亚洲地区沙尘和人为气溶胶的分布及气候效应

利用耦合气溶胶化学过程的高分辨率区域气候模式RegCM4,模拟研究了2000~2009年亚洲地区沙尘和3种人为气溶胶（硫酸盐、黑碳、有机碳）的时空分布和直接气候效应。结果表明,模拟的气溶胶光学厚度在沙尘源区附近较为准确,但在人为活动影响较大的地区偏小。4种气溶胶的综合作用引起大气层顶负的辐射强迫,从而造成了地表气温的下降。降水方面,冬夏2季气溶胶对模拟区域的影响都以降水减少为主,这与气溶胶增加大气稳定度,减少地表蒸发并产生了偏北风距平有关。沙尘和人为气溶胶各自都能引起气温的下降和降水的减少,2类气溶胶都能造成的偏北风距平对我国南方降水的减少有重要作用。在人类活动密集区,人为气溶胶引起的气候效应约占总的4种气溶胶气候效应的50%。     

SACOL黑碳和沙尘气溶胶辐射强迫分析

利用兰州大学半干旱气候与环境观测站(SACOL)的太阳光度计资料、AREONET气溶胶光学特性资料,采用辐射传输模式SBDART分析了SACOL典型日个例沙尘气溶胶和黑碳气溶胶的长、短波辐射强迫,探讨了不同地表反照率和天顶角对气溶胶辐射强迫的影响.分析表明,沙尘和黑碳在地表的短波辐射强迫分别是-146.54,-60 W/m~2,长波辐射强迫分别是17.79,8.66 W/m~2,短波辐射强迫是长波的6倍多,沙尘辐射强迫是黑碳的2倍多;在大气层顶沙尘和黑碳短波辐射强迫是39.04,27.2 W/m~2,长波辐射强迫为12.19,5.0 W/m~2.短波辐射强迫随地表反照率的增加而增大,长波辐射强迫随地表反照率的增加线性减小.随天顶角减小,大气层顶的短波辐射强迫线性增加,地面短波辐射强迫对数减小,长波辐射强迫随天顶角的变化很小.     

东亚季风经向环流数值模拟及结果分析Ⅱ．模式性能检测及个例分析

局地径向环流诊断模式性能检验及对1994年5月1日世界时12时东亚季风区局地平均经向环流的模拟分析,分析所用的是经中科院大气物理研究所处理过的NCEP／NCAR再分析逐日资料,结果表明,在现行资料条件下模拟达到了预期的效果,证明该模式对局地经圆环流模拟性能良好,在此基础上,根据线性方程的叠加原理,进一步诊断分析方程中强迫项对向环流所起的作用。对1994年5月1日世界时12时东亚季风区局地平均径向环流而言,模拟出的各项的作用与对天气实况进行理论上的定性分析结果是相吻合的,在东亚季风区的经向环流形成过程,温度平流及绝热加热的作用相当显著,非绝热加热的作用在本文中没有作确切地比较,因其计算受到水汽资料精度和各层辐射资料缺乏的限制,另外,对流中的云物理过程也暂时未加以考虑。     

Dust direct radiative effects on the earth-atmosphere system over east Asia: Early spring cooling and late spring warming

Focusing on three dust storms occurring in spring 2001,we developed a detailed aerosol parameterization scheme and integrated it in a radiative transfer model to characterize possible impacts of solar altitude angle on dust direct radiative effects over China desert regions and the North Pacific,using actual daily solar altitude angles.Increasing solar altitude angle from early spring (or winter) to late spring (or summer) leads to increase of positive clear sky radiative forcing,and decrease of negative radiative forcing due to dust aerosols at the top of the atmosphere.Because solar altitude angle increases from early to late spring,dust-clear sky radiative forcing may change from negative to positive at the top of atmosphere,showing a change from cooling to heating of the earth-atmosphere system over high-albedo deserts and nearby regions.Over low-albedo ocean negative clear sky radiative forcing by dust may decrease,suggesting a change from strong to weak cooling on the earth-atmosphere system.The impacts of solar altitude angle on cloudy sky radiative forcing due to dust are similar to those of clear sky.Impacts of low cloud on dust radiative forcing are the same as increasing surface albedo.This causes the transition of dust cooling effects into heating effects over deserts to occur earlier,and causes decrease of negative radiative forcing over the ocean and even cause a change from weak negative radiative forcing to weak positive forcing over local areas.Even in the same East Asian desert regions and nearby areas,the strength and sign of the radiative forcings depend on storm dates and thus solar altitude angle.The nearer to early spring (or winter) a dust storm occurs,the easier it leads to negative radiative forcing at the top of atmosphere,which indicates cooling effects on the earth-atmosphere system.In contrast,the nearer to late spring (or summer) a dust storm occurs,the easier it leads to positive radiative forcing at the top of atmosphere,showing heating effects.Over East Asian deserts and nearby regions,dust layers may be regarded as cooling sources in early spring (winter) and warming sources in late spring (summer).     

