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Optimizing the key parameter to accelerate the recovery of AMOC under a rapid increase of greenhouse gas forcing
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作者 Haolan Ren fei zheng +1 位作者 Tingwei Cao Qiang Wang 《Atmospheric and Oceanic Science Letters》 2025年第1期39-45,共7页
Atlantic Meridional Overturning Circulation(AMOC)plays a central role in long-term climate variations through its heat and freshwater transports,which can collapse under a rapid increase of greenhouse gas forcing in c... Atlantic Meridional Overturning Circulation(AMOC)plays a central role in long-term climate variations through its heat and freshwater transports,which can collapse under a rapid increase of greenhouse gas forcing in climate models.Previous studies have suggested that the deviation of model parameters is one of the major factors in inducing inaccurate AMOC simulations.In this work,with a low-resolution earth system model,the authors try to explore whether a reasonable adjustment of the key model parameter can help to re-establish the AMOC after its collapse.Through a new optimization strategy,the extra freshwater flux(FWF)parameter is determined to be the dominant one affecting the AMOC’s variability.The traditional ensemble optimal interpolation(EnOI)data assimilation and new machine learning methods are adopted to optimize the FWF parameter in an abrupt 4×CO_(2) forcing experiment to improve the adaptability of model parameters and accelerate the recovery of AMOC.The results show that,under an abrupt 4×CO_(2) forcing in millennial simulations,the AMOC will first collapse and then re-establish by the default FWF parameter slowly.However,during the parameter adjustment process,the saltier and colder sea water over the North Atlantic region are the dominant factors in usefully improving the adaptability of the FWF parameter and accelerating the recovery of AMOC,according to their physical relationship with FWF on the interdecadal timescale. 展开更多
关键词 Recovery of AMOC 4×CO_(2) forcing Key parameter Parameter estimation Data assimilation Machine learning
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PD-1抑制剂联合化疗对比贝伐珠单抗联合化疗一线治疗非鳞非小细胞肺癌的研究 被引量:7
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作者 郑飞 李曙光 +2 位作者 黄芳 史健 刘义冰 《中国肿瘤临床》 CAS CSCD 北大核心 2024年第15期769-774,共6页
目的比较细胞程序性死亡受体-1(programmed cell death protein-1,PD-1)抑制剂联合化疗与贝伐珠单抗联合化疗一线治疗晚期非鳞非小细胞肺癌(non-squamous non-small cell lung cancer,nsNSCLC)的疗效。方法回顾性收集2014年11月至2024年... 目的比较细胞程序性死亡受体-1(programmed cell death protein-1,PD-1)抑制剂联合化疗与贝伐珠单抗联合化疗一线治疗晚期非鳞非小细胞肺癌(non-squamous non-small cell lung cancer,nsNSCLC)的疗效。方法回顾性收集2014年11月至2024年3月于河北医科大学第四医院接受一线治疗的晚期nsNSCLC患者237例。根据治疗方案分为PD-1抑制剂联合化疗(IC组)119例和贝伐珠单抗联合化疗(BC组)118例。采用倾向得分匹配(propensity score matching,PSM)平衡协变量。研究主要终点为无进展生存期(progression-free survival,PFS),次要终点为客观缓解率(objective response rate,ORR)、疾病控制率(disease control rate,DCR)、总生存期(overall survival,OS)。结果237例患者经PSM后IC组和BC组各87例,IC组和BC组的ORR分别为31.0%(27/87)和43.7%(38/87)(P=0.085),DCR为96.6%(84/87)和95.4%(83/87)(P=1.000)。中位PFS IC组为9.3个月,BC组为9.1个月,两组差异无统计学意义(P=0.053)。OS两组差异无统计学意义(两组均未达到中位OS,P=0.116)。结论PD-1抑制剂联合化疗对比贝伐珠单抗联合化疗一线治疗晚期nsNSCLC近期疗效无差异。 展开更多
关键词 PD-1抑制剂 贝伐珠单抗 非鳞非小细胞肺癌
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Influence of Winter Tasman Sea SST on the Antarctic Peninsula:A Perspective from Historical Simulations
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作者 Rui WANG fei zheng Hao WANG 《Advances in Atmospheric Sciences》 2025年第8期1533-1547,共15页
The winter temperature variability of the Antarctic Peninsula(AP)has been proven to be influenced by sea surface temperature(SST)anomalies over the Tasman Sea.Using outputs over an extended time period from historical... The winter temperature variability of the Antarctic Peninsula(AP)has been proven to be influenced by sea surface temperature(SST)anomalies over the Tasman Sea.Using outputs over an extended time period from historical experiments,the skills of CMIP6 models in simulating the atmospheric responses to Tasman Sea SST are evaluated in this study,with an emphasis on the relationships with AP temperatures.The spatial correlation coefficient and normalized standard deviation are used as the evaluation metrics.Corresponding results suggest that the majority of CMIP6 models can capture the basic spatial distributions of Tasman Sea-related teleconnections across the