ISSN 1000-0526
CN 11-2282/P
CN 11-2282/P
Volume 37,Issue 9,2011 Table of Contents
2011, 37(9):1049-1059.
DOI: 10.7519/j.issn.1000-0526.2011.9.001
Abstract:
The CMA T213 global ensemble prediction system using BGM initial perturbation scheme has not considered model perturbation thus lags behind the ensemble forecasting system of international advanced technical centers. This paper referring to the ECMWF model perturbation method, designs a T213 global ensemble prediction system stochastic physics perturbation method, and conducts ensemble prediction tests in 20-31 July 2008. The results show that, the T213 global ensemble prediction system is very sensitive to stochastic physics perturbation. This is because after physics perturbed, predictor variables change significantly, and the changes expand rapidly with the integration time of growth. In the horizontal direction, the middle and high latitudes are more sensitive than the equatorial regions. In the vertical direction, the variables characterizing the largescale movements, such as geopotential height, temperature, and wind speed are very sensitive from low to upper levels, and the most sensitive is at 300 hPa, in the middle and high latitudes of north and south hemispheres; while vertical velocity, divergence and other physical variables in the equatorial region are also very sensitive. After the multiple initial condition ensemble added to the stochastic physics perturbations, the spread and RMSE of ensemble mean are improved slightly in the late term of integration, while the improvement of the precipitation forecast is significant, which indicates the prospect of operation to the stochastic physics perturbation is good. The next step will be more test assessments, and the operations of the stochastic physics perturbation are as early as possible to shorten the distance between China and the international advanced technology in the ensemble.
The CMA T213 global ensemble prediction system using BGM initial perturbation scheme has not considered model perturbation thus lags behind the ensemble forecasting system of international advanced technical centers. This paper referring to the ECMWF model perturbation method, designs a T213 global ensemble prediction system stochastic physics perturbation method, and conducts ensemble prediction tests in 20-31 July 2008. The results show that, the T213 global ensemble prediction system is very sensitive to stochastic physics perturbation. This is because after physics perturbed, predictor variables change significantly, and the changes expand rapidly with the integration time of growth. In the horizontal direction, the middle and high latitudes are more sensitive than the equatorial regions. In the vertical direction, the variables characterizing the largescale movements, such as geopotential height, temperature, and wind speed are very sensitive from low to upper levels, and the most sensitive is at 300 hPa, in the middle and high latitudes of north and south hemispheres; while vertical velocity, divergence and other physical variables in the equatorial region are also very sensitive. After the multiple initial condition ensemble added to the stochastic physics perturbations, the spread and RMSE of ensemble mean are improved slightly in the late term of integration, while the improvement of the precipitation forecast is significant, which indicates the prospect of operation to the stochastic physics perturbation is good. The next step will be more test assessments, and the operations of the stochastic physics perturbation are as early as possible to shorten the distance between China and the international advanced technology in the ensemble.
2011, 37(9):1060-1069.
DOI: 10.7519/j.issn.1000-0526.2011.9.002
Abstract:
The heavy rainfall which occurred from 19 to 20 June 2010, was simulated by using WRF model coupled with four land surface processes. The sensitivity of land surface process to the intensity and range of heavy rainfall was analyzed. The results show that the rain bands simulated by four land surface processes coupled with WRF are accordance with the observations, as well as the simulated strong precipitation centers are also in phase with the observations. The lack of land surface scheme leads to the obvious shift of intensity, range and position of heavy rainfall. In addition, the heavy precipitation is associated with areas of large runoff and even larger soil moisture increment. Due to the saturation soil water content, the excess precipitation was assigned to the surface runoff. This is the important reason to the rapid rise of water level. Under wet soil moisture conditions, the enhanced flux of heat from the surface into the boundary layer air favored a relatively large magnitude of PBL height and latent heat flux. This is the key which caused the abnormal precipitation increase of this heavy rainfall event.
The heavy rainfall which occurred from 19 to 20 June 2010, was simulated by using WRF model coupled with four land surface processes. The sensitivity of land surface process to the intensity and range of heavy rainfall was analyzed. The results show that the rain bands simulated by four land surface processes coupled with WRF are accordance with the observations, as well as the simulated strong precipitation centers are also in phase with the observations. The lack of land surface scheme leads to the obvious shift of intensity, range and position of heavy rainfall. In addition, the heavy precipitation is associated with areas of large runoff and even larger soil moisture increment. Due to the saturation soil water content, the excess precipitation was assigned to the surface runoff. This is the important reason to the rapid rise of water level. Under wet soil moisture conditions, the enhanced flux of heat from the surface into the boundary layer air favored a relatively large magnitude of PBL height and latent heat flux. This is the key which caused the abnormal precipitation increase of this heavy rainfall event.
