in year, and it shows significant seasonal differences. During the months from June to August, positive correlation can be found between the cyclones and Niňo3.4 indices, but negative correlation is obvious in October. Besides, the intensity, number and lifetime of the tropical cyclones occurring in October indicates greater negative correlation with ENSO. In other words, more cyclones are expected in La Nina years with longer life cycles, greater storm strengths and greater destructiveness, but fewer cyclones in El Nino years with shorter life cycles and less destructiveness. The result also shows that ACE index has a good clue to forecast the tropical cyclones affecting Guangdong.
2006, 32(9):60-66.
DOI: 10.7519/j.issn.1000-0526.2006.9.010
Abstract:
Based on the new generation weather radar data in Guilin, a severe squall line event ahead of a front occurred in Guangxi on 5, May 2005 is analyzed to study the evolution of the squall and its convective cell. The results show that this squall line is a combination of follow-up type and consecutive type. The meso-scale convective cell in squall line causes severe convective wind. Before convective cell move into squall line, it can become a mature supercell with TBSS and BWER features. The vertical accumulated liquid water content can get 70kg·m-2, and produce local great hail. Based on the VIL value, the location of most severe strom can be found and the heavy hailstorm can be identified, the nowcasting of severe convective weather can be made.
Based on the new generation weather radar data in Guilin, a severe squall line event ahead of a front occurred in Guangxi on 5, May 2005 is analyzed to study the evolution of the squall and its convective cell. The results show that this squall line is a combination of follow-up type and consecutive type. The meso-scale convective cell in squall line causes severe convective wind. Before convective cell move into squall line, it can become a mature supercell with TBSS and BWER features. The vertical accumulated liquid water content can get 70kg·m-2, and produce local great hail. Based on the VIL value, the location of most severe strom can be found and the heavy hailstorm can be identified, the nowcasting of severe convective weather can be made.
2006, 32(9):67-70.
DOI: 10.7519/j.issn.1000-0526.2006.9.011
Abstract:
The measurement error due to the blocking effect is discussed when the anemometer is tested in the wind-tunnel experiment, whose purpose is to explore an arithmetic of blocking correction coefficient with universal significance. Taking the book named as “test in the wind-tunnel of low-speed” as a basis, according to the country′s measuring amount value, the solid cylindrical blocking revision method in the wind-tunnel of two dimension is transplanted, derived, and became a method with the wind speed transducer blocking coefficient, so mathematical measurement model is set up,and then,the mathematical measurement model is verified to the wind speed transducer of the automatic weather stations in Guangdong Province, and the ideal result is obtained.
The measurement error due to the blocking effect is discussed when the anemometer is tested in the wind-tunnel experiment, whose purpose is to explore an arithmetic of blocking correction coefficient with universal significance. Taking the book named as “test in the wind-tunnel of low-speed” as a basis, according to the country′s measuring amount value, the solid cylindrical blocking revision method in the wind-tunnel of two dimension is transplanted, derived, and became a method with the wind speed transducer blocking coefficient, so mathematical measurement model is set up,and then,the mathematical measurement model is verified to the wind speed transducer of the automatic weather stations in Guangdong Province, and the ideal result is obtained.
2006, 32(9):71-76.
DOI: 10.7519/j.issn.1000-0526.2006.9.012
Abstract:
Using routine ground observation data, T213 and automatic observation station data, diagnostic analyses are made on the causes and moist potential vorticity for the twice sudden drop temperature in a rare cold wave event from 10 to 11 march 2005 in Hubei Province. The results show that the strong cold air flowing into a warm trough induced the first temperature sudden drop, but the second was resulted in the upper cold advection passing downward and the surface precipitation band moving from west to east. The spatial-temporal evolvement of mpv2 being the horizontal component of moist potential vorticity(MPV) has a good relationship with the development,moving and the temperature sudden drop in the severe cold air.
Using routine ground observation data, T213 and automatic observation station data, diagnostic analyses are made on the causes and moist potential vorticity for the twice sudden drop temperature in a rare cold wave event from 10 to 11 march 2005 in Hubei Province. The results show that the strong cold air flowing into a warm trough induced the first temperature sudden drop, but the second was resulted in the upper cold advection passing downward and the surface precipitation band moving from west to east. The spatial-temporal evolvement of mpv2 being the horizontal component of moist potential vorticity(MPV) has a good relationship with the development,moving and the temperature sudden drop in the severe cold air.
2006, 32(9):74-89.
