ISSN 1000-0526
CN 11-2282/P

Volume 42,Issue 10,2016 Table of Contents

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  • 1  Stochastic Parameterization Toward Model Uncertainty for the  GRAPES Mesoscale Ensemble Prediction System
    YUAN Yue LI Xiaoli CHEN Jing XIA Yu
    2016, 42(10):1161-1175. DOI: 10.7519/j.issn.1000-0526.2016.10.001
    [Abstract](2364) [HTML](596) [PDF 13.54 M](2517)
    Abstract:
    In order to describe the model uncertainly of the GRAPES_MEPS (Global/Regional Assimilation and Prediction System, Mesoscale Ensemble Prediction System), we used Stochastically Perturbed Parameterization Tendencies (SPPT) scheme in this system. The random field which is described with first order Markov chain has a timerelated characteristics and Gaussian distribution, and also has a continuous and smooth horizontal structure since it is a combination through the spectral transform. This paper presents experiments on GRAPES_MEPS ensemble forecasts based on SPPT scheme, with a series of sensitivity tests on random perturbation amplitude and timescale correlation coefficient carried out. Verification on ensemble forecasts is also implemented, and the impact of SPPT scheme on precipitation prediction is analyzed. The experimental results indicate that SPPT scheme can improve forecasting skills of GRAPES_MEPS system and reduce the false negative rate to a certain extent, and improve the prediction of heavy rain forecast skill significantly. Through the sensitivity tests we found that the effect of SPPT scheme for GRAPES_MEPS system is related to the amplitude of the random perturbation field and time correlation scale, more suitable parameters should be determined through sensitivity experiments.
    2  Verification of SMSWARMS V2.0 Model Forecast Results
    XU Tong LI Jia YANG Yuhua WANG Xiaofeng CHEN Baode
    2016, 42(10):1176-1183. DOI: 10.7519/j.issn.1000-0526.2016.10.002
    [Abstract](2008) [HTML](410) [PDF 2.25 M](2562)
    Abstract:
    Forecast products from SMSWARMS V2.0, including rainfall, 2 m temperature, 10 m wind speed, geopotential height at 500 hPa and temperature, wind and relative humidity at 850 hPa are verified. Overall, the forecasts of SMSWARMS V2.0 are significantly improved. The improved TS and ETS of rainfall forecast for all grades indicate that the model can capture the occurrence of precipitation events better. The verification on 2 m temperature also show large improvement. Moreover, the monthly and average monthly mean RMSE value of 10 m wind speed of the new model is lower than the old one. Both 500 hPa geopotential height and 850 hPa wind field from the new model are better, the same results for the correlation coefficient of 850 hPa wind forecast. However, there is little improvement in the 850 hPa relative humidity forecast. Case analysis shows that the heavy precipitation forecast product of SMSWARMS V2.0 has more reference significance than that of SMSWARMS V1.0.
    3  Analysis on a Tropical Cyclone Remote Rain Event in Shanghai in 23-24 August 2015
    CAO Xiaogang WANG Hui
    2016, 42(10):1184-1196. DOI: 10.7519/j.issn.1000-0526.2016.10.003
    [Abstract](1600) [HTML](296) [PDF 7.05 M](2827)
    Abstract:
    Based on routine weather data, meteorological elements fields, wind profiler radar data, satellite cloud images and operational numerical forecast data, we have analyzed a heavy rain event that occurred in Shanghai in 23-24 August 2015. The results show that it was caused by combined action of a remote tropical cyclone Goni and cool air spreading southwards from north area; the circulation of Goni provided the plentiful supply of water vapor and energy required for the event; and the convergence of cool wind and strong easterly jet enhanced vertical motion of moisture air. Verification indicates that there are remarkable bias in rain hit areas, intensity and timing for most operational numerical forecast, which possibly come from the errors in calculation of TC position, strength and location of easterly jet around TC and strength of cool air, etc. Under such situation we should devote much attention to the application of real time observation with the aim of issuing available short term early warning of heavy rain.