2011, 37(9):1070-1080.
DOI: 10.7519/j.issn.1000-0526.2011.9.003
Abstract:
By using the GRAPES artificial precipitation model, a precipitation process on July 4, 2008 in Chongqing is simulated. and the characteristics of vapor distribution, cloud microstructure, microphysical conversion and artificial potential are analyzed, the results show that: in this precipitation process, the water vapor is extremely rich in Chongqing, and the vapor distribution is corresponding to the topographic distribution. Meanwhile, the lowlevel water vapor transport is large, the whole layer of water vapor flux is relatively high; with a moisture convergence, the cloud liquid water has a great impact on ground rainfall. Southwest air flow and terrain together provide favorable conditions for the formation of liquid water in Chongqing. There is a large amount of water vapor accumulated in the windward slope of northeastern mountain area, and easy to form a wealth of liquid water. In this precipitation process， a plenty of water vapor converted into cloud water in northeast of Chongqing， then it is rich in supercool liquid water， less in ice number， low in precipitation efficiency， and the vapor vertical flux is large at 0℃ layer， therefore it has greater potential for precipitation enhancement.
By using the GRAPES artificial precipitation model, a precipitation process on July 4, 2008 in Chongqing is simulated. and the characteristics of vapor distribution, cloud microstructure, microphysical conversion and artificial potential are analyzed, the results show that: in this precipitation process, the water vapor is extremely rich in Chongqing, and the vapor distribution is corresponding to the topographic distribution. Meanwhile, the lowlevel water vapor transport is large, the whole layer of water vapor flux is relatively high; with a moisture convergence, the cloud liquid water has a great impact on ground rainfall. Southwest air flow and terrain together provide favorable conditions for the formation of liquid water in Chongqing. There is a large amount of water vapor accumulated in the windward slope of northeastern mountain area, and easy to form a wealth of liquid water. In this precipitation process， a plenty of water vapor converted into cloud water in northeast of Chongqing， then it is rich in supercool liquid water， less in ice number， low in precipitation efficiency， and the vapor vertical flux is large at 0℃ layer， therefore it has greater potential for precipitation enhancement.
2011, 37(9):1081-1090.
DOI: 10.7519/j.issn.1000-0526.2011.9.004
Abstract:
The 6hourly precipitation data from 673 rain gauge records are used to verify the accuracy of Tropical Rainfall Measuring Mission (TRMM) 3B42 products from June to August (JJA) during 2004-2008 in China. The results show that the satellite products are similar to rain gauge data in revealing the spatial patterns of JJA mean precipitation amount and precipitation frequency during 2004-2008. The pattern correlation coefficients of daily rainfall amount and rainfall frequency are 0.79 and 0.84, respectively. The satellite product overestimates rainfall frequency. Based on the spatial distributions of correlation coefficients of daily rainfall amount, the correlation coefficients between TRMM products and rain gauge data range from 0.6 to 0.9 in eastern China. According to the spatial patterns of mean absolute error (MAE) of daily and 6hourly precipitation amount, the MAE in South China is the largest, followed by the Yangtze River Basin. From diurnal cycle of the 6hourly total precipitation amount over eight subregions, the TRMM product has a good resemblance with rain gauge observations except the big difference in the afternoon (1400-2000 LST) in South China. Based on the spatial patterns of mean relative error (MRE) of different rainfall amount, the TRMM product behaves as follows: light rains is overestimated nearly in whole country; moderate rain is larger in some regions of eastern China; the MREs of heavy rain and torrential rain are less than 1 in most areas of China. Mean rates of the missing retrieval and the vacancy retrieval are 10% and 14% respectively in China.
The 6hourly precipitation data from 673 rain gauge records are used to verify the accuracy of Tropical Rainfall Measuring Mission (TRMM) 3B42 products from June to August (JJA) during 2004-2008 in China. The results show that the satellite products are similar to rain gauge data in revealing the spatial patterns of JJA mean precipitation amount and precipitation frequency during 2004-2008. The pattern correlation coefficients of daily rainfall amount and rainfall frequency are 0.79 and 0.84, respectively. The satellite product overestimates rainfall frequency. Based on the spatial distributions of correlation coefficients of daily rainfall amount, the correlation coefficients between TRMM products and rain gauge data range from 0.6 to 0.9 in eastern China. According to the spatial patterns of mean absolute error (MAE) of daily and 6hourly precipitation amount, the MAE in South China is the largest, followed by the Yangtze River Basin. From diurnal cycle of the 6hourly total precipitation amount over eight subregions, the TRMM product has a good resemblance with rain gauge observations except the big difference in the afternoon (1400-2000 LST) in South China. Based on the spatial patterns of mean relative error (MRE) of different rainfall amount, the TRMM product behaves as follows: light rains is overestimated nearly in whole country; moderate rain is larger in some regions of eastern China; the MREs of heavy rain and torrential rain are less than 1 in most areas of China. Mean rates of the missing retrieval and the vacancy retrieval are 10% and 14% respectively in China.
