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第七届亚洲气溶胶会议

作者： Lihong Ren 1 2 Wei Wang1 Jianhua Chen1 Hongjie Liu1 and Renjian Zhang21 Chinese Research Academy of Environmental Sciences Beijing Chaoyang district Dayangfang NO.8 Beijing 100012 2 institute of atmospheric physics Beijing Chaoyang district Qijiahuozi Beijing 100029

Aircraft measurements were carried out over eastern coastal areas of China in spring and winter of 2002, Yangtze River areas in summer of 2003 and spring of 2004 and Pearl River delta region in autumn of 2004, respectively. Eight ionic components of particulate matters were sampled by filters. In these experiments, nitrate, sulfate and ammonium were the main water-soluble components in particulate matters. The total fraction of SO42- and NH4+ accounted for over 60% in PM10 and PM2.5. Crustal species （K+, Ca2+ and Mg2+） had lower fractions （less than 5%）. These indicate that coal combustion pollution is the main pollution type in most regions of China. For latitudinal distribution, the concentrations of ionic species observed in northern regions were higher than those obtained in southern regions. It is due to the effects of coal burning for warming in winter and dust storm in spring in northern areas. For longitudinal distribution, the concentrations in south-western region were obviously lower than those in eastern region. Vertical distribution of ionic species showed a general decreasing trend with increasing flight altitude. For seasonal variation, the ionic species has lower concentration in summer due to wet deposit. Analysis of correlations between ionic species suggests that these components had the same source, i.e., they are mainly influenced by anthropogenic source. NH4+ and SO42- were strongly correlated, indicating that combustion was the dominant source, and they existed as （NH4）2SO4 and NH4HSO4. The depletion of Cl- was existed in air-suspended particles. The ratio of SO42- to NO3- is between 1.0 and 4.0, indicating particulate matters mainly come from emission of coal burning in China.

关键词： Aircraft measurements Ionic components Particulate matters China

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Input function and simulated distributions of tritium in the North Pacific

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Science China Earth Sciences 2010年第3期53卷 441-453页

作者： BA Qi1,2 & XU YongFu1 1 State Key Laboratory of atmospheric Boundary Layer physics and atmospheric Chemistry, institute of atmospheric physics, Chinese Academy of Sciences, Beijing 100029, China 2 Graduate University of Chinese Academy of Sciences, Beijing 100049, China 1. State Key Laboratory of atmospheric Boundary Layer physics and atmospheric Chemistry Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China

An ocean general circulation model (OGCM) of the North Pacific with a southern open boundary condition is used to simulate the distribution and transport of tritium in the North Pacific. First, the observed tritium in precipitation dataset of GNIP/ISOHIS is chosen, and used to develop an input function of tritium for the model domain from 1951 to 1997 in terms of the triangulation for interpolation. Then, the input function is used as an upper flux for the tritium model. The OGCM with tritium is integrated for 47 years with the initial condition of zero tritium concentrations. Compared with the observations from GEOSECS and WOCE, the model generates a meridional gradient of surface tritium concentrations and the high tritium concentrations in the subsurface layer, which is consistent with that indicated in the observations. The simulated time series of total tritium fluxes from the atmosphere to the ocean shows a spike in 1963. The total inventory of tritium in the ocean changes slowly with time after 1975. Tritium enters the higher-latitude region, and then is mainly transported by the subsurface process towards the equatorial region, which is well simulated in the model. However, the difference mainly occurs at 30°N–40°N, which can be seen also in the simulation of CFCs. This difference may partly originate from the insufficient description of physical processes in the OGCM. Nevertheless, some uncertainties exist in the development of the tritium input function, which can also influence the simulated results.

关键词： North Pacific basin-wide ocean general circulation model tritium input function tritium distributions

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Strengthening of the boreal winter Hadley circulation and its connection with ENSO

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Progress in Natural Science:Materials International 2007年第11期17卷 1327-1333页

作者： Ma Jie1,2 and Li Jianping2(1. College of atmospheric Sciences, Lanzhou University, Lanzhou 730000, China 2. LASG, institute of atmospheric physics, Chinese Academy of Sciences, Beijing 100029, China) College of atmospheric Sciences Lanzhou University Lanzhou 730000 China LASG Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

Empirical orthogonal function (EOF) analysis is carried out for the year-to-year variability of the boreal winter (DJF) mass stream function of the mean meridional circulation (MMC) during the period 1948—2005. The results demonstrate that it is dominated by the equatorially asymmetric and symmetric modes. Further analysis shows that the former mode is linked with the boreal winter Hadley cell mainly on the decadal time-scale, and the latter on the interannual time-scale. The asymmetric mode index (AMI) with a clear upward trend contributes to the decadal strengthening of the boreal Hadley circulation, and is closely correlated with the tropical SST warming, especially in the region of Indo-west Pacific warm pool (INWP). Furthermore, the AMI also contributes to the abrupt change of the correlation coefficient between the boreal Hadley circulation and ENSO after 1976. The symmetric mode index (SMI) with robust and stable linkage with ENSO shows a significant interannual variability, suggesting that the variability of the Hadley circulation is mainly associated with ENSO on the interannual time-scale.

