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Observed,Reconstructed,and Simulated Decadal Variability of Summer Precipitation over Eastern China

Journal of Meteorological Research 2017年第1期31卷 49-60页

作者： Jingyun ZHENG Maowei WU Quansheng GE Zhixin HAO xuezhen zhang Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences University of Chinese Academy of Sciences College of Resources and Environment

Based on observations made during recent decades, reconstructed precipitation for the period A.D. 1736-2000, dry-wet index data for A.D. 500-2000, and a 1000-yr control simulation using the Community Earth System Model with fixed pre-industrial external forcing, the decadal variability of summer precipitation over eastem China is stud- ied. Power spectrum analysis shows that the dominant cycles for the decadal variation of summer precipitation are： 22-24 and quasi-70 yr over the North China Plain; 32-36, 44-48, and quasi-70 yr in the Jiang-Huai area; and 32-36 and 4448 yr in the Jiang-Nan area. Bandpass decomposition from observation, reconstruction, and simulation re- veals that the variability of summer precipitation over the North China Plain, Jiang-Huai area, and Jiang-Nan area, at scales of 20-35, 35-50, and 50-80 yr, is not consistent across the entire millennium. We also find that the warm （cold） phase of the Pacific Decadal Oscillation generally corresponds to dry （wet） conditions over the North China Plain, but wet （dry） conditions in the Jiang-Nan area, from A.D. 1800, when the PDO became strengthened. However, such a correspondence does not exist throughout the entire last millennium. Data-model comparison sug- gests that these decadal oscillations and their temporal evolution over eastem China, including the decadal shifts in the spatial pattem of the precipitation anomaly observed in the late 1970s, early 1990s, and early 2000s, might result from internal variability of the climate system.

关键词： decadal variability dominant cycle summer precipitation eastern China data-model comparison

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Comparisons of cropland area from multiple datasets over the past 300 years in the traditional cultivated region of China

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Journal of Geographical Sciences 2013年第6期23卷 978-990页

作者： HE Fanneng LI Shicheng zhang xuezhen GE Quansheng DAI Junhu Institute of Geographic Sciences and Natural Resources Research CAS Beijing 100101 China University of Chinese Academy of Sciences Beijing 100049 China

Land use/cover change is an important parameter in the climate and ecological simulations. Although they had been widely used in the community, SAGE dataset and HYDE dataset, the two representative global historical land use datasets, were little assessed about their accuracies in regional scale. Here, we carried out some assessments for the traditional cultivated region of China （TCRC） over last 300 years, by comparing SAGE2010 and HYDE （v3.1） with Chinese Historical Cropland Dataset （CHCD）. The comparisons were performed at three spatial scales： entire study area, provincial area and 60 km by 60 km grid cell. The results show that （1） the cropland area from SAGE2010 was much more than that from CHCD moreover, the growth at a rate of 0.51% from 1700 to 1950 and -0.34% after 1950 were also inconsistent with that from CHCD. （2） HYDE dataset （v3.1） was closer to CHCD dataset than SAGE dataset on entire study area. However, the large biases could be detected at provincial scale and 60 km by 60 km grid cell scale. The percent of grid cells having biases greater than 70% （〈-70% or 〉70%） and 90% （〈-90% or 〉90%） accounted for 56%-63% and 40%-45% of the total grid cells respectively while those having biases range from -10% to 10% and from -30% to 30% account for only 5%-6% and 17% of the total grid cells respectively. （3） Using local historical archives to reconstruct historical dataset with high accuracy would be a valu- able way to improve the accuracy of climate and ecological simulation.

关键词： cropland datasets comparisons past 300 years traditional cultivated region China

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国内外聚乙烯的生产与消费

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现代化工 2000年第10期20卷 53-54,56页

作者：张雪珍北京化工研究院信息中心 100013

1999年世界聚乙烯的生产能力约为 5 660万t/a ,需求量约为 4 81 0万t。 90年代后期 ,企业合并成为PE工业的热点。我国PE工业发展很快 ,目前共有生产装置 34套 ,总生产能力达 2 83 2 7万t/a,1 999年表观消费量达 51 6 8万t,预计需求将以 ... 详细信息

1999年世界聚乙烯的生产能力约为 5 660万t/a ,需求量约为 4 81 0万t。 90年代后期 ,企业合并成为PE工业的热点。我国PE工业发展很快 ,目前共有生产装置 34套 ,总生产能力达 2 83 2 7万t/a,1 999年表观消费量达 51 6 8万t,预计需求将以 1 0 %的年均增长率增长。