2011, 37(9):1091-1099.
DOI: 10.7519/j.issn.1000-0526.2011.9.005
Abstract:
Using FNL（NCEP/NCAR）reanalysis data (1°×1°) and observations, some characteristics of six recent tropical cyclones causing heavy rainfall in Qingdao from 2001 to 2008 are analyzed from their tracks, structures, intensities and environmental flow effects etc. Then the comparative analysis of characteristics between tropical cyclones (TCs) causing heavy rainfall and those not in Qingdao is made by using composite analysis method. Results show that heavy rainfall will occur in Qingdao when a TC makes landfall over Fujian or Zhejiang Province in China and continues to move northward over 30°N. And when a TC moves into the sea and makes landfall over Shandong Peninsula again, the more intense rate and wider area of heavy rainfall will occur if its landing location is closer to Qingdao. When a TC impacts Qingdao, although it is in decline stage, it still keeps a clear warm core at upper levels and maintains its intensity for a period of time. And if a TC moves along the steering flow at edge of the massive subtropical high and links with a cold trough aloft, it will cause regional heavy rainfall over Qingdao.
Using FNL（NCEP/NCAR）reanalysis data (1°×1°) and observations, some characteristics of six recent tropical cyclones causing heavy rainfall in Qingdao from 2001 to 2008 are analyzed from their tracks, structures, intensities and environmental flow effects etc. Then the comparative analysis of characteristics between tropical cyclones (TCs) causing heavy rainfall and those not in Qingdao is made by using composite analysis method. Results show that heavy rainfall will occur in Qingdao when a TC makes landfall over Fujian or Zhejiang Province in China and continues to move northward over 30°N. And when a TC moves into the sea and makes landfall over Shandong Peninsula again, the more intense rate and wider area of heavy rainfall will occur if its landing location is closer to Qingdao. When a TC impacts Qingdao, although it is in decline stage, it still keeps a clear warm core at upper levels and maintains its intensity for a period of time. And if a TC moves along the steering flow at edge of the massive subtropical high and links with a cold trough aloft, it will cause regional heavy rainfall over Qingdao.
2011, 37(9):1100-1107.
DOI: 10.7519/j.issn.1000-0526.2011.9.006
Abstract:
Using the data obtained by conventional observations, ground densified automatic weather stations, Doppler radar observations and mesoscale TJWRF model， we analyze the heavy rain occurring on 6 July 2009 at Ninghe District of Tianjin and highlight the trigger mechanism of coastal local storm caused by sea breeze front of the Bohai Gulf. The results show that the heavy rain occurred in the favorable weather conditions, and there were local instability and adequate vapor conditions. Sea breeze front itself has a convergent uplift area where weak convection exists; when sea breeze front moves to the unstable and adequate vapor areas, it will strengthen the convergence positive movement of convergent uplift area and lead to the new storm development. The meeting of the sea breeze front and thunderstorm will play a strengthened role in its development. By analyzing the data obtained by mesoscale WRF model, we can see that at the warm and dry ground in front area near the north end of the wet air interchange, the intersection of the two convergence lines is easy to stimulate strong thunderstorms, and thunderstorm accrues at the intersection of the north of the subaerial warm and dry front zone and humid air. Sea breeze front plays an important role in the development of the thunderstorm.
Using the data obtained by conventional observations, ground densified automatic weather stations, Doppler radar observations and mesoscale TJWRF model， we analyze the heavy rain occurring on 6 July 2009 at Ninghe District of Tianjin and highlight the trigger mechanism of coastal local storm caused by sea breeze front of the Bohai Gulf. The results show that the heavy rain occurred in the favorable weather conditions, and there were local instability and adequate vapor conditions. Sea breeze front itself has a convergent uplift area where weak convection exists; when sea breeze front moves to the unstable and adequate vapor areas, it will strengthen the convergence positive movement of convergent uplift area and lead to the new storm development. The meeting of the sea breeze front and thunderstorm will play a strengthened role in its development. By analyzing the data obtained by mesoscale WRF model, we can see that at the warm and dry ground in front area near the north end of the wet air interchange, the intersection of the two convergence lines is easy to stimulate strong thunderstorms, and thunderstorm accrues at the intersection of the north of the subaerial warm and dry front zone and humid air. Sea breeze front plays an important role in the development of the thunderstorm.
Ma Zhong Yuan
,
Ye Xiaofeng
,
Zhang Ying
,
Xu Aihua
,
Ma Xiaolin
,
He Zhiming
,
Xiao An
,
Chen Yunhui
2011, 37(9):1108-1117.