Southern Hemisphere extratropical region,featuring a Pacific–South America-like pattern.However,the overestimation of atmospheric interannual variability and the underestimation of oceanic interannual variability in CMIP6 models result in a considerable amplification of the atmospheric responses to SST anomalies.The model uncertainty in depicting the relationships between Tasman Sea SSTs and AP surface temperatures,as well as the associated teleconnections,can partially be attributed to variations in grid resolutions among models.Additionally,further analysis of the Antarctic sea ice shows that the Tasman Sea SST may contribute to the interannual variability of the Antarctic dipole in CMIP6. 展开更多
关键词 historical experiment CMIP6 model evaluation Tasman Sea Antarctic Peninsula TELECONNECTION
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Black Phosphorus and E7-Functionalized Sulfonated Polyetheretherketone with Effective Osteogenicity and Antibacterial Activity
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作者 Xiao Wang Shuning Zhang +7 位作者 Ai Zhu Lingyan Cao Long Xu Junjie Wang fei zheng Xiangkai Zhang Hongyan Chen Xinquan Jiang 《Engineering》 2025年第3期147-161,共15页
Given its excellent biological properties and the matching of its elastic modulus with that of human bone tissue,medical polyetheretherketone(PEEK)is considered a desirable candidate for bone-implant materials.However... Given its excellent biological properties and the matching of its elastic modulus with that of human bone tissue,medical polyetheretherketone(PEEK)is considered a desirable candidate for bone-implant materials.However,its poor osseointegrative and antibacterial properties greatly limit its clinical application.To address these concerns,a functional PEEK implant is needed.Herein,a novel photo-responsive multifunctional PEEK-based implant material(sPEEK/BP/E7)with both effective osteogenesis and good disinfection properties was constructed via the self-assembly of black phosphorus(BP)nanosheets,mussel-inspired polydopamine(PDA),and bioactive short peptide E7 on sulfonated PEEK(sPEEK).The versatile micro-/nano-structured PEEK surface provides superior hydrophilicity,a favorable osteogenic microenvironment,and excellent photothermal effects under near-infrared(NIR)irradiation.The in vitro results showed that sPEEK/BP/E7 displays enhanced cytocompatibility and osteogenicity in terms of cell adhesion,proliferation,alkaline phosphatase(ALP)activity,matrix mineralization,and osteogenesis-related gene expression,superior to those of the sPEEK and sPEEK/BP samples.In addition to osteogenesis,the multifunctional coating exhibited strong antibacterial activity against both Staphylococcus aureus(S.aureus)and Escherichia coli(E.coli).Furthermore,it was confirmed in a rat femoral infection model that sPEEK/BP/E7 effectively resisted infection caused by S.aureus under NIR light irradiation and promoted osseointegration in vivo.Thus,this work presents a facile strategy to realize improvement of the“functional integration”of new polymer bone–implant materials and provide new ideas for their clinical application. 展开更多
关键词 POLYETHERETHERKETONE Black phosphorus nanosheets E7 peptides Stem cell recruitment Osteogenesis Antibacterial
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Record High Temperatures in the Ocean in 2024
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作者 Lijing CHENG John ABRAHAM +51 位作者 Kevin E.TRENBERTH James REAGAN Huai-Min ZHANG Andrea STORTO Karina VON SCHUCKMANN Yuying PAN Yujing ZHU Michael E.MANN Jiang ZHU Fan WANG Fujiang YU Ricardo LOCARNINI John FASULLO Boyin HUANG Garrett GRAHAM Xungang YIN Viktor GOURETSKI fei zheng Yuanlong LI Bin ZHANG Liying WAN Xingrong CHEN Dakui WANG Licheng FENG Xiangzhou SONG Yulong LIU Franco RESEGHETTI Simona SIMONCELLI Gengxin CHEN Rongwang ZHANG Alexey MISHONOV Zhetao TAN Wangxu WEI Huifeng YUAN Guancheng LI Qiuping REN Lijuan CAO Yayang LU Juan DU Kewei LYU Albertus SULAIMAN Michael MAYER Huizan WANG Zhanhong MA Senliang BAO Henqian YAN Zenghong LIU Chunxue YANG Xu LIU Zeke HAUSFATHER Tanguy SZEKELY Flora GUES 《Advances in Atmospheric Sciences》 2025年第6期1092-1109,共18页
