ISSN 1000-0526
CN 11-2282/P
CN 11-2282/P
Volume 35,Issue 12,2009 Table of Contents
2009, 35(12):3-11.
DOI: 10.7519/j.issn.1000-0526.2009.12.001
Abstract:
Observation shows that the complex of stratiform and embedded convecti ve percipitation has its own unique thermal and dynamic structure, and the preci pitation process has its own characteristics. However, the numerical study of real cases has been published much less so far. In this paper, a case on the 28 September 2007 complex of stratiform clouds and embedde d convective clouds in North China is simulated by using the WRFARW model. It shows that, the clouds are weakened by the shear line, and formed by the develop ment ofstratiform clouds. It also reveals that the complex of stratiform clouds and embedded convective clouds is not only the comp lex of clouds with different shapes, but also the complex of different microphys ical processes. And the largescale convergence on the middle level and the cor responding uniform updraft make the stratiform clouds develop, while the dramatic fluctuations of updraft lead to embedded convective clouds, which may be initiated and supported by conditional symmetric instability.
Observation shows that the complex of stratiform and embedded convecti ve percipitation has its own unique thermal and dynamic structure, and the preci pitation process has its own characteristics. However, the numerical study of real cases has been published much less so far. In this paper, a case on the 28 September 2007 complex of stratiform clouds and embedde d convective clouds in North China is simulated by using the WRFARW model. It shows that, the clouds are weakened by the shear line, and formed by the develop ment ofstratiform clouds. It also reveals that the complex of stratiform clouds and embedded convective clouds is not only the comp lex of clouds with different shapes, but also the complex of different microphys ical processes. And the largescale convergence on the middle level and the cor responding uniform updraft make the stratiform clouds develop, while the dramatic fluctuations of updraft lead to embedded convective clouds, which may be initiated and supported by conditional symmetric instability.
2009, 35(12):12-20.
DOI: 10.7519/j.issn.1000-0526.2009.12.002
Abstract:
The experiment of Shenyang Doppler radar data assimilation was mad e using WRF3DVAR system. The quality control system of Doppler radar data was developed. The 3DVAR system is able to assimilate both radial winds and reflecti vity directly, [JP2]not only can retrieve mesoscale 3D meteorological elemen t fields but also can offer initial fields to model. Thecan retrieve the mesoscale 3D structure of convective system in cold vortex well using synoptic sca le data as background field. The surface strong convective divergent flow and vo rtex in the middle troposphere retrieved were in accord with conceptual model an d th e wind fields retrieved were closed to surface observations. The meteorological element fields which have assimilated Doppler radar data can be offered to fore casting operation as real time analysis for they include mesoscale weather syste m. After assimilating radar case data of cold vortex over Northeast China, the model forecasts improved slightly for mesoscale and small scale convective syst em. Assimilating radar data made positive effects on model forecasts in general.
The experiment of Shenyang Doppler radar data assimilation was mad e using WRF3DVAR system. The quality control system of Doppler radar data was developed. The 3DVAR system is able to assimilate both radial winds and reflecti vity directly, [JP2]not only can retrieve mesoscale 3D meteorological elemen t fields but also can offer initial fields to model. Thecan retrieve the mesoscale 3D structure of convective system in cold vortex well using synoptic sca le data as background field. The surface strong convective divergent flow and vo rtex in the middle troposphere retrieved were in accord with conceptual model an d th e wind fields retrieved were closed to surface observations. The meteorological element fields which have assimilated Doppler radar data can be offered to fore casting operation as real time analysis for they include mesoscale weather syste m. After assimilating radar case data of cold vortex over Northeast China, the model forecasts improved slightly for mesoscale and small scale convective syst em. Assimilating radar data made positive effects on model forecasts in general.
2009, 35(12):21-29.
DOI: 10.7519/j.issn.1000-0526.2009.12.003
Abstract:
The role played by environmental background and inner core in the changes of intensity o f Typhoon Neoguri is documented by using observed track data, NCEP Final Analysi s, NOAA OI SST weekly means and FY satellite water vapor images. The results sho w that (1) the storm weakening is closely related to the vertical wind shears a nd sea surface temperature. The vertical wind shears increase in magnitude to about 10m/s, and the Maximum Potential Intensity (MPI) decreases when the system moves over a cool tongue of water, the intensification comes to an end; (2) The breakdown and recovery of eyewall revealed by vapor images, are consistent with intensity changes. The breakdown (recovery) of eyewall leads to the storm weakening (deepening).
The role played by environmental background and inner core in the changes of intensity o f Typhoon Neoguri is documented by using observed track data, NCEP Final Analysi s, NOAA OI SST weekly means and FY satellite water vapor images. The results sho w that (1) the storm weakening is closely related to the vertical wind shears a nd sea surface temperature. The vertical wind shears increase in magnitude to about 10m/s, and the Maximum Potential Intensity (MPI) decreases when the system moves over a cool tongue of water, the intensification comes to an end; (2) The breakdown and recovery of eyewall revealed by vapor images, are consistent with intensity changes. The breakdown (recovery) of eyewall leads to the storm weakening (deepening).
