Plateau Meteorology

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28 October 2013, Volume 32 Issue 5   
  • Impact of the Anomaly of Surface Sensible Heat in Qinghai-Xizang Plateau and Its Surrounding Areas on Summertime Precipitation in Northern Xinjiang
  • 2013 Vol. 32 (5): 1215-1223.  DOI:10.7522/j.issn.1000-0534.2012.00117
  • Abstract ( ) PDF (1148KB) ( )
  • As well known, the surface thermal anomaly (STA) in the Qinghai-Xizang Plateau (QXP) have important influences on the climate in China. Previous studies were focused on the effects of the STA on the weather and climate in eastern monsoon regions, less attention was paid to the connection between the STA and the precipitation in arid regions, especially in Xinjiang. In this paper, the preliminary results of the relationship between the STA in  QXP and summer rainfall in northern Xinjiang were given. Using the NCEP/NCAR reanalysis monthly mean data and  precipitation data at 43 stations in northern Xinjiang, the relationships between the anomaly of surface sensible heat (SH) in  QXP and its surrounding areas and the summer precipitation in northern Xinjiang were analyzed. The results showed the effects of the SH in the QXP, eastern QXP and western QXP (divided along 90°E) on the summer time precipitation are different and the SH in eastern QXP have the most closed relation with summer precipitation. When the SH weakened in  QXP and strengthened on the northwest side of the QXP, the South Asia High has two positive centers, which is one of the most important circulation patterns for occurring more summer rainfall in northern Xinjiang, and there are an anomalous cyclone over central Asia and an anomalous anticyclone over the Baikal Lake, respectively, which results in the anomalous south wind prevailing and is favorable to the warm-wet air move from the low latitude regions. In addition, the transportation of water vapor by Somalia jet  is unusually strong, passing over the Equator, and at the same time the Arabian Sea is controlled by anomalous anticyclone circulation, driving the water vapor to be transferred continuously to the central Asia and Xinjiang, so the south water vapor channel which impacted Xinjiang is strengthened significantly. Above all are contributed to the occurrence of more summer precipitation in northern Xinjiang, and vice versa.
  • Numerical Simulation of Summer Boundary Layer Structure over Undulating Topography of Loess Plateau Simulated by WRF Model
  • 2013 Vol. 32 (5): 1261-1271.  DOI:10.7522/j.issn.1000\|0534.2012.00121
  • Abstract ( ) PDF (1232KB) ( )
  • Two planetary boundary layer (PBL) parameterization (YSU and MYJ) schemes in Weather Research Forecasting (WRF) numerical model were used to simulate the PBL structure, net radiation flux, sensible heat flux, latent heat flux and soil heat flux in the undulating topography of Loess Plateau during July 27-29, 2009. The two schemes include a first\|order closure schemes: the Yonsei University (YSU) PBL scheme, and a turbulent kinetic energy (TKE) closure schemes (the Mellor\|Yamada\|Janjic (MYJ) PBL scheme). The simulated results are compared with the observations provided by Semi\|Arid Climate Observatory Laboratory (SACOL) of Lanzhou University. The compared results reveal that WRF model has good quality in simulating the diurnal characteristic of surface temperature. On the other hand, the simulation of the wind speed is poor, that has a great relationship with the random variability of the wind field itself. The landuse type, soil type and soil moisture provided by model have a great influence on latent heat flux simulated during the day. The maximum height of convective boundary layer of semi\|arid area of the Loess Plateau can reach 2 500 m, the nighttime stable boundary layer height at the generally exceeds 700 m. In regard to PBL structure, a non\|local scheme with the entrainment flux proportional to the surface flux is favourable under unstable conditions. Under the stable condition, the local TKE closure scheme perform better than the first\|order approaches.
  • Observation Study of Aerosol over Mid-Western North China Plain in Autumn (October)
  • 2013 Vol. 32 (5): 1308-1320.  DOI:10.7522/j.issn.1000-0534.2012.00123.