Heating in the ocean has continued in 2024 in response to increased greenhouse gas concentrations in the atmosphere,despite the transition from an El Ni?o to neutral conditions. In 2024, both global sea surface temper... Heating in the ocean has continued in 2024 in response to increased greenhouse gas concentrations in the atmosphere,despite the transition from an El Ni?o to neutral conditions. In 2024, both global sea surface temperature(SST) and upper2000 m ocean heat content(OHC) reached unprecedented highs in the historical record. The 0–2000 m OHC in 2024exceeded that of 2023 by 16 ± 8 ZJ(1 Zetta Joules = 1021 Joules, with a 95% confidence interval)(IAP/CAS data), which is confirmed by two other data products: 18 ± 7 ZJ(CIGAR-RT reanalysis data) and 40 ± 31 ZJ(Copernicus Marine data,updated to November 2024). The Indian Ocean, tropical Atlantic, Mediterranean Sea, North Atlantic, North Pacific, and Southern Ocean also experienced record-high OHC values in 2024. The global SST continued its record-high values from2023 into the first half of 2024, and declined slightly in the second half of 2024, resulting in an annual mean of 0.61°C ±0.02°C(IAP/CAS data) above the 1981–2010 baseline, slightly higher than the 2023 annual-mean value(by 0.07°C ±0.02°C for IAP/CAS, 0.05°C ± 0.02°C for NOAA/NCEI, and 0.06°C ± 0.11°C for Copernicus Marine). The record-high values of 2024 SST and OHC continue to indicate unabated trends of global heating. 展开更多
关键词 ocean heat content sea surface temperature ocean temperature global warming CLIMATE
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水轮机转轮与止漏环扫膛故障的分析与修复
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作者 费征 武许杰 +1 位作者 王华 王永峰 《水电与新能源》 2025年第10期68-71,共4页
本文针对丹江口水电厂1号机组在检修中发现的转轮与顶盖、底环在止漏环间的扫膛问题,结合设备检修数据与运行分析结果,探讨了扫膛的成因,提出了针对性的修复方案,并建议了改进措施以提高设备运行的可靠性。文章旨在为水轮发电机组的运... 本文针对丹江口水电厂1号机组在检修中发现的转轮与顶盖、底环在止漏环间的扫膛问题,结合设备检修数据与运行分析结果,探讨了扫膛的成因,提出了针对性的修复方案,并建议了改进措施以提高设备运行的可靠性。文章旨在为水轮发电机组的运行维护和优化设计提供参考。 展开更多
关键词 止漏环 转轮 扫膛 修复
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Chemical composition,biological activities and product development of Gastrodia elata:a review
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作者 Liankui Wen Yuchen Jiang +5 位作者 Wenqi Wang Rongchen Zhu Jiahua Liu Yang He fei zheng Yuzhu Wu 《Food Science and Human Wellness》 2025年第10期3796-3820,共25页
Gastrodia elata Blume has a rich history of use in Asian.However,there is still a need for systematic analysis regarding the relationship and in-depth development between its components and functions.Through comprehen... Gastrodia elata Blume has a rich history of use in Asian.However,there is still a need for systematic analysis regarding the relationship and in-depth development between its components and functions.Through comprehensive analysis utilizing databases such as Pub Med,Web of Science,and Google Scholar,the practical components,biological activities,and product development of G.elata have been investigated.It has been found that the main active components of G.elata,such as gastrodin and G.elata polysaccharides,possess functionalities in improving conditions such as epilepsy,hypertension,and osteoporosis.These active components exhibit phenolic hydroxyl groups,molecular weight,conformation,and spatial arrangement,contributing to their enhanced ability to scavenge free radicals.Additionally,G.elata is known to have organic acids and esters,which exhibit potential immune regulatory and antiviral properties.Compounds with multiple acidic functional groups exhibit even more vigorous activity.Steroidal compounds likeβ-sitosterol,due to their presence of alcohol and ketone groups,along with a multi-ring structure,exhibit superior cholesterol-lowering activity.G.elata has already been recognized in the traditional chinese medicine and food homology list,showcasing its potential for development in line with the health demands of the current era.However,challenges regarding quality evaluation,peculiar odor,and the extraction process of the practical components still require immediate attention.Constructing a robust evaluation system and optimizing product processing techniques will be crucial for the future advancement of the G.elata industry. 展开更多
关键词 Gastrodia elata Blume Chemical components Biological activities Product analysis
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丹江口大坝析钙现象分析及治理
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作者 费征 武许杰 +1 位作者 王华 王永峰 《水电与新能源》 2025年第10期79-81,共3页
