In general,a mesoscale cyclonic(anticyclonic)eddy has a colder(warmer)core,and it is considered as a cold(warm)eddy.However,recently research found that there are a number of"abnormal"mesoscale cyclonic(anti...In general,a mesoscale cyclonic(anticyclonic)eddy has a colder(warmer)core,and it is considered as a cold(warm)eddy.However,recently research found that there are a number of"abnormal"mesoscale cyclonic(anticyclonic)eddies associated with warm(cold)cores in the South China Sea(SCS).These"abnormal"eddies pose a challenge to previous works on eddy detection,characteristic analysis,eddy-induced heat and salt transports,and even on mesoscale eddy dynamics.Based on a 9-year(2000–2008)numerical modelling data,the cyclonic warm-core eddies(CWEs)and anticyclonic cold-core eddies(ACEs)in the SCS are analyzed.This study found that the highest incidence area of the"abnormal"eddies is the northwest of Luzon Strait.In terms of the eddy snapshot counting method,8620 CWEs and 9879 ACEs are detected,accounting for 14.6%and 15.8%of the total eddy number,respectively.The size of the"abnormal"eddies is usually smaller than that of the"normal"eddies,with the radius only around 50 km.In the generation time aspect,they usually appear within the 0.1–0.3 interval in the normalized eddy lifespan.The survival time of CWEs(ACEs)occupies 16.3%(17.1%)of the total eddy lifespan.Based on two case studies,the intrusion of Kuroshio warm water is considered as a key mechanism for the generation of these"abnormal"eddies near the northeastern SCS.展开更多
The linear regression and horizontally stepwise correction are conducted on the observational data from AMSU-A L1 B of NOAA polar orbit satellite to invert a 40-layers(from 1,000 h Pa to 0.1 h Pa) dataset of atmospher...The linear regression and horizontally stepwise correction are conducted on the observational data from AMSU-A L1 B of NOAA polar orbit satellite to invert a 40-layers(from 1,000 h Pa to 0.1 h Pa) dataset of atmospheric temperature with a horizontal resolution of 0.5°×0.5° after the correction of satellite antenna pattern and limb adjustment. Case study shows that the inversion data of temperature can reveal the detail structure of warm core in tropical cyclone. We choose two categories of tropical depressions(TDs) over the South China Sea, including the non-developing TDs and developing TDs. Both of them are developed downward from the middle and upper level to the lower level. Comparison between the evolutions of warm core in the two categories of TDs indicates that the warm core is developed downward from the middle and upper troposphere to the sea surface in all the downward-developing TDs. The difference is that in the group of further developing TDs, the warm core in the upper troposphere is intensified suddenly when it is extending to the sea surface. The warm core in the upper and lower troposphere is strengthened in a meantime. But the similar feature is not observed in the non-developing TDs. Then it may be helpful to judge the TD development by monitoring the change in its warm-core structure.展开更多
目的系统评价身上型和身下全身型充气式保温毯维持腹部手术患者围手术期核心体温的有效性,为腹部手术患者选择合适、有效的主动保温方法提供临床依据。方法通过计算机检索PubMed、Cochrane Library、Web of Science、Scopus、Embase、CI...目的系统评价身上型和身下全身型充气式保温毯维持腹部手术患者围手术期核心体温的有效性,为腹部手术患者选择合适、有效的主动保温方法提供临床依据。方法通过计算机检索PubMed、Cochrane Library、Web of Science、Scopus、Embase、CINAHL、中国知网以及万方数据库,收集身上型和身下全身型充气式保温毯对维持腹部手术患者核心体温有效性的随机对照试验,并追溯其参考文献,检索时限均为建库至2023年3月。2位研究者独立进行文献筛选、数据提取和质量评价后,采用Rev Man 5.4软件对纳入文献进行Meta分析。结果最终纳入5项随机对照试验,总样本量为373例患者。Meta分析结果显示,身下全身型充气式保温毯能升高患者术中核心体温[95%CI为0.13(0.02~0.29),P<0.001],降低围术期非计划低体温的发生率[95%CI为0.15(0.03~0.79),P=0.020],并减少术后寒战的发生[95%CI为0.17(0.05~0.63),P=0.008]。结论身下全身型充气式保温毯对维持腹部手术患者围手术期核心体温有效,可降低围术期非计划低体温和寒战的发生风险。展开更多
