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An integrative estimation model of summer rainfall-band patterns in china

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Progress in Natural Science:Materials International 2007年第3期17卷 280-288页

作者： WEI Fengying (state key {2. of {3. weather, chinese academy of meteorological Sciences, beijing 100081, china) state key {2. of {3. weather Chinese Academy of Meteorological Sciences Beijing 100081 China

Three variation indices are defined to objectively and quantitatively represent fluctuations of three rainfall-band patterns in summers in china for the period from 1951 to 2.05, and the variation features of these indices are analyzed on both of interdecadal and interannual scales. A new method is proposed to establish an integrative estimation model based on the analysis of rainfall-band indices, and the model is applied to air, ocean factors to estimate their roles on variations of three rainfall-band patterns on different time-scales. The tests of estimation effects show that the fluctuations of three rainfall-band patterns are composed of variations on both significant inter-decadal and interannual scales, of which the interannual variation is mainly influenced by the Elnino/Lanina events, the East Asia monsoon and the ridge locations of subtropical high pressures in western pacific, while the interdecadal variation is mainly controlled by the Pacific decadal oscillation and interdecadal oscillations of the Arctic oscillation, ENSO, Nino3.sea surface temperature and summer monsoon. The estimated results from the integrative estimation model of rainfall-band patterns suggest that the way of estimation first according to each time scale of both the interdecadal and interannual scales, then estimating with an integration, which is proposed in this paper, has an obvious improvement on that without separation of time scales.

关键词： rainfall-band pattern interannual variation interdecadal variation integration estimation model.

Interdecadal trend turning of global terrestrial temperature and precipitation during 1951-2.02

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Progress in Natural Science:Materials International 2008年第11期18卷 1383-1393页

作者： Xiaohui Shi Xiangde Xu state key {2. of {3. weather,chinese academy of meteorological Sciences,beijing 100081,china state key {2. of {3. weather Chinese Academy of Meteorological Sciences Beijing 100081 China

A grid-by-grid counting of interdecadal trend turning(ITT)of annual mean surface air temperature(SAT)and total precipitation at 67,3.9 terrestrial grids in the period 1951-2.02.is *** analysis of the last ITTs of SAT and total precipitation in the period,in the context of both occurrence time and linear trends after the breakpoint,indicates that a warming trend has become highly significant across most reagent of the world in the late 2.th *** terrestrial grids have recorded an ITT of total precipitation in either the 1970s or 1980s,and 45.7% of the terrestrial grids in the study have seen a decreasing trend in total annual precipitation after the break- point,with the remaining 54.3. having experienced an increasing ***,global terrestrial regions have experienced either an increasingly warm and dry climate or an increasingly warm and wet *** analysis of ITT of regional mean SAT and total pre- cipitation in 2. regions shows that the Northern American continent has become increasingly warm and dry after the last interdecadal ***,the African continent has become increasingly warm and wet,with both Europe and most of Asia having the same *** South America and the West of Australia have experienced an opposite trend in climate,becoming increasingly cold and wet.

关键词： Global terrene Surface air temperature Precipitation Interdecadal trend turning

Possible mechanism of the effect of convection over Asian-Australian “land bridge” on the East Asian summer monsoon onset

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Science china Earth Sciences 2006年第11期49卷 1223-1232页

作者： HE Jinhai1, WEN Min2. DING Yihui3.& ZHANG Renhe2.1. Jiangsu key {3. of {2. Disaster (KLME), Nanjing Institute of Meteorology, Nanjing University of Informa- tion Science and Technology, Nanjing 2.0044, china 2. state key laboratory of severe weather (LaSW), chinese academy of {2. Sciences, beijing 100081, china 3. National Climate Center, chinese {2. Administration, beijing 100081, china 1. Jiangsu key laboratory of {2. Disaster (KLME) Nanjing Institute of Meteorology Nanjing University of Information Science and Technology Nanjing 210044 China 2. state key laboratory of severe weather (LaSW) Chinese Academy of Meteorological Sciences Beijing 100081 China 3. National Climate Center Chinese Meteorological Administration Beijing 100081 China