    4  Characteristics’ Statistical Analysis of Gust Front Generated by Moving Thunderstorms in Shanghai
    TAO Lan DAI Jianhua LI Baiping CHEN Lei
    2016, 42(10):1197-1212. DOI: 10.7519/j.issn.1000-0526.2016.10.004
    [Abstract](2415) [HTML](230) [PDF 7.40 M](2478)
    Abstract:
    Using conventional weather observations, dual Doppler radar data, Global Forecast System (resolution is 3 km) analysis field data, automatic weather station data, characteristics including synoptic background, sounding and radar features of 18 gust fronts generated by moving thunderstorms from 2009-2014 in Shanghai are analyzed. According to the mutual interaction between gust front and its original thunderstorm, these gust fronts are divided into two types. The first type tends to appear during the developing period of the original storm, moving in the same direction with the thunderstorm while keeping a certain distance, usually accompanied by the elevated rearinflow jet (RIJ) and its lifetime is longer than two hours. The other type usually occurs during the dissipating period of its original thunderstorm, moving far away from the thunderstorm in the same direction (12 cases) or different direction (4 cases). Statistical analysis shows that, as for the first type of gust front, it continuously lifts the warm and moist air in front of the storm while moving in the same direction with the storm. In addition, since the relative strong vertical wind shear and convective available potential energy (CAPE) play an important role in the maintenance of the height of the RIJ, the balance between the positive vorticity generated by RIJ and vertical wind shear and the negative vorticity generated by the cold pool is favorable for the development of the thunderstorm, so the thunderstorms develop and sometimes new storms initiate at the rear side of the gust front. As for the second type, because the gust front moves away from the original storm, and propagates as isolated waves, the cold and dry air at its rear side gradually weakens while affected by the environment. Gust front moving far away from the storm in the same direction cuts off the transport of the warm and wet air into the storm. Simultaneously, in the weaktomiddle vertical wind shear and weaktomiddle CAPE environment, the negative vorticity generated by the downward RIJ and cold pool is stronger than the positive vorticity generated by vertical wind shear, and the updraft leans back over the cold pool. These are unfavorable for the development of the storm. The lifetime of the storm is usually less than 2 hours.
    5  Characteristics Analysis on a Snowstorm in Shandong  Peninsula by Using Multiple Observation Data
    ZHOU Shuling WANG Ke YANG Chengfang ZHOU Yi
    2016, 42(10):1213-1222. DOI: 10.7519/j.issn.1000-0526.2016.10.005
    [Abstract](1986) [HTML](268) [PDF 10.01 M](2762)
    Abstract:
    Using multiple data of Doppler weather radar, windprofiling radar, automatic station, buoy station, conventional sounding and surface observation, the characteristics of occurrence and evolution of one snowstorm event in the east of Shandong Peninsula in December 2014 are analyzed. The results show that firstly, over the Bohai Sea, the 500 hPa temperature is -36℃ or so, the 850 hPa temperature is in the range of -18--16℃, the direction of the Bohai Sea surface wind is northwest and its velocity is more than 12 m·s-1 when the snowstorm occurred. The conventional sounding data show that the mixing layer is below 700 hPa and the atmosphere in the 1000-700 hPa mixing layer is almost saturated. The buoy station shows that the larger airsea temperature difference bewteen the Bohai Sea surface and 850 hPa, and the stronger coastal front in Shandong Peninsula are the critical causes for the snowstorm. Secondly, during the snowstorm, the radar reflectivity is between 30 and 45 dBz. The analysis on the radar echo vertical section of the reflectivity every 6 min reveals that a strong snow echo cell can maintain for one hour. The velocity of Doppler data shows that the distribution of heavy snow cells occurs in the east area of the conversence zone between NE and NW winds. The horizontal wind convergence of coldflow snowstorm mainly exists below 3 km. The wind profile radar data show that there is a lowlevel western breeze under 100 m before the formation of the snowband. The existence of weak northwestern wind in 150-700 m height and the convergence of lowlevel shear line are beneficial to strengthening the convection of snowstorm. When such weak northwestern wind layer disappears, the snowstorm ends.