关键词： the Hadley circulation interannual time-scale decadal time-scale

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Seasonal variation of global stratosphere-troposphere mass exchange

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Progress in Natural Science:Materials International 2007年第12期17卷 1466-1475页

作者： Guo Dong1,2, Lu Daren2 and Sun Zhaobo1(1. institute of atmospheric Sciences, Nanjing University of Information Science and Technology, Nanjing 210044, China 2. LAGEO, institute of atmospheric physics, Chinese Academy of Sciences, Beijing 100029, China) institute of atmospheric Sciences Nanjing University of Information Science and Technology Nanjing 210044 China LAGEO Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

By Wei formula in pressure coordinate, the stratosphere-troposphere mass exchange (STME) is diagnosed globally for 44 years from 1958 to 2001 using the European Center for Medium-Range Weather Forecasts (ECMWF) reanalysis datasets. Regions of mass flux into the stratosphere are found over Indonesia, bay of Bangladesh and the mid-west coast of South Africa. Compensating mass outflow from the stratosphere appears mainly over mid-latitudes near large-scale troughs. Upward and downward transport of mass at the middle and high latitudes accompany with each other. Mass flux into troposphere is stronger in autumn and winter than in spring and summer. Strong downward mass flux into the troposphere occurs in eastern Asia the whole year with nearly stable sites. Although the area of eastern Asia accounts for only 5.6% of that of the northern hemisphere (NH), its net mass exchange reaches 15.83% of that of the NH, which means that research on STME of eastern Asia is greatly important to that of the NH and even the global areas. Air across the tropopause enters more from stratosphere to troposphere than that from troposphere to stratosphere, which is possibly related with systematic bias of the assimilated datasets and with persistent rise of the tropopause height. Contributions of the mass exchange and the mass flux exchange in the NH and southern hemisphere (SH) on their latitudes increase from equator to pole, with larger contributions in the NH. Mass exchange and mass flux exchange per areas at high latitudes are larger than that at low latitudes, which means greater mass exchange efficiency at high latitudes.

关键词： stratosphere troposphere mass exchange seasonal variation.

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The mechanism of the effects of the upwelling mean on the ENSO event mature phase locking

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Science China Earth Sciences 2007年第8期50卷 1266-1272页

作者： YAN BangLiang CMSR, institute of atmospheric physics, Chinese Academy of Sciences, Beijing 100029, China 1. CMSR Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

The mechanism of the effects of the upwelling mean on the ENSO event mature phase locking is ex-amined by using a mixed-mode model. The results show that the positive feedback process of the ef-fects of the seasonal variation of the upwelling mean on the Kelvin wave is the mechanism of the locking of the event mature phase to the end of the calendar year. The memory of the Rossby waves for the sign-shifting of the sea surface temperature anomaly from positive to negative 6 months before the cold peak time is the other mechanism of the locking of the La Nia event mature phase to the end of the calendar year. The results here are different from previous ones which suggest that the balance between cold and warm trends of sea surface temperature anomaly is the mechanism involved. The cold trend is caused by the upwelling Kelvin wave from upwelling Rossby wave reflected at the western boundary, excited by the westerly anomaly stress over the central Pacific and amplified by the seasonal variation of the coupled strength in its way propagating westward. The warm trend is caused by the Kelvin wave forced by the western wind stress over the middle and eastern equatorial Pacific. The cause of the differences is due to the opposite phase of the seasonal variation of the upwelling mean to that in the observation and an improper parameterization scheme for the effects of the seasonal varia-tion of the upwelling mean on the ENSO cycle in previous studies.