DOI: 10.7519/j.issn.1000-0526.2011.9.007
Abstract:
Hazard wind weathers in Jiangxi are discussed with conventional data, disaster information and radar data, it is found that there are three major weather types of disastrous winds, i.e. (1) thunderstorm gale weather accompanied by the radar echo systems with the echo band of squall line and super cell etc., at the same time, also accompanied by strong lightning, severe precipitation, hailstone, tornado and other hazard weathers; (2) hybridgale weather, accompanied by thunderstorm echo band of cold front and cold air gale, presents the characteristics of thunderstorm gale and cold air gale activities; (3) disastrous wind weather without rainfall, caused by the joint action of downdraft of thunderstorm triggering, downpropagation of aloft kinetic energy as well as pressure gradient wind, and it is not accompanied by rainfall, lightning and other weather phenomenon.
Hazard wind weathers in Jiangxi are discussed with conventional data, disaster information and radar data, it is found that there are three major weather types of disastrous winds, i.e. (1) thunderstorm gale weather accompanied by the radar echo systems with the echo band of squall line and super cell etc., at the same time, also accompanied by strong lightning, severe precipitation, hailstone, tornado and other hazard weathers; (2) hybridgale weather, accompanied by thunderstorm echo band of cold front and cold air gale, presents the characteristics of thunderstorm gale and cold air gale activities; (3) disastrous wind weather without rainfall, caused by the joint action of downdraft of thunderstorm triggering, downpropagation of aloft kinetic energy as well as pressure gradient wind, and it is not accompanied by rainfall, lightning and other weather phenomenon.
2011, 37(9):1118-1125.
DOI: 10.7519/j.issn.1000-0526.2011.9.008
Abstract:
By using the thunderstorm data of thirty years during 1980 to 2009, this paper has analyzed the time distribution characteristics and variation regularity of the strong thunderstorm in Hongze Lake region, and classified the synoptic situation of strong thunderstorm days in terms of weather maps during 2005 to 2009. It is found that the average annual strong thunderstorm day is 8.0 d, the main meteorological disasters accompanied by strong thunderstorm are strong wind and heavy rainfall; it is more likely to happen in June to August and 〖JP2〗most frequently at 4 am to 6 am and 14 pm to 16 pm of a day, which often sustained within 2 hours. The second order moving average (decadal change) goes up at first, and then falls down. The strong thunderstorm forms in four synoptic systems: trough cold front, northern cold vortex, lowlevel shear(trough) line, and subtropical high; at the same time the southwest jet exists in both lowlevel and highlevel atmosphere, and the Hongze Lake region is in a wet tongue where T-Td of 850 hPa is no more than -3℃. The main echo features of the strong thunderstorm are as follows: there is a sharp vertical shear before the echoes, and the remaining VIL value at the 35 kg·m-2 implicates the appearance of heavy rainfalls; before strong winds, VIL value often declines evidently. And during the rainstorm, its negative lightning concentration region is in good correspondance with the strong radar echoes above 40 dBz.
By using the thunderstorm data of thirty years during 1980 to 2009, this paper has analyzed the time distribution characteristics and variation regularity of the strong thunderstorm in Hongze Lake region, and classified the synoptic situation of strong thunderstorm days in terms of weather maps during 2005 to 2009. It is found that the average annual strong thunderstorm day is 8.0 d, the main meteorological disasters accompanied by strong thunderstorm are strong wind and heavy rainfall; it is more likely to happen in June to August and 〖JP2〗most frequently at 4 am to 6 am and 14 pm to 16 pm of a day, which often sustained within 2 hours. The second order moving average (decadal change) goes up at first, and then falls down. The strong thunderstorm forms in four synoptic systems: trough cold front, northern cold vortex, lowlevel shear(trough) line, and subtropical high; at the same time the southwest jet exists in both lowlevel and highlevel atmosphere, and the Hongze Lake region is in a wet tongue where T-Td of 850 hPa is no more than -3℃. The main echo features of the strong thunderstorm are as follows: there is a sharp vertical shear before the echoes, and the remaining VIL value at the 35 kg·m-2 implicates the appearance of heavy rainfalls; before strong winds, VIL value often declines evidently. And during the rainstorm, its negative lightning concentration region is in good correspondance with the strong radar echoes above 40 dBz.
Ma Xincheng
,
Wu Hongyi
,
Ji Lei
,
Zhang Qiang
,
Huang Mengyu
,
Li Hongyu
,
Yang Daoxia
,
He Hui
,
Zhang Lei
,
Li Ruijie
,
Liu Liwei
,
Han Guang
2011, 37(9):1126-1133.