The Asian-Australian “land bridge” is an area with the most vigorous convection in Asian monsoon region in boreal spring, where the onset and march of convection are well associated with the onset of East Asian summer monsoon. The convection occurs over Indo-china Peninsula as early as mid-April, which exerts critical impact on the evolution of monsoon circulation. Before mid-April there are primarily sensible heatings to the atmosphere over Indo-china Peninsula and Indian Peninsula, so the apparent heating ratios over them decrease with height. However, after mid-April it changes into latent heating over Indo-china Peninsula due to the onset of convection, and the apparent heating ratio increases with height in mid- and lower troposphere. The vertical distribution of heating ratio and its differences between Indo-china Peninsula and Indian Peninsula are the key factors leading to the splitting of boreal subtropical high belt over the Bay of Bengal. Such mechanism is strongly supported by the fact that the evolution of the vertical heating ratio gradient above Indo-china Peninsula leads that of 850 hPa vorticity over the Bay of Bengal. Convections over Indo-china Peninsula and its surrounding areas further increase after the splitting. Since then, there is a positive feedback lying among the convective heating, the eastward retreat of the subtropical high and the march of monsoon, which is a possible mechanism of the advance of summer monsoon and convection from Indo-china Peninsula to South china Sea.

关键词： Asian-Australian 'land bridge', tropical convection, Indo-china Peninsula, the splitting of boreal subtropical high belt, East Asian summer monsoon onset.

The least-square method in complex number domain

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Progress in Natural Science:Materials International 2006年第3期16卷 307-312页

作者： GU Xiangqian, KANG Hongwen and CAO Hongxing (state key {2. of {3. weather, chinese academy of meteorological Sciences, beijing 100081, china) [a]state key {2. of {3. weather Chinese Academy of Meteorological Sciences Beijing China

The classical least-square method was extended from the real number into the complex number domain, which is called the complex least-square method. The mathematical derivation and its applications show that the complex least-square method is different from one that the real number and the imaginary number are separately calculated with the classical least-square, by which the actual least-square estimation cannot be obtained in practice. Applications of this new method to an arbitrarily given series and to the precipitation in rainy season at 160 meteorological stations in china mainland show advantages of this method over other conventional statistical models.

关键词： complex least square Fourier transformation forecast in rainy season.

Urban effects and summer thunderstorms in a tropical cyclone affected situation over Guangzhou city

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Science china Earth Sciences 2007年第12期50卷 1867-1876页

作者： MENG WeiGuang1,3.YAN JingHua1 & HU HaiBo2.1 Institute of Tropical and Marine Meteorology,chinese meteorological Administration(CMA),Guangzhou 510080,{2. 2.Institute of Urban Meteorology,CMA,beijing 100089,{2. 3.state key laboratory of severe weather,chinese {13. of meteorological Sciences,beijing 100081,{2. 1. Institute of Tropical and Marine Meteorology Chinese Meteorological Administration (CMA) Guangzhou 510080 China 3. state key {2. of {3. weather Chinese Academy of Meteorological Sciences Beijing 100081 China 2. Institute of Urban Meteorology CMA Beijing 100089 China

With data mainly from Guangzhou mesonet Automatic weather Stations(AWS),Guangzhou Doppler Radar and satellite TBB data,characteristics and evolution of the urban heat island(UHI) over Guang-zhou City were analyzed in a tropical cyclone affected situation for early August *** particular,two thunderstorms occurring during this period respectively at the night of 4 August and in the afternoon of 7 August were investigated to study the relationships between the development of thunderstorms and the *** showed that two thunderstorms were associated with the UHI *** induced local air convergence and initiated the thunderstorm *** cases showed a general agreement in time and space for the locations of maximum UHI,convergence,convection,and *** was found to be more favorable to developing in time periods and locations with stronger intensity of *** also showed that,due to the urban effects,both thunderstorms got strengthened when moving over Guangzhou City,with maximum radar echoes observed right over the urban area and precipitation located within the *** these features reveal that two thunderstorms were urban-induced storms.

