Current Issue

28 April 2013, Volume 32 Issue 2   
  • Study on Characteristic of Solar Radiation at Nam Co and Yangbajain in Qinghai-Xizang Plateau
  • 2013 Vol. 32 (2): 315.  DOI:10.7522/j.issn.1000-0534.2012.00031
  • Abstract ( ) PDF (1361KB) ( )
  • The information on solar radiation, especially atmospheric factors and sky condition's quantitative influence on solar radiation is very important for radiation budget in the Qinghai-Xizang Plateau(QXP) as well as for weather and climate in East Asia, while such observation and detailed analysis is few until now. Nam Co and Yangbajain locate in the center of QXP,  the difference between  total solar radiation at Yangbajain and Nam Co is of great significance to regional characteristics of shortwave  in the hinterland of QXP. Using the one-year observed data of total solar radiation of highly temporal resolution and NCEP/DOE reanalysis data, the characteristics and variation of total solar  radiation, and factor influencing the solar  radiation  by shortwave flux transmittance are analyzed. The results show that the shortwave flux transmittance at Yangbajain and Nam Co stations are very high, about 0.807 and 0.817 in completely cloudless sky, its volatility is very low and derives from different altitudes and latitudes. At the same time, the cloud can lessen the disparity of shortwave radiation at two stations, the annual mean flux transmittance is about 0.674 at Yangbajain station, while 0.675 at Nam Co station. What′s more, cloud can make dramatic fluctuations to flux transmittance over time. In  addition, comparing with the ground-based data,  in completely cloudless sky, the total solar  radiation  from NCEP is favorable despite the small error that is about 5.74% at Yangbajain station and 8\^49% at Nam Co station. However, in cloudy day, the relationship between NCEP and observed values becomes much discrete, and NCEP  radiation  has a much systematic larger deviation. Therefore caution needs to be exercised when using NCEP data to analyse solar radiation over the QXP.
  • Variation Characteristics of Radiation Budget and Its Component in the Eastern Qinghai-Xizang Plateau
  • 2013 Vol. 32 (2): 327.  DOI:10.7522/j.issn.1000-0534.2012.00032
  • Abstract ( ) PDF (808KB) ( )
  • Based on the radiation budget observation data from the Automatic Weather Station (AWS) at two  surface stations in Maduo county of  the eastern Qinghai-Xizang Plateau from November 2009 to October 2010, the mean diurnal  and annual variation features of the radiation budget components were analyzed.  The result shows that the mean daily variation and  month mean annual variation of the solar radiation have the same trend at the different underlying surface. The time that appeared zero value of solar radiation in summer is early more than two hours in the morning, and than that in winter and later two hours in the dusk. The solar radiation is the strongest in summer and the weakest in winter. The maximum value appears in July, which is 1.001 MJ·m-2. The minimum value appears in January, which is 0.544 MJ·m-2. The reflection radiation value is the strongest in winter and the weakest in summer from 11:00 to 16:00. It is opposite for the trend of the solar radiation. The maximum value appears in November, which is 0.157 MJ·m-2. The minimum value appears in February, which is 0.326 MJ·m-2. The minimum value of the net radiation appears in December, which is -0.025 MJ·m-2. The maximum value of the net radiation appears in July, which is 0.477 MJ·m-2. The trends of albedo are different at two sites. The season average albedo at the second site is larger 8% than the first site.
  • Impact of the Different Boundary Layer Parameterization Schemes on Numerical Simulation of Plateau Vortex Moving Eastward
  • 2013 Vol. 32 (2): 334.  DOI:10.7522/j.issn.1000-0534.2012.00033
  • Abstract ( ) PDF (1467KB) ( )
  • The Weather Research and Forecasting (WRF) with three planetary boundary layer(PBL) parameterization schemes (YSU scheme, MYJ scheme and ACM2 scheme), a new mesoscale meteorological numerical model and NCEP 1°×1° reanalysis data is used to simulate two low vortex processes moving eastward over the Qinghai-Xizang Plateau during 1-3 July 2008 and 29-31 July 2009, and the simulation of boundary layer over the  Qinghai-Xizang  Plateau is preliminary analyzed. The results show that the simulations with different PBL schemes can preferably reflect the change of track and intensity of the low vortex moving processes during the first 24 h, and the MYJ scheme give better agreement with the observation, while ACM2 scheme has the maximum deviation. The PBL parameterization schemes produce the diverse characteristics of the horizontal wind speed, potential temperature, vertical velocity and the equivalent potential temperature field. The temporal and spatial characteristics of PBL height over the  Qinghai-Xizang  Plateau, which the diurnal change is evident and the spatial distribution in this area are high in the west and low in the east, is simulated by using three PBL schemes. Through the contrast of surface sensible heat and latent heat fluxes, it is found that the local MYJ scheme is appropriate for simulation of latent heat flux and nonlocal schemes (YSU and ACM2 schemes) presents positive deviation of sensible heat flux because of the stronger turbulent exchange and entrainment. Based on the features of research object to choose corresponding PBL scheme, the simulations gets distinct improvement.
