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Projection of global mean surface air temperature changes in next 40 years: Uncertainties of climate models and an alternative approach

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Science China Earth Sciences 2011年第9期54卷 1400-1406页

作者： FU congbin QIAN Cheng wu ZhaoHua Institute for Climate and Global Change Research School of Atmospheric Sciences Nanjing University Nanjing 210093 China Key Laboratory of Regional Climate-Environment for Temperate East Asia Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Department of Earth Ocean and Atmospheric Science & Center for Ocean-Atmospheric Prediction Studies Florida State University Tallahassee F132308 USA

The Fourth Assessment Report (AR4) of the Intergovernmental Panel of Climate Change (IPCC) concluded that the climate projection using climate models that took account of both human and natural factors provided credible quantitative estimates of future climate change; however, the mismatches between the IPCC AR4 model ensembles and the observations, especially the multi-decadal variability (MDV), have cast shadows on the confidence of the model-based decadal projections of future cli mate. This paper reports an evaluation of many individual runs of AR4 models in the simulation of past global mean tempera ture. We find that most of the individual model runs fail to reproduce the MDV of past climate, which may have led to the overestimation of the projection of global warming for the next 40 years or so. Based on such an evaluation, we propose an al ternative approach, in which the MDV signal is taken into account, to project the global mean temperature for the next 40 years and obtain that the global warming during 2011–2050 could be much smaller than the AR4 projection.

关键词： decadal prediction global warming multi-decadal climate variability the Ensemble Empirical Mode Decomposition CMIP3 multi-model

我国中小学科学教育的师资基础:挑战与应对——基于对16841名中小学教师的问卷调查

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中国教育学刊 2024年第6期 77-83页

作者：郭丛斌吴宇川沙桀民陈得春北京大学教育经济研究所/教育学院北京100871 北京大学教育学院北京100871

师资队伍建设是影响中小学科学教育质量的关键。基于2023年北京大学教育学院“全国义务教育学校科学教育教师调查”数据,分析发现当前我国中小学科学教育的师资基础仍然薄弱。具体表现为科学教师数量与质量有待提高,不同区域、不同特征... 详细信息

师资队伍建设是影响中小学科学教育质量的关键。基于2023年北京大学教育学院“全国义务教育学校科学教育教师调查”数据,分析发现当前我国中小学科学教育的师资基础仍然薄弱。具体表现为科学教师数量与质量有待提高,不同区域、不同特征的教师群体差异明显,教师专业发展项目的针对性与专业性不强,学校与政府对科学教育的支持力度仍显不足。建议加速科学教师培养,更新培养体系,优化师资结构;对弱势地区加大资源支持,建立不同区域间的协同发展机制;广泛开展系统性、常态化的教师培训与教研;增加科学教育经费专项投入,优化教育支出结构;完善机制,打破科学教师职业上升的天花板。

关键词：科学教育师资队伍建设科学教师科学素养

“中学生英才计划”对学生大学阶段专业承诺的影响研究

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科普研究 2024年第2期19卷 64-71,100,104,105页

作者：郭丛斌沙桀民吴宇川陈得春北京大学教育学院北京100871 北京大学教育经济研究所北京100871

“中学生英才计划”的初衷在于培养一批有志于积极投身基础学科领域的科技创新人才,这对“中学生英才计划”学生的专业承诺水平提出了较高要求。本研究基于对39所985工程高校22515名本科学生的问卷调查,分析“中学生英才计划”对学生大... 详细信息

“中学生英才计划”的初衷在于培养一批有志于积极投身基础学科领域的科技创新人才,这对“中学生英才计划”学生的专业承诺水平提出了较高要求。本研究基于对39所985工程高校22515名本科学生的问卷调查,分析“中学生英才计划”对学生大学阶段专业承诺的影响,结果显示“中学生英才计划”的学生中,男性、城镇户口、父亲学历本科及以上、大学就读于C9联盟高校、理工农医类专业的学生比例更高,高中所在区域为西部的学生比例更低。“中学生英才计划”学生的专业承诺总体水平以及理想承诺、情感承诺水平显著高于非“中学生英才计划”学生。“中学生英才计划”对学生大学阶段的专业承诺总体水平以及理想承诺、情感承诺水平存在显著正向影响。家庭社会经济背景较好、理工农医类专业的学生,其专业承诺更容易受到“中学生英才计划”的积极影响。在上述研究发现的基础上,本研究为进一步优化和完善“中学生英才计划”提出相关建议。

关键词： “中学生英才计划” 专业承诺科技创新人才

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Simulation of the direct effects of dust aerosol on climate in East Asia

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Particuology 2010年第4期8卷 301-307页

