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Advances in Atmospheric Sciences 2024年第8期41卷 1463-1464页

作者： Noel KEENLYSIDE shengping he Fei LI Geophysical Institute University of Bergen and Bjerkenes Centre for Climate ResearchBergen 5007Norway Nansen Environmental and Remote Sensing Center Bergen 5007Norway Nansen-Zhu International Research Center Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China

This special issue commemorates the life work of Prof. Yongqi GAO who passed away in July 2021, his time cut short by illness. he had many great achievements, but still much more to contribute. The seven articles in this special issue are from research areas where he contributed, and they illustrate how his close colleagues are continuing his work.

关键词： Ice hemisphere Climate

Projecting Wintertime Newly Formed Arctic Sea Ice through Weighting CMIP6 Model Performance and Independence

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Advances in Atmospheric Sciences 2024年第8期41卷 1465-1482页

作者： Jiazhen ZHAO shengping he Ke FAN Huijun WANG Fei LI Key Laboratory of Meteorological Disaster Ministry of Education/Joint International Research Laboratory of Climate and Environment Change(ILCEC)/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD)Nanjing University of Information Science&TechnologyNanjing 210044China Geophysical Institute University of Bergen and Bjerknes Centre for Climate ResearchBergen 5007Norway School of Atmospheric Science Sun Yat-sen Universityand Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)Zhuhai 519082China Nansen Environmental and Remote Sensing Center and Bjerknes Centre for Climate Research Bergen 5007Norway Nansen-Zhu International Research Center Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519082China

Precipitous Arctic sea-ice decline and the corresponding increase in Arctic open-water areas in summer months give more space for sea-ice growth in the subsequent cold seasons. Compared to the decline of the entire Arctic multiyear sea ice,changes in newly formed sea ice indicate more thermodynamic and dynamic information on Arctic atmosphere–ocean–ice interaction and northern mid–high latitude atmospheric teleconnections. here, we use a large multimodel ensemble from phase 6 of the Coupled Model Intercomparison Project(CMIP6) to investigate future changes in wintertime newly formed Arctic sea ice. The commonly used model-democracy approach that gives equal weight to each model essentially assumes that all models are independent and equally plausible, which contradicts with the fact that there are large interdependencies in the ensemble and discrepancies in models' performances in reproducing observations. Therefore, instead of using the arithmetic mean of well-performing models or all available models for projections like in previous studies, we employ a newly developed model weighting scheme that weights all models in the ensemble with consideration of their performance and independence to provide more reliable projections. Model democracy leads to evident bias and large intermodel spread in CMIP6 projections of newly formed Arctic sea ice. However, we show that both the bias and the intermodel spread can be effectively reduced by the weighting scheme. Projections from the weighted models indicate that wintertime newly formed Arctic sea ice is likely to increase dramatically until the middle of this century regardless of the emissions ***, it may decrease(or remain stable) if the Arctic warming crosses a threshold(or is extensively constrained).

关键词： wintertime newly formed Arctic sea ice model democracy model weighting scheme model performance model independence

Projecting Spring Consecutive Rainfall Events in the Three Gorges Reservoir Based on Triple-Nested Dynamical Downscaling

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Advances in Atmospheric Sciences 2024年第8期41卷 1539-1558页

作者： Yanxin ZheNG Shuanglin LI Noel KEENLYSIDE shengping he Lingling SUO Department of Atmospheric Science CMA-CUG Joint Centre for Severe Weather and Climate and Hydro-geological HazardsChina University of GeosciencesWuhan 430074China Institute of Atmospheric Physics and Climate Change Research Center Chinese Academy of SciencesBeijing 100029China Three Gorges National Climatological Observatory Yichang 443099China Geophysical Institute University of Bergen and Bjerknes Centre for Climate ResearchBergen 5007Norway Nansen Environmental and Remote Sensing Center and Bjerknes Centre for Climate Research Bergen 5007Norway Nansen-Zhu International Research Centre Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China

Spring consecutive rainfall events(CREs) are key triggers of geological hazards in the Three Gorges Reservoir area(TGR), China. However, previous projections of CREs based on the direct outputs of global climate models(GCMs) are subject to considerable uncertainties, largely caused by their coarse resolution. This study applies a triple-nested WRF(Weather Research and Forecasting) model dynamical downscaling, driven by a GCM, MIROC6(Model for Interdisciplinary Research on Climate, version 6), to improve the historical simulation and reduce the uncertainties in the future projection of CREs in the TGR. Results indicate that WRF has better performances in reproducing the observed rainfall in terms of the daily probability distribution, monthly evolution and duration of rainfall events, demonstrating the ability of WRF in simulating CREs. Thus, the triple-nested WRF is applied to project the future changes of CREs under the middle-of-the-road and fossil-fueled development scenarios. It is indicated that light and moderate rainfall and the duration of continuous rainfall spells will decrease in the TGR, leading to a decrease in the frequency of CREs. Meanwhile, the duration, rainfall amount, and intensity of CREs is projected to regional increase in the central-west TGR. These results are inconsistent with the raw projection of MIROC6. Observational diagnosis implies that CREs are mainly contributed by the vertical moisture advection. Such a synoptic contribution is captured well by WRF, which is not the case in MIROC6,indicating larger uncertainties in the CREs projected by MIROC6.

