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Comparison of the Minimum Bounding Rectangle and Minimum Circumscribed Ellipse of Rain Cells from TRMM

Advances in Atmospheric Sciences 2024年第3期41卷 391-406页

作者： hongke cai Yaqin MAO Xuanhao ZHU Yunfei FU Renjun ZHOU Plateau Atmospheric and Environment Laboratory of Sichuan Province School of Atmospheric SciencesChengdu University of Information TechnologyChengdu 610225China School of Earth and Space Sciences University of Science and Technology of ChinaHefei 230026China Center for Atmospheric Optics Anhui Institute of Optics and Fine MechanicsChinese Academy of SciencesHefei 230031China

Based on the TRMM dataset, this paper compares the applicability of the improved MCE(minimum circumscribed ellipse), MBR(minimum bounding rectangle), and DIA(direct indexing area) methods for rain cell fitting. These three methods can reflect the geometric characteristics of clouds and apply geometric parameters to estimate the real dimensions of rain cells. The MCE method shows a major advantage in identifying the circumference of rain cells. The circumference of rain cells identified by MCE in most samples is smaller than that identified by DIA and MBR, and more similar to the observed rain cells. The area of rain cells identified by MBR is relatively robust. For rain cells composed of many pixels(N> 20), the overall performance is better than that of MCE, but the contribution of MBR to the best identification results,which have the shortest circumference and the smallest area, is less than that of MCE. The DIA method is best suited to small rain cells with a circumference of less than 100 km and an area of less than 120 km^(2), but the overall performance is mediocre. The MCE method tends to achieve the highest success at any angle, whereas there are fewer “best identification”results from DIA or MBR and more of the worst ones in the along-track direction and cross-track direction. Through this comprehensive comparison, we conclude that MCE can obtain the best fitting results with the shortest circumference and the smallest area on behalf of the high filling effect for all sizes of rain cells.

关键词： TRMM minimum bounding rectangle minimum circumscribed ellipse

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Main Detrainment Height of Deep Convection Systems over the Tibetan Plateau and Its Southern Slope

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Advances in Atmospheric Sciences 2019年第10期36卷 1078-1088页

作者： Quanliang CHEN Guolu GAO Yang LI hongke cai Xin ZHOU Zhenglin WANG School of Atmospheric Sciences Chengdu University of Information Technology and Plateau Atmosphere and Environment Key Laboratory of Sichuan Province

Deep convection systems (DCSs) can rapidly lift water vapor and other pollutants from the lower troposphere to the upper troposphere and lower stratosphere. The main detrainment height determines the level to which the air parcel is lifted. We analyzed the main detrainment height over the Tibetan Plateau and its southern slope based on the CloudSat Cloud Profiling Radar 2B_GEOPROF dataset and the Aura Microwave Limb Sounder Level 2 cloud ice product onboard the Atrain constellation of Earth-observing satellites. It was found that the DCSs over the Tibetan Plateau and its southern slope have a higher main detrainment height (about 10-16 km) than other regions in the same latitude. The mean main detrainment heights are 12.9 and 13.3 km over the Tibetan Plateau and its southern slope, respectively. The cloud ice water path decreases by 16.8% after excluding the influences of DCSs, and the height with the maximum increase in cloud ice water content is located at 178 hPa (about 13 km). The main detrainment height and outflow horizontal range are higher and larger over the central and eastern Tibetan Plateau, the west of the southern slope, and the southeastern edge of the Tibetan Plateau than that over the northwestern Tibetan Plateau. The main detrainment height and outflow horizontal range are lower and broader at nighttime than during daytime.

关键词： main detrainment height deep convection systems Tibetan Plateau and its southern slope A-train

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Optical Properties of Cirrus Transition Zones over China Detected by CALIOP

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Journal of Meteorological Research 2017年第3期31卷 576-585页

作者： hongke cai Yunfei FU Quanliang CHEN Xiao FENG Xin TIE Ranting TAO Kepiao XU School of Atmospheric Science Chengdu University of Information Technology/Plateau Atmospheric and Environment Laboratory of Sichuan Province School of Earth and Space Sciences University of Science and Technology of China

A transition zone near cirrus lateral boundaries can be detected by CALIOP （cloud-aerosol lidar with orthogonal polarization）. In the present study, for such transition zones over China, a number of optical properties, such as the backscatter coefficient and depolarization ratio, showed transitional characteristics between cirrus and clear sky. The stepped horizontal profile showed sharp changes in particle number and morphology between cirrus clouds and clear sky. The color ratio, however, was unable to show cirrus transition features because of the low signal-to-noise ratio. Typical ice particles presented a color ratio of 0.55-1.25 and a depolarization ratio of greater than 0.12, which were significantly higher than those of clear sky. Therefore, optical properties in transition took the form of stepwise hori- zontal profiles. The proportion of typical-featured particles also demonstrated a stepped horizontal profile similar to the optical characteristics, but the relationship between the proportion and the optical characteristics was not uniform in the cirrus clouds, transition zone, and clear sky. Therefore, the optical changes in the transition zone were caused by not only the change in particle concentration, but also the change in the particles themselves. The probability dens- ity distribution of the transition-zone widths showed a positive skewness distribution, and transition zones with widths of 3-5 km occurred most frequently. Overall, transition-zone width decreased with increasing temperature and increased with increasing vertical and horizontal wind speeds. This trend demonstrated independence with the direc- tion of the vertical and horizontal winds. These observations implied that the transitional features were caused by ma- terial exchange, such as entrainment and turbulent transport, near the cirrus lateral boundaries, and by the phase trans- formation of particles, such as sublimation.