  • Abstract ( ) PDF (1340KB) ( )
  • Measurements of atmospheric aerosols over the mid-western region in North China Plain were conducted using the modified Particle Measuring Systems on board the Cheyenne aircraft by the Weather Modification Office of Hebei Province. The vertical and horizontal distributions of aerosol number concentration (ANC) and size distribution under different weather conditions were studied using the observations from 19 flights in October 2010. The results show that the aerosols over the study region mainly come from the underlying surface which are controlled by the inversion layer and wind shear in the boundary layer. The observed surface ANC is 1 000~3 000 cm-3 and the average diameter is 0.18~0.20 μm. It is found that the ANC is lower over Shijiazhuang area than that of Xingtai aera, The ANC over Boxiang county is close to that of Shijiazhuang area. The ANC (1 075~4 019 cm-3) is the highest near the surface and decreased exponentially with height. Under the high clouds, ANC shows the linear distribution in the lower part and negative exponential distribution in the higher part of the boundary layer. ANC is related to weather conditions and it has the minimum value after light rain (102 cm-3 near the surface) and could reach 103 cm-3 under the sunny days or days with dense clouds and high clouds. The diurnal variation of surface ANC shows a maximum value in the morning (1 799 cm-3) and a minimum value at noon (706 cm-3), and a rapid increase in the afternoon. The average ANC is 994 cm-3 in the evening. The vertical distribution of ANC is steep at noon and flat in the morning and afternoon with a collapse below the boundary layer. Accumulation of aerosols near the surface could easily lead to air pollution. Diurnal variation of temperature inversion layer also affects the diurnal variation of  aerosol vertical distribution. The aerosol size distribution shows a single peak at 0.11 μm in most of the time and had the widest spectrum at noon. It narrowed down with height and broadened under unstable and high humidity weather conditions.
  • Climate Intraseasonal Oscillation of Heavy Rainfall Process and Its Application in Extend-Range Forecast
  • 2013 Vol. 32 (5): 1329-1338.  DOI:10.7522/j.issn.1000-0534.2012.00125.
  • Abstract ( ) PDF (1005KB) ( )
  • Low frequency oscillations (LFO) with periods over 10 d under intraseasonal scale are important means for extend-range forecast becauseof its relative longer predictabilitythan synoptic scale perturbation with high frequency. In this paper, taking Shanghai as an example, using the daily rainfall observation in Shanghai and global NCEP/NCAR reanalysis atmospheric circulation data for the period of 1960-2010, climate intraseasonal oscillation (CISO) of heavy rainfall process (HRP) in Shanghai is firstly investigated by means of a new kind of nonlinear serial signal processing method named as EEMD (Ensemble Empirical Mode Decomposition). And forecast effects on HRP basing on CISO are then evaluated. Finally, improvement experiments are tested by combining CISO of HRP and their relating LFO of atmosphericcirculation. The results show that: (1) Positive (negative) phases of LFO with periods over 30d are consistent with active (break) periods of HRP during rainy season. While LFO with 10~30 d periods can not only modulate occurrences of HRP during the two active periods but also do contribution to severe rainfall stage during mid-summer. (2) 2/3 HRP occurrences during rainy season can usually be predicted basing on CISO of HRP, which may be an important clue for its extend-range forecast. (3) HRP in Shanghai usually isin close association with LFO convergences under both 10~30 d and over 30 d intraseasonal scale from both south and north directions. The LFO of west Pacific subtropicalhigh and north systems exert important influences on continuous HRP lasting for more than 5 d. And the forecast effects can be improved by combining CISO of HRP and their relating LFO of atmosphericcirculation, which may be a kind of means with certain value in practice of extend-range forecast.
  • Forecasting Studies of Dynamic Factors in Rainstorm Process with Easterly Wave
  • 2013 Vol. 32 (5): 1339-1348.  DOI:10.7522/j.issn.1000-0534.2013.00089.
