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基于循环神经网络的欧亚中高纬夏季极端高温年代际预测模型研究

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大气科学学报 2024年第2期47卷 273-283页

作者：索朗多旦黄艳艳陈雨豪王会军南京信息工程大学气象灾害教育部重点实验室/气候与环境变化国际合作联合实验室/气象灾害预报预警与评估协同创新中心江苏南京210044 工布江达县气象局西藏林芝860000 南方海洋科学与工程广东省试验室(珠海) 广东珠海519080

近几十年来频繁发生的极端高温事件严重威胁着自然生态系统、社会经济发展和人类生命安全。针对生态环境脆弱的欧亚中高纬地区,首先评估了当前主流动力模式(CMIP6 DCPP)对于该地区夏季极端高温的年代际预测水平,并构建了基于循环神经网... 详细信息

近几十年来频繁发生的极端高温事件严重威胁着自然生态系统、社会经济发展和人类生命安全。针对生态环境脆弱的欧亚中高纬地区,首先评估了当前主流动力模式(CMIP6 DCPP)对于该地区夏季极端高温的年代际预测水平,并构建了基于循环神经网络(Recurrent Neural Networks,RNN)的年代际预测模型。多模式集合平均(Multi-Model Ensemble,MME)的评估结果显示,得益于大样本和初始化的贡献,当前动力模式对于60°N以南区域(South Eurasia,SEA)展现了预测技巧,准确预测出了其线性增长趋势和1968—2008年间主要的年代际变率,然而模式对于60°N以北区域(North Eurasia,NEA)极端高温的年代际变率几乎没有任何预测技巧,仅预测出比观测低的线性增长趋势。基于86个初始场的动力模式大样本预测结果,RNN将2008—2020年间NEA和SEA极端高温的年代际变率预测技巧显著提高,距平相关系数技巧从MME中的-0.61和-0.03,提升至0.86和0.83,均方差技巧评分从MME中的-1.10和-0.94,提升至0.37和0.52。RNN的实时预测结果表明,在2021—2026年,SEA区域的极端高温将持续增加,2026年很可能发生突破历史极值的极端高温事件,NEA区域在2022年异常偏低,而后将呈现波动上升。

关键词：极端高温 DCPP 年代际预测循环神经网络

Ⅱ型鼠李半乳糖醛酸聚糖的制备方法和结构表征的研究进展

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中国药科大学学报 2024年第4期55卷 432-442页

作者：刘育朋施松善步盈萱龚欢王辉俊王顺春上海中医药大学中药研究所上海201203 中药标准化教育部重点实验室上海201203

Ⅱ型鼠李半乳糖醛酸聚糖(RG-Ⅱ)是果胶结构域中的一种,其结构在不同物种之间具有高度的保守性。RG-Ⅱ的主链由约9个半乳糖醛酸经α-1,4糖苷键连接而成,并被6个(A–F)明确定义的侧链取代。其中二糖侧链C、D和单糖侧链E、F的结构在不同来... 详细信息

Ⅱ型鼠李半乳糖醛酸聚糖(RG-Ⅱ)是果胶结构域中的一种,其结构在不同物种之间具有高度的保守性。RG-Ⅱ的主链由约9个半乳糖醛酸经α-1,4糖苷键连接而成,并被6个(A–F)明确定义的侧链取代。其中二糖侧链C、D和单糖侧链E、F的结构在不同来源的RG-Ⅱ中基本保持相同。寡糖侧链A和B则存在轻微的变异性。通过相对分子质量、单糖组成和质谱分析等手段可实现RG-Ⅱ的结构表征。中药中含有RG-Ⅱ结构域的多糖具有很高的药用价值,使用内切多聚半乳糖醛酸酶(Endo-PG)和草酸青霉可将RG-Ⅱ从中药中分离并对其在多糖中的含量进行测定。从葡萄酒中可快速制备大量RG-Ⅱ标准品用于新定量方法的开发,实现对中药活性多糖的质量控制,推动中药多糖的研究进程。

关键词：果胶 Ⅱ型鼠李半乳糖醛酸聚糖 RG-Ⅱ 内切多聚半乳糖醛酸酶草酸青霉葡萄酒

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Projection of Landslides in China during the 21st Century under the RCP8.5 Scenario

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Journal of Meteorological Research 2019年第1期33卷 138-148页

作者： Shuangshuang HE Jun wang huijun wang Nansen–Zhu International Research Centre Institute of Atmospheric Physics Chinese Academy of Sciences University of Chinese Academy of Sciences Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science &Technology Key Laboratory of Meteorological Disaster Nanjing University of Information Science & Technology