关键词： summer thunderstorms, urban heat islands (UHI), urban effects, tropical cyclone

Multiple time scale evaluation of the energy balance during the maize growing season,and a new reason for energy imbalance

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Science china Earth Sciences 2009年第1期52卷 108-117页

作者： GUO JianXia1,2.BIAN LinGen3.& DAI YongJiu2.1 meteorological Observation Center of{3. meteorological Administration,beijing 100081,china 2.state key laboratory of Remote Sensing Science,School of Geography and Remote Sensing Science,beijing Normal University,beijing 100875,china 3.{12. academy of meteorological Sciences,beijing 100081,china meteorological Observation Center of china meteorological Administration Beijing 100081 China state key {2. of Remote Sensing Science School of Geography and Remote Sensing Science Beijing Normal University Beijing 100875 China

Energy imbalance is a common problem associated with the measurement of surface energy using the eddy covariance *** the evaluation of the energy balance,people usually pay more attention to the statistical result that the effective energy(the sum of sensible and latent heat) is systematically lower than the available energy(the difference of net radiation and ground heat flux).However,little attention has been paid to the existence of the reversed situation when the effective energy is larger than the available energy or their contribution to the overall energy closure *** this paper,based on the analysis of the energy balance on multiple time scales across the maize growth season,we conclude that the non-synchronization of energy components is the main reason for the existence of the reversed *** shifting the phase of the effective energy components half an hour ahead,the rates of energy closure over all time scales are improved and dramatically reduce the number of the half-hourly samples when the energy ratio exceeds 1 or is below *** to the characteristics of the energy distribution and transformation over multiple time scales,latent heat is always the main type of energy cost,and the residual of the energy balance increases with the growth of the maize plant surpassing the sensible heat for seventy *** is suggested that the heat storage and photosynthetic energy play an important role in the energy balance during the growing period of maize.

关键词： maize energy balance multiple time scale energy hysteresis

Characteristics of climate change in the “significant impact zone” affected by aerosols over eastern china in warm seasons

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Science china Earth Sciences 2008年第5期51卷 730-739页

作者： SHI XiaoHui1, XU XiangDe1, XIE LiAn2.1 state key {2. of severe weather, chinese academy of meteorological Sciences, beijing 100081, china 2.Department of Marine, Earth and Atmospheric Sciences, North Carolina state University, Raleigh NC2.695-82.8, USA state key {2. of {3. weather Chinese Academy of Meteorological Sciences Beijing 100081 China Department of Marine Earth and Atmospheric Sciences North Carolina State University Raleigh NC 27695-8208 USA

Through analysis of the distribution pattern and changing characteristics of atmospheric aerosols over the East Asia region during warm seasons in recent 2. a and beyond as well as their possible interac- tive relationship with a variety of meteorological elements, it is found that the high-value zone of aerosol optical depth derived from the Total Ozone Mapping Spectrometer (TOMS), its significant negative correlation zones in terms of sunshine duration (SD) and surface air temperature (SAT) and its significant positive correlation zones with low-level cloud amount (LCC) are co-located in the South china region during warm periods. Based on this finding, the region is referred to as a "significant impact zone" (SI zone) affected by aerosols. Then, a comparative analysis is made on variation differ- ences of observed SAT, SD and LCC, etc. in different regions. It is also found that the LCC is increased and the SD is decreased within the "SI zone" over eastern china during the warm season. These characteristics are more evident than those beyond the zone, while the warming trend within the zone is evidently weaker than that outside it. Studies show that since recent 2. a, under the influence of aerosols, the LCC tend to increase substantially with a clear decrease of SD and an unnoticeable warming trend within the "SI zone". Comparing with the climate change beyond the zone, the difference is significant. Therefore, the effects of atmospheric aerosols on climate is possibly one of the contri- butions to the difference of climate change existed between the southern and northern parts of the Eastern china during a warm season.

