一个改进的混合型海气耦合模式：ENSO模拟

通过在中国科学院大气物理研究所热带太平洋环流模式与一个统计大气模式所建立的混合型海气耦合模式中引入次表层上卷海温非局地参数化方案, 对比分析了次表层上卷海温对耦合模式模拟结果的影响, 表明在引入次表层上卷海温非局地参数化方案前耦合模式模拟的SSTA最大变率中心位于日界线附近赤道南北狭窄范围内, 而在赤道东太平洋及南美沿岸一带变率过低, 周期呈准2年振荡。改进后, 耦合模式模拟结果的分布不论在东西方向亦或南北方向与观测更为相近, 振荡周期为4年左右, 而且还能模拟出观测中ENSO振荡的季节依赖性特征。进一步分析改进的耦合模式中海气耦合特征, 表明 “延迟振子” 理论、 “西太平洋振子” 理论、 “充电-放电振子” 理论及 “平流-反射” 理论所揭示的一些规律在该模式中都能被不同程度地描述出来, 这说明在实际的ENSO循环过程中, 可能有多种机制在同时起作用。     

CAMS云分辨模式系列的研制和应用

该项目的目标是研制三维、复杂云物理的层状云模式,用于人工增雨和降水预报;研制三维、复杂云物理和地形的对流云模式,用于强对流预报和人工增雨防雹;研制中小尺度云分辨模式,用于研究α、β、γ中尺度云群的宏微观结构和演变规律;研制云辐射模式,研究辐射对云和降水的影响.该项目4次得到自然科学基金的支持,1999～2003年得到国家973项目"新一代数值预报模式的理论和方法研究"课题的支持.由中国气象科学研究院胡志晋、周秀骥、楼小凤、刘奇俊和北京大学赵春生以及秦瑜、刘玉宝、刘公波、何观芳等同志在15年内完成.     

Projected Climate Change in the Northwestern Arid Regions of China: An Ensemble of Regional Climate Model Simulations

The projected temperature and precipitationchange under different emissions scenarios using Coupled Model Intercomparison Project Phase 5 models over the northwestern arid regions of China(NWAC) were analyzed using the ensemble of three high-resolution dynamical downscaling simulations: the simulation of the Regional Climate Model version 4.0(Reg CM4) forced by the Beijing Climate Center Climate System Model version 1.1(BCC_CSM1.1); the Hadley Centre Global Environmental Model version 3 regional climate model(Had GEM3-RA) forced by the Atmosphere-Ocean coupled Had GEM version 2(Had GEM2-AO); and the Weather Research and Forecasting(WRF) model forced by the Norwegian community Earth System Model(Nor ESM1-M). Model validation indicated that the multimodel simulations reproduce the spatial and temporal distribution of temperature and precipitation well. The temperature is projected to increase over NWAC under both the 4.5 and 8.5 Representative Concentration Pathways scenarios(RCP4.5 and RCP8.5, respectively) in the middle of the 21 st century, but the warming trend is larger under the RCP8.5 scenario. Precipitation shows a significant increasing trend in spring and winter under both RCP4.5 and RCP8.5; but in summer, precipitation is projected to decrease in the Tarim Basin and Junggar Basin. The regional averaged temperature and precipitation show increasing trends in the future over NWAC; meanwhile, the large variability of the winter mean temperature and precipitation may induce more extreme cold events and intense snowfall events in these regions in the future.     

CAMS云分辨模式系列的研制和应用

该项目的目标是研制三维、复杂云物理的层状云模式，用于人工增雨和降水预报；研制三维、复杂云物理和地形的对流云模式，用于强对流预报和人工增雨防雹；研制中小尺度云分辨模式，用于研究α、β、γ中尺度云群的宏微观结构和演变规律；研制云辐射模式，研究辐射对云和降水的影响。该项目4次得到自然科学基金的支持，1999—2003年得到国家973项目“新一代数值预报模式的理论和方法研究”课题的支持。由中国气象科学研究院胡志晋、周秀骥、楼小凤、刘奇俊和北京大学赵春生以及秦瑜、刘玉宝、刘公波、何观芳等同志在15年内完成。     