  • Abstract ( ) PDF (1499KB) ( )
  • In order to study the dynamic factors in the easterly wave  rainstorm occurring in the coast of Fujian and Zhejiang Provinces on 24-27 July 2010, using the 6 h, 12 h and 24 h GFS forecasting data of NCEP/NCAR, the moist thermodynamic baroclinic vorticity, second-order potential vorticity and potential wave-activity density were calculated. The abnormal values of these dynamic factors serve as criterion to judge the future precipitation area. In nature, this kind of easterly wave rainstorm forecast is the dynamically extended release of GFS forecast data. The calculated results reveal that these dynamic factors are skillful for the 6~12 h forecast of precipitation on July 25, show the prediction ability to the observed precipitation area. The precipitation forecasting of these factors is slightly different. The forecast of second-order potential vorticity and wave-activity density is superior to that of the moist thermodynamic baroclinic vorticity. The difference is mainly caused by the fact that these factors include different physical informations while the physical factors playing a leading role in any  rainstorm event are not the same. For example, filtering out a large-scale background without direct influence on precipitation, and retaining meso- and small-scale information, the wave-activity density indicates well the observed precipitation area.
  • Validation and Comparison of Regional Fog Forecast by MM5 and MM5-PAFOG Models
  • 2013 Vol. 32 (5): 1349-1359.  DOI:10.7522/j.issn.1000-0534.2012.00126.
  • Abstract ( ) PDF (1181KB) ( )
  • MM5 and PAFOG models were run to forecast daily regional fogs in eastern China from October to November of 2010. PAFOG model was run at each observational station with the initial and boundary conditions (IC/BC) from MM5 model. Fog was diagnosed based on the multi-variables of MM5 model output and forecasted by the visibility of PAFOG model. The results were evaluated against 3 h (or 6 h) routine observations at all stations of China Meteorology Agency (CMA) observational net works by calculating a set of scores for eastern China and Anhui Province, respectively. The evaluated results show that: (1) Both methods have a certain capability of forecasting the regional fog, with the common shortcoming of high false alarm rate. The values of TS/ETS from based on MM5 model are 0.075/0.065 for eastern China and 0.094/0.081 for Anhui Province, and the hit rate is 0.296 for eastern China and 0.378 for Anhui Province. (2)The TS/ETS values from based on  PAFOG model for eastern China and Anhui Province is 0\^038/0.027 and 0.053/0.038, respectively, lower than those of MM5 model; however, the hit rates is 0\^387 for eastern China and 0.517 for Anhui, higher than those of MM5 model. (3) Based on the daily statistic, MM5 model outperforms PAFOG model in eastern China, while PAFOG  model outperforms MM5 model slightly in the inland province (Anhui Province); and PAFOG  model  tends to over-predict fog occurrence more than MM5 model. (4) If the weather records of the past 1 h were used for model evaluations, the validation results for both methods would be improved.
     
  • Turbulent Statistic Characteristics of Wind, Temperature and Humidity during Autumn Fog in Urban Area of Tianjin
  • 2013 Vol. 32 (5): 1360-1367.  DOI:10.7522/j.issn.1000-0534.2012.00127.
  • Abstract ( ) PDF (714KB) ( )
  • Based on the turbulent data, wind, temperature, relative humidity and visibility data at 250 m meteorological tower in Tianjin city, the turbulence characteristics of atmospheric surface layer during autumn fog were discussed. The results show that the normalized standard deviations of temperature and humidity over urban area decrease with increasing instability under unstable conditions and the values are obviously larger than those over Kansas prairie and cropland, which cannot obey classical Monin-Obukhov similarity theory. However, the normalized standard deviations of three dimensional wind velocities in unstable conditions increase with instability and obey a 1/3 power law of Monin-Obukhov similarity theory during autumn fog, with their values being 2.5, 1.9 and 1.2,  respectively for three directions in the condition of near neural stratification. The scatter of normalized standard deviations of temperature and humidity increases under stable stratification conditions, while it is not obvious for wind velocity. During the dense fog process over the urban area, atmospheric stratification changes from strong stable before fog to near-neutral stratification during the fog. Prior to the fog formation, the range of stability parameter is from -10 to 10.The value varies from -2 to 2 on a smaller scale during the fogprocess. It varies between -5 and 10 after fog dissipation.