作者： Jian wu congbin Fu Zhiwei Han Jianping Tang Yanyan XU Renjian Zhang Department of Atmospheric Science Yunnan University Kunming 650091 China Key Laboratory of Regional Climate-Environment Research for Temperate East Asia Institute of Atmospheric Physics Chinese Academy of SdencesBeijing 100029 China Department of Atmaspheric Science Nanfing University Nanfing 210093 China Yunnan Meteorological Bureau Kunming 650031 China

The results from some general circulation models show distinct radiative forcing （RF） by dust aerosol, which potentially has an effect on climate change. The direct RF and regional climatic effects of dust aerosol over the East Asian region are investigated in this study using NCAR＇s Community Atmospheric Model version 3.1. The negative RF at the top of the atmosphere （TOA） and the surface （SRF） has been revealed except for some high-albedo regions, which leads to a decrease in the surface air temperature and brings an increase of atmospheric radiative heating under both clear- and all-sky conditions. The decrease in the surface air temperature can be found over a wide region that includes the Indian peninsula and northwest China. It accompanies an increase in eastern China and the Korean peninsula, and temperature changes are not limited to regions with a large dust optical depth. A belt of vapor increase is revealed from the Indian peninsula extending east to northern China, while vapor content evidently deceases in southwest China. An increase in precipitation can also be found in the belt of increased vapor accompanying the reduction of precipitation across the regions to the south of 30~N. The pattern of rainfall change helps to offset the trend of increasing wetness in the south and increasing dryness in the north of China in recent years.

关键词： Dust Radiative forcing Temperature Precipitation East Asia

Change of precipitation intensity spectra at different spatial scales under warming conditions

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Chinese Science Bulletin 2013年第8期58卷 1385-1394页

作者： wu FuTing FU congbin Institute for Climate and Global Change Research School of Atmospheric Sciences Nanjing University START/TEA Institute of Atmospheric Physics Chinese Academy of Sciences

The long-term change of the whole spectra of precipitation intensity in China is examined using observed daily data recorded at 477 surface stations for the period from 1961 to 2008. The results show a spatially coherent decrease of trace precipitation despite different reduction magnitudes among the regions. For measurable precipitation, significant regional and seasonal characteristics are observed. In autumn, the whole measurable precipitation decreased over Eastern China (east of 98°E). In summer and winter, a significant increase of heavy precipitation and decrease of light precipitation are detected south of Eastern China. In Western China, measurable precipitation is found to have increased in all four seasons. Composite analysis reveals a quasi-linear relationship between increasing surface temperature and precipitation on a global scale. The responses of precipitation at different intensities to the increased temperature are distinct, with a significant spectra-shifting from light to heavy precipitation. Compared with precipitation over the ocean, the amplification of heavy precipitation over land is relatively less, most likely constrained by the limited water supply. The response of regional precipitation to global warming shows greater uncertainties compared with those on the global scale, perhaps due to interference by more complex topography and land cover, as well as human activities, among other factors.

关键词：降水强度气候变暖空间尺度季节性特征中国东部中国西部地区表面温度全球范围

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Fully-Coupled Multi-Physical Simulation with Physics-Based Nonlinearity-Elimination Preconditioned Inexact Newton Method for Enhanced Oil Recovery

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Communications in Computational Physics 2019年第1期25卷 244-265页

作者： Huiying Tang Shihao Wang congbin Yin Yuan Di Yu-Shu wu Yonghong Wang State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengduP.R.China Petroleum Engineering Department Colorado School of MinesGoldenCO 80401USA Chuanqing Downhold Service ChengduP.R.China Department of Energy and Resources Engineering Peking UniversityBeijing 100871P.R.China CNPC Engineering Technology R&D Company Limited HoustonTexas 77042USA

In this paper,we introduce a physics-based nonlinear preconditioned Inexact Newton Method(INB)for the multiphysical simulation of fractured *** of solving the partial differential equations(PDE)exactly,Inexact Newton method finds a direction for the iteration and solves the equations inexactly with fewer ***,when the equations are not smooth enough,especially when lo-cal discontinuities exits,and when proper preconditioning operations are not adopted,the Inexact Newton method may be slow or even *** pointed out by Keyes et al.[1],multi-physical numerical simulation faces several challenges,one of which is the local-scale nonlinearity and *** this work,we have proposed and studied a nonlinear preconditioner to improve the performance of Inexact Newton *** nonlinear preconditioner is essentially a physics-based strategy to adaptively identify and eliminate the highly nonlinear *** proposed algorithm has been implemented into our fully coupled,fully implicit THM reservoir simulator(Wang et al.[2,3])to study the effects of cold water injection on fractured petroleum *** results of this work show that after the implementation of this nonlinear preconditioner,the iterative solver has become significantly more robust and efficient.

