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Subseasonal features of the Asian summer monsoon in the NCEP climate forecast system

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Acta Oceanologica Sinica 2008年第3期27卷 88-103页

作者： Song YANG WEN Min R Wayne HIGGINS NOAA＇s Climate Prediction center Camp Springs Maryland 20746 USA Chinese Academy of meteorological Sciences Beijing 100081 China

The operational climate forecast system （CFS） of the US national centers for Environmental Prediction provides climate predictions over the world, and CFS products are becoming an important source of information for regional climate predictions in many Asian countries where monsoon climate dominates. Recent studies have shown that, on monthly-to-seasonal time-scales, the CFS is highly skillful in simulating and predicting the variability of the Asian monsoon. The higher-frequency variability of the Asian summer monsoon in the CFS is analyzed, using output from a version with a spectral triangular truncation of 126 waves in horizontal and 64 sigma layers in vertical, focusing on synoptic, quasi-biweekly, and intraseasonal time-scales. The onset processes of different regional monsoon components were investigated within Asia. Although the CFS generally overestimates variability of monsoon on these time-scales, it successfully captures many major features of the variance patterns, especially for the synoptic timescale. The CFS also captures the timing of summer monsoon onsets over India and the Indo-china Peninsula. However, it encounters difficulties in simulating the onset of the South china Sea monsoon. The success and failure of the CFS in simulating the onset of monsoon precipitation can also be seen from the associated features of simulated atmospheric circulation processes. Overall, the CFS is capable of simulating the synoptic-to-intraseasonal variability of the Asian summer monsoon with skills. As for seasonal-tointerannual time-scales shown previously, the model is expected to possess a potential for skillful predictions of the high-frequency variability of the Asian monsoon.

关键词： Asian summer monsoon onset evolution synoptic-to-intraseasonal variability NCEP climate prediction system

Approximate Solution of the Nonlinear Parallel Diffusion Theory of Charged Particles

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Approximate Solution of the Nonlinear Parallel Diffusion The...

第十四届全国日地空间物理学术研讨会

作者： Yu-Ting Zhu1 Gang Qin2 Gui Ming Le3 (1 Chinese Academy of meteorological Science, beijing 100081 ) (2 national Space Science center, beijing 100190 ) (3 national center for Space Weather, china meteorological administration, beijing 100081 )

Charged particles’ diffusion mechanism is one of outstanding problem in the astrophysics. Recently, Matthaeus et al. （ApJ 2003） developed a nonlinear guiding center theory （NLGC） of perpendicular diffusion of charged energetic particles with parallel diffusion coefficient as an input, which agrees with numerical simulations. In addition, Qin （ApJ 2007） developed a nonlinear parallel diffusion theory （NLPA） which if combined with NLGC could be used to solve parallel and perpendicular diffusion simultaneously. However, both of the NLGC and NLPA are in the forms of integral equation and not easy to be adopted in cosmic ray transport models. So that Zank et al. （JGR 2004） provided an approximate solution of NLGC. The solution agrees with the exact solution of the NLGC results very well. In this work we will adopt the similar method from Zank et al. （2004）to approximately solve the NLPA （Qin 2007） so that the solution of both parallel and perpendicular nonlinear diffusion coefficients can be included in numerical codes for cosmic rays transport simultaneously.

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Effect of non-spherical dust aerosol on its direct radiative forcing

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Effect of non-spherical dust aerosol on its direct radiative...

强化科技基础推进气象现代化——第29届中国气象学会年会

作者： Zhili Wang a,Hua Zhang b,Xianwen Jing a,b,Xiaodong Wei c a Chinese Academy of meteorological Sciences,beijing 100081,china b Laboratory for Climate Studies,national Climate center,china meteorological administration,beijing 100081,china c meteorological center,East china Bureau of Air Control,Shanghai 201702,china

The optical properties of spherical and non-spherical dust aerosols are calculated using the Lorenz-Mie theory and the combination of T-matrix method and an improved geometric optics *** resulting optical properties are then applied in an interactive system that coupled a general circulation model with an aerosol model to quantitatively analyze the effect of non-spherical dust aerosol on its direct radiative forcing(DRF).Our results show that the maximum difference in dust instantaneous radiative forcing(IRF) between spherical and non-spherical particles is 0.27 W m-2 at the top of the atmosphere(TOA) and appears over the Sahara Desert due to enhanced absorption of solar radiation by non-spherical *** global annual means of shortwave(longwave) IRFs due to spherical and non-spherical dust aerosols at the TOA for all sky are-0.62(0.074) W m-2 and-0.61(0.073) W m-2,respectively,and the corresponding values for clear sky are-1.16(0.092) W m-2 and-1.14(0.093) W m-2,which indicates that the non-spherical effect of dust has almost no effect on their global annual mean ***,non-spherical dust displays more evident influences than above on its atmospheric-and land-temperature adjusted radiative forcing(ARF) at the TOA over the Saharan Desert,West Asia,and northern china,with an approximate maximum increase of 3.0 and decrease of 0.5 W *** global annual means of shortwave(longwave) ARFs due to spherical and non-spherical dust aerosols are-0.55(0.052) W m-2 and-0.48(0.049) W m-2 at the TOA for all sky,respectively,and the corresponding values for clear sky are-1.07(0.066) W m-2 and-0.95(0.062) W *** ARFs of dust become much weaker than their corresponding *** absolute values of annual mean ARF for non-spherical dust are approximately 13%(11.2%) and 6%(6%) less than those of spherical dust for the shortwave and longwave for all sky(clear sky),*** results indicate that the non-spherical effect of dust can reduce their ARFs more obvio