  • Forecast Examination of Surface Global Horizontal Irradiance over Middle of Xinjiang Using WRF Model
  • 2013 Vol. 32 (5): 1368-1381.  DOI:10.7522/j.issn.1000-0534.2012.00128.
  • Abstract ( ) PDF (1792KB) ( )
  • Based on the historical weather forecasts adopting WRF model driven by GFS initial field in January, April, July, October and December of 2009 at Dabancheng\_Xiaocaohu wind farm where wind power prediction model was established according to the combination of dynamic and statistical methods, the forecast accuracy of downward short wave radiant exposure (SWREDOWN) replacing global horizontal irradiance (Eg) was also examined at Turpan, Urumqi and Yanqi meteorological stations. The results are  as follows: (1) Mostly, the hourly SWREDOWN in WRF model can display the variation tendency of Eg on surface. The mean absolute percentage error (MAPE) of hourly Eg prediction is smaller in afternoon, second in morning, and the bias at sunrise is more than 3～4 times larger as compared to sunset. (2) At Turpan and Urumqi station, the MAPE of daily Eg prediction is less than 25% on the condition that the ratio of the Eg on surface to the horizontal extraterrestrial irradiance is more than 0.4, otherwise the prediction is worthless, while it is not sensitive to the ratio at Yanqi station.(3) At Turpan station, the best forecast effect of Eg is in October, second in April, while at Urumqi and Yanqi stations, the best is in April, second in October, and the worst are all in winter months, because during the period there exist the biggest ratio of scatter irradiance to Eg on surface through a year and shortage of predicting ice and snow effect in model, so it is improper to adopt a same set of parameterization scheme or MOS equation on predicting Eg. (4) There is some closed co-relationship between the irradiance and wind field because their seasonal and diurnal bias variation characteristics are similar.
  • Synthetic Analyses on Environmental and Physical Field of Rainstorm in Early Summer in Wangmo, Guizhou
  • 2013 Vol. 32 (5): 1400-1413.  DOI:10.7522/j.issn.1000-0534.2012.00131.
  • Abstract ( ) PDF (2283KB) ( )
  • Using 1°×1° reanalysis data from the  NCEP/NCAR, TBB data of FY-2C, and the hourly precipitation data for these two elements,  the environmental and physical field at stage prior to the occurrence of torrential rain storm, developing, mature, and dissipation stages were synthetic analyzed to selecte five similar rainstorm processes in early summer in Wangmo. The results show that the main influence systems are plateau short wave trough, low-level shear line, low-level jet stream and weak surface cold air. The interactions of these systems induce the frontogenesis of surface convergence line to finally result in the torrential rainstorm. The rainstorm in Wangmo mainly occurs from 23:00 to 03:00 (Beijing time). The formation and evolution of MCC or quasi-MCC have direct influence on the rainstorm in Wangmo. The key area is located in high moisture unstable stratification and the positive vorticity convergence zone before the torrential rainstorm occurring. At the mature stage of torrential rainstorm, the structural characteristics of low level convergence and high level divergence are prominent. The heavy precipitation caused by frontogenesis occurs in the south of front and north of warm-moist air. The frontogenesis function reveals that frontogenesis in low level troposphere occur near 800 hPa. Negative non-equilibrium forced area is located in southwest Guizhou. The strongest moment of the negative center is about 10 h before the peak of heavy precipitation, it might be a start mechanism of heavy precipitation. The synthetic analysis reveals the commonality of the formation of torrential rainstorm in Wangmo,  provides a way for forecasting this type of torrential rainstorm in the future. However, this method may be also some  smooth characteristics, to analyze or forecast a process, the strength of systems and physical quantities might be different.