DOI: 10.7519/j.issn.1000-0526.2011.9.009
Abstract:
In this study, aerosol （0.1-3.0 μm）vertical distributions of 17 insitu aircraft measurements during 2005 and 2006 springs are analyzed. The 17 flights are carefully selected to exclude dust events, and the analyses are focused on the vertical distributions of aerosol particles associated with anthropogenic activities. The results show that the vertical distributions of aerosol particles are strongly affected by weather and meteorological conditions, and 3 different types of aerosol vertical distributions corresponding to different weather systems are defined in this study. The measurement with a flat vertical gradient and low surface aerosol concentrations is defined as type1; a gradually decrease of aerosols with altitudes and modest surface aerosol concentrations is defined as type2; a sharp vertical gradient (aerosols being strongly depressed in the PBL) with high surface aerosol concentrations is defined as type3. The weather conditions corresponding to the 3 different aerosol types are high pressure, between two high pressures, and low pressure systems (frontal inversions), respectively. The vertical mixing and horizontal transport for the 3 different vertical distributions are analyzed. Under the type1 condition, the vertical mixing and horizontal transport were rapid, leading to a strong dilution of aerosols in both vertical and horizontal directions. As a result, the aerosol concentrations in PBL (planetary boundary layer) were very low, and the vertical distribution was flat. Under the type2 condition, the vertical mixing was strong and there was no strong barrier at the PBL height. The horizontal transport (wind flux) was modest. As a result, the aerosol concentrations were gradually reduced with altitude, with modest surface aerosol concentrations. Under the type3 condition, there was a cold front near the region. As a result, a frontal inversion associated with weak vertical mixing appeared at the top of the inversion layer, forming a very strong barrier to prevent aerosol particles being exchanged from the PBL height to the free troposphere. Therefore, the aerosol particles were strongly depressed in the PBL height, producing high surface aerosol concentrations.
In this study, aerosol （0.1-3.0 μm）vertical distributions of 17 insitu aircraft measurements during 2005 and 2006 springs are analyzed. The 17 flights are carefully selected to exclude dust events, and the analyses are focused on the vertical distributions of aerosol particles associated with anthropogenic activities. The results show that the vertical distributions of aerosol particles are strongly affected by weather and meteorological conditions, and 3 different types of aerosol vertical distributions corresponding to different weather systems are defined in this study. The measurement with a flat vertical gradient and low surface aerosol concentrations is defined as type1; a gradually decrease of aerosols with altitudes and modest surface aerosol concentrations is defined as type2; a sharp vertical gradient (aerosols being strongly depressed in the PBL) with high surface aerosol concentrations is defined as type3. The weather conditions corresponding to the 3 different aerosol types are high pressure, between two high pressures, and low pressure systems (frontal inversions), respectively. The vertical mixing and horizontal transport for the 3 different vertical distributions are analyzed. Under the type1 condition, the vertical mixing and horizontal transport were rapid, leading to a strong dilution of aerosols in both vertical and horizontal directions. As a result, the aerosol concentrations in PBL (planetary boundary layer) were very low, and the vertical distribution was flat. Under the type2 condition, the vertical mixing was strong and there was no strong barrier at the PBL height. The horizontal transport (wind flux) was modest. As a result, the aerosol concentrations were gradually reduced with altitude, with modest surface aerosol concentrations. Under the type3 condition, there was a cold front near the region. As a result, a frontal inversion associated with weak vertical mixing appeared at the top of the inversion layer, forming a very strong barrier to prevent aerosol particles being exchanged from the PBL height to the free troposphere. Therefore, the aerosol particles were strongly depressed in the PBL height, producing high surface aerosol concentrations.
2011, 37(9):1134-1139.
DOI: 10.7519/j.issn.1000-0526.2011.9.010
Abstract:
Using the monthly mean reanalysis data of the NCEP/NCAR, and the data of monthly mean SST by NOAA during 1961 to 2008, and the precipitation in spring in Chongqing from 1961 to 2008, the relationship between the spring rainfall in Chongqing and the early autumn SST is analyzed. The result shows that a close negative/positive correlation exists between the spring rainfall in Chongqing and the early autumn SST in the neighborhood of the North Pacific drift (20°-40°N，165°E-140°W)/Alaska current (40°-60°N，165°E-140°W), respectively. When the early autumn SST of the subtropical North Pacific Ocean is anomalously high, and that of middlehigh latitudes is anomalously low, then the spring rainfall in Chongqing is more. On the other hand, when the early autumn SST of the subtropical North Pacific Ocean is anomalously low, 〖JP2〗and that of middlehigh latitudes is anomalously high, then the spring rainfall in Chongqing is less. A discriminate index for diagnosing and forecasting the spring rainfall is defined according to the correlation distribution characteristics. This index stands for the opposed anomalous SST conditions of the south and north areas in the North Pacific Ocean. It has important synoptic climatological significance, and can diagnose and forecast the spring rainfall in Chongqing. The index leads to the anomalies of eigenvalues of spring 500 hPa height all through, which makes the spring rainfall in Chongqing anomalous.