Dusty cloud radiative forcing derived from satellite data for middle latitude regions of East Asia

The dusty cloud radiative forcing over the middle latitude regions of East Asia was estimated by using the 2-year (July 2002?June 2004) data of collocated clouds and the Earth’s radiant energy system (CERES) scanner and moderate resolution imaging spectroradiometer (MODIS) from Aqua Edition 1B SSF (single scanner footprint). The dusty cloud is defined as the cloud in dust storm environment or dust contaminated clouds. For clouds growing in the presence of dust, the instantaneous short-wave (SW) forcing at the top of the atmosphere (TOA) is about -275.7 W/m² for cloud over dust (COD) region. The clouds developing in no-dust cloud (CLD) regions yield the most negative short-wave (SW) forcing (-311.0 W/m²), which is about 12.8% stronger than those in COD regions. For long-wave (LW) radiative forcing, the no-dust cloud (CLD) is around 102.8 W/m², which is 20% less than the LW forcing from COD regions. The instantaneous TOA net radiative forcing for the CLD region is about -208.2 W/m², which is 42.1% larger than the values of COD regions. The existence of dust aerosols under clouds significantly reduces the cooling effect of clouds.     

Preliminary results of a regional air-sea coupled model over East Asia

We have established a regional air-sea coupled model over East Asia and conducted a 20-year integration to evaluate its performance in reproducing the present climate. The coupled model consists of RegCM3 and HYCOM controlled by the OASIS3 coupler with resuolution of 60 km for the atmosphere and 33 km for the ocean, respectively. Unlike some other regional air-sea coupled models, a one-way nesting method is employed in the oceanic component and a heat flux adjustment for solar radiation is used to remove an about 2°C cold bias in SST. The primary analysis for this 20-year integration shows that the coupled model successfully reproduces the main features of the circulations over East Asia, both in the atmosphere and the ocean, including climatology, seasonal and interannual variations. Improvements are seen in the coupled model compared to the uncoupled one, especially in the simulation of precipitation, the most important element of the East Asian monsoon, although there are still obvious discrepancies that come mainly from the model components themselves. Further analyses show that the rainfall simulation benefits from the enhancements of the Northwest Pacific Subtropical High in summer, which leads to the improvement of the moisture flux simulation at the middle-lower atmospheric circulation. The results indicate that the regional air-sea coupled model is more suitable for the East Asia monsoon simulation.     

Chronology of environmental events over East Asia during the past 130 ka

In the transitional region between the Loess Plateau and deserts, 4 sections located respectively at Yuling, Hengshan, Dingbian and Huining of China are studied. The high-resolution paleoclimatic records obtained show that environmental events on varying time scales have happened over East Asia. These events are dated with the time scales established using the recently-developed approach of Automatic Orbital Tuning. This leads to the establishment of the chronology of the environmental events.     

夏季青藏高原与东亚及热带的降水廓线差异分析

利用热带测雨卫星上测雨雷达的探测结果,考察了青藏高原与东亚及热带地区降水廓线的异同.结果表明高原深厚弱对流降水为高原上最主要的降水类型,占降水总样本近90%,而对总降水量的贡献超过70%,其雨顶高度接近海拔13 km,最大降水率出现在近地面.高原与陆面(非高原地区)及洋面的降水廓线差异主要表现在:①高原上缺少陆面和洋面上的层云降水;②高原深厚对流降水云团在垂直方向上只有2层,难以从平均廓线中辨认深厚降水云团中的冰水混合层和冰晶过冷水层;③高原深厚强对流降水在垂直方向的厚度受到了"压缩",平均最大厚度约10 km,显著小于陆面及洋面地区的平均厚度;④高原深厚弱对流降水平均廓线斜率大于其他地区对流降水平均廓线斜率,表明8 km以上的降水率垂直变率大,由此将释放出更多的潜热,造成显著高于周边地区的对中高层大气的加热.     