关键词： Kelvin wave Rossby wave interaction between atmosphere and sea positive feedback

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Improved ENSO simulation in regional coupled GCM using regressive correction method

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Science China Earth Sciences 2007年第8期50卷 1258-1265页

作者： FU WeiWei1 & ZHOU GuangQing2 1 Nansen-Zhu International Research Center (NZC), institute of atmospheric physics, Chinese Academy of Sciences (CAS), Beijing 100029, China 2 State Key Laboratory of Numerical Modeling for atmospheric Sciences and Geophysical Fluid Dynamics (LASG), institute of At-mospheric physics, CAS, Beijing 100029, China 1. Nansen-Zhu International Research Center (NZC) Institute of Atmospheric Physics Chinese Academy of Sciences (CAS) Beijing 100029 China 2. State Key Laboratory of Numerical Modeling for atmospheric Sciences and Geophysical Fluid Dynamics (LASG) Institute of Atmospheric Physics CAS Beijing 100029 China

A regressive correction method is presented with the primary goal of improving ENSO simulation in regional coupled GCM. It focuses on the correction of ocean-atmosphere exchanged fluxes. On the basis of numerical experiments and analysis, the method can be described as follows: first, driving the ocean model with heat and momentum flux computed from a long-term observation data set; the pro-duced SST is then applied to force the AGCM as its boundary condition; after that the AGCM’s simula-tion and the corresponding observation can be correlated by a linear regressive formula. Thus the re-gressive correction coefficients for the simulation with spatial and temporal variation could be obtained by linear fitting. Finally the coefficients are applied to redressing the variables used for the calculation of the exchanged air-sea flux in the coupled model when it starts integration. This method together with the anomaly coupling method is tested in a regional coupled model, which is composed of a global grid-point atmospheric general circulation model and a high-resolution tropical Pacific Ocean model. The comparison of the results shows that it is superior to the anomaly coupling both in reducing the coupled model ‘climate drift’ and in improving the ENSO simulation in the tropical Pacific Ocean.

关键词： anomaly coupling regressive correction method regional coupled model ENSO simulation

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Nonlinear local Lyapunov exponent and atmospheric predictability research

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Science China Earth Sciences 2006年第10期49卷 1111-1120页

作者： CHEN Baohua1, LI Jianping1,2 & DING Ruiqiang2 1. College of atmospheric Sciences, Lanzhou University, Lanzhou 730000, China 2. State Key Laboratory of Numerical Modeling for atmospheric Science and Geophysical Fluid Dynamics (LASG), institute of atmospheric physics, Chinese Academy of Sciences, Beijing 100029, China 1. College of atmospheric Sciences Lanzhou University Lanzhou 730000 China 2. State Key Laboratory of Numerical Modeling for atmospheric Science and Geophysical Fluid Dynamics (LASG) Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

Because atmosphere itself is a nonlinear system and there exist some problems using the linearized equations to study the initial error growth, in this paper we try to use the error nonlinear growth theory to discuss its evolution, based on which we first put forward a new concept: nonlinear local Lyapunov exponent. It is quite different from the classic Lyapunov exponent because it may characterize the finite time error local average growth and its value depends on the initial condition, initial error, variables, evolution time, temporal and spatial scales. Based on its definition and the at-mospheric features, we provide a reasonable algorithm to the exponent for the experimental data, obtain the atmospheric initial error growth in finite time and gain the maximal prediction time. Lastly, taking 500 hPa height field as example, we discuss the application of the nonlinear local Lyapunov exponent in the study of atmospheric predictability and get some reliable results: atmospheric predictability has a distinct spatial structure. Overall, predictability shows a zonal distribution. Prediction time achieves the maximum over tropics, the second near the regions of Antarctic, it is also longer next to the Arctic and in subtropics and the mid-latitude the predictability is lowest. Particularly speaking, the average prediction time near the equation is 12 days and the maximum is located in the tropical Indian, Indonesia and the neighborhood, tropical eastern Pacific Ocean, on these regions the prediction time is about two weeks. Antarctic has a higher predictability than the neighboring latitudes and the prediction time is about 9 days. This feature is more obvious on Southern Hemispheric summer. In Arctic, the predictability is also higher than the one over mid-high latitudes but it is not pronounced as in Antarctic. Mid-high latitude of both Hemispheres (30°S―60°S, 30°―60°N) have the lowest predictability and the mean prediction time is just 3―4 d. In addition, predictab

关键词： nonlinear, local, Lyapunov exponent, atmospheric predictability, maximal prediction time.