DOI: 10.7519/j.issn.1000-0526.2006.9.014
Abstract:
According to the frost index defined by the minimum air temperature ≤0℃, based on the method of modern times climate diagnosis, the climatic change of the anomalous first and last date of frost are analyzed with 4 meteorological stations′ data of daily minimum temperature over the middle reaches of the Yarlung Zangbo River in Tibet from 1961 to 2000. The results show that the first frost appeared late, while the last frost ended early, so that the frostless period was extended significantly in the eastern part of Yarlung Zangbo River basin in the past 40 years, but the tendency in Gyantse was on the contrary. In 1970s and 1990s, because the first frost appeared late and the last frost ended early made the growth season in the eastern part of Brahmaputra basin prolong, especially in 1990s. On the other hand, ending frost date in Gyantse presented prolonged tendency per decade in the west of Yarlung Zangbo River basin. In addition, it is found that the frequency of exceptional first frost date was 2 or 3 times, especially it was the most in Tesdang, meanwhile the frequency of anomalous ending frost date was 1 or 4 times, it was the most in Gyantse. The abrupt change of the first date and the ending date of frost only occurred in Tesdang.
According to the frost index defined by the minimum air temperature ≤0℃, based on the method of modern times climate diagnosis, the climatic change of the anomalous first and last date of frost are analyzed with 4 meteorological stations′ data of daily minimum temperature over the middle reaches of the Yarlung Zangbo River in Tibet from 1961 to 2000. The results show that the first frost appeared late, while the last frost ended early, so that the frostless period was extended significantly in the eastern part of Yarlung Zangbo River basin in the past 40 years, but the tendency in Gyantse was on the contrary. In 1970s and 1990s, because the first frost appeared late and the last frost ended early made the growth season in the eastern part of Brahmaputra basin prolong, especially in 1990s. On the other hand, ending frost date in Gyantse presented prolonged tendency per decade in the west of Yarlung Zangbo River basin. In addition, it is found that the frequency of exceptional first frost date was 2 or 3 times, especially it was the most in Tesdang, meanwhile the frequency of anomalous ending frost date was 1 or 4 times, it was the most in Gyantse. The abrupt change of the first date and the ending date of frost only occurred in Tesdang.
14 Variation Characteristics of Sunshine Duration and Wind Velocity in Naqu,Xizang for Recent 40 Years
2006, 32(9):77-83.
DOI: 10.7519/j.issn.1000-0526.2006.9.013
Abstract:
Based on the conventional statistic methods and Mexican hat wavelet, the geographical distribution of sunshine duration and wind velocity and their annually, and interdecadal changes in recent 40 years are analyzed using daily sunshine duration and wind velocity data of 6 stations in Naqu from 1961 to 2000. The main results are as follows: (1) In the most of places of Naqu, the annual sunshine duration are more than 2550 hours and average wind velocity are higher than 4m·s-1. (2) The sunshine duration in spring, summer, autumn, winter, growing season (from May to September) and a year all decreased in recent 40 years. (3) The wind velocity in winter decreased and the wind velocity in other 5 periods all increased. (4) The sunshine duration and wind velocity in 1990′s were smaller than that in 1980′s for all 6 periods. (5) The sunshine duration and wind velocity from 2000 to 2005 could continue to decrease.
Based on the conventional statistic methods and Mexican hat wavelet, the geographical distribution of sunshine duration and wind velocity and their annually, and interdecadal changes in recent 40 years are analyzed using daily sunshine duration and wind velocity data of 6 stations in Naqu from 1961 to 2000. The main results are as follows: (1) In the most of places of Naqu, the annual sunshine duration are more than 2550 hours and average wind velocity are higher than 4m·s-1. (2) The sunshine duration in spring, summer, autumn, winter, growing season (from May to September) and a year all decreased in recent 40 years. (3) The wind velocity in winter decreased and the wind velocity in other 5 periods all increased. (4) The sunshine duration and wind velocity in 1990′s were smaller than that in 1980′s for all 6 periods. (5) The sunshine duration and wind velocity from 2000 to 2005 could continue to decrease.
2006, 32(9):90-94.
DOI: 10.7519/j.issn.1000-0526.2006.9.015
Abstract:
Based on the data from weather stations in Fushun, the climatic characters and causes of anomalous cold winter are analyzed. It is found that there is a cold period with the lowest temperature under -30℃ in the years of anomalous cold winter, as well as more snowfall and deep snow cover after global warming. By using the average ground temperature in deep level, sunspot activity, general circulation data, it can be found that the abnormal cold winter often occurs around the peak value year of macula activity, having a positive correlation with the average ground temperature at 0.8m below the surface during the prophase March-November, and the other properties are that the departure field of 500hPa geopotential height over Europe and Asia in northern hemisphere shows positive(negative) departure in west (east), the East Asia trough will establish steadily, and the general circulation appears as E pattern over Atlantic-Eurasia.
