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181.
分海洋和陆地两种情况来讨论IAP/LASG全球海-陆-气耦合系统模式(GOAL)四个版本的结果,并与观测资料进行对比分析。一些重要的大气变量包括表面空气温度,海平面气压和降水率用来评估GOALS模式模拟当代气候和气候变率的能力。总的来说,GOALS模式的四个版本都能够合理地再现观测到的平均气候态和季节变化的主要特征。同时评估也揭示了模式的一些缺陷。可以清楚地看到模拟的全球平均海平面气压的主要误差是在陆地上。陆地上表面空气温度模拟偏高主要是由于陆面过程的影响。值得注意的是降水率模拟偏低主要是在海洋上,而中高纬的陆地降水在北半球冬天却比观测偏高。 通过模式不同版本之间的相互比较研究,可以发现模式中太阳辐射日变化物理过程的引入明显地改善了表面空气温度的模拟,尤其是在中低纬度的陆地上。太阳辐射日变化的引入对热带陆地的降水和中高纬度的冬季降水也有较大改进。而且,由于使用了逐日通量距平交换方案(DFA),GOALS模式新版本模拟的海洋上的温度变率在中低纬度有了改善。 比较观测和模拟的年平均表面空气温度的标准差,可以发现GOALS模式四个版本都低估了海洋和陆地上的温度变率,文中还对影响观测和模拟温度变率差异的可能原因进行了探讨。 相似文献
182.
As shown in comparison and study of the HIRS-Tb12 data and conventional data, temperature,
humidity and vertical motion are structured differently in the Southern and Northern Hemispheres, which are well
depicted with the HIRS-Tb12 data. When high pressures rapidly decrease over the regions of South China Sea
and Arabian Sea with the HIRS-Tb12 less than 200 W/m2, monsoons will set off in the South China Sea, Arabian
Sea and Bay of Bengal, respectively. From a year of significant drought to one of significant floods, the trend of
evolution is significantly different in the downdraft areas of the subtropical highs between the two hemispheres. 相似文献
183.
当代气候研究计划 总被引:1,自引:0,他引:1
李崇银 《沙漠与绿洲气象(新疆气象)》2002,25(5):1-4
就气候系统问题,国际上与气候及其变化有关的重要科学计划、尤其是气候变化及可预报性研究(CLIVAR)计划,作了简要介绍,同时还就气候预测问题作了讨论。 相似文献
184.
东海陆缘(闽北段)晚第四纪沉积的硅藻学研究 总被引:10,自引:1,他引:10
对东海陆缘 (闽北段 )晚第四纪沉积 4口钻井岩心进行系统的硅藻分析研究,获得丰富的硅藻化石,共发现硅藻 117种和变种,分属于 33个属。根据剖面硅藻组合特征变化,结合最优分割法和对应序分法的计算机运算结果,可以详细划分为 12个硅藻带,自下而上为 :1.Cascinodiscusargus-Cos.wittiomus-Cyclotellastriata硅藻带,2.Cos.blandus-Cyclotellastriata硅藻带,3.Cos.excentricus-Trbliepteychuscocconiformis硅藻带,4.Gomphonema-Cos.blandus-Actnolychusralfsii硅藻带,5.Cos.-Cyclotellastriata-Actinocyclusralfsii硅藻带,6.Cos.-Actinolychusralfsii硅藻带,7.贫乏硅藻带,8.Cos.lineatus-Cos.rothii-Actinolyclusralfsii硅藻带,9.Gomphonema-Cyclotellastriata-Cocconeisplacentulavareuglypta硅藻带,10.Cos.rothii-Cyclotellastriata-Actinolychusralfsi,11.Cymbel laaffinis-Cyclotellastriata-Gomphonema硅藻带,12.Coscinodiscuswittinus-Cyclotellastriata-Epithemiahynd manii硅藻带,建立了该区晚第四纪硅藻组合序列,并探讨其相应的古环境演变。 相似文献
185.