2009, 35(12):30-36.
DOI: 10.7519/j.issn.1000-0526.2009.12.004
Abstract:
Largescale environmental vapor flux plays a very important role in th e genesis, development and dissipation of tropical cyclones. A regression method is developed to get the relationship between radiances measured by the Advanced Microwave Sounding Unit (AMSU) and water vapor fluxes. The method uses the brig htness temperatures at three channels 18, 19 and 20 of AMSUB, which are cente red around the 183.3GHz water vapor line, and the water vapor flux is derived fr om the calculation of stream function. With the regression, it is found that the brightness temperatures at the corresponding channel 183.3±7GHz, 183.3±3GHz a nd 183.3±1GHz decrease exponentially with water vapor flux on the upper, middle and lower troposphere, respectively. Then, Typhoon Matsa (0509) is illustrated to analyze the distribution and evolvement of the surrounding water vapor. By this exponential algorithm, there are great water vapor transportations as indicate d by the water vapor channel brightness temperatures. And it shows the importanc e of the environmental water vapor in the development of tropical cyclones. Addi tionally, the incoming vapor collected around the cyclone is mainly from southwe stern transportation, but the water vapor from other routes could not be ignored , especially the eastern and the southeastern.
Largescale environmental vapor flux plays a very important role in th e genesis, development and dissipation of tropical cyclones. A regression method is developed to get the relationship between radiances measured by the Advanced Microwave Sounding Unit (AMSU) and water vapor fluxes. The method uses the brig htness temperatures at three channels 18, 19 and 20 of AMSUB, which are cente red around the 183.3GHz water vapor line, and the water vapor flux is derived fr om the calculation of stream function. With the regression, it is found that the brightness temperatures at the corresponding channel 183.3±7GHz, 183.3±3GHz a nd 183.3±1GHz decrease exponentially with water vapor flux on the upper, middle and lower troposphere, respectively. Then, Typhoon Matsa (0509) is illustrated to analyze the distribution and evolvement of the surrounding water vapor. By this exponential algorithm, there are great water vapor transportations as indicate d by the water vapor channel brightness temperatures. And it shows the importanc e of the environmental water vapor in the development of tropical cyclones. Addi tionally, the incoming vapor collected around the cyclone is mainly from southwe stern transportation, but the water vapor from other routes could not be ignored , especially the eastern and the southeastern.
5 Possible Reasons for Northward Shift of Meiyu Belt
in YangtzeHuaihe River Region During 2000-2005
2009, 35(12):37-43.
DOI: 10.7519/j.issn.1000-0526.2009.12.005
Abstract:
Since 2000, the probability of deficit Meiyu year has increased and Meiyu rainfall has stepped into a period of decrease in the Yangtze River regio n. The rainfall observational data show that the axis of Meiyu belt has shifted 2 degrees in latitude northwards and the rainfall has increased by 20% in the Huaihe River region during 2000-2005 in comparison with that of 1971-1999. Therefore, a ccording to the NCEP/NCAR reanalysis data, the anomaly situation of general circulation has been analyzed from the aspects of 200hPa wind field, 500hPa potential height field, 850hPa relative vorticity field, vertical velocity, apparentpparent water vapor sink (Q2) for the recent 6 years. In the end, the research s hows that all of the northward movement of the ridge line location of the West Pacific subtropical high, the reinforcement of the East Asian summer monsoon circulation and the weakening of cold air from the north have contributed to the northward shift of Meiyu belt during 2000-2005 in the YangtzeHuaihe River region.
Since 2000, the probability of deficit Meiyu year has increased and Meiyu rainfall has stepped into a period of decrease in the Yangtze River regio n. The rainfall observational data show that the axis of Meiyu belt has shifted 2 degrees in latitude northwards and the rainfall has increased by 20% in the Huaihe River region during 2000-2005 in comparison with that of 1971-1999. Therefore, a ccording to the NCEP/NCAR reanalysis data, the anomaly situation of general circulation has been analyzed from the aspects of 200hPa wind field, 500hPa potential height field, 850hPa relative vorticity field, vertical velocity, apparentpparent water vapor sink (Q2) for the recent 6 years. In the end, the research s hows that all of the northward movement of the ridge line location of the West Pacific subtropical high, the reinforcement of the East Asian summer monsoon circulation and the weakening of cold air from the north have contributed to the northward shift of Meiyu belt during 2000-2005 in the YangtzeHuaihe River region.
2009, 35(12):44-50.
