应用气象学报

INTRODUCTION OF A SIMPLIFIED PHOTO-CHEMICAL SCHEME INTO MULTI-BOX MODEL CAPPS FOR URBAN AREA OZONE PREDICTION

Zhang Kai, Xu Dahai, Zhu Rong, Chen Junming

2005, 16(1): 1-12.

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Abstract:
This paper describes the introduction of a photo-chemistry model based on a highly parameterized chemistry mechanism into the nonstatic atmospheric advection-dispersion box-model to practise ozone prediction in urban boundary layer. Genetic algorithm is employed to inverse the VOC (volatile organic compounds) concentration as well as NO_X source strength since the ambient pollutant concentration and emission data for urban area are insufficient. this work gives the birth to a new version of the City Air Pollution Prediction System (CAPPS) with the atmospheric chemical processes included. Based on regular sounding data and the pollutant concentration data collected at Beijing Dance Academy, testing predictions of ozone and NO_X are performed using the new single-box model. The results indicate that the new model is proved to be an effective tool for urban area ozone prediction.

NUMERICAL SIMULATION OF LAND SURFACE PROCESS AND ATMOSPHERE BOUNDARY LAYER STRUCTURE OVER SMALL HILL UNDERLYING SURFACE

Hu Xiaoming, Liu Shuhua

2005, 16(1): 13-23.

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Abstract:
A modified parameterized method of land surface physical process and a 3-dimensional transfer model are used for simulating features of surface heat flux, surface temperature, temperature profile, humidity profile, turbulence energy and so on over a small hill underlying surface.The result show s that the wind field is affected by the topography, also the turbulence transfer is affected, and the influence make the atmospheric temperature near g round surface behind the hill higher than that in front of the hill.The result is reasonable and the simulation is satisfactory.In addition, the model can also be used for other homogeneous and inhomogeneous terrain and mesoscale model.

A REGIONAL SCALE CLIMATIC MODEL OVER THE CHANGJIANG DELTA:DEVELOPMENT, EVALUATION AND ANALYSIS

Liu Hongli, Li Weiliang, Zhou Xiuji, Qin Yu

2005, 16(1): 24-34.

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Abstract:
A new regional climatic model was developed and proof-tested by simulating the frontal rainfall, cyclonic rain and shower.The effect of different physical processes and different time step in the model was analyzed in order to choosing the approopriate experimental project. Using this model simulated the climatic effect of the change of land-use in Changjiang Delta area.Result s show that vegetation reducing and urban extending are main causes of the regional climate change.The range of seasonal temperature would increase and the humidity would decrease if the vegetation reduced.With the urban area extending the urban heat island effect would be intense also.

PRELIMINARY RESEARCH ON MONITORING SNOW-COVER OVER CHINA WITH AMSU DATA

Chen Aijun, Liu Yujie, Du Bingyu

2005, 16(1): 35-44.

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Abstract:
The territory of China was divided into five areas, and a primary method for each area was proposed to monitoring snow-cover over China, using the data from channel 1, 2, 15 of NOAA-16 AMSU.With these methods, weekly compositive snow-cover maps of China were achieved during the period of October 1, 2001 to April 1, 2002.The comparison of the ground snow-depth record from the meteorological stations all around the country with snowcover maps mapped by NOAA Interactive Snow and Ice Mapping System (IMS), and from SSM/I (Special Sensor Microw ave Imager) data w ere used to examine the reliability of the snow-cover maps form AMSU in detail.Analysis result shows that the discrimination of AMSU snow-cover maps is good, and the correctness of AMSU snow-cover maps is close or even superior to those of IMS and SSM/I, especially during the medium-term of the snow season.

LAND SURFACE TEMPERATURE ESTIMATED BY REMOTE SENSING DATA FROM FY-1D POLAR METEOROLOGICAL SATELLITE

Wu Xiao, Chen Weiying

2005, 16(1): 45-53.

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Abstract:
The split window method was widely used to retrieve the land surface temperature (LS T) from satellite remote sensing data in the 1980s and the 1990s.The scientists demonstrated theoretically or statistically that there exists a linear or non-linear relationship between the LST and AVHRR channel 4, 5 brightness temperatures.2818 clear sky radiosonde profiles were used to simulate the FY-1D HRPT channel 4, 5 brightness temperatures for different ground emissivities.The derived no n-linear regression equation for each ground type is :T_LS=T₄ +A(T₄-T₅)+B(T₄-T₅)² +D.Meanwhile, the calculating method of LST by using FY-1D HRPT data and the regression equation were described.Finally, the accuracy of the calculated LST in main land of China was given :compared with the 0 cm soil temperatures observed by Chinese meteorological ground stations, the LSTs calculated by FY-1D data are very co-ordinate with the station observations.For most ground stations, the deviations between the satellite LST and stations observations are less than 3.0 K.