关键词：稀乙烯生产需求预测世界

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Changes of spring phenodates for the past 150 years over the Yangtze River Delta

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Journal of Geographical Sciences 2013年第1期23卷 31-44页

作者： ZHENG Jingyun ZHONG Shuying GE Quansheng HAO Zhixin zhang xuezhen MA Xiang Institute of Geographic Sciences and Natural Resources Research CAS Beijing 100101 China

Based on phenological records extracted from Chinese historical dairies, spring phenological series in the Yangtze River Delta （YRD） of China since 1834 is reconstructed. Together with temperature and phenological observation data, the indicating significance of spring phenological series to temperature changes is also analyzed. The results are shown as follows. （1） From 1834 to 1893, spring phenodate in the YRD was fluctuated and gradually delayed, but, advanced greatly at the end of the 19th century. From 1900 to 1990, although the decadal variations were found, no clear multi-decadal trend was detected. From 1990 to 2010, spring phenodate showed significantly advance again. Compared with the mean value for 1977-1996, the latest phenodate occurred in 1893 with 27 days delayed while the earliest phenodate occurred in 2007 with 17 days advanced. （2） The correlation coefficients between spring phenodates and temperatures from December to March and from January to March exceeded -0.75 and -0.80, respectively, indicating that our phenodate series well presents the long-term changes of winter and early spring （especially from January to March） tem- peratures. These results provide important basic data for the long-term integrated tempera- ture reconstruction over China in the future work.

关键词： historical diaries spring phenodates changes the Yangtze River Delta past 150 years

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黄土高原植被恢复对土壤物理参数的影响——基于已发表数据的荟萃分析

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地理科学进展 2021年第6期40卷 1012-1025页

作者：张泽凡张学珍中国科学院地理科学与资源研究所中国科学院陆地表层格局与模拟重点实验室北京100101 中国科学院大学北京100049

陆面过程在气候变化中具有重要作用,其中土壤水文过程是陆面过程的重要内容,然而目前陆面模式中土壤水力学参数仅依赖于土壤质地,并未考虑植被类型对其影响,这与自然过程不符,从而导致对大规模植被恢复的水文、气候效应认识不充分。为... 详细信息

陆面过程在气候变化中具有重要作用,其中土壤水文过程是陆面过程的重要内容,然而目前陆面模式中土壤水力学参数仅依赖于土壤质地,并未考虑植被类型对其影响,这与自然过程不符,从而导致对大规模植被恢复的水文、气候效应认识不充分。为揭示植被恢复对土壤物理参数的影响,改进陆面模式中土壤参数的精度,论文以黄土高原为研究对象,收集整理了已发表的植被恢复下土壤物理参数的测试分析数据,从中提取了采样点经纬度、土壤质地、植被类型、恢复年限、坡度、孔隙度等信息,进行了荟萃分析。结果显示,植被恢复可促进土壤有机质的积累,明显改善土壤结构、增加土壤肥力,从而提高土壤黏粒含量,降低砂粒含量,显著提高土壤孔隙度、饱和导水率和持水能力。随着植被覆盖度的增加,这种作用也增强,恢复至林地阶段达到最高,并且阔叶林的作用要强于针叶林。随林龄增长,土壤孔隙结构和入渗性能都明显改善,土壤的持水性得到增强。研究明确了黄土高原地区植被恢复对土壤参数的影响,为更好地研究大规模植被恢复对地表水分通量的影响及其气候效应奠定了基础。

关键词：植被恢复土壤物理参数荟萃分析黄土高原

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A comparative study of seismic tomography models of the Chinese continental lithosphere

A comparative study of seismic tomography models of the Chin...

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2022年中国地球科学联合学术年会

作者： zhang xuezhen Song Xiaodong Li Jiangtao

The Chinese mainland is subject to complicated plate interactions that give rise to its complex structure and tectonics. While several seismic velocity models have been developed for the Chinese mainland, apparent dis... 详细信息

关键词： A comparative study of seismic tomography models of the Chinese continental lithosphere

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Status of Laser Ion Source Development in 2018

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IMP & HIRFL Annual Report 2018年第1期 241-242页

作者： Zhao Huanyu zhang Junjie Shen Dingding Wang Guicai zhang xuezhen Sun Liangting Zhao Hongwei 不详