DOI: 10.7519/j.issn.1000-0526.2009.12.006
Abstract:
The characteristics of tropical cyclone (TC) over the western North Pac ific (WNP) in 2008 were reviewed, and its causation was analyzed. The results sh owed that the number of TC was less than the mean, the formative location was more concentrated and further west; the landing number was more than the normal, the first landed earlier, the landing position of TC was further south and landing time was more focused. The analyses of the main factors resulting in these anomalies showed that compared with means, the characteristics of the subtropical high were abnormal during the period of TC activity, including its area, strength, ridge position etc. which were unfavorable to the genesis and development of TC. And the anomaly distribution of important factors, such as the monsoon trough, vertical wind shear, sea surface temperature and OLR, was not favorable to the genesis of TC in the eastern WNP, which led to the decrease of TC number and the westward movement of genesis location.
The characteristics of tropical cyclone (TC) over the western North Pac ific (WNP) in 2008 were reviewed, and its causation was analyzed. The results sh owed that the number of TC was less than the mean, the formative location was more concentrated and further west; the landing number was more than the normal, the first landed earlier, the landing position of TC was further south and landing time was more focused. The analyses of the main factors resulting in these anomalies showed that compared with means, the characteristics of the subtropical high were abnormal during the period of TC activity, including its area, strength, ridge position etc. which were unfavorable to the genesis and development of TC. And the anomaly distribution of important factors, such as the monsoon trough, vertical wind shear, sea surface temperature and OLR, was not favorable to the genesis of TC in the eastern WNP, which led to the decrease of TC number and the westward movement of genesis location.
2009, 35(12):51-57.
DOI: 10.7519/j.issn.1000-0526.2009.12.007
Abstract:
With the NCEP reanalysis data, the cumulus convect ive latent heating and the sea surface sensible heat flux in the cours e of the development of Typhoon FungWong are analyzed. It shows that through t he airsea interaction, the sensible heat release strengthened the sea surface wind and tropospheric vor ticity, which may be the possible cause for the initial low pressure of typhoon; the cumulus convective latent heat not only heated the center of typhoon but al so reinforced the ascending motion at middle levels,thereby made it increase a nd develop. The convective condensation latent heat is considered to be the majo r thermal and dynamic factor for the development of Typhoon Fungwong.
With the NCEP reanalysis data, the cumulus convect ive latent heating and the sea surface sensible heat flux in the cours e of the development of Typhoon FungWong are analyzed. It shows that through t he airsea interaction, the sensible heat release strengthened the sea surface wind and tropospheric vor ticity, which may be the possible cause for the initial low pressure of typhoon; the cumulus convective latent heat not only heated the center of typhoon but al so reinforced the ascending motion at middle levels,thereby made it increase a nd develop. The convective condensation latent heat is considered to be the majo r thermal and dynamic factor for the development of Typhoon Fungwong.
2009, 35(12):58-64.
DOI: 10.7519/j.issn.1000-0526.2009.12.008
Abstract:
The west and north parts of Beijing are mountainous areas and the urban island e ffect is obvious in Beijing, which can influence the distributions and intensi ty of the rainfall. Using the intensified observation data including wind profil e data, wind and temperature elements of surface automatic weather stations, th e vertical vapor and temperature distributions observed by surface microwave rad iometer, the evolvement and interaction in the temperature, wind and humidity of the Mesoβ torrential rain occurring in the afternoon on J uly 24, 2006, in Beijing area are studied and it shows how the system cold front is influenced by topography a nd urban island of Beijing， and then the different rainfall centers are form ed. According to the analysis it is concluded that, the cold front influenced the central part of Beijing along a route from northeast to southwest because of the local topography, and when the cold air is obvious the strong rainfall always occurs at the central urban areas with higher temperature. Meanwhile the rainfall center is prone to form in the area of dense anomalous tem perature isolines and in the direction the cold front moves. Wind shear convergence between the southeast wind from the plain and the north wind from the mountains becomes distinct when the cold front arrived near the west mountain, and at the same time the lifting effect of the southeast wind from the plain by mountains strengthened, which is the disturbance cause of the rainstorm. The upward propagation of surface shear convergence is the dynamical support for the rainstor m. The latent heat release changed the temperature distribution during the rains torm, which led to the enhancement of southeast wind which brought vapor to the rainstorm.
The west and north parts of Beijing are mountainous areas and the urban island e ffect is obvious in Beijing, which can influence the distributions and intensi ty of the rainfall. Using the intensified observation data including wind profil e data, wind and temperature elements of surface automatic weather stations, th e vertical vapor and temperature distributions observed by surface microwave rad iometer, the evolvement and interaction in the temperature, wind and humidity of the Mesoβ torrential rain occurring in the afternoon on J uly 24, 2006, in Beijing area are studied and it shows how the system cold front is influenced by topography a nd urban island of Beijing， and then the different rainfall centers are form ed. According to the analysis it is concluded that, the cold front influenced the central part of Beijing along a route from northeast to southwest because of the local topography, and when the cold air is obvious the strong rainfall always occurs at the central urban areas with higher temperature. Meanwhile the rainfall center is prone to form in the area of dense anomalous tem perature isolines and in the direction the cold front moves. Wind shear convergence between the southeast wind from the plain and the north wind from the mountains becomes distinct when the cold front arrived near the west mountain, and at the same time the lifting effect of the southeast wind from the plain by mountains strengthened, which is the disturbance cause of the rainstorm. The upward propagation of surface shear convergence is the dynamical support for the rainstor m. The latent heat release changed the temperature distribution during the rains torm, which led to the enhancement of southeast wind which brought vapor to the rainstorm.