  • Change Features of Different Types and Grades of Precipitation Event in Northeast China in Recent 50 Years
  • 2013 Vol. 32 (5): 1414-1424.  DOI:10.7522/j.issn.1000-0534.2012.00114.
  • Abstract ( ) PDF (1106KB) ( )
  • Using the daily precipitation data and daily temperature data at 90 weather stations in Northeast China from 1961 to 2010, the climate characteristics, trends and variation field characteristics of different grades in precipitation events have been studied. The results show that the trend of annual mean temperature increases in the past 50 years, with higher increasing rate than other areas of China. An abrupt change temperature occurred in 1987, followed by a sharp increase in temperature. Annual precipitation and precipitation days  decrease, with the decrease of annual precipitation days being more obvious, which is mostly due to the decline in light rainfall (days). Annual rainfall (days) shows the increasing trend, with annual snowfall (days) showing a decreasing trend. Annual precipitation decreases from southeast to northwest, and the annual number of precipitation days is larger in the east and north. The proportion of extreme heavy precipitation and different grade snowfall increase after temperature has abrupt change. The fluctuations of annual precipitation (days) also become larger after 1987, which may be the main reason of increase of extreme drought and flood events in Northeast China. The seasonal distribution of precipitation also shows significant changes. Rainfall (days) in summer and autumn are reducing, and rainfall (days) in spring and snowfall (days) in winter are increasing, which will be beneficial to maintain the soil moisture in winter and snow in spring.
  • Characteristics of Temporal-Spatial Distributions of Heavy Rainstorm in Hunan and Its Typing
  • 2013 Vol. 32 (5): 1425-1431.  DOI:10.7522/j.issn.1000-0534.2012.00132.
  • Abstract ( ) PDF (784KB) ( )
  • Using the  meteorological data at 97 stations in Hunan from 1952 to 2010 and NCEP reanalysis data, and statistical analysis and other methods, the spatial and temporal distributions of the heavy rainstorm in Hunan were analyzed. The result shows that the station number in  rainstorm process of Hunan in the past 59 years appears increasing trend,  the heavy rainstorm processes over the years are total 376 times, which mainly occurs in the main flood seasons (from June to August), accounts for 70.7%,  and the peak is in June. The longest process of heavy rainstorm is 6 days, 79% is about 2 days. The  prone frequency areas of  heavy rainstorm mainly located in western and northern Hunan, but south-western Hunan, some counties of Chenzhou, most counties of Changsha and Loudi are the less prone areas. Through the analysis of the circulation characteristics in 376 rainstorm weather processes, 5 types of weather system typing with  trough + shear + frontal type, low vortex shear + frontal type, subtropical high edge type, tropical depression type (including typhoon, low and tropical convergence), and easterlies  with  type are established. The objective quantitative factor closely with heavy rainstorm are statistically analyzed based on the physical quantity field of T639L60, which summed up the eight weather models, and building the heavy rainstorm forecasting conceptual model which include high and low air circulation configurations, power, thermal conditions and heavy rainstorm areas, etc. provid the reference for heavy rainstorm forecast.
  • Quality Control of Surface Radiation Data Measured in Dali National Climate Observatory
  • 2013 Vol. 32 (5): 1432-1441.  DOI:10.7522/j.issn.1000-0534.2012.00133.