  • Analysis of Influence of Dry Intrusion on Rainstorm on 21 July 2008 in Shaanxi Province
  • 2013 Vol. 32 (2): 345.  DOI:10.7522/j.issn.1000-0534.2012.00034
  • Abstract ( ) PDF (2332KB) ( )
  • Based on the NCEP/NCAR reanalysis datasets, the large-scale circulation and water vapor conditions of the rainstorm process on 21 July 2008 occurred in southwest of Shaanxi have been analyzed. By employing multiple variations (such as relative humidity, vector wind, moisture potential vorticity, and vertical vorticity), the characteristics and mechanisms of the dry intrusion, as well as its impacts on the formation, development and maintenance of the  rainstorm  are explored. It is founded that the development of the upper-level trough and low-level cyclone are helpful to the occurrence of  rainstorm  event. The water vapor mainly comes from the Bay of Bengal, The circulation configuration of sustained high-level divergence and low-level convergence is in favor of plenty of low-level water vapor convergence, ascent and condensation motion, which can provide an advantageous condition for the conversion of precipitation. Influenced on moving eastward and development of the upper-level trough, dry intrusion can be mainly observed in two patterns, in the vertical direction, the dry air from the mid-upper troposphere can be extended into the lower troposphere; in the horizontal direction, the dry air can intrude from west to east. The stronger descending motion exists to the  west of  103°E , which could be recognized as the carrier of the dry intrusion. The analysis of moisture potential vorticity and slantwise vorticity theory shows that, when the dry air along with high potential vorticity from mid-upper troposphere intrude into lower troposphere, the slantwise vorticity and low-level vertical vorticity develops due to the conservation of moisture potential vorticity, which facilitates ascend motion brings water vapor upward. When cold air and warm air interacts, the  rainstorm  event happens.
  • Studies on Frequency Density of Inversion Intensity and Height of Atmospheric Boundary Layer in Arid Region of Northwest China
  • 2013 Vol. 32 (2): 377.  DOI:10.7522/j.issn.1000-0534.2012.00037
  • Abstract ( ) PDF (1205KB) ( )
  • The height of the (CBL) in arid region was found to access 4 km in summer. Based on the intensified observational data for  land-atmosphere interaction field experiment performed in a typical arid region, namely Dunhuang, Gansu Province, the characteristics of the atmospheric boundary, the inversion-layer intensity and its frequency density  in arid region of Northwest China are studied using the statistical methods. The extreme value of vertical change of virtual potential temperature is used to determine the heights of convective boundary layer (CBL), stable boundary layer(SBL) and the top of residual layer(RLT). The results show that the  averaged heights of CBL, SBL and RLT are 2.09 km, 594 m and 3.53 km, respectively, and their intensities (Δθv, zi) of inversion layers present obvious diurnal variations that is in 0.084~0.088 K (10 m)-1 on average. The heights of SBL and RLT satisfy very significant Gamma distribution and extreme-value distribution, respectively, both with maximal frequencies are located separately below 1 km height and near 3.8 km height while the height of CBL shows a uniform distribution in the range of 0~4 km on the whole. All of the Δθv, zi of three obeys significant Gamma distribution. Joint frequent densities of the height and the Δθv, zi demonstrate that CBL tends to have Δθv, zi within [0.025, 0.1] K·(10 m)-1 regardless of how much CBL height is, SBL tends to have its height less than 1 km and its Δθv, zi neighboring on 0.1 K·(10 m)-1 and 0.025 K·(10 m)-1, and RLT tends to have its heights in the vicinity of 3.5 km and its Δθv, zi equal to 0.1 or 0.06~0.08 K·(10 m)-1.