关键词： triple-nested downscaling Three Gorges Reservoir area consecutive rainfall events geological hazards projection

Relative Impacts of Sea Ice Loss and Atmospheric Internal Variability on the Winter Arctic to East Asian Surface Air Temperature Based on Large-Ensemble Simulations with NorESM2

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Advances in Atmospheric Sciences 2024年第8期41卷 1511-1526页

作者： shengping he helge DRANGE Tore FUREVIK Huijun WANG Ke FAN Lise Seland GRAFF Yvan J.ORSOLINI Geophysical Institute University of Bergen and Bjerknes Centre for Climate ResearchBergen 5020Norway Nansen Environmental and Remote Sensing Center Bergen 5007Norway Key Laboratory of Meteorological Disaster Ministry of Education/Joint International Research Laboratory of Climate and Environment Change(ILCEC)/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD)Nanjing University of Information Science&TechnologyNanjing 211544China Nansen-Zhu International Research Center Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 511458China School of Atmospheric Science Sun Yat-Sen Universityand Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)Zhuhai 519082China Norwegian Meteorological Institute Oslo 0313Norway Norwegian Institute for Air Research Kjeller 2007Norway

To quantify the relative contributions of Arctic sea ice and unforced atmospheric internal variability to the “warm Arctic, cold East Asia”(WACE) teleconnection, this study analyses three sets of large-ensemble simulations carried out by the Norwegian Earth System Model with a coupled atmosphere–land surface model, forced by seasonal sea ice conditions from preindustrial, present-day, and future periods. Each ensemble member within the same set uses the same forcing but with small perturbations to the atmospheric initial state. hence, the difference between the present-day(or future) ensemble mean and the preindustrial ensemble mean provides the ice-loss-induced response, while the difference of the individual members within the present-day(or future) set is the effect of atmospheric internal variability. Results indicate that both present-day and future sea ice loss can force a negative phase of the Arctic Oscillation with a WACE pattern in winter. The magnitude of ice-induced Arctic warming is over four(ten) times larger than the ice-induced East Asian cooling in the present-day(future) experiment;the latter having a magnitude that is about 30% of the observed cooling. Sea ice loss contributes about 60%(80%) to the Arctic winter warming in the present-day(future) experiment. Atmospheric internal variability can also induce a WACE pattern with comparable magnitudes between the Arctic and East Asia. Ice-lossinduced East Asian cooling can easily be masked by atmospheric internal variability effects because random atmospheric internal variability may induce a larger magnitude warming. The observed WACE pattern occurs as a result of both Arctic sea ice loss and atmospheric internal variability, with the former dominating Arctic warming and the latter dominating East Asian cooling.

关键词： Arctic sea ice loss warm Arctic–cold East Asia atmospheric internal variability large-ensemble simulation NorESM2 PAMIP

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轴向切缝管在山岭隧道精准聚能爆破中的应用

建筑机械化 2024年第7期45卷 117-119页

作者：何盛平重庆市铁路(集团)有限公司重庆400700

针对隧道施工过程中传统爆破技术爆破参数难控制、对围岩扰动大等问题,研究了轴向切缝管技术,通过在炮孔内设置轴向排列的管壁切缝,改变爆轰波的传播方向,实现爆能量的定向释放。该技术具有聚能效果好、精度高、扰动小的优点。本文通过... 详细信息

针对隧道施工过程中传统爆破技术爆破参数难控制、对围岩扰动大等问题,研究了轴向切缝管技术,通过在炮孔内设置轴向排列的管壁切缝,改变爆轰波的传播方向,实现爆能量的定向释放。该技术具有聚能效果好、精度高、扰动小的优点。本文通过收集对比轴向切缝管在山岭隧道精准聚能爆破中的应用数据,清晰表明轴向切缝管技术可以有效提高爆破利用率,减少超挖量,提高开挖精度,加快施工进度。该技术在山岭隧道施工中具有良好应用前景。