More and more rainstorms and other extreme weather events occur in the context of global warming, which may increase the risks of landslides. In this paper, changes of landslides in the 21 st century of China under the high emission scenario RCP8.5(Representative Concentration Pathway) are projected by using a statistical landslide forecasting model and the regional climate model RegCM4.0. The statistical landslide model is based on an improved landslide susceptibility map of China and a rainfall intensity–duration threshold. First, it is driven by observed rainfall and RegCM4.0 rainfall in 1980–99, and it can reproduce the spatial distribution of landslides in China pretty ***, it is used to forecast the landslide changes over China in the future under the RCP8.5 scenario. The results consistently reveal that landslides will increase significantly in most areas of China, especially in the southeastern, northeastern, and western parts of Northwest China. The change pattern at the end of the 21 st century is generally consistent with that in the middle of the 21 st century, but with larger increment and magnitude. In terms of the probability,the proportion of grid points that are very likely and extremely likely to experience landslides will also increase.

关键词： landslides projection statistical landslide forecasting model regional climate model

瑞马唑仑与丙泊酚用于双眼斜视矫正日间手术患儿全身麻醉的效果比较

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中华医学杂志 2024年第29期104卷 2728-2733页

作者：陈红芽王惠军奚春花王月陈一萌张丛雅王影王古岩首都医科大学附属北京同仁医院麻醉科北京

目的比较瑞马唑仑与丙泊酚用于双眼斜视矫正日间手术患儿全身麻醉的效果。方法前瞻性纳入2021年12月至2022年5月于北京同仁医院接受择期喉罩全身麻醉双眼斜视矫正日间手术的患儿60例, 美国麻醉医师协会(ASA)分级Ⅰ～Ⅱ级。采用SPSS随机... 详细信息

目的比较瑞马唑仑与丙泊酚用于双眼斜视矫正日间手术患儿全身麻醉的效果。方法前瞻性纳入2021年12月至2022年5月于北京同仁医院接受择期喉罩全身麻醉双眼斜视矫正日间手术的患儿60例, 美国麻醉医师协会(ASA)分级Ⅰ～Ⅱ级。采用SPSS随机化程序按照1∶1比例将患儿随机分配到瑞马唑仑组和丙泊酚组, 每组30例。瑞马唑仑组给予瑞马唑仑、瑞芬太尼及米库氯铵诱导, 瑞马唑仑和瑞芬太尼麻醉维持。丙泊酚组给予丙泊酚、瑞芬太尼及米库氯铵诱导, 丙泊酚和瑞芬太尼麻醉维持。瑞马唑仑组术毕3 min给予患儿氟马西尼0.1 mg拮抗, 丙泊酚组等待患儿自然苏醒。主要观察指标为术毕停药到拔除喉罩所需时间;次要观察指标包括诱导期给药到患者意识消失所需时间、术中血流动力学指标[平均动脉压(MAP)和心率]、镇静成功率、术中知晓率、麻醉后恢复室(PACU)不良反应发生率等。结果瑞马唑仑组男12例, 女18例, 年龄(5.0±1.4)岁。丙泊酚组男14例, 女16例, 年龄(5.3±1.3)岁。瑞马唑仑组患儿术毕停药到拔除喉罩所需时间为(6.5±1.2)min, 短于丙泊酚组的(10.7±1.9)min(P0.05)。结论对于接受双眼斜视矫正日间手术患儿, 采用瑞马唑仑进行全身麻醉在不增加术后不良反应发生率的情况下, 可缩短术毕停药至拔除喉罩所需时间, 且术中血流动力学更稳定。

关键词：儿童瑞马唑仑丙泊酚氟马西尼斜视

The increase of snowfall in Northeast China after the mid-1980s

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Chinese Science Bulletin 2013年第12期58卷 1350-1354页

作者： wang huijun ShengPing Nansen-Zhu International Research Center Institute of Atmospheric Physics Chinese Academy of Sciences Climate Change Research Center Chinese Academy of Sciences Graduate University of Chinese Academy of Sciences

We studied long-term variation of winter snowfall in Northeast China (NEC) for 1951-2010. Results show that NEC snowfall increased about 20% during 1986-2010 relative to 1951-1985. Further investigation suggests that the snowfall increase is closely associated with weakening of the East Asian winter monsoon (EAWM). The physical processes were portrayed by this research. Weakening of EAWM led to weakened cold air flow from the north, thus resulted in the warming of the surface ocean along the Northeast Asia coast and more water vapor evaporated from the ocean surface to the atmosphere and further transported to NEC. Also, because of EAWM weakening, more water vapor from south, east and west of NEC was transported to NEC, increasing water vapor content and hence snowfall there. From an atmospheric circulation viewpoint, EAWM weakening strengthened convergence at low levels and divergence at high levels, thereby favoring increased vertical convection and snowfall.