一个水文模型与区域气候模式耦合的数值模拟研究(英)

在陆面过程方案中考虑精细的水文模型有助于改善对区域水文及气候的模拟。建立了一个考虑降水及入渗空间非均匀性的水文模型,并将其并入陆面过程方案BATS中。通过区域气候模式耦合模拟试验,得到如下主要结论:陆面水文的模拟对降水及入渗空间非均匀性的考虑非常敏感:考虑入渗非均匀性后,提高了径流系数,这与湿润地区水分平衡的观测结果更一致;入渗非均匀参数化方案的引入对区域水文及气候模拟的影响比降水非均匀参数化方案的引入要大:不透水面积在区域中的考虑所揭示的特征与我国北方干旱化趋势是一致的。     

一个水文模型与区域气候模式耦合的数值模拟研究

在陆面过程方案中考虑精细的水模型有助于改善对区域水及气候的模拟。建立了一个考虑降水及入诊空间非均匀性的水模型，并将其并入陆面过程方案BATS中。通过区域气候模式耦合模拟试验，得到如下主要结论：陆面水的模拟对降水及入渗空间非均匀性的考虑非常敏感；考虑入渗非均匀性后，提高了径流系数，这与湿润地区水分平衡的观测结果更一致；入渗非均匀参数化方案的引入对区域水及气候模拟的影响比降水非均匀参数化方案的引入要大；不透水面积在区域中的考虑所揭示的特征与我国北方干旱化趋势是一致的。     

基于一个不同网格相互嵌套的陆气耦合模式的气候模拟研究

将一个大气植被相互作用模式(AVIM)与大气所LASG的R15九层大气环流模式GOALS相耦合．用来模拟多年平均的全球气候状况。AVIM是一个陆地表面陆面和生理过程相互反馈的模型。作为陆气耦合的第一步,暂不考虑AVIM中的生理过程,而首光将其物理过程[相当于通常的SVAT(土壤—植被—大气—传输方案)模型]与大气所LASG的九层大气环流模式耦合起来．其中海洋模式部分不参与积分,海面温度是多年平均的气候伯。考虑到GCM的分辨率较低(7．5°×4．5°)而植被分布必须有较高的分辨率(1.5°×1.5°),采取广大气与地表面粗细网格的嵌套耦合。模式积分15年,取最后10年的平均值作分析。将模拟的气候要素场与观测值和NCEP再分析资料作了比较,气候模拟结果反映了全球环流与温湿场的主要特征,特别是降水和地面气温的模拟效果较好。这为今后气候模式与生物圈的耦合奠定广一个良好的基础。     

新疆地区未来气候变化的区域气候模式集合预估

本文基于一套在5个全球气候模式结果驱动下,RegCM4区域气候模式对东亚25km水平分辨率的集合预估,分析了中、高温室气体典型排放路径(RCP4.5和RCP8.5)下,21世纪不同时期新疆地区的未来气候变化.对模式当代气候模拟结果的检验表明,区域模式的模拟集合(ensR)总体上能够很好地再现当代新疆平均气温、降水和极端...     

An Overview of BCC Climate System Model Development and Application for Climate Change Studies

This paper reviews recent progress in the development of the Beijing Climate Center Climate System Model(BCC-CSM) and its four component models(atmosphere,land surface,ocean,and sea ice).Two recent versions are described:BCC-CSM1.1 with coarse resolution(approximately 2.8125°×2.8125°) and BCC-CSM1.1(m) with moderate resolution(approximately 1.125°×1.125°).Both versions are fully coupled climate-carbon cycle models that simulate the global terrestrial and oceanic carbon cycles and include dynamic vegetation.Both models well simulate the concentration and temporal evolution of atmospheric CO_2 during the 20th century with anthropogenic CO2 emissions prescribed.Simulations using these two versions of the BCC-CSM model have been contributed to the Coupled Model Intercomparison Project phase five(CMIP5) in support of the Intergovernmental Panel on Climate Change(IPCC) Fifth Assessment Report(AR5).These simulations are available for use by both national and international communities for investigating global climate change and for future climate projections.Simulations of the 20th century climate using BCC-CSMl.l and BCC-CSMl.l(m) are presented and validated,with particular focus on the spatial pattern and seasonal evolution of precipitation and surface air temperature on global and continental scales.Simulations of climate during the last millennium and projections of climate change during the next century are also presented and discussed.Both BCC-CSMl.l and BCC-CSMl.l(m) perform well when compared with other CMIP5 models.Preliminary analyses indicate that the higher resolution in BCC-CSM1.1(m) improves the simulation of mean climate relative to BCC-CSMl.l,particularly on regional scales.     