关键词：轴向切缝管山岭隧道精准聚能爆破施工应用技术创新

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应用改进曼哈顿距离的金属超声辨识研究

中国测试 2024年第5期50卷 138-144,185页

作者：王杰贺升平贺西平周越刘昱陕西师范大学陕西省超声重点实验室陕西西安710119 四川省泸州市96038部队四川泸州646000

超声波与金属样品的显微结构相互作用而发生散射和反射等效应,造成声波能量的损失。将超声波信号与金属样品的显微组织和晶体结构联系起来,提出“超声指纹”这一概念。每个金属样品的“超声指纹”都是独一无二的,对已知的标准样品采样... 详细信息

超声波与金属样品的显微结构相互作用而发生散射和反射等效应,造成声波能量的损失。将超声波信号与金属样品的显微组织和晶体结构联系起来,提出“超声指纹”这一概念。每个金属样品的“超声指纹”都是独一无二的,对已知的标准样品采样并留存其“超声指纹”,相当于为其贴上“防伪标签”。以3类成分相近的金属样品以及每类7个成分相同的金属样品为例,利用超声相控阵的扇形扫查方式进行信号采样。将改进曼哈顿距离作为指纹特征,结合高斯分布原理和三倍标准差法计算标准样品的辨识阈值,相较于以前的阈值计算方法更加科学合理。测试结果表明,提出的方法能够对成分相近金属样品甚至成分相同的金属样品全部实现准确辨识。

关键词：超声波金属样品防伪辨识改进曼哈顿距离阈值

维普期刊数据库博看期刊

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高钛钢液面温度及“结鱼”形成的控制

钢铁 2024年第1期59卷 58-66,74页

作者：王时松王云波唐庆张旭彬何生平青岛特殊钢铁有限公司研究院山东青岛266400 青岛特殊钢铁有限公司炼钢厂山东青岛266400 重庆大学材料科学与工程学院重庆400044

在高钛钢的生产过程中,由于钢中的钛与氮容易生成TiN夹杂物,并部分在结晶器内钢渣界面处聚集,这容易在钢液面低温区诱发“结鱼”的形成而导致高钛钢难以顺利连铸。针对高钛钢连铸“结鱼”产生的问题,采用数值模拟的方法,讨论了不同电磁... 详细信息

在高钛钢的生产过程中,由于钢中的钛与氮容易生成TiN夹杂物,并部分在结晶器内钢渣界面处聚集,这容易在钢液面低温区诱发“结鱼”的形成而导致高钛钢难以顺利连铸。针对高钛钢连铸“结鱼”产生的问题,采用数值模拟的方法,讨论了不同电磁搅拌强度、拉速和过热度等连铸参数对钢液面温度的影响,并对保护渣的碱度进行了优化,以通过提高钢液面温度来降低结晶器内“结鱼”的形成。通过建立的数学模型模拟发现,在浇铸拉速为0.85m/s和1.05m/s时,在结晶器内施加电磁搅拌均能引起钢液面温度的升高,且当搅拌电流为200A时钢液面的温度最高;在电磁搅拌强度一定时,提高拉速和浇铸过热度均能提高结晶内钢液面的温度,并能减小结晶器角部低温区域的大小;现场试验发现,除拉速外,在其他连铸参数一定时,浇铸过热度由25K提高到60K后,连铸结晶器内未发现“结鱼”物的形成,且连铸坯表面的夹渣缺陷明显降低;将连铸保护渣碱度由0.60提高到0.88后,保护渣的结晶性能增强,控制传热能力改善,在高过热度浇铸过程中结晶器内液渣层的厚度由6mm增加到为8mm,这说明钢液面的温度升高,但该保护渣在低过热度浇铸(40K)时也未发现“结鱼”的发生。因此,高钛钢连铸过程中的“结鱼”形成受钢液面的温度的影响,通过提高浇铸过热度和改善连铸保护渣控制传热的能力均能控制结晶器内“结鱼”的形成,优化渣可用于高钛钢的低过热度浇铸生产,为改善高钛钢的可浇性提供理论指导。

关键词：高钛钢连铸结晶器结鱼物钢液面温度数值模拟

Relationship between Solar Wind-Magnetosphere Energy and Eurasian Winter Cold Events

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Advances in Atmospheric Sciences 2020年第6期37卷 652-661页

作者： Xinping XU shengping he Huijun WANG Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters/Key Laboratory of Meteorological Disaster Ministry of EducationNanjing University of Information Science and TechnologyNanjing 210044China Geophysical Institute University of Bergen and Bjerknes Centre for Climate ResearchBergen 5007Norway Nansen-Zhu International Research Center Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Climate Change Research Center Chinese Academy of SciencesBeijing 100029China