混凝土大坝析钙会导致混凝土质量下降、大坝渗漏量增大以及钢筋锈蚀等后果,严重影响到大坝的稳定和安全。基于丹江口大坝析钙的具体表现和相关文献的研究,总结了析钙对大坝结构稳定性及耐久性的危害,针对性地提出了防治大坝析钙的综合措... 混凝土大坝析钙会导致混凝土质量下降、大坝渗漏量增大以及钢筋锈蚀等后果,严重影响到大坝的稳定和安全。基于丹江口大坝析钙的具体表现和相关文献的研究,总结了析钙对大坝结构稳定性及耐久性的危害,针对性地提出了防治大坝析钙的综合措施,包括:优化混凝土配合比,增强混凝土密实性,改善大坝排水系统,对混凝土表面进行清理和防护,加强大坝监测与维护等,以确保大坝的安全运行。 展开更多
关键词 析钙现象 危害与治理 防护措施
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原油破乳剂的作用机理及研究进展 被引量:3
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作者 朱航 袁海洋 +3 位作者 王庆慧 郑飞 张哲玮 吴飞跃 《化学工程与技术》 CAS 2019年第3期254-259,共6页
本文首先简要回顾了原油破乳剂的发展历程,然后对影响乳状液稳定的影响因素进行了分析,从而阐述了原油破乳剂的作用机理,接着对原油破乳的主要类型及其应用特点进行了综述,最后对原油破乳剂的发展进行了展望。
关键词 原油 破乳剂 作用机理 复配 应用
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Pathways of Influence of the Northern Hemisphere Mid–high Latitudes on East Asian Climate: A Review 被引量:40
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作者 Jianping LI fei zheng +2 位作者 Cheng SUN Juan FENG Jing WANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2019年第9期902-921,共20页
This paper reviews recent progress made by Chinese scientists on the pathways of influence of the Northern Hemisphere mid-high latitudes on East Asian climate within the framework of a“coupled oceanic-atmospheric(lan... This paper reviews recent progress made by Chinese scientists on the pathways of influence of the Northern Hemisphere mid-high latitudes on East Asian climate within the framework of a“coupled oceanic-atmospheric(land-atmospheric or seaice-atmospheric)bridge”and“chain coupled bridge”.Four major categories of pathways are concentrated upon,as follows:Pathway A—from North Atlantic to East Asia;Pathway B—from the North Pacific to East Asia;Pathway C—from the Arctic to East Asia;and Pathway D—the synergistic effects of the mid-high latitudes and tropics.In addition,definitions of the terms“combined effect”,“synergistic effect”and“antagonistic effect”of two or more factors of influence or processes and their criteria are introduced,so as to objectively investigate those effects in future research. 展开更多
关键词 East Asian climate Northern HEMISPHERE mid-high LATITUDES COUPLED oceanic-land-sea-ice-atmospheric BRIDGE chain COUPLED BRIDGE pathway synergistic effect
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基于模糊聚类的多视图协同过滤推荐算法 被引量:1
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作者 黄巧文 周宽久 +1 位作者 费铮 崔云鹏 《计算机技术与发展》 2023年第8期14-22,共9页
传统的协同过滤推荐算法在面对多源异构数据时推荐效果差、执行效率低,且难以挖掘用户的关键行为。针对这种情况,提出基于模糊聚类的多视图协同过滤推荐算法。该算法旨在收集用户的多种行为偏好来构建多视图数据,并通过对每种行为进行... 传统的协同过滤推荐算法在面对多源异构数据时推荐效果差、执行效率低,且难以挖掘用户的关键行为。针对这种情况,提出基于模糊聚类的多视图协同过滤推荐算法。该算法旨在收集用户的多种行为偏好来构建多视图数据,并通过对每种行为进行加权来挖掘多种行为之间的关联信息,提取关键行为信息,进而提升推荐效果。为提高推荐结果的精确度,利用多个视图的行为权重和偏好值,提出项目的加权相似性度量方法,同时引入项目同现矩阵以进一步提高相似性度量的准确性。为优化相似项目的搜索空间,结合多视图聚类的思想,在传统模糊聚类方法的基础上引入质心约束和最大熵理论,提出一种基于质心约束的多视图熵加权模糊聚类算法。此外,为提高算法对非线性数据的处理能力,引入核映射技术将线性不可分的低维特征映射到高维核空间使其变得线性可分,从而提出一种基于质心约束的多视图加权核模糊聚类算法。在与较先进的基于聚类的协同过滤推荐算法的比较实验中,所提算法的平均绝对误差提升了1.95百分点,召回命中率提升了1.54百分点。实验结果表明,所提算法有效地提升了推荐结果的命中率和准确性。 展开更多
关键词 协同过滤 多视图聚类 最大熵方法 推荐算法 模糊聚类
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Extreme Cold Events in North America and Eurasia in November-December 2022: A Potential Vorticity Gradient Perspective 被引量:13
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作者 Yao YAO Wenqin ZHUO +8 位作者 Zhaohui GONG Binhe LUO Dehai LUO fei zheng Linhao ZHONG fei HUANG Shuangmei MA Congwen ZHU Tianjun ZHOU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2023年第6期953-962,I0002-I0005,共14页
From 17 November to 27 December 2022, extremely cold snowstorms frequently swept across North America and Eurasia. Diagnostic analysis reveals that these extreme cold events were closely related to the establishment o... From 17 November to 27 December 2022, extremely cold snowstorms frequently swept across North America and Eurasia. Diagnostic analysis reveals that these extreme cold events were closely related to the establishment of blocking circulations. Alaska Blocking(AB) and subsequent Ural Blocking(UB) episodes are linked to the phase transition of the North Atlantic Oscillation(NAO) and represent the main atmospheric regimes in the Northern Hemisphere. The downstream dispersion and propagation of Rossby wave packets from Alaska to East Asia provide a large-scale connection between AB and UB episodes. Based on the nonlinear multi-scale interaction(NMI) model, we found that the meridional potential vorticity gradient(PVy) in November and December of 2022 was anomalously weak in the mid-high latitudes from North America to Eurasia and provided a favorable background for the prolonged maintenance of UB and AB events and the generation of associated severe extreme snowstorms. However, the difference in the UB in terms of its persistence,location, and strength between November and December is related to the positive(negative) NAO in November(December). During the La Ni?a winter of 2022, the UB and AB events are related to the downward propagation of stratospheric anomalies, in addition to contributions by La Ni?a and low Arctic sea ice concentrations as they pertain to reducing PVyin mid-latitudes. 展开更多