    6  Possible Causes for the Sudden Drop of Air Temperature in the  Northern Hemisphere from Early to MidWinter
    NIE Yu SUN Leng WANG Dongqian LI Duo
    2016, 42(10):1223-1229. DOI: 10.7519/j.issn.1000-0526.2016.10.006
    [Abstract](1373) [HTML](533) [PDF 5.69 M](2471)
    Abstract:
    During December 2015, the averaged surface air temperature over most regions in the midlatitude of Northern Hemisphere was above normal. Some regions in North America experienced the warmest December in the record. However, the temperature dropped suddenly in January 2016. Extreme cold weather events such as cold surges, winter storms attacked Europe, North America and East Asia. Using the NCEP reanalysis and station observation data, the possible causes for the sudden drop of air temperature during the winter were discussed. The analysis reveals that the Arctic oscillation turned from positive phase in December 2015 to negative phase in January 2016, leading to the warmer Arctic but the colder midlatitude continent. The development and decay of midlatitude atmospheric blocking also contributed to the sudden drop of air temperature. Furthermore, in the context of global warming, the sea surface temperature of tropical eastern Pacific is often above normal during the year of El Ni〖AKn~D〗o, which gives rise to larger temperature gradient between the equator and the pole, causing a more unstable climate system, and further leading to more frequent extreme cold events.
    7  Analysis on Climatic Characteristics of Extreme Precipitating Typhoon in China During 1959-2012
    JIANG Man QI Liangbo
    2016, 42(10):1230-1236. DOI: 10.7519/j.issn.1000-0526.2016.10.007
    [Abstract](1939) [HTML](632) [PDF 1.37 M](3169)
    Abstract:
    Based on percentile analysis, typhoon best track data and daily precipitation data from Shanghai Typhoon Institute of China Meteorological Administration during the period of 1959-2012, extreme typhoonprecipitation for all observation stations are defined, and the extent of influence, precipitation duration and amount anomaly are also evaluated for every typhoon case. A comprehensive index for extreme precipitating typhoon is then established, and 57 cases are determined with their monthly variations and track characteristics being analyzed. The result suggests that the threshold of extreme typhoonprecipitation decreases from Southeast China to Northwest China. The track of extreme precipitating typhoon can be classified into two categories: one goes through Taiwan or its northern ocean and lands in southeast coast of the mainland and the other goes by the offshore or lands in South China. Extreme precipitating typhoons occur more frequently in 1960s-1970s and during years after 2000, with the highest frequency in 1970s and they all occur in the period from May to October and have higher frequency in July and August. Among the 57 typhoons, the scales of typhoon and severe typhoons occur most.
    8  TemporalSpatial Distribution of Bohai Sea SeaIce in LongTime  Series and Its Correlation with Air Temperature
    WANG Meng WU Shengli ZHENG Wei ZHAO Changhai LIU Cheng
    2016, 42(10):1237-1244. DOI: 10.7519/j.issn.1000-0526.2016.10.008
    [Abstract](1392) [HTML](1109) [PDF 4.96 M](2624)
    Abstract:
    Using meteorological satellite data, this paper analyzes the temporalspatial difference of Bohai Sea seaice in winters from 1996 to 2011. The interannual statistics indicate that 2011, 2010 and 2001 are three years with the largest daily ice areas over 30000 km2 while 1999, 2002 and 2007 are three years with the smallest daily ice areas, which are less than 10000 km2. Sea ice mainly concentrates in Laizhou Bay, followed by Bohai Bay and Liaodong Bay. The frequency of sea ice decreases from northeast to southwest and from seashore to deep sea in Liaodong Bay, and from seashore to deep sea in Bohai Bay and Laizhou Bay. By analyzing the ice area data of Bohai sea and accumulated air temperature (≤-2℃) and air temperature at Yingkou Station, we found that the ice area in the Bohai Sea shows a negative correlation with the accumulated air temperature (≤-2℃) and air temperature at Yingkou Station. During the increasing period of sea ice, the ice area shows a significant correlation with the accumulated air temperature, the regression equation about them is derived and the correlation coefficient is -0.90; in the thawing period, the correlation between ice area and the 3 days (that very day and two days before) average temperature is fine, and the regression equation about them is derived the correlation coefficient is -0.84. Finally, the equation for the Bohai Sea ice area forecast is proposed by stages, and the equation is applied to sea ice forecasting test in the 2013/2014 winter. The test result proved the equation is good for the Bohai Sea ice area forecasting.