2009, 35(12):65-73.
DOI: 10.7519/j.issn.1000-0526.2009.12.009
Abstract:
In order to make use of AMDAR data better, a feasible observation data quality c ontrol module should be designed to make sure AMDAR data used in the meteorologi cal research and operation with a higher quality. The AMDAR QC module is brought forward consulting the characteristics of AMDAR. Many quality control tech niques are integrated into the QC module, such as the station extreme value check， the interior consistency check, the consistence ch eck w ith the first guess, the temporal consistency check, the space consistency check , th e decisionmaking algorithm, the statistic and feedback technique. The AMDA R data quality control module has been applied into AMDAR data in August of 2007 . Subjective verification result shows that error information in the observation can be distinguished effectively from the AMDAR data.
In order to make use of AMDAR data better, a feasible observation data quality c ontrol module should be designed to make sure AMDAR data used in the meteorologi cal research and operation with a higher quality. The AMDAR QC module is brought forward consulting the characteristics of AMDAR. Many quality control tech niques are integrated into the QC module, such as the station extreme value check， the interior consistency check, the consistence ch eck w ith the first guess, the temporal consistency check, the space consistency check , th e decisionmaking algorithm, the statistic and feedback technique. The AMDA R data quality control module has been applied into AMDAR data in August of 2007 . Subjective verification result shows that error information in the observation can be distinguished effectively from the AMDAR data.
2009, 35(12):74-82.
DOI: 10.7519/j.issn.1000-0526.2009.12.010
Abstract:
Based on the conventional surface and upper data, NCEP 1°×1° reanal ysis data of every 6h, in terms of the synoptic principle and the dynamic diag nosis, the cold wave during 26 December 2008 has been analyzed. The resu lts are as follows: The cold wave occurred when the European ridge developed in tensely and moved eastwards, and the zonal circulation changed into the meridion al one in the middlehigh latitude in the Northern Hemisphere. The northerly wi nd in front of the ridge moved southwards. The vorticity of the transverse tr ough in the west was larger than that in the east. Both the negative variation o f the heightlocated in the southeast part in front of the trough and the posit ive variation of height behind the trough were favorable to t he revising of the transverse trough. The polar vortex and the revising transver se trough get together causing the deepening of the trough. Meanwhile, the cold air strengthened and invaded to the south. The ridge impulsed by the trough move d southeastwards and broke down gradually. Afterwards, the northerly wind change d into the northwesterly wind, which led to this coldwave process. The main re a son for the rapid air temperature decrease was the intense cold advection. The f ormation of the strong wind was correlated with not only the cold advection but also the upper disseminated momentum. There were obvious differences of the circ ulation and characteristics of the physical quantities between the rainfall and the heavy snowfall in the Shandong Peninsula. The rainfall is induced by coldw arm air converging, the heavy snowfall is caused by cold flow and difference of sea land distribution and orographic uplift. T639 model and ECMWF and Japan models , espec ially for ECMWF model, have good performances for the evolvement and adjustment of atmospheric circulation situation in the Asia middle and high latitude area.
Based on the conventional surface and upper data, NCEP 1°×1° reanal ysis data of every 6h, in terms of the synoptic principle and the dynamic diag nosis, the cold wave during 26 December 2008 has been analyzed. The resu lts are as follows: The cold wave occurred when the European ridge developed in tensely and moved eastwards, and the zonal circulation changed into the meridion al one in the middlehigh latitude in the Northern Hemisphere. The northerly wi nd in front of the ridge moved southwards. The vorticity of the transverse tr ough in the west was larger than that in the east. Both the negative variation o f the heightlocated in the southeast part in front of the trough and the posit ive variation of height behind the trough were favorable to t he revising of the transverse trough. The polar vortex and the revising transver se trough get together causing the deepening of the trough. Meanwhile, the cold air strengthened and invaded to the south. The ridge impulsed by the trough move d southeastwards and broke down gradually. Afterwards, the northerly wind change d into the northwesterly wind, which led to this coldwave process. The main re a son for the rapid air temperature decrease was the intense cold advection. The f ormation of the strong wind was correlated with not only the cold advection but also the upper disseminated momentum. There were obvious differences of the circ ulation and characteristics of the physical quantities between the rainfall and the heavy snowfall in the Shandong Peninsula. The rainfall is induced by coldw arm air converging, the heavy snowfall is caused by cold flow and difference of sea land distribution and orographic uplift. T639 model and ECMWF and Japan models , espec ially for ECMWF model, have good performances for the evolvement and adjustment of atmospheric circulation situation in the Asia middle and high latitude area.
2009, 35(12):83-87.