  • Variations of the Components of Radiation in Permafrost Region of the Upstream of Shule River
  • 2013 Vol. 32 (2): 411.  DOI:10.7522/j.issn.1000-0534.2012.00040
  • Abstract ( ) PDF (1333KB) ( )
  • The characteristics of radiation on the permafrost region of the upstream of  Shule River are analyzed by radiation data from the measurements of gradient observation system from July 2008 to October 2010. The results show that: (1) The seasonal variation characteristics of monthly total downward shortwave radiation, downward longwave radiation, upward longwave radiation and net radiation are obvious: the maximum value appear in summer or autumn, and the minimum value appear in winter or spring; the seasonality of the monthly total upward short-wave radiation is not obvious; (2) The daily mean downward shortwave radiation, downward long-wave radiation and upward long-wave radiation has seasonality: They drop down to the minimum value in winter (usually in January or December) and rise up to the maximum value in summer (usually in June or July). As for the daily mean upward short-wave radiation, its amplitude of variation is small from January to March and December and large in April and October. (3) The diurnal variation of net radiation is obvious in summer and autumn and the amplitude of variation is large, while the diurnal variation of net radiation is weak in winter and spring and the amplitude of variation is small. The diurnal variations of the components of radiation are all single peak. (4) Surface albedo is small during the growing season and it is big during non-growing season; the variation of surface albedo is remarkable in October and the diurnal variation of surface albedo is ‘U’ shape, with the maximum value in the morning and evening.
  • Comparative Analyses on Some Statistic Characteristics between Cold Front and Mongolia Cyclone Duststorm Processes
  • 2013 Vol. 32 (2): 423.  DOI:10.7522/j.issn.1000-0534.2012.00041
  • Abstract ( ) PDF (1192KB) ( )
  • Using meteorological observation data, the cold-front and Mongolia cyclone duststorm processes occurred in north of China during 2001-2010 were comparatively analysed. The results show that, the occurrences of the duststorm in China decreased in a fluctuating way. The maximum value appeared in 2001,  then decreased annually except a bit increase in 2010. The cold-front duststorm processes happened more often than the Mongolia cyclone type, 60% and 40% of the total occurrence, respectively. Compared with previous related studies, the number of Mongolia cyclone duststorm process showed an evident increasing in recent 10 years. The two types of duststorm processes usually lasted  1~3 days. The average duration day of Mongolia cyclone duststorm process is 1.68 days which is a bit longer than that of cold-front dust storm process (1.54 days). The maximum central pressure of cold high that can represent the cold-front intensity happened in January while the minimum value of central pressure of Mongolia cyclone happened in April. Most of the duststorm processes caused by the cold-front and Mongolia cyclone is dust storm, which taking respectively 75% and 92% of the total processes. For the black storm, it took 9% and 19% of the total processes, respectively. It shown that the Mongolia cyclone duststorm process is stronger than that of the cold-front type. 80% of the maximum wind speed in the two types of processes is between 12~20 m·s-1. The variation of maximum wind speed in Mongolia cyclone dust storm process is less than that of cold-front type. Most of the cold-front dust storms moved towards east and southeast with its main direction NW-SE. They can usually reach Xinjiang Province, the northwest, northeast and the east parts of China. Most of the Mongolia cyclone duststorms can forward to the east, the southeast and the northeast parts of China with its main direction east. Mongolia cyclone duststorms often influence on the northwest, the north and the northeast parts of China. Its coverage is smaller than that of cold-front duststorm.
