美韩联合研究证实了水气对全球变暖的放大效应

正2014年7月28日,《美国国家科学院院刊》(PNAS)在线发表题为《对流层上部变湿润对人为变暖的响应》(Upper Tropospheric Moistening in response to Anthropogenic Warming)的文章,证实对流层上部水气水平的增加将会加剧未来几十年的气候变化影响。该项新研究首次表明,大气中水气浓度的增加是人类活动的     

CICE5.0与BCC_CSM2.0模式的耦合及对北极海冰的模拟评估

本文将美国Los Alamos国家实验室发展的最新海冰模式CICE5.0引入国家气候中心气候系统模式BCC_CSM2.0,替代原有的海冰模式SIS,形成一个新的耦合模式。在此基础上,评估新耦合模式对1985-2009年北极海冰的模拟性能,检验引入CICE5.0后对耦合模式中北极海冰、海洋和大气模拟结果的改进。结果表明,引入CICE5.0后,模式能较好地模拟出北极海冰的空间分布、季节以及年际变化特征。相比于旧版本耦合模式,新耦合模式模拟的北极多年冰增多、一年冰减少,同时,海冰增厚、海冰流速减慢,模拟效果得到显著改进,对波弗特涡流模拟的改善尤为明显。进一步分析发现,相比于SIS,CICE5.0对北极海冰特别是海冰厚度模拟性能的提升,在耦合进入BCC_CSM2.0后,会触发冰-温的正反馈机制,改进了模式对海平面气压场、表层气温和海表温度的模拟,由此进一步提高了模式对北极海冰的模拟能力。     

FGOALS_gg1.1极地气候模拟

对中国科学院大气物理研究所大气科学和地球流体力学数值模拟国家重点实验室发展的气候系统模式FGOALS_g1.1的极地气候模拟现状进行了较为全面的评估.结果表明,FGOALS_g1.1对南北极海冰的主要分布特征、季节变化和年代际变化趋势具有一定的模拟能力.但也注意到,与观测相比,模式存在以下几方面的问题:(1)模拟的海冰总面积北极偏多,而南极偏少.北极,北大西洋海冰全年明显偏多;夏季,西伯利亚沿海海冰偏多,而波弗特海海冰偏少.南极,威德尔海和罗斯海冬季海冰偏少.南北极海冰边缘都存在异常的较大范围密集度很小的碎冰区,夏季尤为显著.(2)海冰流速在南北极海冰边缘和南极大陆沿岸附近较大.北极,模式没能模拟出波弗特涡流,并且由于模式网格中北极点的处理问题,造成其附近错误的海冰流场及厚度分布.这些海冰偏差与模式模拟的大气和海洋状况有着密切的联系.进一步分析表明,FGOALS_g1.1模拟的冰岛低压和南极绕极西风带明显偏弱,其通过大气环流和海表面风应力影响向极地的热量输送,在很大程度上导致上述的海冰偏差.此外,耦合模式中大气-海冰-海洋的相互作用可以放大子模式中的偏差.     

青藏高原能量与水循环国际合作研究的进展与展望

青藏高原能量与水循环过程对我国、东亚乃至全球的天气和气候系统都有着非常重要的作用.1996年以来,在国家自然科学基金委员会、中国科学院、中国气象局等相关部门和日本政府的大力支持下,我们针对青藏高原能量和水循环过程的重要性,成功地开展了青藏高原尺度和藏北地区中尺度的"全球能量水循环之亚洲季风青藏高原试验研究"(GAME/Tibet)项目和"全球协调加强观测计划之亚澳季风青藏高原试验研究"(CAMP/Tibet)项目近10余年的连续观测,取得了以往高原试验从未有过的大量极其珍贵的综合观测资料.而且在利用试验资料分析、卫星遥感及数值模拟等手段研究青藏高原能量与水循环方面取得大量的阶段性成果.介绍了青藏高原能量与水循环的研究进展及国际合作在项目执行过程中所起到的作用,同时介绍国际合作在吸纳境外研究资源及培养青年科技人才中所起的作用.最后提出了国际合作中存在的问题,并给出了相关的建议.     

新书架

全球气候系统卫星遥感导论——气象卫星资料的多学科应用陈渭民等编著21世纪以来,卫星探测数据应用已经进入跨学科研究的新时代,卫星资料的应用已经成为各个学科的重要内容之一。作者基于地球环境的变化及其研究的进展,在讲授气象卫星资料多学科应用课程近20年的基础上,通过多年资料收集编写了本书。本书可供大气遥感、陆地和海洋遥感专业及相关专业的本科生、研究生以及从事遥感工作的科研人员参考使用。16开定价:84.00元     

A View of Earth System Model Development

This paper gives a definition of earth system model and shows three development phases of it, including physical climate system model, earth climate system model, and earth system model, based on an inves- tigation of climate system models in the world. It provides an expatiation on the strategic significance of future development of earth system model, an introduction of some representative scientific research plans on development of earth system model home and abroad, and a review of its status and trends based on the models of the fourth assessment report （AR4） ofthe Intergovernmental Panel on Climate Change （IPCC）. Some suggestions on future development of earth system model in China are given, which are expected to be helpful to advance the development.     