  • Abstract ( ) PDF (1043KB) ( )
  • Because of operation-related problems， zero drift of the sensor， virtual connection between data acquisition equipment and lightning protection board and so forth， some measurement error and various degrees of missing data occurred in long-term and continuous observation for CNR1 Net Radiometer in Dali National Climate Observatory. This study adopts quality control procedures including missing value check，  zero drift correction， ‘physically possible’ ranges check， ‘extremely rare’ ranges check and ‘comparison between the observed and estimated value’ check， with the data of global solar radiation， reflected short-wave radiation， atmospheric long-wave radiation and surface long-wave radiation measured in Dali National Climate Observatory in 2010. The result shows that： (1) models for estimating global solar radiation， atmospheric long-wave radiation and surface long-wave radiation are reasonable， and the estimated value shows good correlation with the observed value with index of agreement over 0.89； (2) measurement error caused by zero drift of short wave radiation sensor is not negligible， and it must be corrected while application； (3) global solar radiation and reflected short-wave radiation after zero drift correction are of high reliability, and their accurate rate are 99.02% and 99.92%, respectively; while atmospheric long-wave radiation and surface long-wave radiation are of low reliability, and their accurate rate are 70.67% and 73.49%, respectively.
  • Analyses on Climatic Characteristics of Thunderstorm in China in Recent 30 Years
  • 2013 Vol. 32 (5): 1442-1449.  DOI:10.7522/j.issn.1000-0534.2012.00134.
  • Abstract ( ) PDF (973KB) ( )
  • The features of spatial and temporal distribution, annual variability and abnormal changes of the thunderstorm are made with EOF and main function analysis  using the thunder observation data from 1981 to 2010. The results show that the distribution of annual thunderstorm day in China is divided into 4 sub-regions. The highest one is in southeast of China, the other highest in southwest of China, the higher in northeast and north China, the lowest in northwest of China. The number of annual thunderstorm shows much less in winter than in summer, meanwhile thunderstorm appears more in the time from the afternoon to evening. The annual thunderstorm days show two periods of high value in 1980s and 2000s and a low period in 1990s and high value of the period in 2000s is because of the increases of thunderstorm events in the afternoon and evening. In the past 30 years, the thunderstorm in northern China shows an overall reduction while changed from decrease into increase in southern China, the interdecadal variation of anomaly field is more obvious. The variance contribution of the first principal component accounts for about 32.4% and the spatial characteristic appears the different-shaped between north and south. The rest vector fields also show abnormal regional changes in different levels. The percentage of the first 12 principal component's cumulative variance contribution is 80.9%. In addition, the ENSO events have certain impact on thunderstorms in China especially in the southern region of China, the manifestation between Guangdong, Guangxi and Yunnan, Guizhou show the opposite anomaly performance.
  • Analysis and Application of Dual-Polarization Parameters about Ground Clutter from X-Band Weather Radar
  • 2013 Vol. 32 (5): 1478-1484.  DOI:10.7522/j.issn.1000-0534.2012.00137.
  • Abstract ( ) PDF (812KB) ( )
  • X-band dual polarization radar is taken as the test platform at the key laboratory of atmospheric sounding of China Meteorological  Administration. Statistical characteristics of dual-polarization parameters of ground clutter that differentiated from weather echoes were analyzed by radar echoes with low elevation angle in the clear and precipitation condition of Chengdu in summer of 2010. The results show that the correlation coefficients  of most ground clutter are less than 0.85, while the correlation coefficients of most weather echoes are greater than 0.90. The differential reflectivity of ground clutter is randomly polarized, the intensity distribution covers between -20~20 dB, and the mean concentration is 0 dB and the weather echoes are concentrated between -3~6 dB; The KDP of ground clutter covers the entire π interval, and the KDP of weather echoes are concentrated from -6 to 6°·km-1. Test data show that the KDP distinguishes the difference between clutter and weather echoes obviously. The important parameters of identifying ground clutter are KDP, ZDR and ρhv. Base on the occurrence possibility of polarized parameters about clutter and weather echoes, fuzzy logic is utilized to identify ground clutter. Furthermore, the calibration of ZDR is taken with ground clutter. The standard variance of ZDR bias is -2.15 dB, and the short-term mean of ZDR bias is 0.28 dB within four hours.