关键词 successive cold extremes atmospheric blocking NAO potential vorticity gradient water vapor backward tracking Arctic sea ice La Niña
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The 2020/21 Extremely Cold Winter in China Influenced by the Synergistic Effect of La Niña and Warm Arctic 被引量:16
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作者 fei zheng Yuan YUAN +8 位作者 Yihui DING Kexin LI Xianghui FANG Yuheng ZHAO Yue SUN Jiang ZHU Zongjian KE Ji WANG Xiaolong JIA 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2022年第4期546-552,共7页
In the first half of winter 2020/21,China has experienced an extremely cold period across both northern and southern regions,with record-breaking low temperatures set in many stations of China.Meanwhile,a moderate La ... In the first half of winter 2020/21,China has experienced an extremely cold period across both northern and southern regions,with record-breaking low temperatures set in many stations of China.Meanwhile,a moderate La Niña event which exceeded both oceanic and atmospheric thresholds began in August 2020 and in a few months developed into its mature phase,just prior to the 2020/21 winter.In this report,the mid−high-latitude large-scale atmospheric circulation anomalies in the Northern Hemisphere,which were forced by the negative phase of Arctic Oscillation,a strengthened Siberian High,an intensified Ural High and a deepened East Asian Trough,are considered to be the direct reason for the frequent cold surges in winter 2020/21.At the same time,the synergistic effect of the warm Arctic and the cold tropical Pacific(La Niña)provided an indispensable background,at a hemispheric scale,to intensify the atmospheric circulation anomalies in middle-to-high latitudes.In the end,a most recent La Niña prediction is provided and the on-coming evolution of climate is discussed for the remaining part of the 2020/21 winter for the purpose of future decision-making and early warning. 展开更多
关键词 extremely cold winter anomalous atmospheric circulation synergistic effect La Niña warm Arctic
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The Seasonal Prediction of the Exceptional Yangtze River Rainfall in Summer 2020 被引量:11
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作者 Chaofan LI Riyu LU +3 位作者 Nick DUNSTONE Adam ASCAIFE Philip EBETT fei zheng 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2021年第12期2055-2066,共12页
During June and July of 2020,the Yangtze River basin suffered from extreme mei-yu rainfall and catastrophic flooding.This study explores the seasonal predictability and associated dynamical causes for this extreme Yan... During June and July of 2020,the Yangtze River basin suffered from extreme mei-yu rainfall and catastrophic flooding.This study explores the seasonal predictability and associated dynamical causes for this extreme Yangtze River rainfall event,based on forecasts from the Met Office GloSea5 operational forecast system.The forecasts successfully predicted above-average rainfall over the Yangtze River basin,which arose from the successful reproduction of the anomalous western North Pacific subtropical high(WNPSH).Our results indicate that both the Indian Ocean warm sea surface temperature(SST)and local WNP SST gradient were responsible for the westward extension of the WNPSH,and the forecasts captured these tropical signals well.We explore extratropical drivers but find a large model spread among the forecast members regarding the meridional displacements of the East Asian mid-latitude westerly jet(EAJ).The forecast members with an evident southward displacement of the EAJ favored more extreme Yangtze River rainfall.However,the forecast Yangtze River rainfall anomaly was weaker compared to that was observed and no member showed such strong rainfall.In observations,the EAJ displayed an evident acceleration in summer 2020,which could lead to a significant wind convergence in the lower troposphere around the Yangtze River basin,and favor more mei-yu rainfall.The model forecast failed to satisfactorily reproduce these processes.This difference implies that the observed enhancement of the EAJ intensity gave a large boost to the Yangtze River rainfall,hindering a better forecast of the intensity of the event and disaster mitigation. 展开更多