关键词：中国东北地区降雪东亚冬季风中期年代海洋表面水汽含量大气环流

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

Dominant Modes of Interannual Variability in Atmospheric Water Vapor Content over East Asia during Winter and Their Associated Mechanisms

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Advances in Atmospheric Sciences 2021年第10期38卷 1706-1722页

作者： Wenyue HE Bo SUN huijun wang Nansen-Zhu International Research Centre Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China 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 Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519080China

Atmospheric water vapor content(WVC)is a critical factor for East Asian winter *** study investigates the dominant modes of interannual variability in WVC over East Asia during winter and their underlying *** on the empirical orthogonal function(EOF)method,the leading mode(EOF1,R2=28.9%)of the interannual variability in the East Asian winter WVC exhibits a meridional dipole pattern characterized by opposite WVC anomalies over northeastern China and eastern China;the second mode(EOF2,R2=24.3%)of the interannual variability in the East Asian winter WVC exhibits a monopole pattern characterized by consistent WVC anomalies over eastern ***1 is mainly modulated by two anomalous zonal water vapor transport(WVT)branches over northeastern China and eastern China,which are associated with an anomalous atmospheric wave train over Eurasia affected by sea ice cover in the Kara Sea-Barents Sea(SIC-KSBS)area in the preceding October-November(ON).EOF2 is mainly modulated by an anomalous westerly WVT branch over eastern China,which is associated with a circumglobal atmospheric zonal wave train in the Northern *** circumglobal zonal wave train is modulated by concurrent central and eastern tropical Pacific sea surface temperature *** SIC-KSBS anomalies in ON and the concurrent SST anomalies over tropical Pacific may partially account for the interannual variability of EOF1 and EOF2 winter WVC,and thus may provide a theoretical basis for improving the prediction of winter climate over East Asia.

关键词： interannual variability leading modes watervapor content East Asia

Solar-wind–magnetosphere energy influences the interannual variability of the northern-hemispheric winter climate

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National Science Review 2020年第1期7卷 141-148页

作者： Shengping He huijun wang Fei Li Hui Li Chi wang Geophysical Institute University of Bergen and Bjerknes Center for Climate Research Key Laboratory of Meteorological Disaster/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science and Technology Climate Change Research Center Chinese Academy of Sciences Nansen-Zhu International Research Centre Institute of Atmospheric Physics Chinese Academy of Sciences Norwegian Institute for Air Research State Key Laboratory of Space Weather National Space Science Center Chinese Academy of Sciences

Solar irradiance has been universally acknowledged to be dominant by quasi-decadal variability, which has been adopted frequently to investigate its effect on climate decadal variability. As one major terrestrial energy source, solar-wind energy flux into Earth’s magnetosphere(Ein) exhibits dramatic interannual variation, the effect of which on Earth’s climate, however, has not drawn much attention. Based on the Einestimated by 3D magnetohydrodynamic simulations, we demonstrate a novelty that the annual mean Eincan explain up to 25% total interannual variance of the northern-hemispheric temperature in the subsequent boreal winter. The concurrent anomalous atmospheric circulation resembles the positive phase of Arctic Oscillation/North Atlantic Oscillation. The warm anomalies in the tropic stratopause and tropopause induced by increased solar-wind–magnetosphere energy persist into the subsequent *** to the dominant change in the polar vortex and mid-latitude westerly in boreal winter, a ‘top-down’propagation of the stationary planetary wave emerges in the Northern Hemisphere and further influences the atmospheric circulation and climate.

关键词： solar wind winter climate interannual variability stratosphere

Can the climate background of western North Pacific typhoon activity be predicted by climate model?

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Chinese Science Bulletin 2008年第15期53卷 2392-2399页

作者： LANG XianMei wang huijun Center for Disastrous Climate Research and Prediction & Nansen-Zhu International Research Center Institute of AtmosphericPhysics Chinese Academy of Sciences Beijing 100029 China

Based on the observation and reanalysis data through 1948―2004, the vertical shear of zonal wind, outgoing longwave radiation, and divergence fields in the lower and upper troposphere during summer are revealed to correlate significantly with the concurrent western North Pacific (WNP) typhoon fre-quency, and they therefore can be regarded as predictors for the WNP typhoon activity anomaly. After that, the 34-year (1970―2003) ensemble hindcast experiments are performed by the nine-level atmos-pheric general circulation model developed at the Institute of Atmospheric Physics Under the Chinese Academy of Sciences (IAP9L-AGCM), aiming to investigate the numerical predictability of the summer vertical shear of zonal wind and divergence field in the lower troposphere. It is found that the temporal correlation coefficients between the hindcast and observation are 0.70 and 0.62 for the vertical shear of zonal wind and divergence field, respectively. This suggests that the model possesses a large potential skill for predicting the large-scale climate background closely related to the WNP typhoon activity, and the model is therefore capable of performing the real-time numerical prediction of the WNP typhoon activity anomaly to some extent.

关键词：西北太平洋台风频繁度 IAP9L-AGCM 可预测性