Using the monthly mean reanalysis data of the NCEP/NCAR, and the data of monthly mean SST by NOAA during 1961 to 2008, and the precipitation in spring in Chongqing from 1961 to 2008, the relationship between the spring rainfall in Chongqing and the early autumn SST is analyzed. The result shows that a close negative/positive correlation exists between the spring rainfall in Chongqing and the early autumn SST in the neighborhood of the North Pacific drift (20°-40°N，165°E-140°W)/Alaska current (40°-60°N，165°E-140°W), respectively. When the early autumn SST of the subtropical North Pacific Ocean is anomalously high, and that of middlehigh latitudes is anomalously low, then the spring rainfall in Chongqing is more. On the other hand, when the early autumn SST of the subtropical North Pacific Ocean is anomalously low, 〖JP2〗and that of middlehigh latitudes is anomalously high, then the spring rainfall in Chongqing is less. A discriminate index for diagnosing and forecasting the spring rainfall is defined according to the correlation distribution characteristics. This index stands for the opposed anomalous SST conditions of the south and north areas in the North Pacific Ocean. It has important synoptic climatological significance, and can diagnose and forecast the spring rainfall in Chongqing. The index leads to the anomalies of eigenvalues of spring 500 hPa height all through, which makes the spring rainfall in Chongqing anomalous.
2011, 37(9):1140-1144.
DOI: 10.7519/j.issn.1000-0526.2011.9.011
Abstract:
In order to provide the technological basis for the agrometeorological forecast of single late rice stripe disease, the data of 95 samples of transplanting rice and direct seeding rice in 10 counties in 2007-2008 and meteorological materials in the same period and counties were analyzed using the applied mathematical statistics method. The result showed that under the condition of rice stripe virus （RSV), the primary factor of affecting the occurring of single late rice stripe disease was rice variety, and the partial correlation coefficient between resistant capability and diseased plant rate was -0.622 (P<0.01). The secondary factor was average relative humidity from seeded or transplanted to seven leaf age, and the partial correlation coefficient with which and diseased plant rate was -0.293 (P<0.01). The affecting from sowed or transplanted date of rice to single late rice stripe disease was actually through average relative humidity from seeded or transplanted to seven leaf age to the breaking out of single late rice stripe disease. Partial correlation coefficients between sowingplanting period of rice and diseased plant rate, average relative humidity from seeded or transplanted to seven leaf age were -0.036 and 0.309 (P<0.01), separately. Therefore, in the operational forecast, the rice variety and relative humidity from seeding or transplanting to seven leaf age should be focused and considered.
In order to provide the technological basis for the agrometeorological forecast of single late rice stripe disease, the data of 95 samples of transplanting rice and direct seeding rice in 10 counties in 2007-2008 and meteorological materials in the same period and counties were analyzed using the applied mathematical statistics method. The result showed that under the condition of rice stripe virus （RSV), the primary factor of affecting the occurring of single late rice stripe disease was rice variety, and the partial correlation coefficient between resistant capability and diseased plant rate was -0.622 (P<0.01). The secondary factor was average relative humidity from seeded or transplanted to seven leaf age, and the partial correlation coefficient with which and diseased plant rate was -0.293 (P<0.01). The affecting from sowed or transplanted date of rice to single late rice stripe disease was actually through average relative humidity from seeded or transplanted to seven leaf age to the breaking out of single late rice stripe disease. Partial correlation coefficients between sowingplanting period of rice and diseased plant rate, average relative humidity from seeded or transplanted to seven leaf age were -0.036 and 0.309 (P<0.01), separately. Therefore, in the operational forecast, the rice variety and relative humidity from seeding or transplanting to seven leaf age should be focused and considered.
2011, 37(9):1145-1150.
DOI: 10.7519/j.issn.1000-0526.2011.9.012
Abstract:
Based on the daily meteorological data observed by 37 stations in Jiangsu Province from 1980 to 2009, the spatiotemporal characteristics of comfort index of human body (CIHB) were studied by use of the linear trend and path analysis. The results indicated that the average annual CIHB index in all Jiangsu and the three partitions (the north of the Huaihe River, the area between Yangtze and Huaihe Rivers and the south of Yangtze River) presents a remarkable increasing trend during the past 30 years, and the linear increasing trend of CIHB in Jiangsu is 0.11/a. Except in summer, the average annual CIHB index of Jiangsu in the other three seasons has an obvious ascendant trend. Increasing is the most prominent in spring and the interannual variation is the most remarkable in winter. In addition, the northsouth difference of CIHB index in autumn and winter is more than that in spring and summer. There is a significant positive(negative) correlation between CIHB and temperature (relative humidity and wind speed), furthermore, the temperature has the biggest impact on CIHB. Although the whole summer CIHB index over the past three decades has no obvious change trend, there is still weak rising trend in July and September since the 1990s. Under the background of the global warming, the research of the characteristics of CIHB climate change may provide scientific basis for people taking effective prevention measures for the variation of meteorological elements and meteorological services about tourism and energy industry.