Preliminary Assessment of Simulations of Climate Changes over China by CMIP5 Multi-Models

Based on 18 global climate models’ simulations of the 20th century climate, a set of experiments within phase five of the Coupled Model Inter-comparison Project (CMIP5), the performances of simulating the present climate over China are assessed. Compared with observations, models can capture the dominant features of the geographic distributions of temperature and precipitation during 1961-2005. For the temporal changes of temperature, models appear to have a good performance on reproducing the warming tendency but show limited skills for precipitation. For the regional mean temperature and precipitation over the whole of China, most models underestimate the actual temperature and overestimate precipitation. Concerning the standard deviations of simulations by the 18 models, they are larger for temperature in the western part of China, while the standard deviations are larger for precipitation in the South.     

厄尔尼诺事件对商丘气候的影响

不仅厄尔尼诺事件不同的冷暖性质对商丘气候的影响不同,而且不同的起始时间、强度和持续时间对气候的影响也不同.利用1952～2000年气象资料,对厄尔尼诺的冷暖性质、发生特征进行分型,进而找到厄尔尼诺事件与本地降水和气温的统计相关关系.     

Regional Climate Change and Uncertainty Analysis based on Four Regional Climate Model Simulations over China

Four sets of climate change simulations at grid spacing of 50 km were conducted over East Asia with two regional climate models driven at the lateral boundaries by two global models for the period 1981–2050. The focus of the study was on the ensemble projection of climate change in the mid-21 st century(2031–50) over China. Validation of each simulation and the ensemble average showed good performances of the models overall, as well as advantages of the ensemble in reproducing present day(1981–2000) December–February(DJF), June–August(JJA), and annual(ANN) mean temperature and precipitation. Significant warming was projected for the mid-21 st century, with larger values of temperature increase found in the northern part of China and in the cold seasons. The ensemble average changes of precipitation in DJF, JJA, and ANN were determined, and the uncertainties of the projected changes analyzed based on the consistencies of the simulations. It was concluded that the largest uncertainties in precipitation projection are in eastern China during the summer season(monsoon precipitation).     

区域和全球模式的嵌套技术 及其长期积分试验

将区域模式嵌入澳大利亚CSIRO (Commonwealth Scientific and Industrial Research Organization）的全球模式中,并将其应用于区域模式的长期气候积分试验。模拟结果表明,当区域与全球模式嵌套时,边界吸收问题十分重要,由区域模式得到的高分辨率大尺度环流形式在边界上必须与全球模式提供的强迫一致,同时区域模式必须给出基于模式内部物理过程产生的高分辨信息。因此,在嵌套过程中,必须仔细考虑缓冲区的设置,使大尺度强迫与中尺度特征充分混合,既保持区域模式内外的一致性,又使区域内部中尺度强迫物理过程得到充分发展。将区域模式与澳大利亚CSIRO的9层21波三角形截断谱模式嵌套后,完成了连续3年的区域气候模式积分。模拟结果表明,由于区域模式较好地刻划了区域尺度的地形、下垫面和海岸线分布等的细节特征,模拟的区域气候特征比全球模式有较大的改进,尤其是对季风降水的模拟,区域模式明显改进了全球模式的模拟结果。     