    9  Verification and Correction of Quantitative Precipitation Estimation for River Basins
    XU Fengwen WANG Zhi DI Jingyue BAO Hongjun ZHAO Linna
    2016, 42(10):1245-1255. DOI: 10.7519/j.issn.1000-0526.2016.10.009
    [Abstract](1386) [HTML](347) [PDF 9.29 M](2544)
    Abstract:
    With the development of fusion technology of multiresource precipitation data, quantitative precipitation estimation (QPE) that combines satellite, radar and conventional meteorological data has got more mature. It has effectively made up the deficienties of low spatial and temporal resolution of conventional meteorological data and offered good opportunities for the application and development of the watershed area precipitation products. At the same time, the testing and the correction of suitability of QPE are the premise and basis for the application of watershed area precipitation. In the paper, based on hydrological precipitation data, statistictesting methods such as the threat score (TS), accuracy rate, falsepositives rate, falsenegatives rate, absolute bias, relative bias, root mean square error and the ROC curve are employed to evaluate the suitability of the QPE of National Meteorological Centre. The error spatial and temporal distribution, the series error in river basin and the quality of different scale precipitation are analyzed. Then, the decreasing average method is applied to optimize and correct the QPE which is based on the error statistics. The watershed area precipitation products are calculated based on the optimized QPE. Lastly, in the case of hydrological element forecast in Linyi Basin, the QPE area precipitation products are found good for the improvement of hydrological forecast. The studies indicate that developing QPE area precipitation products based on fusion technology of multiresource precipitation data can make up the deficiencies of refinement in statelevel forecasting operation of area precipitation and, enhance the technological capacity of statelevel hydrological meteorology.
    10  Cold Air to the Cardiovascular System and Related Influence Factors of Natural Experiment Research
    ZHANG Shuyu ZHANG Xiakun CUI Shijie LIN Chaoxu
    2016, 42(10):1256-1262. DOI: 10.7519/j.issn.1000-0526.2016.10.010
    [Abstract](1563) [HTML](383) [PDF 406.02 K](2098)
    Abstract:
    The effects of cold air on cardiovascular disease were investigated in an experimental research examining blood pressure and biochemical indicators in humans. Zhangye City, Gansu Province was selected as the experimental site. After conducting health screening and blood tests, 30 cardiovascular disease patients and 40 healthy subjects were recruited as case and control groups, respectively. The experiment was performed during cold air exposure in 27-28 April 2013. Blood lipid, whole blood viscosity, cardiac troponin I, myoglobin (Mb), and endothelin1 in all subjects were evaluated 24 h before (morning of 26 April 2013), during the process (temperature dropped to the lowest in 07:00-08:00 BT 28 April 2013), and 24 h after cold exposure (morning of 29 April 2013). The variations in each biochemical indicator were analyzed before, during, and after the cold exposure. The results showed that cold air exposure increased the low and midst shear of whole blood viscosity and the low and high shear of whole blood reduced viscosity. This phenomenon led to excessive blood clotting and high aggregation and viscosity state in cardiovascular disease patients and healthy subjects. In addition, cold air exposure evidently increased serum triglyceride and very lowdensity lipoprotein cholesterol but decreased highdensity lipoprotein cholesterol and Apolipoprotein A1. These indicators caused blood viscosity, increasing cholesterol and platelet granules, which are deposited in the vascular wall, thus further aggravating atherosclerosis. During the cold air exposure, the concentration of vascular endothelin1 significantly increased. Moreover, Mb and cardiac troponin I gradually increased and caused vasoconstriction and damage to myocardial cells. The main conclusions are that the cold air can affect both cardiovascular disease patients and healthy subjects. Firstly, the effect of cold air can make excessive blood clotting and high aggregation and viscosity state, impacting the blood rheology. Secondly, the cold air can promote the occurrence and development of atherosclerosis. Thirdly, the cold air can vasoconstriction and damage to myocardial cells. In addition, the mechanism of the effect of cold air on cardiovascular disease risk factors in humans were also investigated from three aspects.