利用常规观测资料、FY-2C卫星云图、NCEP/NCAR再分析资料,对一次西南低涡暴雨过程进行了诊断分析。结果表明,这次暴雨天气过程的主要影响系统有对流层高层南亚高压、中层低涡、低层切变线(低涡)以及台风"天鹅"。该过程是由3...利用常规观测资料、FY-2C卫星云图、NCEP/NCAR再分析资料,对一次西南低涡暴雨过程进行了诊断分析。结果表明,这次暴雨天气过程的主要影响系统有对流层高层南亚高压、中层低涡、低层切变线(低涡)以及台风"天鹅"。该过程是由3个接连发生的中尺度对流云团直接造成的,发生在西南低涡闭合涡旋范围内的非对称处。利用WRF_ARW(The Advanced Research WRF)中尺度模式进行了数值模拟,结果表明,对流层高层南亚高压脊线附近的强辐散、对流层中层低涡的垂直涡度耦合和对流层低层强劲的东风干冷急流与南风暖湿急流在四川盆地内交汇,促使西南低涡发展、加强。对流层高层的强辐散和低层强辐合相配合,有利于西南低涡的增强、发展。温度场上,发展的西南低涡在300hPa附近出现"暖心"结构,在850hPa以下北冷南暖,冷暖空气交界随着高度的增加向北倾斜。低涡中心南北两侧的次级环流圈上升支在低涡中心附近汇合,出现剧烈的上升运动,促使西南低涡增强。随着高层南亚高压的南移、高空急流的南压,高层辐散减弱,西南低涡也减弱。当中层西风大槽主体移过河套地区,其携带的强冷空气沿高原东侧迅速南下,大量冷空气进入四川盆地,促使西南低涡向南移出盆地,最终减弱、填塞。展开更多
基金The National Natural Science Foundation of China under contract Nos 41906008,41806039,41806030,42076021,41676010 and 41706205the State Key Laboratory of Tropical Oceanography,South China Sea Institute of Oceanology,Chinese Academy of Sciences under contract Nos LTO1902 and LTO1807+9 种基金the Strategic Priority Research Program of Chinese Academy of Sciences under contract No.XDB42000000the Youth Innovation Promotion Association CAS under contract No.2017397the Pearl River S&T Nova Program of Guangzhou under contract No.201806010105the Open Fund of State Key Laboratory of Satellite Ocean Environment Dynamics,Second Institute of OceanographyMNR under contract No.QNHX2022the Startup Foundation for Introducing Talent of Nanjing University of Information Science&Technology under contract No.2019r049the Startup Foundation for Introducing Talent of Zhejiang Ocean Universitythe National Key Research Programs of China under contract Nos2016YFC1401407 and 2017YFA0604100the National Programme on Global Change and Air-Sea Interaction under contract Nos GASIIPOVAI-03 and GASI-IPOVAI-05the Innovation Group Project of Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)under contract No.311020004。
文摘In general,a mesoscale cyclonic(anticyclonic)eddy has a colder(warmer)core,and it is considered as a cold(warm)eddy.However,recently research found that there are a number of"abnormal"mesoscale cyclonic(anticyclonic)eddies associated with warm(cold)cores in the South China Sea(SCS).These"abnormal"eddies pose a challenge to previous works on eddy detection,characteristic analysis,eddy-induced heat and salt transports,and even on mesoscale eddy dynamics.Based on a 9-year(2000–2008)numerical modelling data,the cyclonic warm-core eddies(CWEs)and anticyclonic cold-core eddies(ACEs)in the SCS are analyzed.This study found that the highest incidence area of the"abnormal"eddies is the northwest of Luzon Strait.In terms of the eddy snapshot counting method,8620 CWEs and 9879 ACEs are detected,accounting for 14.6%and 15.8%of the total eddy number,respectively.The size of the"abnormal"eddies is usually smaller than that of the"normal"eddies,with the radius only around 50 km.In the generation time aspect,they usually appear within the 0.1–0.3 interval in the normalized eddy lifespan.The survival time of CWEs(ACEs)occupies 16.3%(17.1%)of the total eddy lifespan.Based on two case studies,the intrusion of Kuroshio warm water is considered as a key mechanism for the generation of these"abnormal"eddies near the northeastern SCS.