The profound impact of solar irradiance variations on the decadal variability of Earth’s climate has been investigated by previous ***,it remains a challenge to quantify the energetic particle precipitation(EPP)influence on the surface climate,which is an emerging research *** solar wind is a source of magnetospheric EPP,and the total energy input from the solar wind into Earth’s magnetosphere(Ein)shows remarkable interdecadal and interannual variability.B ased on the new Ein index,this study reveals a significant interannual relationship between the annual mean Einand Eurasian cold extremes in the subsequent *** frequent cold events are observed over Eurasia(primarily north of 50°N)following the higher-than-normal Ein activity in the previous year,accompanied by more frequent cold events over northern Africa,and vice *** response pattern shows great resemblance to the first empirical orthogonal function of the variability of cold extremes over Eurasia,with a spatial correlation coefficient of *** pronounced intensification of the positive North Atlantic Oscillation events and poleward shift of the North Atlantic storm track associated with the anomalously higher Ein favor the anomalous extreme atmospheric circulation events,and thus less frequent extreme cold temperatures over northern Eurasia on the interannual time *** is further hypothesized that the wave-mean flow interaction in the stratosphere and troposphere is favorable for the connection of Ein signals to tropospheric circulation and climate in the following winter.

关键词： Eurasian interannual winter

Weakening relationship between East Asian winter monsoon and ENSO after mid-1970s

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Chinese Science Bulletin 2012年第27期57卷 3535-3540页

作者： WANG HuiJun he shengping Nansen-Zhu International Research Center Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Climate Change Research Center Chinese Academy of SciencesBeijing 100029China Graduate University of Chinese Academy of Sciences Beijing 100049China

The East Asian winter monsoon(EAWM) is characterized by the frequent cold surges and associated closely with the Siberia High,East Asian Trough,and high-level westerly jet *** ENSO cycle can modulate the EAWM since it has co-variability with the sea surface temperature over the Indo-Western-Pacific which can tune the land-sea thermal contrast for the *** paper,by analyzing the EAWM,ENSO,and associated atmosphere-ocean variability,documents the weakening of the EAWMENSO relationship after the *** significant out-of-phase inter-relationship is found to be diminished after the *** study in this work suggests that the weakened co-variability of the tropical Indo-Western-Pacific climate associated with ENSO after the 1970s is partly responsible for the weakened ***,the reduced EAWM interannual variability and northward retreat of the EAWM-associated climate variability are favorable to the weakened ENSO-EAWM connection.

关键词： ENSO循环东亚冬季风年代热带印度洋中期西太平洋气候变化海表面温度

高钛钢连铸保护渣对Al_(2)O_(3)夹杂物吸收性的研究

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炼钢 2024年第3期40卷 66-71,81页

作者：王学友王军张旭彬何生平重庆大学材料科学与工程学院重庆400044 湖南华菱湘潭钢铁集团有限公司技术中心湖南湘潭411100

针对高钛钢连铸保护渣钢渣反应及吸收夹杂物的变性问题,采用热力学计算、保护渣性能测试和旋转柱法等方法,对高钛钢钢液内夹杂物的生成种类和不同温度下的生成量进行了计算,根据夹杂物的生成情况对比了传统CaO-SiO_(2)系和新开发的低反... 详细信息

针对高钛钢连铸保护渣钢渣反应及吸收夹杂物的变性问题,采用热力学计算、保护渣性能测试和旋转柱法等方法,对高钛钢钢液内夹杂物的生成种类和不同温度下的生成量进行了计算,根据夹杂物的生成情况对比了传统CaO-SiO_(2)系和新开发的低反应性BaO-Al_(2)O_(3)-SiO_(2)-TiO_(2)系保护渣吸收夹杂物的性能变化,并对比了两种保护渣对夹杂物的吸收速率。热力学计算表明,研究的高钛钢中铝质量分数为0.03%、钛质量分数为0.40%,钢液中生成的夹杂物为Al_(2)O_(3),而实际生产中由于钢液局部成分差异可能有钛氧化物的生成;从保护渣吸收夹杂物前后的性能对比可知,两种保护渣的黏度和熔点均随其吸收Al_(2)O_(3)含量的增加而增加,但新开发的低反应性保护渣相对于CaO-SiO_(2)系渣的性能变化更小,其性能更稳定;由旋转柱试验可知,CaO-SiO_(2)系和BaO-Al_(2)O_(3)-SiO_(2)-TiO_(2)系保护渣对氧化铝棒的吸收速率分别在(8~12)×10^(-3) g/(cm^(2)·min)和(10~13)×10^(-3) g/(cm^(2)·min),后者对夹杂物的吸收能力更强。因此,新开发的BaO-Al_(2)O_(3)-SiO_(2)-TiO_(2)系低反应性保护渣有潜力用于更高钛含量的钢种浇铸。

关键词：高钛钢保护渣夹杂物氧化铝