DOI: 10.7519/j.issn.1000-0526.2009.12.011
Abstract:
Nuclear power stations do not release greenhouse gases, such as carbon dioxi de, and thus make the contribution to reducing the carbon density of energy prod ucts. Therefore, it gets increasingly attentions of people. In view of analyzing the weather and climate environment around nuclear power station area, the study of extratropical cyclones that influence Jingyu n uclear power station area has been made. The result shows: there were 111 extrat ropical cyclones totally that influence Jingyu area from 1949 to 2007. There wer e 41 years that were influenced by the extratropical cyclones (approximately 2/3 ). The extratropical cyclones that influence Jingyu area and produce strong rain fall, mainly occurred in June, July and August, more than half of them were in J uly. Most of the extratropical cyclones that influence Jingyu area were Northeast cyc lone, which is 65% of the total; what followed behind it were Mongolian cyclone and North China cyclone; Jianghuai cyclone is the last one. Extratropical cyclon es cause severe rainfall and gale disasters, some weather disasters are extremely seri ous. Of them a case study of the extratropical cyclone was also made from synoptic analysis.
Nuclear power stations do not release greenhouse gases, such as carbon dioxi de, and thus make the contribution to reducing the carbon density of energy prod ucts. Therefore, it gets increasingly attentions of people. In view of analyzing the weather and climate environment around nuclear power station area, the study of extratropical cyclones that influence Jingyu n uclear power station area has been made. The result shows: there were 111 extrat ropical cyclones totally that influence Jingyu area from 1949 to 2007. There wer e 41 years that were influenced by the extratropical cyclones (approximately 2/3 ). The extratropical cyclones that influence Jingyu area and produce strong rain fall, mainly occurred in June, July and August, more than half of them were in J uly. Most of the extratropical cyclones that influence Jingyu area were Northeast cyc lone, which is 65% of the total; what followed behind it were Mongolian cyclone and North China cyclone; Jianghuai cyclone is the last one. Extratropical cyclon es cause severe rainfall and gale disasters, some weather disasters are extremely seri ous. Of them a case study of the extratropical cyclone was also made from synoptic analysis.
2009, 35(12):88-95.
DOI: 10.7519/j.issn.1000-0526.2009.12.012
Abstract:
According to the security class of wind turbine generator systems (WTGS), the ch aracters of tracks, intensity and wind of tropical cyclone〖JP2〗 s (TC), which impacted China coast areas, were analyzed in detail by usin g the TC data from 1961 to 2006 and selecting TC which entered the warning regio n about 3 degrees in latitude from the coastline and impacted China coast. The a nalysis showed that typhoon and severe tropical storm (STS) accounted for 59.5% of the total frequency, super typhoon and severe typhoon accounted for 21.5% of the total frequency. In Zhejiang and its southern coast the 10min average maximum wind speed of TC was over 25m·s-1,and it is less than 25m·s-1 in its northe rn coast. The region, where the 10min average maximum wind speed was over 40m·s-1, is mainly at the Guangdong coast east of the Zhujiang Estuary and southeastern coast of Hainan. The high wind of TC, which landed at Fujian and its northern coast and whose intensity was over typhoon, was usually over 25m·s-1, and the intensity of TC, which landed at the south of Fujian and caused high wind, was over severe tropical storm. The availability of TC high wind is over 80% at the middlesouthern coast of Fujian and Jiangsu coast, and the areas are mainly at the middle coast of Zhejiang, the coast at the borderline of Zhejiang and Fujian Provinces and Guangdong coast east of Zhujiang Estuary, where the TC threatens the safety of wind turbines.
According to the security class of wind turbine generator systems (WTGS), the ch aracters of tracks, intensity and wind of tropical cyclone〖JP2〗 s (TC), which impacted China coast areas, were analyzed in detail by usin g the TC data from 1961 to 2006 and selecting TC which entered the warning regio n about 3 degrees in latitude from the coastline and impacted China coast. The a nalysis showed that typhoon and severe tropical storm (STS) accounted for 59.5% of the total frequency, super typhoon and severe typhoon accounted for 21.5% of the total frequency. In Zhejiang and its southern coast the 10min average maximum wind speed of TC was over 25m·s-1,and it is less than 25m·s-1 in its northe rn coast. The region, where the 10min average maximum wind speed was over 40m·s-1, is mainly at the Guangdong coast east of the Zhujiang Estuary and southeastern coast of Hainan. The high wind of TC, which landed at Fujian and its northern coast and whose intensity was over typhoon, was usually over 25m·s-1, and the intensity of TC, which landed at the south of Fujian and caused high wind, was over severe tropical storm. The availability of TC high wind is over 80% at the middlesouthern coast of Fujian and Jiangsu coast, and the areas are mainly at the middle coast of Zhejiang, the coast at the borderline of Zhejiang and Fujian Provinces and Guangdong coast east of Zhujiang Estuary, where the TC threatens the safety of wind turbines.
2009, 35(12):96-101.