Based on the data from weather stations in Fushun, the climatic characters and causes of anomalous cold winter are analyzed. It is found that there is a cold period with the lowest temperature under -30℃ in the years of anomalous cold winter, as well as more snowfall and deep snow cover after global warming. By using the average ground temperature in deep level, sunspot activity, general circulation data, it can be found that the abnormal cold winter often occurs around the peak value year of macula activity, having a positive correlation with the average ground temperature at 0.8m below the surface during the prophase March-November, and the other properties are that the departure field of 500hPa geopotential height over Europe and Asia in northern hemisphere shows positive(negative) departure in west (east), the East Asia trough will establish steadily, and the general circulation appears as E pattern over Atlantic-Eurasia.
2006, 32(9):95-98.
DOI: 10.7519/j.issn.1000-0526.2006.9.016
Abstract:
Based on the visual fortran and visual basic programming language and the related algorithm, precipitation software system of the Doppler radar quantitative measurement to Jiuquxi,Mt. Wuyi is developed with the 28 processes echo data of Jianyang CINRAD radar from 2002 to 2004, and the precipitation data of the 27 surface meteorological stations in the mid-north Fujian, and the 10 automatic rainfall stations data of Jiuquxi in the Mt. Wuyi. The 9 groups optimal A and b value of three kind of different precipitation types in three different regions are determined. The effect of the three kinds of precipitation products in precipitation quantitative measurement is more obvious than that of the PUP of Jianyang CINRAD radar.
Based on the visual fortran and visual basic programming language and the related algorithm, precipitation software system of the Doppler radar quantitative measurement to Jiuquxi,Mt. Wuyi is developed with the 28 processes echo data of Jianyang CINRAD radar from 2002 to 2004, and the precipitation data of the 27 surface meteorological stations in the mid-north Fujian, and the 10 automatic rainfall stations data of Jiuquxi in the Mt. Wuyi. The 9 groups optimal A and b value of three kind of different precipitation types in three different regions are determined. The effect of the three kinds of precipitation products in precipitation quantitative measurement is more obvious than that of the PUP of Jianyang CINRAD radar.
2006, 32(9):99-105.
DOI: 10.7519/j.issn.1000-0526.2006.9.017
Abstract:
The characteristics of multi-timescale temperature change in Puyang, Henan Province and its effects on grain production caused by the warming-up climate are analyzed. The results are as follows. The temperatures in winter and in summer float respectively with the value 0.23—0.46℃/10a and -0.05—0.11℃/10a, while the annual average is 0.14℃/10a. The annual high temperature (daily maximum temperature as high as or higher than 35℃)/low temperature(daily minimum temperature as low as or lower than -10℃) day decrease at 3.36 days per 10-year and 2.35 days per 10-year. The first day when the average daily temperature keeps above 0℃ steadily shifts 4.91 days earlier per 10-year, while the last day shifts 1.02 days later per 10-year. Besides, the last day when the average daily temperature keeps above 20℃ steadily shifts 2.0 days later per 10-year. There have been 17 warm winters ever since 1987 in puyang, with the most typical ones happening after 1995.The breed of wheat introduced to Puyang gets weaker in winter nature with postponed sowing date, shorter overwintering period and longer growing period. As a consequence, plant diseases and insect pests tend to be more serious and much agricultural chemical and fertilizer have to be applied. It shows that the local climate is changing with the tendency of warmer winter and cooler summer. Therefore, the damage caused by high or low temperature decreases, the efficiency of accumulated temperature increases and plants obtain a longer growing and milking period. Ever since the mid-1990s, more events of unusual warm winter happen. The last ten-year are the warmest one for the last 50 years. Mean while, the annual change of the average temperature in winter is with larger amplitude, while the temperature in spring tends to be poor in stability. Although there exist more advantages for the local grain production in warmer climate, disadvantages stand out at the same time. It is necessary to study how to ensure grain safety by pursuing gains and avoiding losses.
