20世纪60年代中期亚非夏季风减弱的全球气候背景异常分析

利用美国NASA格点月降水总量资料、美国CO2信息分析中心地表面温度异常月平均网格点资料、美国NCEP/NCAR再分析全球网格点资料和兰州高原大气物理研究所的台站地温观测资料分析了1960年代中期亚非夏季风环流圈年代际时间尺度的减弱及其与之有关的全球气候场异常现象。结果发现, 1960年代中期全球对流层大气温度和海洋温度场发生异常变化, 对流层大气有明显降温, 海洋主要以印度洋升温、 北太平洋和北大西洋降温为主要特征, 同时, 我国大陆土壤温度和青藏高原温度在1960年代中期有明显的下降, 导致亚洲大陆与印度洋之间的热力对比明显减弱, 东风急流减弱, 最终导致亚非夏季风明显减弱。     

An Updated Coupled Model for Land-Atmosphere Interaction. Part II： Simulations of Biological Processes

In Part I, the authors succeeded in coupling the spectral atmospheric model （SAMIL_R42L9） developed at the State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics, Institute of Atmospheric Physics, Chinese Academy of Sciences （LASG/IAP/CAS） with the land surface model, Atmosphere-Vegetation-Interaction-Model （AVIM） and analyzed the climate basic state and land surface physical fluxes simulated by R42_AVIM. In this Part Ⅱ, we further evaluate the simulated results of the biological processes, including leaf area index （LAI）, biomass and net primary productivity （NPP） etc. Results indicate that R42_AVIM can simulate the global distribution of LAI and has good consistency with the monthly mean LAI provided by Max Planck Institute for Meteorology. The simulated biomass corresponds reasonably to the vegetation classifications. In addition, the simulated annual mean NPP has a consistent distribution with the data provided by IGBP and MODIS, and compares well with the work in literature. This land-atmosphere coupled model will offer a new experiment tool for the research on the two-way interaction between climate and biosphere, and the global terrestrial ecosystem carbon cycle.     

有序人类活动与生存环境

提出了有序人类活动的概念，认为有序人类活动即：通过合理安排和组织，使自然环境能在长时期，大范围不发生明显退化，甚至能持续好转，同时又能满足当时社会经济发展对自然资源和环境的需求的人类活动。在分析有序人类活动与可持续发展等相关概念的关系的基础上，概括了有序人类活动概念提出的背景，列举了有序人类活动的主体及其功能，分析了有序人类活动的特征，并且介绍了有序人类活动的研究内容和方法。     

The Interactive Climate and Vegetation Along the Pole-Equator Belts Simulated by a Global Coupled Model

The interaction between climate and vegetation along four Pole-Equator-Pole （PEP） belts were explored using a global two-way coupled model, AVIM-GOALS, which links the ecophysiological processes at the land surface with the general circulation model （GCM）. The PEP belts are important in linking the climate change with the variation of sea and land, including terrestrial ecosystems. Previous PEP belts studies have mainly focused on the paleoclimate variation and its reconstruction. This study analyzes and discusses the interaction between modern climate and vegetation represented by leaf area index （LAI） and net primary production （NPP）. The results show that the simulated LAI variation, corresponding to the observed LAI variation, agrees with the peak-valley variation of precipitation in these belts. The annual mean NPP simulated by the coupled model is also consistent with PIK NPP data in its overall variation trend along the four belts, which is a good example to promote global ecological studies by coupling the climate and vegetation models. A large discrepancy between the simulated and estimated LAI emerges to the south of 15°N along PEP 3 and to the south of 18°S in PEP 1S, and the discrepancy for the simulated NPP and PIK data in the two regions is relatively smaller in contrast to the LAI difference. Precipitation is a key factor affecting vegetation variation, and the overall trend of LAI and NPP corresponds more obviously to precipitation variation than temperature change along most parts of these PEP belts.     

1981~2000年中国陆地净生态系统生产力空间格局及其变化

中国地域辽阔, 跨越多个气候带, 生态环境条件复杂多样, 因此研究其生态系统碳循环的空间格局及其对气候变化的响应有十分重要的意义. 应用高分辨率的气候数据库和生态系统过程模型估计了1981~2000年期间中国陆地净生态系统生产力 (Net Ecosystem Productivity, NEP)的时空变化, 分析了中国陆地碳汇的地域分布及其对气候变化的响应. 结果表明, NEP的20年平均值呈现北方高南方低、中部和西南地区高、东南地区低的格局; NEP正值(碳吸收)主要在西南地区西部、藏东南、三江平原、大兴安岭以及华北中西部, NEP负值(碳释放)主要在华中、西南南部、新疆北部、内蒙西北部、华北平原一些地区. 从20世纪80年代到90年代, 东北平原中部和黄土高原的NEP有明显的下降趋势, 而在华中大部分地区有增加趋势. 研究时段内中国森林生态系统的碳吸收不明显, 其在20世纪80年代是一个碳源, 但在90年代转为一个碳汇; 草地和灌丛由于面积广阔, 其碳吸收量占整个中国陆地生态系统碳吸收总量的近四分之三.     

小冰期气候研究回顾和机理探寻

回顾了古气候学中利用代用气象资料对小冰期气候重建的研究结果，归纳出小冰期时期全球气候特征及东亚季风区域气候特征，分析了小冰期气候形成的可能原因，介绍了国外有关小冰期气候成因的数值模拟现状，并对未来模拟工作发展方向提出了建议。     

60年代亚非夏季风十年尺度的突变

在综合分析了近几十年气候资料的基础上，揭示了本世纪60年代的一次亚非夏季风十年尺度的突变。这次突变在地面温度场上表现为突变前亚非大陆是正距平，印度洋和西太平洋为负距平，海陆温差较强；突变后相反，海陆温差减弱。地面气压由突变前亚非大陆强热低压中心转变为突变后的弱低压中心。同时突变前北非和东亚夏季风增强，而突变后明显减弱。这次十年尺度的气候突变突出表现了东亚季风、印度季风和北非季风明显的变化同步性，而最显著的特征是在行星尺度的降水场上从北非撒哈拉－萨赫勒、中东、印度北部到华北干旱半干旱带上由多雨变为少雨的雨量减少带。     

INFLUENCE OF SOIL MOISTURE AND VEGETATION ON CLIMATE CHANGES INDUCED BY THERMAL FORCING

A land-process scheme has been incorporated in a vertical one-dimensional time-dependent atmospheric modeland numerical experiments have been performed with the coupled model to examine influences of soil wetness and vege-tation on climate changes associated to thermal forcing.It is showed that response of land-surface temperature to thethermal forcing becomes small with increase of soil water content and vegetation cover.Furthermore,the response ismore obvious in arid climate region than in humid one.The result also shows that there exist two patterns of corre-sponding relation between variations in air temperature and humidity on the land surface in response to hydrologic andthermal focing.     

大气-生物圈相互作用的层次性——兼对模式研究的述评

从大气和生物圈构成的层次性出发,提出了大气—生物圈相互作用的三个层次,在此框架基础上,分析了不同研究(模式)的特点,并强调指出建立大气—植物圈(植被)层次上的相互作用模式是使相互作用研究真正建立在动态的、完整的基础之上的关键。