库车坳陷侏罗纪沉积环境和层序地层分析 总被引:19,自引:0,他引:19
通过对库车坳陷野外露头和钻井资料以及地震剖面的综合分析,对库车盆地侏罗纪沉积环境、层序划分进行了研究.库车盆地在侏罗纪时期为一非对称型坳陷型盆地,主要物源在盆地的北部.划分了13个三级层序,三个层序组,反映了三个大级别的旋回.最大湖侵期为阳霞组中上部,与当时有一个明显的气候变热期相一致.沉积环境在侏罗纪早期为辫状河-辫状河三角洲环境、中期为曲流河-三角洲环境,后期为三角洲和浅湖环境,中期有短暂的海泛发生.影响侏罗纪湖平面变化的主控因素为构造运动、气候变化、物源条件、河水的流入以及海侵的影响.在中侏罗世早期、晚期的最大湖侵和海泛的短暂时期,形成了厚层的烃源岩分布.库车坳陷侏罗系虽然砂体分布广泛,厚度较大,然而由于陆相沉积环境的控制,非均质性较强、 相似文献
186.
187.
188.
The political turning point in the former GDR and the transformation processes that have been observed since then have significantly
affected economic and social structures in the new Federal States. Gender roles, however, were subjected to even more dramatic
changes. Whilst many women experienced the employment policies of the GDR era as beneficial, social researchers often designate
them as the losers of unification nowadays. This is largely because the abundance of State support measures for employed women
and mothers has been drastically reduced and women as a group have been hit hardest by the crisis on the East German labour
market. Using two cases (Mecklenburg-Westpommerania and Thuringia), this paper aims to illustrate the impact of the transformation
process on the everyday (working) lives of women. We are particularly concerned with a comparative analysis of how women experience
and deal with regional disparities in East Germany.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
189.
We present a new procedure, the pdf method (pdf=probability density function), for reconstructing Quaternary climate utilizing botanical data. The procedure includes the advantages of the indicator species method by considering the fossil and modern presence and absence of taxa rather than their frequencies, thus avoiding the need for modern analog plant communities. Overcoming the problematic use of absolute limits to describe climate response ranges is the main progress of the pdf method in comparison to the indicator species method. This advantage results from estimating probability density functions (pdfs) for monthly mean January and July temperature conditional on the present day occurrence of single taxa. Gaussian distributions sufficiently approximate pdfs of many, although not all, studied taxa. On the assumption of statistical independence, the procedure calculates a joint pdf as the product of the pdfs of the individual taxa. This algorithm weights each taxon according to the extent of its climate response range expressed by its covariance structure. We interpret the maximum of the resulting pdf as the most likely climate and its confidence interval as the uncertainty range. To avoid an artificial reduction of uncertainty arising from the use of numerous similar pdfs, a preselection method is proposed based on the Mahalanobis distance between pdfs. The pdf method was applied to the Carpinus phase of a profile from Gröbern, Germany, that spans the last interglaciation (Eemian). The reconstructed most probable January and July temperatures of about 0.0°C and 18.4°C barely differ from the modern values of −0.5°C and 18.3°C. 相似文献
190.
As a legacy of the centrally planned economy, the economies in transition of Central and Eastern Europe (CEE) have a unique
potential to reduce their greenhouse gas emissions through the improvement in their high energy intensities. Since much of
this `low-hanging fruit' in energy-efficiency improvements can be highly cost-effective, many developed countries facing difficulties
in meeting their greenhouse gas (GHG) emission targets domestically are eager to find such opportunities in the CEE region.
Therefore, studies analysing the potentials and costs of carbon dioxide reduction through technology improvement in the region
have come into the limelight. While there are a few excellent studies in the region aimed at analysing climate change abatement
potentials, they all embark on different assumptions, methodologies and boundary conditions. It is hence difficult, if not
impossible, to compare and analyse the results of these studies across different authors, countries or time horizons. Consequently,
the purpose of this paper is to place four leading studies on GHG mitigation through technology improvement from the CEE region
into an internationally comparable framework. Four studies were selected from three countries, Poland, Hungary and Estonia,
which are all the results of major national and international efforts to assess costs and potentials of GHG reduction. The
paper places their assumptions, methods and final results into a framework which enables policy-makers and project designers
to compare these across geographical and technological boundaries. Since other studies from around the globe have been analysed
in this framework in the literature, this paper provides a vehicle for the findings of these four studies to be compared to
others worldwide. In addition, the paper highlights a few areas where similar studies to be completed in the future in the
region may be enhanced by incorporating features used in GHG mitigation research in other parts of the world.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献