BCC模式及其开展的CMIP6试验介绍

世界气候研究计划（WCRP）正在组织实施第六次国际耦合模式比较计划（CMIP6),国家气候中心作为参与单位之一,通过近几年的模式研发,推出3个最新模式版本参与该计划,包括含有气溶胶化学模块的地球系统模式BCC-ESM1.0、中等分辨率气候模式BCC-CSM2-MR和高分辨率气候模式BCC-CSM2-HR。除了CMIP6中的气候诊断、评估和描述试验（DECK）和历史气候模拟试验（Historical),这3个模式共将参与CMIP6中的10个模式比较子计划。文中主要介绍这3个模式的基本情况以及所开展的CMIP试验,并对BCC-CSM2-MR模式的Historical试验结果进行简要评估,为试验数据使用者提供参考。     

Earth System Model FGOALS-s2: Coupling a dynamic global vegetation and terrestrial carbon model with the physical climate system model

Earth System Models （ESMs） are fundamental tools for understanding climate-carbon feedback. An ESM version of the Flexible Global Ocean-Atmosphere-Land System model （FGOALS） was recently developed within the IPCC AR5 Coupled Model Intercomparison Project Phase 5 （CMIP5） modeling framework, and we describe the development of this model through the coupling of a dynamic global vegetation and terrestrial carbon model with FGOALS-s2. The performance of the coupled model is evaluated as follows. The simulated global total terrestrial gross primary production （GPP） is 124.4 PgC yr-I and net pri- mary production （NPP） is 50.9 PgC yr-1. The entire terrestrial carbon pools contain about 2009.9 PgC, comprising 628.2 PgC and 1381.6 PgC in vegetation and soil pools, respectively. Spatially, in the tropics, the seasonal cycle of NPP and net ecosystem production （NEP） exhibits a dipole mode across the equator due to migration of the monsoon rainbelt, while the seasonal cycle is not so significant in Leaf Area Index （LAI）. In the subtropics, especially in the East Asian monsoon region, the seasonal cycle is obvious due to changes in temperature and precipitation from boreal winter to summer. Vegetation productivity in the northern mid-high latitudes is too low, possibly due to low soil moisture there. On the interannual timescale, the terrestrial ecosystem shows a strong response to ENSO. The model- simulated Nifio3.4 index and total terrestrial NEP are both characterized by a broad spectral peak in the range of 2-7 years. Further analysis indicates their correlation coefficient reaches -0.7 when NEP lags the Nifio3.4 index for about 1-2 months.     

CMIP5/AMIP GCM simulations of East Asian summer monsoon

The East Asian summer monsoon （EASM） is a distinctive component of the Asian climate system and critically influences the economy and society of the region.To understand the ability of AGCMs in capturing the major features of EASM,10 models that participated in Coupled Model Intercomparison Project/Atmospheric Model Intercomparison Project （CMIP5/AMIP）,which used observational SST and sea ice to drive AGCMs during the period 1979-2008,were evaluated by comparing with observations and AMIP Ⅱ simulations.The results indicated that the multi-model ensemble （MME） of CMIP5/AMIP captures the main characteristics of precipitation and monsoon circulation,and shows the best skill in EASM simulation,better than the AMIP Ⅱ MME.As for the Meiyu/Changma/Baiyu rainbelt,the intensity of rainfall is underestimated in all the models.The biases are caused by a weak western Pacific subtropical high （WPSH） and accompanying eastward southwesterly winds in group Ⅰ models,and by a too strong and west-extended WPSH as well as westerly winds in group Ⅱ models.Considerable systematic errors exist in the simulated seasonal migration of rainfall,and the notable northward jumps and rainfall persistence remain a challenge for all the models.However,the CMIP5/AMIP MME is skillful in simulating the western North Pacific monsoon index （WNPMI）.     

我们为什么要善待海洋?

全球海洋总面积达36105.9万平方千米,地球表面约有71%的部分被蔚蓝色的海水所覆盖。海洋作为全球气候系统中的一个重要环节,通过与大气的能量物质交换和水循环等,在调节和稳定气候上发挥着决定性作用,更为人类提供了极其丰富的各类资源。