关键词 seasonal forecast Yangtze River rainfall western North Pacific subtropical high westerly jet
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ENSO Frequency Asymmetry and the Pacific Decadal Oscillation in Observations and 19 CMIP5 Models 被引量:10
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作者 Renping LIN fei zheng Xiao DONG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2018年第5期495-506,共12页
Using observational data and the pre-industrial simulations of 19 models from the Coupled Model Intercomparison Project Phase 5(CMIP5), the El Ni o(EN) and La Ni a(LN) events in positive and negative Pacific Dec... Using observational data and the pre-industrial simulations of 19 models from the Coupled Model Intercomparison Project Phase 5(CMIP5), the El Ni o(EN) and La Ni a(LN) events in positive and negative Pacific Decadal Oscillation(PDO) phases are examined. In the observational data, with EN(LN) events the positive(negative) SST anomaly in the equatorial eastern Pacific is much stronger in positive(negative) PDO phases than in negative(positive) phases. Meanwhile,the models cannot reasonably reproduce this difference. Besides, the modulation of ENSO frequency asymmetry by the PDO is explored. Results show that, in the observational data, EN is 300% more(58% less) frequent than LN in positive(negative)PDO phases, which is significant at the 99% confidence level using the Monte Carlo test. Most of the CMIP5 models exhibit results that are consistent with the observational data. 展开更多
关键词 ENSO frequency asymmetry Pacific Decadal Oscillation decadal variation Monte Carlo method CM1P5
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Influence of the NAO on Wintertime Surface Air Temperature over East Asia:Multidecadal Variability and Decadal Prediction 被引量:6
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作者 Jianping LI Tiejun XIE +5 位作者 Xinxin TANG Hao WANG Cheng SUN Juan FENG fei zheng Ruiqiang DING 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2022年第4期625-642,共18页
In this paper,we investigate the influence of the winter NAO on the multidecadal variability of winter East Asian surface air temperature(EASAT)and EASAT decadal prediction.The observational analysis shows that the wi... In this paper,we investigate the influence of the winter NAO on the multidecadal variability of winter East Asian surface air temperature(EASAT)and EASAT decadal prediction.The observational analysis shows that the winter EASAT and East Asian minimum SAT(EAmSAT)display strong in-phase fluctuations and a significant 60-80-year multidecadal variability,apart from a long-term warming trend.The winter EASAT experienced a decreasing trend in the last two decades,which is consistent with the occurrence of extremely cold events in East Asia winters in recent years.The winter NAO leads the detrended winter EASAT by 12-18 years with the greatest significant positive correlation at the lead time of 15 years.Further analysis shows that ENSO may affect winter EASAT interannual variability,but does not affect the robust lead relationship between the winter NAO and EASAT.We present the coupled oceanic-atmospheric bridge(COAB)mechanism of the NAO influences on winter EASAT multidecadal variability through its accumulated delayed effect of~15 years on the Atlantic Multidecadal Oscillation(AMO)and Africa-Asia multidecadal teleconnection(AAMT)pattern.An NAO-based linear model for predicting winter decadal EASAT is constructed on the principle of the COAB mechanism,with good hindcast performance.The winter EASAT for 2020-34 is predicted to keep on fluctuating downward until~2025,implying a high probability of occurrence of extremely cold events in coming winters in East Asia,followed by a sudden turn towards sharp warming.The predicted 2020/21 winter EASAT is almost the same as the 2019/20 winter. 展开更多
关键词 winter East Asian surface air temperature North Atlantic Oscillation Atlantic Multidecadal Oscillation Africa-Asia multidecadal teleconnection pattern coupled oceanic-atmospheric bridge multidecadal variability