DOI: 10.7519/j.issn.1000-0526.2009.12.013
Abstract:
Based on the data of annual mean temperature at Chifeng of Inner Mongolia and su rrounding 3 me teorological stations from 1959 to 2007, a contrast analysis is made concerning the influence of the heat island effect and move of Chifeng Station on temperatu re measurements. Results show that th e Chifeng Station has been affected by heat island effect, and annual mean temp e rature in Chifeng increased about 0.7℃ by heat island effect. The heat island i nt ensity was also increasing，and its warming rate was 0.29℃／10a． After st ation moving, the heat island effect disappeared, and the i ncreasing t emperature range in Chifeng becomes smaller, thus temperature changing trend see ms incont inuous,and the remarkable jump point of the abrupt climatic change is also chang ed.
Based on the data of annual mean temperature at Chifeng of Inner Mongolia and su rrounding 3 me teorological stations from 1959 to 2007, a contrast analysis is made concerning the influence of the heat island effect and move of Chifeng Station on temperatu re measurements. Results show that th e Chifeng Station has been affected by heat island effect, and annual mean temp e rature in Chifeng increased about 0.7℃ by heat island effect. The heat island i nt ensity was also increasing，and its warming rate was 0.29℃／10a． After st ation moving, the heat island effect disappeared, and the i ncreasing t emperature range in Chifeng becomes smaller, thus temperature changing trend see ms incont inuous,and the remarkable jump point of the abrupt climatic change is also chang ed.
2009, 35(12):102-108.
DOI: 10.7519/j.issn.1000-0526.2009.12.014
Abstract:
The relationships among the air temperatures of litchi orchard, cano py and observation station in four weather types, i.e. the sunny, cloudy, rainy, and cloudy to sunny cases were analyzed based on field data in winter, 〖JP2〗2007/2008 and 2008/2009. The results showed that the canopy temperature changes between daytime and nighttime we re the largest in the sunny case, in the cloudy to sunny case the temperature changes between daytime and nighttime were the second, however, in the cloudy or rainy case the temperature changes between daytime and nighttime were smoot hly. In the same time, the orchard and observation station temperature changes between daytime and nighttime were closely related with weather types. Th e linear or curvilinear regression relationships of observation station and canopy temperatures w ere set up for da ytime and nighttime and the whole day based on different weather types . The res ults showed that the relationship models for cloudy and rainy cases and advectio n cold chilling were better than sunny and cloudy to sunny cases. In all models, the models of night time were the best. The results of this research show that it is feasible to monitor litch i cold chilling and frozen injury with air temperature of observation station.
The relationships among the air temperatures of litchi orchard, cano py and observation station in four weather types, i.e. the sunny, cloudy, rainy, and cloudy to sunny cases were analyzed based on field data in winter, 〖JP2〗2007/2008 and 2008/2009. The results showed that the canopy temperature changes between daytime and nighttime we re the largest in the sunny case, in the cloudy to sunny case the temperature changes between daytime and nighttime were the second, however, in the cloudy or rainy case the temperature changes between daytime and nighttime were smoot hly. In the same time, the orchard and observation station temperature changes between daytime and nighttime were closely related with weather types. Th e linear or curvilinear regression relationships of observation station and canopy temperatures w ere set up for da ytime and nighttime and the whole day based on different weather types . The res ults showed that the relationship models for cloudy and rainy cases and advectio n cold chilling were better than sunny and cloudy to sunny cases. In all models, the models of night time were the best. The results of this research show that it is feasible to monitor litch i cold chilling and frozen injury with air temperature of observation station.
2009, 35(12):109-117.
DOI: 10.7519/j.issn.1000-0526.2009.12.015
Abstract:
Changes of accumulated temperature and days steadily above 0℃ and 10℃ in Liaoning Province from 1951 to 2007 are analyzed in this paper. The results indicate as follows: (1) The accumulated temperature steadily above 0℃ and 10℃ signifi cantly increases in the recent 57 years. (2) The accumulated temperature undergoes different changes for different time periods in the recent 57 years, with a weak increase for the first or second 30 years, and a strong increase for the last 30 years. The d ays steadily above 0℃ and 10℃ also obviously increase in the period analyzed, with the last 30 years seeing a much more evident rising than the previous per iods. (3) The increases in the accumulated temperature and days steadily above 0 ℃ and 10℃ are generally larger in the middle and the coastal areas, and they a re also larger at the large cities than at the small cities, implying that urbanizatio ns might have some influences on the surface temperature and accumulated temperatu re changes. However, the regional background climate warming would be also impor tant for the observed changes in the accumulated temperature and days steadily a bove 0℃ and 10℃.