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Influence of atmospheric heat sources over the Tibetan Plateau and the tropical western North Pacific on the inter-decadal variations of the stratosphere-troposphere exchange of water vapor

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Science China Earth Sciences 2008年第8期51卷 1179-1193页

作者： ZHAN RuiFen1,2&LI JianPing2 1Shanghai Typhoon institute of China Meteorological Administration,Shanghai 200030,China 2State Key Laboratory of Numerical Modeling for atmospheric Sciences and Geophysical Fluid Dynamics(LASG),institute of atmospheric physics,Chinese Academy of Sciences,Beijing 100029,China 1. Shanghai Typhoon institute of China Meteorological Administration Shanghai 200030 China 2. State Key Laboratory of Numerical Modeling for atmospheric Sciences and Geophysical Fluid Dynamics (LASG) Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

This study investigates the Stratosphere-Troposphere Exchange(STE) of water vapor,emphasizes its interdecadal variations over Asia in boreal summer,and discusses the influences of atmospheric heat sources over the Tibetan Plateau and the tropical western North Pacific(WNP) on them by using the Wei method with reanalysis data from the European Centre for Medium-Range Weather Forecasts(ECMWF) for the years of *** climatology shows that the upward transport of water vapor across the tropopause in boreal summer is the most robust over the joining area of the South Asian Peninsula and Indian-Pacific Oceans(defined as AIPO).The upward transport over there can persistently convey the abundant water vapor into the stratosphere and then influence the distribution and variation of the stratospheric water *** analysis shows that interdecadal variations of the water vapor exchange over the AIPO are significant,and its abrupt change occurred in the mid-1970s and the early *** these three periods,as important channels of the water vapor exchange,the effect of Bay of Bengal-East Asia as well as South China Sea was gradually weakening,while the role of the WNP becomes more and more *** studies show that atmospheric heat sources over the Tibetan Plateau and the WNP are two main factors in determining the interdecadal variations of water vapor *** thermal influences over the Tibetan Plateau and the WNP have been greatly adjusted over the pass 44 *** synthesis influences the interdecadal variations of the water vapor exchange by changing the Asian summer monsoon,but their roles vary with time and *** after 1992,the influence of heat source over the Tibetan Plateau remarkably weakens,while the heat source over the WNP dominates the across-tropopause water vapor *** have important implications for understanding the transport of other components in the atmosphere and estimating the impact of human activities(

关键词： Tibetan Plateau tropical western North Pacific atmospheric heat source STE inter-decadal variations

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Linear relationship between the interdecadal and interannual variabilities of North China rainfall in rainy season

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Chinese Science Bulletin 2003年第10期48卷 1040-1044页

作者： LU Riyu institute of atmospheric physics, Chinese Academy of Sciences, Beijing 100080, China institute of atmospheric physics Chinese Academy of Sciences Beijing 100080 China

Interdecadal and interannual timescales are dominant in the North China rainfall in rainy season (July and August). On the interdecadal timescale, the North China rainfall exhibited an abrupt decrease at the end of 1970s. In this study, we examined the effect of this abrupt rainfall decrease on the association between rainfall and circulation on the interannual timescale, and found that the interdecadal variation does not change the physical mechanism responsible for the interannual variation of North China rainfall. There is a linear relationship between the interdecadal and interannual variabilities of North China rainfall in rainy season.

关键词：线性关系中国北部降雨量大气环流

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North Pacific sea ice cover, a predictor for the Western North Pacific typhoon frequency?

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Science China Earth Sciences 2007年第8期50卷 1251-1257页

作者： FAN Ke institute of atmospheric physics, Chinese Academy of Sciences, Beijing 100029, China Department of atmospheric Science, Yun-nan University, Kunming 650091, China 1. institute of atmospheric physics Chinese Academy of Sciences Beijing 100029 China 2. Department of atmospheric Science Yunnan University Kunming 650091 China

The relationship between the sea ice cover in the North Pacific and the typhoon frequency has been studied in this paper. It follows that the index for the sea ice cover in the North Pacific (ISA) both in December-January-February (DJF) and in March-April-May (MAM) is negatively correlated with annual typhoon number over the western North Pacific (TNWNP) during 1965―2004, with correlation coeffi-cients of -0.42 and -0.49 respectively (above 99% significant level). Large sea ice cover in the North Pacific tends to decrease TNWNP. Positive ISA (MAM) is associated with the tropical circulation and SST anomalies in the North Pacific, which may lead to unfavorable dynamic and thermal conditions for typhoon genesis over WNP from June to October (JJASO). The variability of the atmospheric circula-tion over the North Pacific, associated with the ISA anomaly in MAM is connected to the tropical at-mospheric circulation variability in MAM via the teleconnection wave train. Besides, as the tropical circulation has strong seasonal persistency from the MAM to JJASO, thus, the ISA in MAM-related variability of the tropical atmospheric circulation as well as the SST can affect the typhoon activity over the western North Pacific.

关键词： typhoon sea ice cover North Pacific teleconnection

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