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The Predictability of Ocean Environments that Contributed to the 2020/21 Extreme Cold Events in China:2020/21 La Niña and 2020 Arctic Sea Ice Loss 被引量:8
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作者 fei zheng Ji-Ping LIU +6 位作者 Xiang-Hui FANG Mi-Rong SONG Chao-Yuan YANG Yuan YUAN Ke-Xin LI Ji WANG Jiang ZHU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2022年第4期658-675,共18页
Several consecutive extreme cold events impacted China during the first half of winter 2020/21,breaking the low-temperature records in many cities.How to make accurate climate predictions of extreme cold events is sti... Several consecutive extreme cold events impacted China during the first half of winter 2020/21,breaking the low-temperature records in many cities.How to make accurate climate predictions of extreme cold events is still an urgent issue.The synergistic effect of the warm Arctic and cold tropical Pacific has been demonstrated to intensify the intrusions of cold air from polar regions into middle-high latitudes,further influencing the cold conditions in China.However,climate models failed to predict these two ocean environments at expected lead times.Most seasonal climate forecasts only predicted the 2020/21 La Niña after the signal had already become apparent and significantly underestimated the observed Arctic sea ice loss in autumn 2020 with a 1-2 month advancement.In this work,the corresponding physical factors that may help improve the accuracy of seasonal climate predictions are further explored.For the 2020/21 La Niña prediction,through sensitivity experiments involving different atmospheric-oceanic initial conditions,the predominant southeasterly wind anomalies over the equatorial Pacific in spring of 2020 are diagnosed to play an irreplaceable role in triggering this cold event.A reasonable inclusion of atmospheric surface winds into the initialization will help the model predict La Niña development from the early spring of 2020.For predicting the Arctic sea ice loss in autumn 2020,an anomalously cyclonic circulation from the central Arctic Ocean predicted by the model,which swept abnormally hot air over Siberia into the Arctic Ocean,is recognized as an important contributor to successfully predicting the minimum Arctic sea ice extent. 展开更多
关键词 extreme cold event PREDICTABILITY La Niña Arctic sea ice loss
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Contrasting the Skills and Biases of Deterministic Predictions for the Two Types of El Nio 被引量:5
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作者 fei zheng Jin-Yi YU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2017年第12期1395-1403,共9页
The tropical Pacific has begun to experience a new type of El Nio, which has occurred particularly frequently during the last decade, referred to as the central Pacific(CP) El Nio. Various coupled models with differen... The tropical Pacific has begun to experience a new type of El Nio, which has occurred particularly frequently during the last decade, referred to as the central Pacific(CP) El Nio. Various coupled models with different degrees of complexity have been used to make real-time El Nio predictions, but high uncertainty still exists in their forecasts. It remains unknown as to how much of this uncertainty is specifically related to the new CP-type El Nio and how much is common to both this type and the conventional Eastern Pacific(EP)-type El Nio. In this study, the deterministic performance of an El Nio–Southern Oscillation(ENSO) ensemble prediction system is examined for the two types of El Nio. Ensemble hindcasts are run for the nine EP El Nio events and twelve CP El Nio events that have occurred since 1950. The results show that(1) the skill scores for the EP events are significantly better than those for the CP events, at all lead times;(2) the systematic forecast biases come mostly from the prediction of the CP events; and(3) the systematic error is characterized by an overly warm eastern Pacific during the spring season, indicating a stronger spring prediction barrier for the CP El Nio. Further improvements to coupled atmosphere–ocean models in terms of CP El Nio prediction should be recognized as a key and high-priority task for the climate prediction community. 展开更多