Coupled Model Simulations of Climate Changes in the 20th Century and Beyond

Several scenario experiments of the IPCC 4th Assessment Report （AR4） are performed by version g1.0 of a Flexible coupled Ocean-Atmosphere-Land System Model （FGOALS） developed at the Institute of Atmospheric Physics, Chinese Academy of Sciences （IAP/CAS）, including the ＂Climate of the 20th century experiment＂, ＂CO2 1% increase per year to doubling experiment＂ and two separate IPCC greenhouse gases emission scenarios AIB and B1 experiments. To distinguish between the different impacts of natural variations and human activities on the climate change, three-member ensemble runs are performed for each scenario experiment. The coupled model simulations show： （1） from 1900 to 2000, the global mean temper- ature increases about 0.5℃ and the major increase occurs during the later half of the 20th century, which is in consistent with the observations that highlights the coupled model＇s ability to reproduce the climate changes since the industrial revolution; （2） the global mean surface air temperature increases about 1.6℃ in the CO2 doubling experiment and 1.5℃ and 2.4℃ in the A1B and B1 scenarios, respectively. The global warming is indicated by not only the changes of the surface temperature and precipitation but also the temperature increase in the deep ocean. The thermal expansion of the sea water would induce the rise of the global mean sea level. Both the control run and the 20th century climate change run are carried out again with version g1.1 of FGOALS, in which the cold biases in the high latitudes were removed. They are then compared with those from version g1.0 of FGOALS in order to distinguish the effect of the model biases on the simulation of global warming.     

厄尔尼诺事件对商丘气候的影响

不仅厄尔尼诺事件不同的冷暖性质对商丘气候的影响不同，而且不同的起始时间、强度和持续时间对气候的影响也不同。利用1952－2000年气象资料，对厄尔尼诺的冷暖性质、发生特征进行分型，进而找到尼尔尼诺事件与本地降水和气温的统计相关关系。     

气科院业务技术体制改革

中国气象科学研究院成立了以张人禾院长为组长的院业务技术体制改革领导小组，并设立了办公室。2005年是制定实施方案阶段，年底完成改革实施方案，并启动相关工作。为进一步促进科研与业务的结合，我院2005年又与上海、广东、湖北、安徽气象局签订了合作协议。     

用于IPCC第四次评估报告的气候模式比较研究简介

2005年3月1～4日,IPCC第四次评估报告气候模式比较会议（Workshop on Analyses of Climate Model Simulations for the IPCC AR4）在夏威夷举行。此次会议的主要目的是提交最新IPCC试验的初步比较结果,为IPCC第四次评估报告作准备。笔者在此对该会议中提交的科学结论做一简要介绍。     

Integrated Global System Model for Climate Policy Assessment: Feedbacks and Sensitivity Studies

Alternative policies to address global climate change are being debated in many nations and within the United Nations Framework Convention on Climate Change. To help provide objective and comprehensive analyses in support of this process, we have developed a model of the global climate system consisting of coupled sub-models of economic growth and associated emissions, natural fluxes, atmospheric chemistry, climate, and natural terrestrial ecosystems. The framework of this Integrated Global System Model is described and the results of sample runs and a sensitivity analysis are presented. This multi-component model addresses most of the major anthropogenic and natural processes involved in climate change and also is computationally efficient. As such, it can be used effectively to study parametric and structural uncertainty and to analyze the costs and impacts of many policy alternatives. Initial runs of the model have helped to define and quantify a number of feedbacks among the sub-models, and to elucidate the geographical variations in several variables that are relevant to climate science and policy. The effect of changes in climate and atmospheric carbon dioxide levels on the uptake of carbon and emissions of methane and nitrous oxide by land ecosystems is one potentially important feedback which has been identified. The sensitivity analysis has enabled preliminary assessment of the effects of uncertainty in the economic, atmospheric chemistry, and climate sub-models as they influence critical model results such as predictions of temperature, sea level, rainfall, and ecosystem productivity. We conclude that uncertainty regarding economic growth, technological change, deep oceanic circulation, aerosol radiative forcing, and cloud processes are important influences on these outputs.     

ENSO事件对中国气候的可能影响

利用 1 95 1 -1 998年的北太平洋海温和中国的温度、降水月平均资料 ,分析了ENSO事件对中国夏季主要雨带、长江中下游梅雨、华北雨季和中国秋冬季降水、温度、台风之间的可能影响 ,结果表明ENSO事件是影响中国气候的重要因素之一。