基金National Natural Science Foundation of China(40875026,91015011)Project for Natural Science Foundation Teams of Guangdong Province(8351030101000002)Specialized Program for Social Welfare Industries(Meteorological Sector)(GYHY201106036)
文摘The linear regression and horizontally stepwise correction are conducted on the observational data from AMSU-A L1 B of NOAA polar orbit satellite to invert a 40-layers(from 1,000 h Pa to 0.1 h Pa) dataset of atmospheric temperature with a horizontal resolution of 0.5°×0.5° after the correction of satellite antenna pattern and limb adjustment. Case study shows that the inversion data of temperature can reveal the detail structure of warm core in tropical cyclone. We choose two categories of tropical depressions(TDs) over the South China Sea, including the non-developing TDs and developing TDs. Both of them are developed downward from the middle and upper level to the lower level. Comparison between the evolutions of warm core in the two categories of TDs indicates that the warm core is developed downward from the middle and upper troposphere to the sea surface in all the downward-developing TDs. The difference is that in the group of further developing TDs, the warm core in the upper troposphere is intensified suddenly when it is extending to the sea surface. The warm core in the upper and lower troposphere is strengthened in a meantime. But the similar feature is not observed in the non-developing TDs. Then it may be helpful to judge the TD development by monitoring the change in its warm-core structure.
文摘目的系统评价身上型和身下全身型充气式保温毯维持腹部手术患者围手术期核心体温的有效性,为腹部手术患者选择合适、有效的主动保温方法提供临床依据。方法通过计算机检索PubMed、Cochrane Library、Web of Science、Scopus、Embase、CINAHL、中国知网以及万方数据库,收集身上型和身下全身型充气式保温毯对维持腹部手术患者核心体温有效性的随机对照试验,并追溯其参考文献,检索时限均为建库至2023年3月。2位研究者独立进行文献筛选、数据提取和质量评价后,采用Rev Man 5.4软件对纳入文献进行Meta分析。结果最终纳入5项随机对照试验,总样本量为373例患者。Meta分析结果显示,身下全身型充气式保温毯能升高患者术中核心体温[95%CI为0.13(0.02~0.29),P<0.001],降低围术期非计划低体温的发生率[95%CI为0.15(0.03~0.79),P=0.020],并减少术后寒战的发生[95%CI为0.17(0.05~0.63),P=0.008]。结论身下全身型充气式保温毯对维持腹部手术患者围手术期核心体温有效,可降低围术期非计划低体温和寒战的发生风险。
文摘利用常规观测资料、FY-2C卫星云图、NCEP/NCAR再分析资料,对一次西南低涡暴雨过程进行了诊断分析。结果表明,这次暴雨天气过程的主要影响系统有对流层高层南亚高压、中层低涡、低层切变线(低涡)以及台风"天鹅"。该过程是由3个接连发生的中尺度对流云团直接造成的,发生在西南低涡闭合涡旋范围内的非对称处。利用WRF_ARW(The Advanced Research WRF)中尺度模式进行了数值模拟,结果表明,对流层高层南亚高压脊线附近的强辐散、对流层中层低涡的垂直涡度耦合和对流层低层强劲的东风干冷急流与南风暖湿急流在四川盆地内交汇,促使西南低涡发展、加强。对流层高层的强辐散和低层强辐合相配合,有利于西南低涡的增强、发展。温度场上,发展的西南低涡在300hPa附近出现"暖心"结构,在850hPa以下北冷南暖,冷暖空气交界随着高度的增加向北倾斜。低涡中心南北两侧的次级环流圈上升支在低涡中心附近汇合,出现剧烈的上升运动,促使西南低涡增强。随着高层南亚高压的南移、高空急流的南压,高层辐散减弱,西南低涡也减弱。当中层西风大槽主体移过河套地区,其携带的强冷空气沿高原东侧迅速南下,大量冷空气进入四川盆地,促使西南低涡向南移出盆地,最终减弱、填塞。