Based on the daily meteorological data observed by 37 stations in Jiangsu Province from 1980 to 2009, the spatiotemporal characteristics of comfort index of human body (CIHB) were studied by use of the linear trend and path analysis. The results indicated that the average annual CIHB index in all Jiangsu and the three partitions (the north of the Huaihe River, the area between Yangtze and Huaihe Rivers and the south of Yangtze River) presents a remarkable increasing trend during the past 30 years, and the linear increasing trend of CIHB in Jiangsu is 0.11/a. Except in summer, the average annual CIHB index of Jiangsu in the other three seasons has an obvious ascendant trend. Increasing is the most prominent in spring and the interannual variation is the most remarkable in winter. In addition, the northsouth difference of CIHB index in autumn and winter is more than that in spring and summer. There is a significant positive(negative) correlation between CIHB and temperature (relative humidity and wind speed), furthermore, the temperature has the biggest impact on CIHB. Although the whole summer CIHB index over the past three decades has no obvious change trend, there is still weak rising trend in July and September since the 1990s. Under the background of the global warming, the research of the characteristics of CIHB climate change may provide scientific basis for people taking effective prevention measures for the variation of meteorological elements and meteorological services about tourism and energy industry.
2011, 37(9):1151-1157.
DOI: 10.7519/j.issn.1000-0526.2011.9.013
Abstract:
There is a general agreement among the climate scientists that the Earth’s global average surfaceair temperature is now increasing at rates that are without precedent during the last 100 years. Different scales researches to the temperature of surface ground and upper air are the prerequisite for adapting the environment. Microwave Sounding Units (MSU/AMSU) on board NOAA polar orbiting satellites have provided temperatures of deep layers of the global atmosphere since 1978. After corrections such as calibration errors, orbital decay, and diurnal drift, MSU/AMSU longterm data for the upper air have become one of the best references, together with radiosonde observations and reanalysis data. This article elaborates the methods of calibrations, error corrections and merging from different satellites of MSU, and the advancement in the research of the longterm trend.
There is a general agreement among the climate scientists that the Earth’s global average surfaceair temperature is now increasing at rates that are without precedent during the last 100 years. Different scales researches to the temperature of surface ground and upper air are the prerequisite for adapting the environment. Microwave Sounding Units (MSU/AMSU) on board NOAA polar orbiting satellites have provided temperatures of deep layers of the global atmosphere since 1978. After corrections such as calibration errors, orbital decay, and diurnal drift, MSU/AMSU longterm data for the upper air have become one of the best references, together with radiosonde observations and reanalysis data. This article elaborates the methods of calibrations, error corrections and merging from different satellites of MSU, and the advancement in the research of the longterm trend.
2011, 37(9):1158-1165.
DOI: 10.7519/j.issn.1000-0526.2011.9.014
Abstract:
The scientific community that includes meteorologists, physicists and engineers has shown interest in a better understanding of ice accretion formation and related fundamental physics, including atmospheric conditions, surface flow dynamics, droplet trajectory and thermodynamic processes. The rates of ice mass accumulation are highly depended on microphysical factors, including the size distribution of water particles, coefficients of collision, sticking and freezing, and collision speed and angle. These factors are controlled by meteorological parameters, such as precipitation intensity, liquid water contents of cloud and fog, temperature, humidity, wind speed and direction. Such knowledge was built up from field observations and measurements, laboratory studies and model development. The numerical research and prediction on the iceloads and duration of icing get the new advance continuously, and recent numerical models have been developed specifically for icicle and morphogenetic modeling. The physical processes and development of ice accretion models in the past sixty years were summarized. Finally, perspectives for future research are highlighted.
The scientific community that includes meteorologists, physicists and engineers has shown interest in a better understanding of ice accretion formation and related fundamental physics, including atmospheric conditions, surface flow dynamics, droplet trajectory and thermodynamic processes. The rates of ice mass accumulation are highly depended on microphysical factors, including the size distribution of water particles, coefficients of collision, sticking and freezing, and collision speed and angle. These factors are controlled by meteorological parameters, such as precipitation intensity, liquid water contents of cloud and fog, temperature, humidity, wind speed and direction. Such knowledge was built up from field observations and measurements, laboratory studies and model development. The numerical research and prediction on the iceloads and duration of icing get the new advance continuously, and recent numerical models have been developed specifically for icicle and morphogenetic modeling. The physical processes and development of ice accretion models in the past sixty years were summarized. Finally, perspectives for future research are highlighted.