In 2018,the technology of the proton beam production with a laser ion source was *** produce proton beams with the laser ion source,a solidified hydrogen target system had been developed by the end of *** experiment on the production of proton beams with the laser ion source was carried out at the beginning of *** 8 ns laser pulse with the 0.5 J energy was focused with a lens of f=500 mm onto the hydrogen ice deposited on a copper sheet attached at the second stage of a 4.2 K *** laser power density on the ice was estimated to 2.5109 Wcm−*** shown in Fig.1(a)and(b),the condition of the hydrogen ice formation can be observed through the laser window before each laser *** waveform of the proton beam,shown in Fig.1(c),was measured with a Faraday Cup located 2.5 m away from the *** shown in Fig.1(c),the current intensity of the proton beam was much lower than other ion *** the repeatability of the proton beam pulses was also poor,the main reason of which is that the conditions of the deposited hydrogen ice were quite different from shot to shot.

关键词： attached beam Faraday

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6-41 Research Status of Laser Ion Sources and DPIS at IMP

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IMP & HIRFL Annual Report 2014年第1期 298-299页

作者： Zhao Huanyu zhang Junjie Jin Qianyu Liu Wei Lu Liang Sun Liangting zhang xuezhen 不详

In 2014, the study on laser ion sources at IMP was mainly focused on the carbon ion production with a doublepulselaser irradiation scheme, simulations of Direct Plasma Injection Scheme (DPIS), and PoP experiments onlaser ion beam acceleration in a Hybrid Single Chamber (HSC) Linac with *** optical method was developed to realize thedouble-pulse laser irradiation scheme, with which onecan irradiate a target with two successive laser pulsesusing only one laser. As shown in Fig. 1, the laser beamoutput by a 3 J/ 8 ns Nd:YAG laser is split into twobeams by a beam splitter, then the two laser beamspassing through different optical paths are combined byanother splitter and transported by the same optical system.

关键词： Research Status Laser

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Bremsstrahlung Measurement at 24 GHz on SECRAL

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近代物理研究所和兰州重离子加速器实验室年报：英文版 2009年第1期 272-273页

作者： Zhao Huanyu zhang Wenhui Ma Hongyi Sun Liangting Lu Wang Cao Yun zhang xuezhen Zhao Hongwei

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基于模式优选的21世纪中国气候变化情景集合预估

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地理学报 2017年第9期72卷 1555-1568页

作者：张学珍李侠祥徐新创张丽娟中国科学院地理科学与资源研究所中国科学院陆地表层格局与模拟重点实验室北京100101 哈尔滨师范大学黑龙江省普通高等学校地理环境遥感监测重点实验室哈尔滨150025 湖北科技学院资源环境科学与工程学院咸宁437100

未来气候变化情景预估是制定气候变化应对和适应策略的科学基础。本文利用参与耦合模式比较计划第五阶段(CMIP5)的30个气候模式的模拟数据,通过评估各模式对历史气候变化的模拟能力,筛选出模拟区域气候变化的最优模式组合,进而建立偏最... 详细信息

未来气候变化情景预估是制定气候变化应对和适应策略的科学基础。本文利用参与耦合模式比较计划第五阶段(CMIP5)的30个气候模式的模拟数据,通过评估各模式对历史气候变化的模拟能力,筛选出模拟区域气候变化的最优模式组合,进而建立偏最小二乘回归(PLS)集合预估模型,据此利用最优模式模拟结果预估区域温度和降水变化情景。通过与历史数据的对比,研究发现本文基于最优模式建立的PLS集合预估模型不仅优于传统的多模式集合平均,而且也优于利用全部模式建立的PLS集合预估模型,体现了模式优选过程的重要性。本文基于优选模式的PLS集合预估模型预估结果表明:(1)21世纪各区域温度将持续上升,且冬半年升温速率总体大于夏半年,北方地区升温速率总体高于南方地区;RCP 4.5排放情景下温度上升先快后慢,转折点出现在21世纪中期,RCP 8.5排放情景下,呈持续增加趋势,至21世纪末的升温幅度约为RCP 4.5情景的2倍。(2)21世纪各区降水变化均呈显著增加趋势,并表现出高排放情景大于低排放情景,少雨区大于多雨区的特征,但是降水增加过程伴有明显的年代际波动。对比发现,传统的等权重集合平均全部模式(EMC)方法预估的中国夏季变暖速率高于冬季,且降水基本呈线性增加,有悖于全球变暖的基本特征及中国降水具有鲜明的年代际变化特征的基本认识。因而,本文预估的温度和降水变化特征均更符合中国气候变化的基本规律。

关键词： CMIP5 中国气候变化模式优选多模式集合情景预估

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