  • Study of Mesoscale Convective System in Heavy Rainstorm Process at a Cold Vortex Development Stage
  • 2013 Vol. 32 (2): 435.  DOI:10.7522/j.issn.1000-0534.2012.00042
  • Abstract ( ) PDF (1526KB) ( )
  • Using the observation data of Northeastern China heavy rainstorm experiment in 2009, conventional observation data from meteorological observation, automatic weather station, FY-2C satellite and NCEP reanalysis data, synoptic scale characteristic, mesoscale convective system and severe convective trigger mechanism of  mesoscale convective system during a heavy rainstormprocess in Northeastern Chinaon 19 June 2009 are analyzed and a three-dimension concept model of the rainstorm process during the development of the cold vortex is summarized.The results show that, the heavy rainfall mainly happened inthe development state of the cold vortex,and there weresmall scale, suddenness features, which with typical meso β-γ scale characteristics. High temperature, high relative humidity, geopotential unstable layer and high vapor tongue stretched toward the northwestin the low level and the dry air incursionin the middle level provide the extraordinary favorable environment condition for the development of the convective system. The configuration of the two upper level jets intensifys the divergence above the convective area, coupling with the  ahead of the lower level jets on the south side of convergence zone, which strengthens the rising stream of the storm. Sountherly lower level jet of exit region on the south side of upper level jet enhances the inflow intensity of storm which provide the plenty of vapor for the convective systems. The dry air incursion of middle level of western rainstorm make the cold dry air to be rapidly trans port the convective strom occurrence area, which leads to thermo-inversion layer. Before the  convective system happened, the thermo-inversion layer of middle and lower levels the dry layer of upper level is separated, which accumulates the unstable energy of the storm. The low level northwest horizon wind strengthens the convergence of surface stream field, which is the key factor of initial convective systems.
  • Formation Mechanism of Freezing Rain in Hunan Province in 2008
  • 2013 Vol. 32 (2): 456.  DOI:10.7522/j.issn.1000-0534.2012.00044
  • Abstract ( ) PDF (1528KB) ( )
  • Using NCEP reanalysis data, TRMM satellite data, the formation mechanism of freezing rain in Hunan from 12 January to 2 February 2008 was studied through terrain sensitive experiment of WRF numerical forecasting model. The results show that the water vapor convergence and the strong upward movement between the freezing layer and the melting layer are the essential conditions for the formation of freezing rain. The strong water vapor convergenc and upward movement and relatively thick melting layer with high temperature in the center are important to the appearance of strong freezing rain in Southern Hunan. During the strong freezing rain period, bright band in the melting layer can be seen from the satellite image and radar echo intensity is strong. Meanwhile, the relatively high cloud top brightness temperature, no bright band on satellite image and thin melting layer are the features of the weak sleet period. When the influence of actual terrain considered, there is a thickening progress of the frozen layer in the north of Xuefeng mountain area with a obviously low temperature in the cold center. Under the influence of big mountains, water vapor in the melting layer increases, the connective instability in the upper level of melting layer increases, the upward movement enhances and the thickness and strength of melting layer are thicker and stronger than that impacted by the virtual terrain.
  • Simulation Study on Influence of the Convective Parameterization on Tropical Cyclone Prediction
  • 2013 Vol. 32 (2): 468.  DOI:10.7522/j.issn.1000-0534.2012.00045
  • Abstract ( ) PDF (1685KB) ( )
  • The cumulus convection process is one of the most important non-adiabatic physical processes in numerical models. The uncertainty of the cumulus convection process in models affects the accurate tropical cyclone(TC) prediction. Different convection parameterization schemes in models may lead to the different TC predictions. To study the influence of two different convection parameterization schemes on TC prediction, the GRAPES-TCM is used to make sensitivity experiments for 44 TC cases. The 44 cases are from the 9 TCs that made landfall  China in 2008. The two schemes are Kain Fritsch(KF) and Betts-Miller-Janjic(BMJ). The experiment results show that the TC overall prediction with KF scheme is better than that with BMJ scheme. The advantage of BMJ scheme is the intensity prediction of strong TC. The influence of the two different schemes on the TC track prediction has no obvious feature. The influence of the two different schemes on the TC intensity prediction and the TC precipitation prediction changes with the TC initial intensity. The difference of the predicted TC intensity with the two schemes is basically consistent with the difference of the predicted TC precipitation intensity with the two schemes. The difference of the simulated convection with the two schemes leads to the difference of the convective precipitation, which leads to the difference of the latent heat. The difference of the latent heat leads to the difference of  TC intensity. The initial structure′s difference of different intensity TCs causes the difference of the triggered convection with the same scheme.