2011, 37(9):1166-1172.
DOI: 10.7519/j.issn.1000-0526.2011.9.015
Abstract:
This paper deals with an automatic observation system with regard to the 34 present weather phenomena. The system works with techniques of photographing and optical scattering as well as the present surface observation system. The automated present weather observing system consists of two parts. One is a present weather sensor, and the other is a digital processor. The present weather sensor collects photographs and optical scattering information. The digital processor, however, processes the photographs, and determines the present weather type with helps of the surface observation system. Achievements were made in realizing the surface coagulation phenomenon by photographing technology.
This paper deals with an automatic observation system with regard to the 34 present weather phenomena. The system works with techniques of photographing and optical scattering as well as the present surface observation system. The automated present weather observing system consists of two parts. One is a present weather sensor, and the other is a digital processor. The present weather sensor collects photographs and optical scattering information. The digital processor, however, processes the photographs, and determines the present weather type with helps of the surface observation system. Achievements were made in realizing the surface coagulation phenomenon by photographing technology.
2011, 37(9):1173-1177.
DOI: 10.7519/j.issn.1000-0526.2011.9.016
Abstract:
The initial effective area is the most important parameter to a piston pressure gauge. The initial effective area and uncertainty of the piston pressure gauge are calculated with a dimensional method, by aid of the dimensional measurement results of the piston and cylinder of the primary piston pressure gauge. The calculation result of the initial effective area of the piston pressure gauge is 1961.0276 mm2, with an extended uncertainty of 4.3 ppm (k=2, 1 ppm=10-6); The initial effective area of the piston obtained with a pressure balance method is 1962.0279 mm2, with an extended uncertainty of 15 ppm (k=2). Therefore, the uncertainty of the piston effective area obtained with the dimensional method is the smallest, and the piston initial effective area is 1961.0276 mm2.
The initial effective area is the most important parameter to a piston pressure gauge. The initial effective area and uncertainty of the piston pressure gauge are calculated with a dimensional method, by aid of the dimensional measurement results of the piston and cylinder of the primary piston pressure gauge. The calculation result of the initial effective area of the piston pressure gauge is 1961.0276 mm2, with an extended uncertainty of 4.3 ppm (k=2, 1 ppm=10-6); The initial effective area of the piston obtained with a pressure balance method is 1962.0279 mm2, with an extended uncertainty of 15 ppm (k=2). Therefore, the uncertainty of the piston effective area obtained with the dimensional method is the smallest, and the piston initial effective area is 1961.0276 mm2.
2011, 37(9):1178-1184.
DOI: 10.7519/j.issn.1000-0526.2011.9.017
Abstract:
The following are the main characteristics of the general atmospheric circulation in June 2011. There was one weak polar vortex center in the Northern Hemisphere. The West Pacific subtropical high is stronger than normal years. In middlehigh latitudes, the zonal circulation is considered as the main characteristics. The monsoon trough is slightly weaker than normal years. The monthly mean precipitation is 102.8 mm, and is 5.9% more than normal. The monthly mean temperature is 20.5℃, and is 1.0℃ higher than normal (19.5℃). The main weather events in June were rainstorm and flooding occurring at the middle and lower reaches of the Changjiang River, South China, etc. There were three tropical cyclones generated and made landfall in China. Extreme high temperature weather occurred in HuangHuai plain, etc. In east of Northwest China, North China, etc., droughts continued until the last ten days of the month. The gale and hail storm disasters happened in 23 provinces (regions, municipalities) in China.
The following are the main characteristics of the general atmospheric circulation in June 2011. There was one weak polar vortex center in the Northern Hemisphere. The West Pacific subtropical high is stronger than normal years. In middlehigh latitudes, the zonal circulation is considered as the main characteristics. The monsoon trough is slightly weaker than normal years. The monthly mean precipitation is 102.8 mm, and is 5.9% more than normal. The monthly mean temperature is 20.5℃, and is 1.0℃ higher than normal (19.5℃). The main weather events in June were rainstorm and flooding occurring at the middle and lower reaches of the Changjiang River, South China, etc. There were three tropical cyclones generated and made landfall in China. Extreme high temperature weather occurred in HuangHuai plain, etc. In east of Northwest China, North China, etc., droughts continued until the last ten days of the month. The gale and hail storm disasters happened in 23 provinces (regions, municipalities) in China.
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ISSN:1000-0526 CN:11-2282/P