RELATIONSHIP BETWEEN GPS PRECIPITABLE WATER VAPOR AND PRECIPITATION

Cao Yunchang, Fang Zongyi, Xia Qing

2005, 16(1): 54-59.

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Abstract:
Previous study shows that GPS precipitable water vapor (PWV) and local precipitation have close relationship.Observation of 2002 Anhui province and 2000 Beijing experiment shows that 2-hour increment of GPS PWV and local precipitation have good relationship. The correlation coefficient in mountain area is about 70 %, larger than that in plain area. Rainfall occurs in 4 hours after the rapid increase of PWV.The maximum hourly rainfall is proportion to the PWV increment.

ANALYSES OF AN ABRUPT HEAVY RAINSTORM IN FUPINGON JUNE 8, 2002

Liu Yong, Zhang Kexiang

2005, 16(1): 60-69.

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Abstract:
Systematically analyses were carried out for an abrupt heavy rainstorm in Fuping of Shaanxi province on June 8, 2002.The results show that a meso-scale shear line lying in front of 500 hPa trough is the meso-α-scale system that causes the rainstorm.Southeast jet outside typhoon named Coon located in the ocean surface on the east of Taiwan, extended to Shaanxi province from the sea, and supplied the moisture for the rainstorm.The Huabei anti-cyclonic ridge blocked off the eastward movement of rainstorm from the Qinghai-Xizang Plateau and slowed the local rainstorm.Jet sub-circulation supplied a continuous and powerful updraft.In the low-level wind field, two meso-β-scale cyclones were stable and still, and corresponding to the surface heavy rainfall center.On the infrared images, meso-β-scale convective cloud clusters were like an ellipse.The brightness temperature in the cloud top ranged from-60 to-70 ℃.The strength variation of meso-scale convective cloud clusters is largely related to the strength of sub-circulation.

DOPPLER RADAR ECHO FEATURE AND ENVIRONMENTAL CONDITION ANALYSIS OF A MESOSCALE RAIN BELT

Zhang Tengfei, Zhang Jie, Guo Rongfen

2005, 16(1): 70-77.

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Abstract:
By using a single 3830-CC Doppler intensive weather radar data and Micaps objective data, a mesoscale NNE-SSW band echo evolution and environmental condition under southsouthw est air stream around subtropical high were analyzed on August 22, 2002.The results show that the mesoscale band echo is a direct influential system of the mesoscale rain belt and that a warm shear of wind, south-southwest jet flow and anti-wind zone are major radar echo features of the severe precipitation.The south-southwest air stream around subtropical high of fers not only moisture condition, but also heat and dynamical conditions, which are indicated by moist potential vorticity distribution.The band echo and rain belt locate in the zone between barotropic instability and baroclinic stability with a potential instability of negative vorticity circulation in the lower layer.

EXPERIMENTS OF SHORT-RANGE ENSEMBLE PRECIPITATION PROBABILITY FORECASTS

Wang Chenxi

2005, 16(1): 78-88.

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Abstract:
In order to obtain useful information and create probability forecasts from ensemble, experiments of short-range ensemble precipitation probability forecasts are made for 22 precipitation cases from November 2001 to May 2002. The ensemble is created by using MM5 model configuration with different model physical process parameterization schemes and identical initial conditions. There are 8 ensemble members. Precipitation probability forecasts are created from the ensemble by using the methods of "Average", "Correlation" and "Rank". Calculations of ranked probability score (RPS), Brier score (BS) and relative operating characteristic (ROC) indicate that, for the synthetic effect of all precipitation categories' probability forecasts, "Rank" is much better than "Correlation" and "Average", and "Correlation" is almost same as "Average". For the average effect of every precipitation category's probability forecasts, "Rank" is also the best among the three methods, and "Correlation" is same as "Average". The average BS difference between "Rank" and "Average" is large and the average ROC square difference between the two methods is small. Averagely, the three methods' probability forecasts are all skillful for all precipitation categories. The skill of probability forecast for small precipitation category is higher than the skill large precipitation category.