关键词： Physics-based nonlinearity-elimination Inexact Newton method thermal-hydraulic-mechanical simulation restricted additive Schwarz approach parallel reservoir simulation

On Multi-Timescale Variability of Temperature in China in Modulated Annual Cycle Reference Frame

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Advances in Atmospheric Sciences 2010年第5期27卷 1169-1182页

作者：钱诚 Zhaohua wu 符淙斌周天军 Key Laboratory of Regional Climate-Environment Research for Temperate East Asia Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 Department of Meteorology ＆ Center for Ocean-Atmospheric Prediction Studies Florida State University Tallahassee Florida USA Institute for Climate and Global Change Research Nanjing University Nanjing 210093 State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029

The traditional anomaly （TA） reference frame and its corresponding anomaly for a given data span changes with the extension of data length. In this study, the modulated annual cycle （MAC）, instead of the widely used climatological mean annual cycle, is used as an alternative reference frame for computing climate anomalies to study the multi-timescale variability of surface air temperature （SAT） in China based on homogenized daily data from 1952 to 2004. The Ensemble Empirical Mode Decomposition （EEMD） method is used to separate daily SAT into a high frequency component, a MAC component, an interannual component, and a decadal-to-trend component. The results show that the EEMD method can reflect historical events reasonably well, indicating its adaptive and temporally local characteristics. It is shown that MAC is a temporally local reference frame and will not be altered over a particular time span by an exten-sion of data length, thereby making it easier for physical interpretation. In the MAC reference frame, the low frequency component is found more suitable for studying the interannual to longer timescale variability （ILV） than a 13-month window running mean, which does not exclude the annual cycle. It is also better than other traditional versions （annual or summer or winter mean） of ILV, which contains a portion of the annual cycle. The analysis reveals that the variability of the annual cycle could be as large as the magnitude of interannual variability. The possible physical causes of different timescale variability of SAT in China are further discussed.

关键词： modulated annual cycle the Ensemble Empirical Mode Decomposition climate anomaly climate normal variability of surface air temperature in China

光栅选频单纵模35MW TEACO2激光系统

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中国激光 1986年第1期 25-28页

作者：林太基金春植李殿军杨从斌吴序华祝有信中国科学院长春光机所

本文报道了光栅调频单纵模TEA CO2激光系统,它由混合型TEA CO2振荡器和二台TEA CO2放大器组成,得到脉冲输出能量4.2J,脉宽120ns,功率35MW,可调谱线81条。

关键词：单纵模 TEACO2 激光系统光栅选频

ENSO and Southeast Asian biomass burning modulate subtropical trans-Pacific ozone transport

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National Science Review 2021年第6期8卷 120-127页

作者： Lian Xue Aijun Ding Owen Cooper Xin Huang wuke Wang Derong Zhou Zhaohua wu Audra Mc Clure-Begley Irina Petropavlovskikh Meinrat O.Andreae congbin Fu Joint International Research Laboratory of Atmospheric and Earth System Sciences School of Atmospheric SciencesNanjing University Jiangsu Provincial Collaborative Innovation Center for Climate Change Cooperative Institute for Research in Environmental Sciences University of Colorado Chemical Sciences Division NOAA Earth System Research Laboratory Department of Earth Ocean and Atmospheric SciencesFlorida State University Global Monitoring Division NOAA Earth System Research Laboratory Max Planck Institute for Chemistry Scripps Institution of Oceanography University of California

Trans-Pacific transport of enhanced ozone plumes has been mainly attributed to fossil fuel combustion in Asia in spring, but less attention has been paid to vegetation fires in Asia. Here we show that the El Ni?noSouthern Oscillation(ENSO)-modulated fires in Southeast Asia, rather than Asian fossil fuel plumes,dominate the interannual variability of springtime trans-Pacific transport of ozone across the entire North Pacific Ocean. During El Ni?no springs, the intensified fires from both the Indochinese Peninsula and Indonesia, together with large-scale circulation anomalies, result in enhanced ozone plumes that stretch over 15 000 km in both the lower-middle and upper troposphere. This enhancement is also observed in the in situ measurements of ozone concentration, with an almost 10% increase at Mauna Loa Observatory,Hawaii, a unique site to monitor the long-distance transport over the North Pacific. This study reports an unexpectedly strong influence of vegetation fires, linked with climate variability, on global tropospheric chemistry and proves once more how complex the interactions in the climate system are.

关键词： El Niño-Southern Oscillation (ENSO) climate biomass burning tropospheric ozone long-range transport Southeast Asia