The characteristics of multi-timescale temperature change in Puyang, Henan Province and its effects on grain production caused by the warming-up climate are analyzed. The results are as follows. The temperatures in winter and in summer float respectively with the value 0.23—0.46℃/10a and -0.05—0.11℃/10a, while the annual average is 0.14℃/10a. The annual high temperature (daily maximum temperature as high as or higher than 35℃)/low temperature(daily minimum temperature as low as or lower than -10℃) day decrease at 3.36 days per 10-year and 2.35 days per 10-year. The first day when the average daily temperature keeps above 0℃ steadily shifts 4.91 days earlier per 10-year, while the last day shifts 1.02 days later per 10-year. Besides, the last day when the average daily temperature keeps above 20℃ steadily shifts 2.0 days later per 10-year. There have been 17 warm winters ever since 1987 in puyang, with the most typical ones happening after 1995.The breed of wheat introduced to Puyang gets weaker in winter nature with postponed sowing date, shorter overwintering period and longer growing period. As a consequence, plant diseases and insect pests tend to be more serious and much agricultural chemical and fertilizer have to be applied. It shows that the local climate is changing with the tendency of warmer winter and cooler summer. Therefore, the damage caused by high or low temperature decreases, the efficiency of accumulated temperature increases and plants obtain a longer growing and milking period. Ever since the mid-1990s, more events of unusual warm winter happen. The last ten-year are the warmest one for the last 50 years. Mean while, the annual change of the average temperature in winter is with larger amplitude, while the temperature in spring tends to be poor in stability. Although there exist more advantages for the local grain production in warmer climate, disadvantages stand out at the same time. It is necessary to study how to ensure grain safety by pursuing gains and avoiding losses.
2006, 32(9):106-110.
DOI: 10.7519/j.issn.1000-0526.2006.9.018
Abstract:
Utilizing the theory on calamity study and taking pasture of Qinghai as an example, the factors inducing snow disaster in Qinghai-Tibet plateau are analyzed. Based on the Geographical Information Database (GIS), a synthetical identification snow model is constructed to monitor quickly the snow disaster after a snow, and then, the trend of snow disaster is forecasted dynamically, finally the estimation to disaster is conducted. The results show that during the processes of forming the snow disasters, in addition to the function of snow cover, the fragility of environment suffering disaster and sensitivity of carrier disaster play important roles. The advice which protect pasture and strengthen animal husbandry is given to decrease the damage of snow disaster. At last, using the synthetical forecasting model of snow disaster, the snow disaster forecast in Qinghai is made. The result shows that the model has potential value of application.
Utilizing the theory on calamity study and taking pasture of Qinghai as an example, the factors inducing snow disaster in Qinghai-Tibet plateau are analyzed. Based on the Geographical Information Database (GIS), a synthetical identification snow model is constructed to monitor quickly the snow disaster after a snow, and then, the trend of snow disaster is forecasted dynamically, finally the estimation to disaster is conducted. The results show that during the processes of forming the snow disasters, in addition to the function of snow cover, the fragility of environment suffering disaster and sensitivity of carrier disaster play important roles. The advice which protect pasture and strengthen animal husbandry is given to decrease the damage of snow disaster. At last, using the synthetical forecasting model of snow disaster, the snow disaster forecast in Qinghai is made. The result shows that the model has potential value of application.
2006, 32(9):116-120.
DOI: 10.7519/j.issn.1000-0526.2006.9.020
Abstract:
Based on some phenomena of a complex failure in ZhouShan CINRAD-SB transmitter during the first running period, combining with repairing experiences of electronic equipments, the failure source and some electronic circuits of other failure units induced by the former failure are analyzed, especially, some correlative principle failure diagrams are drawn, the process of repairing these failures was in detail introduced on IC chip/electron-element. In fact, these principle failure diagrams and repairing experiences are useful to diagnose failures of CINRAD-SB transmitter on IC chip/electron-element. In the end, as it was the fact that transmitter high voltage shorting-circuit frequently happened during the first period, some suggestions to protect from the similar failures taking place are put forward.
Based on some phenomena of a complex failure in ZhouShan CINRAD-SB transmitter during the first running period, combining with repairing experiences of electronic equipments, the failure source and some electronic circuits of other failure units induced by the former failure are analyzed, especially, some correlative principle failure diagrams are drawn, the process of repairing these failures was in detail introduced on IC chip/electron-element. In fact, these principle failure diagrams and repairing experiences are useful to diagnose failures of CINRAD-SB transmitter on IC chip/electron-element. In the end, as it was the fact that transmitter high voltage shorting-circuit frequently happened during the first period, some suggestions to protect from the similar failures taking place are put forward.
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ISSN:1000-0526 CN:11-2282/P