TEMPERATURE, RAINFALL VARIATIONS AND THEIR ANOMALIES OVER CHINA UNDER THE COLD-WARM BACKGROUND IN THE 20TH CENTURY*

In this study,the climate trend of the annual average air temperature and total annual rainfall in China in the present century has been examined.It is noted that in the Northwest,the Northeast and North China the climate has become notably warmer this century but the rainfall trend has not been evident,mainly negative.In the 1980s China's rainfall and temperature showed noticeable regional features:warm and dry in North China,cold and dry in the Southwest,warm and wet in the Northeast,cold and wet in the middle-lower reaches of the Changjiang River.Besides,the four interdecadal climate change features and ranges of this century have been studied.It is found that on the scale of several decades there was considerably less rainfall in the most part of China in the warm background than in the cold background.The increase of temperature which started from the 1970s mainly happened in the Northwest and Northeast,while to the south of the Huanghe River the temperature increase did not even as great as in 1940s.The corresponding rainfall feature is that most areas experienced much less rainfall except the area to the south of the Huanghe River and over the Changjiang and Huaihe River basin.     

应用趋势分析建立蔡家营矿床的物性分布模式

在河北蔡家营铅锌银矿区有代表性的Ｖ矿带，选取了一条钻探剖面，作物性研究。采集了３１２块标本，测试了磁化率、剩余磁化强度及密度等物性参数；结合地面重磁测量，用趋势分析方法，建立该矿床物性分布模式为本区建立质－地球物理分布模型提供了物性依据。     

滇西北新生代以来地球动力学背景及其环境影响

新生代、特别是第四纪以来,滇西北地壳活动增强：山脉的构造隆升速率从全新世以前的０．３～１．７ｍｍ／ａ变为全新世以来的２～７．１ｍｍ／ａ;全新世盆地的构造沉降速率较更新世增长１～２个数量级;第四纪断裂（以红河断裂为例）错移速率不断加大;现代地壳应力值高,构造变形速度快,地震活动强度加剧,地热流异常明显。地壳活动性加剧将造成滇西北地势格局和山地地质灾害问题进一步恶化、湖泊加速收缩、区域稳定性降低等一系列环境问题,人类生存环境将更严酷。     

How to improve attribution of changes in drought and flood impacts

ABSTRACT

For the development of sustainable, efficient risk management strategies for the hydrological extremes of droughts and floods, it is essential to understand the temporal changes of impacts, and their respective causes and interactions. In particular, little is known about changes in vulnerability and their influence on drought and flood impacts. We present a fictitious dialogue between two experts, one in droughts and the other in floods, showing that the main obstacles to scientific advancement in this area are both a lack of data and a lack of commonly accepted approaches. The drought and flood experts “discuss” available data and methods and we suggest a complementary approach. This approach consists of collecting a large number of single or multiple paired-event case studies from catchments around the world, undertaking detailed analyses of changes in impacts and drivers, and carrying out a comparative analysis. The advantages of this approach are that it allows detailed context- and location-specific assessments based on the paired-event analyses, and reveals general, transferable conclusions based on the comparative analysis of various case studies. Additionally, it is quite flexible in terms of data and can accommodate differences between floods and droughts.     

2005年前东北地区地震趋势预测

从地震活动时间序列的自然节律和地震天文周期等方面,对2005年以前东北地区浅震和深震的趋势,作了分析和预测。经χ~2检验可知。东北浅震受18.6年周的月球升交点运动和22年周的太阳黑子磁场交变影响较显著。综合预测,第五活跃期的时段为:1995年—2005年,在南、中北区内,都将发生5级以上地震。在未来活跃期内,发生7级地震的可能性很小,但发生两次以上6级强震的可能性较大,且可能在中区和南区发生。东北深震没有明显的自然周期和天文周期。综合预测,6级以上深震未来活动时段为:1996年—2008年。     

蒙古五十年来旱涝变化和降水趋势的研究

本文利用蒙古２５个台站的５２年逐月降水量资料，研究了蒙古旱变化和降水趋势。结果表明：蒙古平均年降水量为２１６．１ｍｍ，分布由南向北增加，东西部少，中部多，南部和西部为干旱区，中部和东部为半干旱区，与我国干旱半干旱区是一个整体，降水主要集中在夏季；年降水量变率为１５．６％－３８．０％。蒙古旱涝都很频繁，旱的频率高于涝的频率，而大涝的频率是大旱的两倍。年降水量服从正态分布，并有准３年和１１－１４年周期     

一个简单的热带有限区资料四维同化方案

根据广州区域气象中心热带有限区数值天气预报的条件和特点,设计了一个简单可行的四维同化方案,并通过模式平行试验,详细地分析了该方案对分析和预报的改进情况,表明该方案可以得到一个较为平衡而又与模式大气状态近于协调一致的分析场,大大缩短了模式的Spin—up时间和减小了积分初期模式调整的幅度,从而改进了预报结果。这种改进在资料稀疏区比资料密集区要大得多。通过四维同化,模式的高度场预报、风场预报、质量场及总动能在积分过程中的演变等都得到了令人满意的改进。通过在同化过程中区别对待20°N以南的资料稀疏区及其以北的资料密集区,进一步使模式降水预报得到显著的改进。     

ASSESSMENT OF THE EFFECTIVE RANK OF A (CO)VARIANCE MATRIX: A NON-PARAMETRIC GOODNESS-OF-FIT TEST

Each eigenvector of the dispersion matrix[X]~T[X]was shown to be a partial predictor of the originaldata matrix [X],the sum of the predictions from the individual principal components being equal to theexpectance of [X].By comparing the distributions of the members of two neighbouring predictedmatrices,[X]_(1...i)and [X](1...i+1)(i.e.the sums of the first i and i+1 individual predictions respectively),it was shown that they should be indistinguishable provided that i is equal to or greater than the effectiverank of [X],and significantly different otherwise.This was confirmed by analysing the visible absorptionspectra of methyl orange and methyl red solutions as well as the Raman spectra of Na_2SO_4 and MgSO_4solutions.On the grounds of these findings,a non-parametric goodness-of-fit test for assessing theeffective rank of[X]was proposed which proved to be comparatively conservative and more robust thanmost currently used tests.     

几种平均海面模型的数字实现与比较

本文对计算平均海面的平均值法、抗差法、动态模型法和动态抗差模型法作了实测数据的计算与比较。研究表明，动态抗差模型不仅能削弱海面垂直异常的影响，而且能顾及海面动态效应，求出平均海面和海面的平均升降，优于其它方法。