关键词 ENSO EP El Nio CP El Nio prediction skill systematic bias spring prediction barrier
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Evaluation of the Tropical Variability from the Beijing Climate Center's Real-Time Operational Global Ocean Data Assimilation System 被引量:5
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作者 Wei ZHOU Mengyan CHEN +4 位作者 Wei ZHUANG Fanghua XU fei zheng Tongwen WU Xin WANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2016年第2期208-220,共13页
The second-generation Global Ocean Data Assimilation System of the Beijing Climate Center (BCC_GODAS2.0) has been run daily in a pre-operational mode. It spans the period 1990 to the present day. The goal of this pa... The second-generation Global Ocean Data Assimilation System of the Beijing Climate Center (BCC_GODAS2.0) has been run daily in a pre-operational mode. It spans the period 1990 to the present day. The goal of this paper is to introduce the main components and to evaluate BCC_GODAS2.0 for the user community. BCC_GODAS2.0 consists of an observational data preprocess, ocean data quality control system, a three-dimensional variational (3DVAR) data assimilation, and global ocean circulation model [Modular Ocean Model 4 (MOM4)]. MOM4 is driven by six-hourly fluxes from the National Centers for Environmental Prediction. Satellite altimetry data, SST, and in-situ temperature and salinity data are assimilated in real time. The monthly results from the BCC_GODAS2.0 reanalysis are compared and assessed with observations for 1990-201 I. The climatology of the mixed layer depth of BCC_GODAS2.0 is generally in agreement with that of World Ocean Atlas 2001. The modeled sea level variations in the tropical Pacific are consistent with observations from satellite altimetry on interannual to decadal time scales. Performances in predicting variations in the SST using BCC_GODAS2.0 are evaluated. The standard deviation of the SST in BCC_GODAS2.0 agrees well with observations in the tropical Pacific. BCC_GODAS2.0 is able to capture the main features of E1 Nifio Modoki I and Modoki II, which have different impacts on rainfall in southern China. In addition, the relationships between the Indian Ocean and the two types of E1 Nino Modoki are also reproduced. 展开更多
关键词 operational oceanography global ocean 3DVAR E1 Nifio interannual variability
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Cerium and carbon-sulfur codoped mesoporous TiO_(2)nanocomposites for boosting visible light photocatalytic activity 被引量:4
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作者 fei zheng Faqin Dong +7 位作者 Lin Zhou Jieyu Yu Xijie Luo Xingyu Zhang Zhenzhen Lv Luman Jiang Yuheng Chen Mengqing Liu 《Journal of Rare Earths》 SCIE EI CAS CSCD 2023年第4期539-549,共11页
Ce and C-S codoped mesoporous TiO_(2)nanocomposites were synthesized via a sol-gel method integrated with an evaporation-induced self-assembly approach.The basic physicochemical characteristics of the synthetic sample... Ce and C-S codoped mesoporous TiO_(2)nanocomposites were synthesized via a sol-gel method integrated with an evaporation-induced self-assembly approach.The basic physicochemical characteristics of the synthetic samples were analyzed via a series of characterization techniques.The results reveal that C-S and Ce codoping on mesoporous TiO_(2)enhances the photocatalytic activity owing to the synergistic effect caused by narrowing the band gap,enhancing adsorption,trapping and transferring the excited e^(-)/h^(+)pairs and suppressing the recombination of e^(-)/h^(+)pairs.Furthermore,the obtained C,S-TiO_(2)/CeO_(2)materials exhibit large specific surface areas and numerous pores which not only effectively improve the adsorption-enrichment capability,but also supply multi-dimensional mass and electron transfer channels.The photodegradation efficiency of RhB by C,S-TiO_(2)/CeO_(2)within 40 min is nearly 100%,and its degradation efficiency is 6.63 times that of undoped TiO_(2).Recycling experiments show that mesoporous C,S-TiO_(2)/CeO_(2)shows excellent recoverability and stability.Furthermore,by trapping experiments,·O_(2)e^(-)/h^(+)and·OH are the predominant active species and a possible reaction mechanism is proposed. 展开更多
关键词 Photocatalysis Mesoporous TiO_(2) C-S codoping Ce doping Water remediation Rare earths
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