Changes of accumulated temperature and days steadily above 0℃ and 10℃ in Liaoning Province from 1951 to 2007 are analyzed in this paper. The results indicate as follows: (1) The accumulated temperature steadily above 0℃ and 10℃ signifi cantly increases in the recent 57 years. (2) The accumulated temperature undergoes different changes for different time periods in the recent 57 years, with a weak increase for the first or second 30 years, and a strong increase for the last 30 years. The d ays steadily above 0℃ and 10℃ also obviously increase in the period analyzed, with the last 30 years seeing a much more evident rising than the previous per iods. (3) The increases in the accumulated temperature and days steadily above 0 ℃ and 10℃ are generally larger in the middle and the coastal areas, and they a re also larger at the large cities than at the small cities, implying that urbanizatio ns might have some influences on the surface temperature and accumulated temperatu re changes. However, the regional background climate warming would be also impor tant for the observed changes in the accumulated temperature and days steadily a bove 0℃ and 10℃.
16 Climatic Characteristics of Thunderstorms in Changzhou
Within 56 Years and Radar Echo Characters
2009, 35(12):118-125.
DOI: 10.7519/j.issn.1000-0526.2009.12.016
Abstract:
By using the long series observational data of thunderstorms in Changzhou from 1952 to 2007 and Doppler radar data, the variation, periodic char acteristics and echo characters of thunderstorms are studied by means of mathema t ical statistics and the wavelet analysis. The results show that the interdec adal thunder storm variability is great, and the annual number of thunderstorm day has a decr easing tr end. The interannual variation in thunderstorm day number is comparatively larg e with the maxi mum being 5.9 times the minimum. The obvious seasonal variation of thunderstorms can also be detected, and the period of April to Sep tember is more frequent months for th understorms and their occurrence in July and August is the most, and over 66.8% thunder storms occur in summer season. From the diurnal distribution, the highest number i s in the evening, followed by the afternoon, at least in the morning. The result s from wav elet analysis show that the annual number of thunderstorm days in Chan gzh ou has a period of about 12 years within nearly 56 years and there is a perio d of about 7 y ears from 1952 to 2004.In addition, there is still three to four years of small cycle charact eristics from 1968 to 2007. It is found that the radar basic reflectivity of thu nderstor ms in Changzhou is from 30 to 65dBz and the echo tophigh is between 6 to 17km and the thunderstorm radar echoes are in five major shifts: the southwest to nor the ast, the southeast to northwest, the northwest to southeast, the rotation, and the local gen eration.The strong wind and hail storm in Changzhou are analyzed using statistic al analysis methods. It is found that the thunderstorm winds occurring in July ran k on top and the hail occurs the most in May and July.
By using the long series observational data of thunderstorms in Changzhou from 1952 to 2007 and Doppler radar data, the variation, periodic char acteristics and echo characters of thunderstorms are studied by means of mathema t ical statistics and the wavelet analysis. The results show that the interdec adal thunder storm variability is great, and the annual number of thunderstorm day has a decr easing tr end. The interannual variation in thunderstorm day number is comparatively larg e with the maxi mum being 5.9 times the minimum. The obvious seasonal variation of thunderstorms can also be detected, and the period of April to Sep tember is more frequent months for th understorms and their occurrence in July and August is the most, and over 66.8% thunder storms occur in summer season. From the diurnal distribution, the highest number i s in the evening, followed by the afternoon, at least in the morning. The result s from wav elet analysis show that the annual number of thunderstorm days in Chan gzh ou has a period of about 12 years within nearly 56 years and there is a perio d of about 7 y ears from 1952 to 2004.In addition, there is still three to four years of small cycle charact eristics from 1968 to 2007. It is found that the radar basic reflectivity of thu nderstor ms in Changzhou is from 30 to 65dBz and the echo tophigh is between 6 to 17km and the thunderstorm radar echoes are in five major shifts: the southwest to nor the ast, the southeast to northwest, the northwest to southeast, the rotation, and the local gen eration.The strong wind and hail storm in Changzhou are analyzed using statistic al analysis methods. It is found that the thunderstorm winds occurring in July ran k on top and the hail occurs the most in May and July.
2009, 35(12):126-132.
DOI: 10.7519/j.issn.1000-0526.2009.12.017
Abstract:
With the rapid development of highway communication, the influences of th e dense fog on the transportation system are becoming more and more serious. The dense fog often leads to the traffic accident, and gives rise to tremendous los s to the lives and the property of people，thus it is very harmful. By using the meteorological data from 1957 to 2006, the characteristics of the temporal and spatial distributions on the dense fog in its inland and the c oastal area of Qinhuangdao City are analyzed, and by means of the historic synoptic c harts from 1981 to 2000, the synoptic patterns of the dense fog are also obtained. The major meteorological elements influencing the dense fog are selected fr om many factors, and thereby the equation of the MOS forecast about the dense fo g is set up. That will offer a strong support to the forecast of the dense fog, the issuance of early warning signal and its annulment. Therefrom, the purpose o f monitoring and forecasting the dense fog will be achieved.