关键词： Dust Spherical/Non-spherical Particles IRF ARF

Impact of the ENSO-related Tropical Pacific SST Anomalies on the Precipitation in china

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Impact of the ENSO-related Tropical Pacific SST Anomalies on...

中国气象学会2004年年会

作者： Wu Tongwen~1 Wu guoxiong~2 (1 national Climate center, china meteorological administration, beijing 100081 2 LASG, Institute of Atmospheric Physics, Chinese Academy of Sciences, beijing 100029)

＜正＞This paper describes an investigation of the seasonality and quasi-stationary feature of precipitation variation in china associated with the tropical Pacific sea surface temperature （SST）. The correlation analysis of precipitation anomalies with respect to an objective ENSO index shows that drought conditions prevail in northern china and excessive rains occur in southern china in seasons of the warm phase of ENSO, namely with positive SST anomalies in the equatorial eastern Pacific, and opposite anomalies of precipitation in the cold phase of ENSO. The ENSO-related precipitation variation in the Yangtze River Valley （central china） has some uncertainty.

关键词： Tropical Pacific SST anomalies/Precipitation in china/Influence

A new type of Shipboard meteorological satellite Receiving-processing System

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Acta Oceanologica Sinica 2000年第1期19卷 35-46页

作者： Xie Simei Hao Chunjiang Zou Bin Jing Qiyi Liao Xiaohong Sheng Xiaowen Zhang Canrong (1. national Research center for Marine Environment Forecasts, beijing 100081, china 2, Second Institute of china Aerospace Corporation 3. beijing Chuanyi Electric Compan Natl. Res. Ctr. Mar. Environ. F. Beijing 100081 China Second Inst. of china Aerosp. Corp. China beijing Chuanyi Electric Company Chinese Academy of Sciences Beijing China

The Shipboard meteorological satellite Receiving-processing System (SMSRPS) is specially developed for the navigation meteorological safeguard of the Antarctic exploration ship over the sea ice area of the forth Ocean. This system can suit to the climate environment of very high temperature high moisture and very low temperature - supersaturation; it has a self-protection ability to against the hurricane - force wind over force 12 and the strong vibration during icebreaking, as well as strong magnetic disturbance. It has two sets of receiving-imagery processing systems for polar orbit low-resolution and quasi-stationary high-solution satellites. The key creation Points of this system are as follows: 1. the active gyro-control stabilization platform and a mixed mounting system of three rotating a - B and x -- y axes are used. It solved the tracing difficulties both in the low elevation angle and very high elevation angle of polar-orbit satellite, even in the status of ship moving with continuously changing its poition, direction and ship roll and pitch. 2. Imagery processing subsystem. The newest BORLAND-- DELPHI language and PASCAL language pro gramming software are used under WINDOWS 95 environment. It has a dynamic positioning nested-grid system and electric mapping grid data system. It can show the latitude-longitude of any point on the map, and marks any object such as ship, station or island, and draws the route. It can monitor cloud and temperature, forest fire, anomalous change of ocean and land. It can output satellite cloud maps of 24 bit with very high clarity. This system is very advanced in technique for the whole structure with the features of small volume, light weight and very low cost. It suits to very bad climate and ocean environment. Its imagery process ing system has complete functions with high resolution and being very easy to operate. It is not only suit to land use, but also and specially to all kinds of ship over the sea. It can be exte

关键词： Shipboard meteorological satellite Receiving-processing System imagery processing system active gyro-control platform

THEORETICAL ANALYSES AND NUMERICAL EXPERIMENTS FOR TWO-DIMENSIONAL WIND RETRIEVALS FROM SINGLE-DOPPLER DATA

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Journal of Hydrodynamics 2010年第2期22卷 185-195页

作者： HUANG Si-xun CAO Xiao-qun DU Hua-dong ZHONG Ji-qin Institute of Meteorology PLA University of Science and Technology Nanjing 211101 China national University of Defense Technolog Changsha 410073 China Institute of Urban Meteorology China Meteorological Administration Beijing 100089 China

Based on variational adjoint methods,theoretical analyses and numerical experiments are performed for retrievals of two-dimensional winds and related parameters from single-Doppler radar data in polar *** the method,the reflectivity conservation equation is used as the governing equation and the mass continuity equation as a weak *** the same time,the stable functional of regularization and background field are also introduced in the cost *** on the ideal experiments with artificial data,real two-dimensional wind fields are retrieved with low-altitude data from the Nanjing Doppler Radar Station,and the results are encouraging and promising.