    11  Study of Sustainable Development Mechanisms About Combination of  Research and Operation (CRO) on Weather Forecasting
    LIN Jian BI Baogui JIN Ronghua ZHANG Xiaoling MAO Dongyan LI Pingyang MENG Qingtao ZHANG Runfu
    2016, 42(10):1263-1270. DOI: 10.7519/j.issn.1000-0526.2016.10.011
    [Abstract](1561) [HTML](440) [PDF 747.62 K](2503)
    Abstract:
    Disconnection between scientific research and operational application has already become an important factor in restricting the transformation of scientific achievement on weather forecast into prediction capacity. On the basis of statement about the necessity of mechanism construction of combination of research and operation (CRO) on weather forecast, current situation at home and abroad, results and experiences of mechanism construction in National Meteorological Centre, China Meteorological Administration (CMA), are presented. After analyzing the problem of CRO mechanism, strategies and proposals are put forward. In addition, special work mechanism about ‘small entity, big network’, selection, admittance, transformation and qualification mechanisms of scientific achievements, scientific research mechanism coming from operation requirement are established so as to ensure the work about CRO put in effect successfully in the CMA Testbed and Proving Ground for Weather Forecast (TPGW).
    12  Abercromby’s Contribution of Meteorology and the Principles of  Weather Forecasting by Means of Weather Charts
    YANG Ping ZHANG Meng XU Xiaofeng
    2016, 42(10):1271-1277. DOI: 10.7519/j.issn.1000-0526.2016.10.012
    [Abstract](1321) [HTML](473) [PDF 2.69 M](2332)
    Abstract:
    Ralph Abercromby (1842-1897) was a famous British meteorologists in the 19th century. He proposed the principles of weather charts and used them in weather forecasting. He opened up the beginning of weather forecast by weather charts analysis. Based on the brief introduction of Abercromby’s life, this paper focuses on his monograph: Principles of Weather Forecasting by Means of Weather Charts. After outlining the work frame and basic concepts, the paper presents Abercromby's understanding of meteorology, including seven types of isobars, classification of the weather type, and how to carry out the weather forecast. Finally, Abercromby's contribution and influence on Meteorology are combed and summarized.
    13  Main Characteristics and Possible Causes for the Climate in China During the Spring of 2016
    SHAO Xie LIU Yanju SUN Chenghu LI Duo
    2016, 42(10):1278-1282. DOI: 10.7519/j.issn.1000-0526.2016.10.013
    [Abstract](1461) [HTML](291) [PDF 4.61 M](2264)
    Abstract:
    In the spring of 2016, the mean temperature of China was above normal, being the second highest in the historical record. The average precipitation amount was also above normal, recorded as the third highest in history. With the influence of the “positivenegativepositive” baroclinic wavetrain in the midhigh latitude of EuroAsia Continent, the northwest of China was controlled by the upper trough, while the northeast was dominated by the circulation of lowlevel convergence and highlevel divergence, which is in favor of more precipitation in these two regions. Moreover, under the influence of El Ni〖AKn~D〗o, the anticyclone anomalous circulation prevailed in the IndianWest Pacific Ocean, bringing plenty of water vapor to the Southern China, and leading to more precipitation there.
    14  Analysis of the July 2016 Atmospheric Circulation and Weather
    QUAN Wanqing HE Lifu
    2016, 42(10):1283-1288. DOI: 10.7519/j.issn.1000-0526.2016.10.014
    [Abstract](2161) [HTML](437) [PDF 4.46 M](3398)
    Abstract:
    The following are the main characteristics of the general circulation of atmosphere in July 2016. There was a single polar vortex center with eccentricity features in the Northern Hemisphere, and the strength of the polar vortex was stronger than normal. The midhigh latitude circulation distributes in a 4wave pattern. The strength of subtropical high in the Northern Hemisphere was stronger than usual, the location of northwestern Pacific subtropical high was by south and the ridge line oscillated greatly. In July, the monthly mean temperature of China is 22.6℃, 0.7℃ higher than usual. The monthly mean precipitation of China is 131.8 mm in July, 9.3% higher than usual, and much more significant in North China, Jianghuai and Jiangnan regions. The heavy precipitation processes in July were mainly in North China and southern China, and there were eight regional torrential rain processes. What’s more, the rainstorm from 18 to 22 July broke the extreme values in historic records in many aspects. Four typhoons formed in the Northwest Pacific in July, of which three were active and two of them landed in China. The forming time of the first typhoon in 2016 is the second latest in records since 1949. In addition, drought occurred in the northeast of Inner Mongolia region; heat wave continued in Middle China, East China and Xinjiang Region, lasting as long as 11 days and affecting 1075 observation stations. The extreme high temperature was found in Turpan, being 46.8℃.

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