A CIRCULATION SIGNAL OF ABNORMAL SNOW COVER OVER THE TIBETAN PLATEAU AND ITS RELATION TO SUMMER RAINFALL IN CHINA

Cai Xuezhan, Wu Bin

2005, 16(1): 89-95.

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Abstract:
Based on the integrated analysis for 1955—1993 snow cover data on the Tibetan Plateau and the NCEP/NCAR reanalyzed Northern Hemisphere 500 hPa geopotential height data, comparison and correlation analysis were performed. It reveals that there is a atmospheric teleconnection pattern during snowcover anomaly over the Plateau in winter, so abnormal snowcover teleconnection pattern intensity index (I_asp) is given. Results further reveal the possible association with East Asia-Pacific summer teleconnection patter and its impact on the rainy season rainbelt distribution in China, especially on rainfall over the middle and lower reaches of Yangtze River Valley. The result provides a physical base for the application of Iasp in show-term climate prediction.

VARIANCE OF INTERDECADAL COMPONENTOF GLOBAL SEA SURFACE TEMPERATURE ANOMALY AND THE CORRELATIONS TO THE CLIMATE OF CHINA

Zhou Xiaoxia, Wang Panxing, Zhu Changhan, Qin Jun

2005, 16(1): 96-104.

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Abstract:
The interdecadal and interannual components of global sea surface temperature anomaly (SSTA) were obtained by periodical analysis, and their significant variations over different areas of global sea and seasonal change were displayed by variance analysis. Then using singular value decomposition (SVD), the simultaneous and time-lag correlations of interdecadal sea surface anomaly and winter temperature/summer rainfall of China were investigated. Results show that the interdecadal SSTA is more evident than the interannual one both in winter and summer, and positive SSTA is usually assotiated with positive winter temperature anomaly in North China and positive rainfall anomaly in the Changjiang valley and South China, but negative rainfall anomaly in North China, and vice versa.

CONTRAST ANALYSIS OF THE INTERDECADAL VARIATION OF THE RELATION AMONG THE WESTERN PACIFIC/THE SOUTHERN OSCILLATION AND THE WINTER CLIMATE ANOMALIES IN CHINA

Li Chunhui, Guan Zhaoyong, He Jinhai, Liang Jianyin

2005, 16(1): 105-113.

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Abstract:
Using NCEP/NCAP reanalysis data, SST data set of GISST2. 3b, South Oscillation Index (SOI) of CRU as well as the surface air temperature/rainfall records from 160 stations in China, the relation among the western Pacific SST index, the southern oscillation index and the surface air temperature/rainfall in China in winter is investigated. Results indicate that, the relationship between WPI and SOI shows obvious inter-decadal changes in the winter during recent fifty years. When the correlation between WPI and SOI is weak and the western pacific SST warmer (colder), there exists anticyclone (cyclone) circulation at the lower troposphere over northern equatorial western pacific, which is not in favor maintaining a close correlation between the West pacific SST and ENSO. Accordingly, through the whole troposphere, such system Presents quasi-barotropic structure in the winter. Furthermore, when the correlation between WPI and SOI is strong (weak or reversed), the correlation between WPI and the surface air temperature/rainfall in China is weak (strong) in the winter.

THE RESEARCH OF METEOROLOGICAL METADATA STANDARD AND INFORMATION ISSUING

Wang Guofu, Xu Feng, Wu Zeng xiang

2005, 16(1): 114-120.

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Abstract:
Metadata is making an important effect on the data exchange, information search in Web and sharing system design. The up-to-date development of metadata and metadata standards is introduced concisely. The establish principle, gist and content of our metadata standard are emphasized. The architecture and flow of metadata system are explored. At last, based on the layout and developing practice of "Meteorological Data Sharing Project", the blue print and implement of metadata issuing system for the China Meteorological Data Service Network are expounded in detail.

IMPLEMENTATION OF MATRICES-MULTIPLICATION ON SUPERCOMPUTER

Wu Xiang jun, Huang Liping

2005, 16(1): 121-128.

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Abstract:
The matrices multiplication is often used in NWP. On distributed systems, such as IBM-SP, the multiplication of two matrices requires data transpose and the efficient data communication are crucial to its performance. Two parallel algorithms are presented, one is based on column-row decomposition and another is based on mesh partition, and the implementation and communication-time of this two different methods are discussed. Results on IBM-SP show that the communication in mesh algorithm are less and the improvement on speedup is up to 10%.

Vol.16, NO.1, 2005