With the rapid development of highway communication, the influences of th e dense fog on the transportation system are becoming more and more serious. The dense fog often leads to the traffic accident, and gives rise to tremendous los s to the lives and the property of people，thus it is very harmful. By using the meteorological data from 1957 to 2006, the characteristics of the temporal and spatial distributions on the dense fog in its inland and the c oastal area of Qinhuangdao City are analyzed, and by means of the historic synoptic c harts from 1981 to 2000, the synoptic patterns of the dense fog are also obtained. The major meteorological elements influencing the dense fog are selected fr om many factors, and thereby the equation of the MOS forecast about the dense fo g is set up. That will offer a strong support to the forecast of the dense fog, the issuance of early warning signal and its annulment. Therefrom, the purpose o f monitoring and forecasting the dense fog will be achieved.
2009, 35(12):133-138.
DOI: 10.7519/j.issn.1000-0526.2009.12.018
Abstract:
The distribution of high performance computing resources is inhomogeneous ge ographically. As a result, some local meteorological bureaus fail to conduct loc al meteorological forecast operations or researches. Thereby， funded by “Natio n al Science and Technology Infrastructure Plan”, the resource integration and ma nagement are done by China Meteorological Administration. It hoped to realiz e the sharing of resources in CMA and increase the effectiveness of resources' utilization. As a node, Liaoning Meteorological Bureau joined the national meteorological network computing application system. It is an urgent task for Liaoning Meteorologi cal Bureau to upgrade system management from homogeneous systems to global system management across multiple heterogeneous systems.Regarding the requirements of resource integration, sharing and management by Liaoning meteorological departme nt, a design scheme of Liaoning meteorological computing application system is p roposed. The scheme utilizes computational grid as the platform building technol ogy. The design scheme includes user interface, grid management, high performanc e computer local management. Regarding the integration requirement of heterogene ous computing resources, a solution is proposed consisting of globally coherent, cen tralized user management and metascheduler of job management. To build a unifo r m grid application support environment, schemes are proposed for typical meteoro logical grid applications and application interfaces respectively. In conclusion, an implementation of Liaoning meteorological network computin g application system is proposed based on the requirements of meteorological ser vices，with which immediate and efficient supports are supplied.
The distribution of high performance computing resources is inhomogeneous ge ographically. As a result, some local meteorological bureaus fail to conduct loc al meteorological forecast operations or researches. Thereby， funded by “Natio n al Science and Technology Infrastructure Plan”, the resource integration and ma nagement are done by China Meteorological Administration. It hoped to realiz e the sharing of resources in CMA and increase the effectiveness of resources' utilization. As a node, Liaoning Meteorological Bureau joined the national meteorological network computing application system. It is an urgent task for Liaoning Meteorologi cal Bureau to upgrade system management from homogeneous systems to global system management across multiple heterogeneous systems.Regarding the requirements of resource integration, sharing and management by Liaoning meteorological departme nt, a design scheme of Liaoning meteorological computing application system is p roposed. The scheme utilizes computational grid as the platform building technol ogy. The design scheme includes user interface, grid management, high performanc e computer local management. Regarding the integration requirement of heterogene ous computing resources, a solution is proposed consisting of globally coherent, cen tralized user management and metascheduler of job management. To build a unifo r m grid application support environment, schemes are proposed for typical meteoro logical grid applications and application interfaces respectively. In conclusion, an implementation of Liaoning meteorological network computin g application system is proposed based on the requirements of meteorological ser vices，with which immediate and efficient supports are supplied.
2009, 35(12):139-143.
DOI: 10.7519/j.issn.1000-0526.2009.12.019
Abstract:
A forecast method of extended range is introduced. By usi ng the global model of the grid prediction of 500hPa height fields in the Europe an Ce nter for Medium Range Weather Forecasts（ECMWF）, the correlations between the predicted value and NCEP reanalysis data of 500hPa height fields at the same time in the past years are obtained. Among these correlations，three l argest correlat〖JP2〗 ion coefficients are picked out. Meanwhile, by using daily observed precipitatio n d ata in the past years, daily probabilities of sunny, light rain, moderate rain, heavy rain and rainstorm are gained which are treated as background probabilitie s. The best related year is computed with control of the background probabilitie s. Taking observed precipitation in that year as the predicted one, so that the prediction for the extended range (10-20 days) will be made.Operational experimentation and verification show that the method is effe ctive.
A forecast method of extended range is introduced. By usi ng the global model of the grid prediction of 500hPa height fields in the Europe an Ce nter for Medium Range Weather Forecasts（ECMWF）, the correlations between the predicted value and NCEP reanalysis data of 500hPa height fields at the same time in the past years are obtained. Among these correlations，three l argest correlat〖JP2〗 ion coefficients are picked out. Meanwhile, by using daily observed precipitatio n d ata in the past years, daily probabilities of sunny, light rain, moderate rain, heavy rain and rainstorm are gained which are treated as background probabilitie s. The best related year is computed with control of the background probabilitie s. Taking observed precipitation in that year as the predicted one, so that the prediction for the extended range (10-20 days) will be made.Operational experimentation and verification show that the method is effe ctive.
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ISSN:1000-0526 CN:11-2282/P