关键词： warm season significant impact zone of aerosols climate change

A semi-implicit semi-Lagrangian global nonhydrostatic model and the polar discretization scheme

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Science china Earth Sciences 2007年第12期50卷 1885-1891页

作者： YANG XueSheng1,CHEN JiaBin2.HU JiangLin1,CHEN DeHui1,SHEN XueShun1,ZHANG HongLiang1 1 state key {2. of severe weather,chinese academy of meteorological Sciences,beijing 100081,china 2.state key {2. of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics,Institute of Atmospheric Physics,beijing 10002.,china 1. state key {2. of {3. weather Chinese Academy of Meteorological Sciences Beijing 100081 China 2. state key {2. of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric Physics Beijing 100029 China

The Global/Regional Assimilation and PrEdiction System(GRAPES) is a newly developed global non-hydrostatic numerical prediction model,which will become the next generation medium-range opera-tional model at china meteorological Administration(CMA).The dynamic framework of GRAPES is featuring with fully compressible equations,nonhydrostatic or hydrostatic optionally,two-level time semi-Lagrangian and semi-implicit time integration,Charney-Phillips vertical staggering,and complex three-dimensional pre-conditioned Helmholtz solver,*** the singularity of horizontal momentum equations at the poles,the polar discretization schemes are described,which include adoption of Arakawa C horizontal grid with ν at poles,incorporation of polar filtering to maintain the computational stability,the correction to Helmholtz equation near the poles,as well as the treatment of semi-Lagrangian interpolation to improve the departure point accuracy,*** balanced flow tests validate the rationality of the treatment of semi-Lagrangian departure point calculation and the polar discretization during long time *** and Suarez tests show that the conservation proper-ties of GRAPES model are quite good.

关键词： nonhydrostatic, global model, semi-implicit, semi-Lagrangian, polar discretization, conservation

Responses of soil respiration in non-growing seasons to environmental factors in a maize agroecosystem,Northeast china

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chinese Science Bulletin 2010年第24期55卷 2723-2730页

作者： LI RongPing1,2.3. ZHOU GuangSheng1,4 & WANG Yu1,3.1 state key {2. of Vegetation and Environmental Change, Institute of Botany, chinese academy of Sciences, beijing 100093. china 2.Institute of Atmospheric Environment, china meteorological Administration, Shenyang 110016, china 3.Graduate University of chinese academy of Sciences, beijing 100049, china 4 chinese academy of meteorological Sciences, beijing 100081, china state key {2. of Vegetation and Environmental Change Institute of Botany Chinese Academy of Sciences Beijing 100093 China Institute of Atmospheric Environment China Meteorological Administration Shenyang 110016 China Graduate University of chinese academy of Sciences Beijing 100049 China chinese academy of {2. Sciences Beijing 100081 China

Based on continuous three-year measurements (from 2.04 to 2.07) of eddy covariance and related environmental factors, environmental controls on variation in soil respiration (Rs) during non-growing season were explored in a maize agroecosystem in Northeast china. Our results indicated that during non-growing seasons, daily Rs was 1.08-4.08 g CO2.m-2.d-1, and the lowest occurred in late November. The average Rs of non-growing season was 456.06 ± 2..01 g CO2.m-2. accounting for 11% of the gross primary production (GPP) of the growing season. Additionally, at monthly scale, the lowest value of Rs appeared in January or February. From the beginning to the end of non-growing season, daily Rs tended to decrease first, and then increase to the highest. There was a significant quadratic curve relationship between Rs and soil temperature at 10 cm depth when soil temperature was more than 0°C (P3.%-70%. When soil water content was more than 0.1 m3.m-3. soil moisture at 10 cm depth was significantly parabolically correlated with Rs (P3.-79%. Meanwhile, the standard error of regression estimation between the values of prediction and observation for Rs could reach 2.7%-11.8%. Rs in non-growing season can account for 2..4% of Rs in growing season, indicating that it plays a critical role in assessing the carbon budget in maize agroecosystem, Northeast china.

关键词：中国东北地区农田生态系统生长季节土壤呼吸环境因素玉米土壤含水量反应