  • Characteristics of Atmospheric Stratification and Cloud Physics of Different Types of Freezing Rain over Southern China
  • 2013 Vol. 32 (2): 501.  DOI:10.7522/j.issn.1000-0534.2012.00048
  • Abstract ( ) PDF (2517KB) ( )
  • Three classical freezing rain processes over southern China were simulated by observation data and CAMS mesoscale cloud model. Characteristics of atmospheric stratification and cloud physics of the freezing rain and mechanism of freezing rain formation are analyzed. The results show that: (1) a necessary condition for exist freezing rain was the presence of the temperature inversion layer. The inversion layer with high humidity in lower atmosphere often associated with freezing rain. (2) Formation of freezing rain needed to meet three main conditions: freeze layer existed in the upper troposphere, a warm layer and temperature inversion layer existed blow the freeze layer, and cooling layer (temperature below 0 ℃) with high humidity existed near the surface. (3) Two different types of temperature stratification were existed during freezing rain, which are ‘cold-warm-cold’ and ‘warm-cold’ stratification. Corresponding to two types of stratification, two different clouds microphysical structures were existed and two different mechanism of freezing rain formation. Consideration of stratification (‘cold-warm-cold’ layer), the cloud thickness was deeper over Hunan Province on 28 January 2008 and Jiangxi Province on 5 January 2010, and cloud has large amount of ice-phase particles. So clouds belonged to mixed-phase cloud. Freezing rain over Hunan and Jiangxi Provinces  was formed by ice-crystal mechanisms (the melting process). That is, freezing rain developed as falling snow encountered a layer of warm air then the snow completely melted and became rain. As the rain continued to fall, it passes through a thin layer of cold air just above the surface and cools to a temperature below freezing and formed supercooled drops. When the supercooled drops strike ground, or anything else below 0 ℃, they instantly freeze, forming freezing rain. Clouds above freezing rain area over Hunan and Jiangxi Provinces belonged to mixed-phase cloud. However, clouds above freezing rain area over Guizhou Province on 28 January and 9 February 2008 belonged to warm cloud: the cloud thickness was thinner, cloud top temperature was higher, and clouds have little ice-phase particles. Consideration of stratification (‘warm-cold’ layer), freezing rain over Guizhou Province was formed by supercooled warm-rain processes (collision-coalescence process). Supercooled raindrops developed as microscopic cloud droplets collect one another as they fall. Ice processes were not involved in the formation of these raindrops. (4) Over the different freezing rain zone in the same weather systems, the different temperature stratification, cloud microphysical structure and formation mechanism of freezing rain can exist in different types of cloud. The freezing rain zone with same feature can also exist in different weather systems, namely temperature stratification of freezing rain formation, cloud microphysical structure and the mechanism of freezing rain formation are same.
  • Study of the Relationship between Cloud-to-Ground Lightning and Radar Echo of a Severe Squall Line in Shandong Peninsula
  • 2013 Vol. 32 (2): 530.  DOI:10.7522/j.issn.1000-0534.2012.00050
  • Abstract ( ) PDF (1310KB) ( )
  • The evolution characteristics of cloud-to-ground (CG) lightning activity and its relationship with radar echo during a severe squall line in Shandong Peninsula on July 31, 2007 have been studied  using the CG lightning location data from Shandong Meteorological Bureau and the Qingdao Doppler radar base data. The results show that CG lightning was quite active during this squall line, the maximum CG flash frequency was up to 1 212 fl·(10 min)-1, but there were only 15 positive CG flashes during it's lifetime. During the rapid developing stage of the squall line, it can be seen that there were two steep increase periods of flash frequency, and there was a step-shaped trend in CG flash evolution. Most of CG flashes occurred in the regions with radar reflectivity ≥35 dBZ at 6 km altitude. The correlation coefficient between CG flash frequency and intense echo area (≥45 dBZ) was 0.89,  but still there were a few CG flashes scattering in the regions with weaker echo. Further study indicates that there was a strong positive correlation between convective intensity and CG flash frequency. Comparing with 35 dBZ and 50 dBZ, the relationship between CG flash  frequency and the top height of 45 dBZ echo was better, and their correlation coefficient was 0.71. In order to quantitatively analyze the relationship between convective intensity and flash  frequency, eight convective intensity indices have been developed. Among these indices, both the total of intense radar reflectivities (≥35 dBZ) above 0 ℃ level and the total of the products of intense radar reflectivities (≥35 dBZ) above 0 ℃ level and their heights appeared steady relations with CG flash  frequency. Comparing with another weaker convective system, it was found that the stronger the convection, the better the correlation between convective intensity and CG flash  frequency. In addition, both ice precipitation content above 0 ℃ level and that between 7~11 km were also closely related to CG flash  frequency, both  correlation coefficients were greater than 0.8.