亚洲东部的泥盆系

亚洲东部的泥盆系按其发育历史和分布,大致可以分成相对稳定的大陆大区和相对活动的陆间大区两类。亚洲东部共分成7大区(其中3个为大陆大区,4个为陆间大区)、13区、46分区、125小区。 泥盆纪亚洲东部有西伯利亚、华北—塔里木、印度、哈萨克斯坦、华南等大小不等、活动性质各异的13个古板块,当时它们当中的大多数板块都分布于赤道两侧的中、低纬度地区。 亚洲东部泥盆纪有6个古动物地理区,每一个区都与赤道暖流的不同分支相连系,但它们均同属于一个老世界域。 本文还分别对各个板块泥盆纪古地理的演化和10个全球性生物事件作了概要的阐述.     

Features of tropical cyclone landfalls over East Asia corresponding to three types of Pacific warming decaying phase

This study examines the tropical cyclone （TC） landfall activities over the East Asia in three types of decaying phase of warm sea surface temperature anomalies （SSTAs） over the equatorial central-eastern Pacific： eastern Pacific warming decaying to La Nifia, eastern Pacific warming decaying to a neutral E1 Nifio-Southern Oscilla- tion phase, and a central Pacific warming decaying year. Results show that, for the type of eastern Pacific wanning decaying to La Nifia, more TCs make landfall over Hainan Island and Beibu Gulf, whereas fewer TCs reach eastern China coast. In particular, the number of landfalling TCs remarkably decreases in the decaying phase of eastern Pacific E1 Nifio to a neutral year. During the decaying phase of central Pacific E1 Nifio events, more TCs tend to make landfall over southern China, Indochina Peninsula and the Philippines. The anomalies of atmospheric circu- lation and environmental conditions induced by the SSTAs over the tropical Pacific in the different decaying types are responsible for the evident variation in features of TC landfall.     

东亚季风的活动规律及其与南亚季风的区别

讨论了东亚季风活动的一般特征、东亚季风的变异性及其原因探讨的途径、东亚季风和南亚季风的区别。     

东亚低纬地区大气臭氧时空分布特征

利用1979～1992年和1997～2008年2个时间段(分别称为Ⅰ期和Ⅱ期)的TOMS臭氧总量月平均网格资料,对东亚低纬地区大气臭氧的分布变化和纬度带特征进行了较为详细的对比研究.结果表明:①Ⅱ期较Ⅰ期区域大气臭氧浓度水平整体降低;区域臭氧浓度普遍低于同纬度其它区域,受地形和环流影响显著;②Ⅰ期和Ⅱ期区域平均及纬带平均臭氧浓度均表现为不同的季节和年际变化特征,南北有别,近赤道纬带和较高纬带有异;③Ⅰ期和Ⅱ期区域平均臭氧浓度时间序列除典型的年变化周期外,还有略低于QBO振荡的1.3～2.3a主周期,而区域赤道纬度带臭氧浓度QBO振荡却特别明显.值得注意的是,该1.3～2.3a主周期呈现区域南北半球部分的跷跷板式强弱振荡.     

1979-2011年东亚地区大气臭氧层变化趋势分析

 采用1979—2011年欧洲中期天气预报中心（ECMWF）的ERA-Interim的臭氧总量资料和分层资料,利用气候倾向率、Mann-Kendall检验等方法,分析了东亚地区臭氧总量及对流层、平流层臭氧的变化趋势.研究结果表明：①1979—2011年东亚地区臭氧总量总体来看呈现下降趋势.进一步将所考时段分为2期来看,臭氧总量在II期(1994—2011)稍有上升趋势,但尚未达到Ⅰ期(1979—1993)的平均臭氧总量水平,故认为东亚地区臭氧总量在21世纪初的恢复尚不明显;②东亚臭氧总量33年中的突变点是1984年,显著下降时间是1986年以后;③对东亚对流层-平流层的4个代表层的研究发现,4个层次的臭氧质量分数年际变化均呈下降趋势,其中臭氧质量分数下降速率最快的层次是10hPa,从低层到高层,臭氧质量分数的下降速率呈现“快-慢-快”的变化特点.     