  • Analysis on Severe Convective Weather Characteristic in Henan Based on Flow Pattern Identification and Physical Elements
  • 2013 Vol. 32 (5): 1492-1502.  DOI:10.7522/j.issn.1000-0534.2012.00139.
  • Abstract ( ) PDF (1098KB) ( )
  • Using the conventional high, surface observations, sounding and radar data, the meso-scale weather comprehensive analysis and the physical parameter analysis, the occurring and developing environmental conditions of thunderstorm wind and regional hail in Henan region from May to September of 2001-2010, and the characteristics and regular patterns of three types of severe convective weather in Henan Province were studied. (1) The typical features of severe convective weather in henna are summed four conceptual models of mesoscale weather analyses are established, that is, northeast vortex at the back of vortex trough, north vortex, low trough and the southwest airflow on the edge of the subtropical high, the key elements and the quantitative reference indices of severe weather analyses under different flow patterns are provided. (2) On the basis of circulation classification, the organic relation and significant differences of different weather situations, different types of severe convective weather and different physical parameters are discussed from the thermal, dynamic, water vapour and other basic conditions of severe convective weather. The sensitive physical parameters and element characteristics are found by analysing three types of severe convective weather thunderstorm winds, hail and gale hail, the indicators and thresholds of physical elements of the different severe convective weathers are summed up, which provide reference for forecasting and early warning for the future thunderstorms, hail and other severe convective weather. (3) The evolution features of occurrence, development, movement and so on about the severe convective weather radar echo systems in different flow patterns are briefly concluded by analysing radar echoes of the severe weather cases.
  • Climatic Linkages between SHWP Position and EASM Rainy-Belts and-Areas in East Part of China in Summer Half Year
  • 2013 Vol. 32 (5): 1510-1525.  DOI:10.7522/j.issn.1000-0534.2013.00033.
  • Abstract ( ) PDF (2390KB) ( )
  • To better know and understand the precipitation climate of East Asian Summer Monsoon (hereafter EASM) in the east parts of China in summer half year， in this paper the climatic linkages between both the position of the Subtropical High over the West Pacific(SHWP) and the EASM rainy-belts and -areas have been explored， utilizing the observed daily precipitation data in China for 1951－2005 and the US NCEP/NCAR reanalysis  data for 1982－1994， and the secular pentad mean position figure for the West Ridge Point(WRP) of the SHWP and the pentad mean rainfall figures for many stations. Main conclusions are as follows：  (1) There are the closed relationship between the WRP position of the SHWP during the periods of both  its relative stable stages and its east- or west-ward， abrupt and largely， moving ones and the EASM rainy-belts and -areas in east part of China in summer half year. On the average， in the northward advance period of the SHWP， if the WRP  stay quiet steadily over off the northwest coast of Philippines， Taiwan Strait and its northwest side， and off the southwest coast of Japan， it will bring about pre-summer rainy period over South China(SC) in Pentads 28－33， the Meiyu one over the Changjiang and Huaihe Valley(CHV) in Pentads 35－40， and northern one in North China(NC)， Northeast China and the northeast part of Northwest China(NWC) in Pentads 42－49， respectively；  in the southward retreat period of the SHWP， once the WRP  westward quickly extending to north parts of Taiwan Strait， Fujiang and Jangxi Provinces(off the coast of Guangdong and Guangxi Provinces)， it will bring about the autumn rain over NWC(SWC) in Pentads 50－52(55－61)， respectively；  If the WRP eastward， suddenly and largely， moving out of South China Sea in Pentads 27－28， the pre-summer rainy period in SC will begin with mid-May. (2) Exploring the  facts that the precipitation climate for both the Guanzhong-Hauzhong and the rest part in East parts of NWC are, mainly, influenced by the Meiyu and the Northern rainy periods, respectirely and so on. (3) Both the long sequence pentad mean rainfall figures and the pentad mean position ones of the WRP of SHWP are the important stool figures for  the EASM precipitation analysis and forecast.

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