  • Study on Wind Power Forecasting of Wind Farm Based on WRF and SVM
  • 2013 Vol. 32 (2): 581.  DOI:10.7522/j.issn.1000-0534.2012.00056.
  • Abstract ( ) PDF (801KB) ( )
  • Based on WRF(Weather Research and Forecasting Model) and SVM(Support Vector Machine)  regression method, short-term wind power forecast system was established. In order to verify the accuracy of WRF, wind speed and wind direction in a wind farm of Zhangbei region in 2006 were hindcasted by WRF model, which were used to compare with the observed data of wind tower at 70 m height. The verification was satisfactory. Wind power forecast model of every 10 min for 30 wind turbines using SVM regression method were developed based on actual wind power recorded data and wind speed, wind direction, atmospheric temperature, relative humidity and atmospheric pressure values which hindcasted by WRF at 70 m height in 2008. For the assessing the forecasting effect of this wind power forecast model, forecasting experiments in 2009 were carried out. The results show that the method to combine WRF model with the SVM method to establish a wind power forecasting produce good prediction results, correlation coefficients ranged from 0.71 to 0.82, normalized root mean square error ranged from 9.8% to 16.5%, and normalized mean absolute error was between 5.4% and 10.5%. The whole year′s correlation coefficient is 0.79, normalized root mean square error is 13.3%, and normalized mean absolute error is 8.3%.
  • Evaluation and Analysis on Climate Condition for New District Planning of Lanzhou City
  • 2013 Vol. 32 (2): 588.  DOI:10.7522/j.issn.1000-0534.2012.00057
  • Abstract ( ) PDF (1688KB) ( )
  • The various meteorological factors in Lanzhou are analyzed using the meteorological data from the stations of Lanzhou, Yongdeng during the period 1978-2007, and the pollution situation of Lanzhou region is simulated from RAMS model under different weather diffusing conditions.  The result show that the most polluted areas of Lanzhou  is in Xigu District, and Honggu District and Gaolan  District s are  lightly polluted areas, but Yuzhong District is easily affected by pollutant. In addition, HYSPLIYT model is used to study the diffusion difference among these stations in the Lanzhou new district using the same pollution source and determine their pollution diffusion abilities and the transmitting route for the polluted air mass under heavy and light pollution situations at these representative sites within 24 h in the different weather conditions. It is found that the  atmospheric diffusion ability of northern Lanzhou is better well than that of its South,  that of West is better than East.  Therefore, the old city of Lanzhou should not be arranged in polluting enterprises. The area near Qinchuan town of Yongdeng county of  the Lanzhou new district is located to be more suitable for the arrangement of heavy industrial enterprisesn  than that of in area of Xicha town of Gaolan county.
  • Analyses on the Heat Wave Events in Shanghai in Recent 138 Years
  • 2013 Vol. 32 (2): 597.  DOI:10.7522/j.issn.1000-0534.2012.00058
  • Abstract ( ) PDF (1227KB) ( )
  • Better understanding on the characteristics of heat wave evolution and occurrence is very important for prevention of its associated disasters. Based on three criterions of the heat wave events, defined according to the threshold of high temperature and warning signal of China Meteorology Administration, the effective accumulated high temperature (EAHT), the maximum temperature of Xujiahui of Shanghai, China during 1873-2010, the multi-scale time-frequency characteristics of the heat wave events in Shanghai is examined. Moreover, the NCEP reanalysis data and the circulation indices of NCC are further employed for analysis of the average atmospheric circulation anomaly. The major results are: (1) The EAHT and occurrence frequency of heat waves can be jointly used for reasonable representation of heat wave-induced hot weather. (2) There are totally 214 heat wave events in Shanghai in the recent 138 years with the average EAHT of 8.3 ℃, and July is more warm than August. (3) There are three major periods when the occurrence frequency and intensity of the heat wave events and EAHT are evidently more than normal, i.e., early 1890s to the end of the century, late 1920s to early 1950s, since the early 1980s especially in the 21st century. The most intensive heat wave occurred in the year of 1934; the frequency of heat wave-induced hot weather increases significantly during the last 10 years. (4) The large scale circulation related to the abnormal partial strong heat wave are mainly featured by the abnormal intensive summer subtropical high over the north hemisphere, the west-drifted west Pacific subtropical high (e.g., 122°E), and the much weakened India-Burma trough compared to the average 1951-2010 years.