东亚传统文化有利于现代文明发展

以中国古代传统文化为桉心的东亚传统文化至今在全世界仍有着广泛的影响。不过,在西方甚至在东亚,很多人认为这种文化是一种落后的文化,不利于社会和科技的发展,是与现代文明背道而驰的,现代文明就是西方文明。对于这种观点,参加今年8月在北京举行的中韩“东亚传统文化与现代文明”研讨会的专家给予了坚决反击。在这次会议上,记者采访了两家主办单位中国“天地生人”讲座的负责人宋正海和韩国东洋社会思想学会会长崔锡万。     

民间对日索赔与东亚和谐

亚洲民间对日索赔,是亚洲各国日本侵略战争的受害者及其遗属,以法律为武器、通过诉讼的方式要求加害方承担战争责任并进行谢罪赔偿的正义行动。日本政府顽固地拒绝向受害者进行道歉和赔偿,不仅与其追求的"正常国家"的目标背道而驰,还把其降为政治上的二流国家。在对日索赔过程中,亚洲正义和友好人士的积极合作,已经成为民间外交的重要组成部分。日本只有妥善解决战争受害者的赔偿问题,与受害民族达成谅解与和解,才能促进东亚和谐社会的早日形成。     

Relationship between the atmospheric heat source over Tibetan Plateau and the heat source and general circulation over East Asia

On the basis of NCEP/NCAR version I daily reanalysis data from 1971 to 2000 and by the methods of inverse calculation, correlation analysis and comparative analysis, the influences of atmospheric heat source （AHS） over the Tibetan Plateau on the large-scale AHS and the general circulation in summer are studied in this paper. The results show that AHS over the plateau in summer may trigger a heat source wavetrain propagating northeastward along the coast from the East Asian continent and West Pacific to Bering Strait-Arctic or even North America. In addition, if AHS over the eastern plateau is intense, South Asian High moves to southeast and West Pacific subtropical high moves to southwest; on the contrary, if AHS over the eastern plateau is weak, South Asian High moves to northwest and West Pacific subtropical high moves to northeast. Therefore, South Asian High and West Pacific subtropical high move in the horizontally-opposite directions in terms of interannual variation, for which AHS over the eastern plateau seems to be thermodynamically responsible.     

东亚高空大气气溶胶的分布及沙尘输送特征研究

利用长达20 年的SAGEⅡ(stratospheric aerosol and gas experimentⅡ) 资料, 研究了东亚地区5.0 ～15.0 km 高空气溶胶多年时空分布特征和变化趋势, 并研究了东亚沙尘活动对高空及下游的气溶胶输送。发现东亚高空气溶胶水平分布呈现上中下3 层不同的分布特征, 下层 5. 0 ～8. 5 km 高值区对应气溶胶源区青藏高原和西北沙漠地区;中层 9. 0 ～10. 0 km 高值区对应温带气旋高发的中纬度地区;上层 10. 5 ～15. 0 km 表现为低纬气溶胶含量显著高于高纬地区。高空各层气溶胶的空间分布受天气系统的影响具有明显的季节变化。近10 年来东亚高空气溶胶呈减少趋势, 平均光学厚度约下降了0. 016。另外还发现沙尘活动与 5. 0 ～11. 5 km 范围内的气溶胶显著相关, 反映沙尘活动影响的高度范围可以达到整个对流层。定义沙尘暴高空影响指数, 用来分析东亚沙尘暴对下游地区的影响, 发现随着时间推移沙尘逐渐向东移动, 在约 12 天之后可以到达大西洋。     

东亚最大通用型望远镜即将初光

目前,东亚最大的通用型光学望远镜已安装完成,正在进行最后的调试,有望在2007年4月正式投入观测。该望远镜口径2.4m,位于我国云南省丽江市西南方的高美古,海拔3200m。高美古2.4m望远镜的建设历时5年,而选定台址则在1994年。中科院云南天文台的天文学家在选址的过程中,首先通过观察卫星云图和地震记录,选出晴天数多而地震少的区域,然后再进行实地勘察。他们要考察山头是否够大,更重要的是测试     

Preliminary study on LGM climate simulation and the diagnosis for East Asia

LGM climate study is a hot topic in international fields on global changes. Climate simulation in this study applies both common designs of 21 kaBP boundary conditions from the Paleoclimate Modeling Intercomparison Project (PMIP), including insolation, glaciation, sea surface temperature and atmospheric CO₂ concentration, and land surface conditions from Eurasia continent by compilation of geological evidence. The simulation outputs are in agreement with climate spatial patterns reconstructed by observation records. Sensitive experiment on land surface conditions shows that changes in vegetation would make significant impacts on temperature and precipitation. Particularly in the Tibetan Plateau, this change would increase in differences of winter and summer temperature, precipitation and P-E.     

Dust storm in Asia continent and its bio-environmental effects in the North Pacific： A case study of the strongest dust event in April, 2001 in central Asia

The iron hypothesis, first proposed by John Martin in 1990[1], suggests that some surface oceans such as North and Equatorial Pacific Oceans have high nutrient but low chlorophyll (HNLC). Thus iron coming from terrestrial dusts is the primary factor limit…