关键词： single-Doppler retrievals adjoint methods regularization methods two-dimensional wind

Operational retrieval of Asian sand and dust storm from FY-2C geostationary meteorological satellite and its application to real time forecast in Asia

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Operational retrieval of Asian sand and dust storm from FY-2...

“2010年北京气象学会中青年优秀论文评选”学术研讨会

作者： X.Q.Hu~(1,3),N.M.Lu~1,T.Niu~2,and P.Zhang~1 1 Key Laboratory of Radiometric Calibration and Validation for Environmental satellites(KLRCV),national satellite meteorological center,china meteorological administration(NSMC/CMA),beijing 100081,china 2 Centre for Atmosphere Watch & Services(CAWAS),Chinese Academy of meteorological Sciences,china meteorological administration(CMA),beijing 100081,china 3 Institute of remote sensing applications,Chinese Academy of Sciences,beijing 100101,china

This paper describes an operational retrieval algorithm for the sand/dust storm(SDS) from FY-2C/SVISSR (Stretched-Visible and Infrared Spin-Scan Radiometer) developed at the national satellite meteorological center (NSMC) of *** algorithm,called Dust Retrieval Algorithm based on Geostationary Imager(DRAGI), is based on the optical and radiative physical properties of SDS in mid-infrared and thermal infrared spectral regions as well as the observation of all bands in the geostationary imager, which include the Brightness Temperature Difference (BTD) in split window channels,Infrared Difference Dust Index(IDDI) and the ratio of middle infrared reflectance to visible *** also combines the visible and water vapor bands observation of the geostationary imager to identify the dust clouds from the surface targets and meteorological *** output product is validated by and related to other dust aerosol observations such as the synoptic weather reports,surface visibility,aerosol optical depth(AOD) and ground-based PM *** the SDS-IDD product and a data assimilation scheme,the dust forecast model CUACE/Dust achieved a substantial improvement to the SDS predictions in spring 2006.

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PLANNING OF THE SECOND GROUP meteorological NETWORKS OVER JIANG-HUAI PLAIN

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气象学报(英文版) 1988年第2期 187-195页

作者：杨贤为 national meteorological center State meteorological administration beijing

Based on the data of daily air temperature and relative humidity from 1961 to 1980 over the Jiang-Huai Plain,the structure functions of the two elements have been calculated,and thereby the relationshipsbetween error of linear interpolation and spacing of stations have been *** to the principle that the standard error of interpolation should not exceed the standard errorof observation,the maximum admissible spacings between stations of the second group meteorological net-works have been estimated over this ***,it has been found that replacing the interpolation along a segment by the interpolation in aplane will increase the accuracy of interpolation.

关键词： interpolation admissible spacing meteorological triangular OVER thereby JIANG devise utilizing

Assessment of Dust Aerosol Optical Depth and Shortwave Radiative Forcing over the Northwest Pacific Ocean in Spring Based on satellite Observations

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Atmospheric and Oceanic Science Letters 2009年第4期 223-228页

作者： CHEN Lin 1,2,SHI Guang-Yu 1,ZHONG Ling-Zhi 3,and TAN Sai-Chun 1 1 State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics,Institute of Atmospheric Physics,Chinese Academy of Sciences,beijing 100029,china 2 Key laboratory of Radiometric Calibration and Validation for Environmental satellites (KLRCV),national satellite Meteorology center,china meteorological administration (NSMC/CMA),beijing,100081,china 3 State Key Laboratory of Severe Weather,Chinese Academy of meteorological Sciences,beijing 100081,china State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical FluidDynamics Institute of Atmospheric Physics Chinese Academy of Sciences Beo＇ing 100029 China Key laboratory of Radiometric Calibration and Validation for Environmental satellites （KLRCV） National Satellite Meteorology center China Meteorological Administration （SMC/CMA） Beijing 100081 China State Key Laboratory of Severe Weather Chinese Academy of Meteorological Sciences Beijing 100081 China

Dust aerosol optical depth (AOD) and its ac-companying shortwave radiative forcing (RF) are usually simulated by numerical ***,by using 9 months of Moderate Resolution Imaging Spectroradiometer (MODIS) aerosol product data in combination with Clouds and the Earth’s Radiant Energy System Single Scanner Footprint (CERES/SSF) data,dust AOD and its shortwave RF were estimated over the cloud-free north-west (NW) Pacific Ocean in the springs of 2004,2005,and *** results showed that in this region,the mean dust AOD and its shortwave RF were 0.10 and 5.51 W m 2,*** order to validate the dust AOD de-rived by MODIS,results from the Goddard Global Ozone Chemistry Aerosol Radiation and Transport (GOCART) model were also used *** correlation coefficient between the monthly averaged dust AOD derived by MODIS measurements and the model simulation results was approximately *** the estimates of the dust AOD and its shortwave RF obtained in this study are based mainly on satellite data,they offer a good reference for numerical models.

关键词： dust aerosols optical depth shortwave radiative forcing northwest Pacific satellite measurements