关键词： cirrus transition zone lidar temperature wind speed

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The tropical Pacific cold tongue mode and its associated main ocean dynamical process in CMIP5 models

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Earth and Planetary Physics 2019年第5期3卷 400-413页

作者： Yang Li QuanLiang Chen JianPing Li WenJun Zhang MinHong Song Wei Hua hongke cai XiaoFei Wu College of Atmospheric Science Plateau Atmosphere and Environment Key Laboratory of Sichuan ProvinceChengdu University of Information TechnologyChengdu 610225China Key Laboratory of Physical Oceanography-Institute for Advanced Ocean Studies Ocean University of China and Qingdao National Laboratory for Marine Science and TechnologyQingdao 266100China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Key Laboratory of Meteorological Disaster of Ministry of EducationNanjing University of Information Science and TechnologyNanjing 210044China

The cold tongue mode(CTM),which represents the out-of-phase relationship in sea surface temperature anomaly(SSTA)variability between the Pacific cold tongue region and elsewhere in the tropical Pacific,shows a long-term cooling trend in the eastern equatorial *** this study,we investigate how well the CTM is reproduced in historical simulations generated by the 20 models considered in Phase 5 of the Coupled Model Intercomparison Project(CMIP5).Qualitatively,all 20 models roughly capture the cooling SSTA associated with the ***,a quantitative assessment(i.e.,Taylor diagrams and the ratio of the trend between the simulations and observations)shows that only five of these 20 models(i.e.,CESM1-CAM5,CMCC-CM,FGOALS-g2,IPSL-CM5B-LR,and NorESM1-M)can reproduce with useful accuracy the spatial pattern and long-term trend of the *** find that these five models generally simulate the main ocean dynamical process associated with the *** is,these models adequately capture the long-term cooling trend in the vertical advection of the anomalous temperature by the mean *** conclude that the performance of these CMIP5 models,with respect to simulations of the long-term cooling trend associated with the vertical advection,and the related long-term decreasing trend of the vertical gradient of the oceanic temperature anomaly,can play an important role in successful reproduction of the CTM.

关键词： tropical Pacific La Nina-like cold tongue mode ocean dynamical process CMIP5

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The first two leading modes of the tropical Pacific and their linkage without global warming

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Earth and Planetary Physics 2019年第2期3卷 157-165页

作者： Yang Li QuanLiang Chen XiaoRan Liu Nan Xing ZhiGang Cheng hongke cai Xin Zhou Dong Chen XiaoFei Wu MingGang Li College of Atmospheric Science Plateau Atmosphere and Environment Key Laboratory of Sichuan ProvinceChengdu University of Information Technology State Chongqing Climate Center Beijing Meteorological Service

A discrepancy remains in the first two leading empirical orthogonal function(EOF) modes of the tropical Pacific sea surface temperature anomaly(SSTA) based on observations since the 1980s. The EOF1 mode, representing the El Ni?o-Southern Oscillation(ENSO), is a robust result. However, the EOF2 features either El Ni?o Modoki(EM) or ENSO evolution during different periods, which is probably associated with the impacts of global warming. The underlying question is what the EOF2 mode of the tropical Pacific would be without global warming. Using the CMIP5 preindustrial scenario to exclude the influence of global warming, we find that the EOF1 mode of the tropical Pacific SSTA represents ENSO and that the EOF2 mode is not EM. According to the lead–lag correlation between the ENSO and EOF2 modes, the linkage between these two modes is as follows: …El Ni?o → EOF2 → La Ni?a →–EOF2 → El Ni?o…. By analyzing the evolution of sea surface temperature, surface wind, and subsurface ocean temperature anomalies, we find the mechanism linking the ENSO and EOF2 modes is the air–sea interaction associated with the ENSO cycle. This result suggests that the EOF2 mode represents an aspect of ENSO evolution under preindustrial conditions. Therefore, this study further indicates that the EM is probably due to the influence of global warming.

关键词： El Nino-Southern Oscillation(ENSO) ENSO evolution global warming air-sea interaction

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卫星遥感监测2003~2018年中国甲烷时空特征分析

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遥感技术与应用 2024年第4期39卷 841-849页

作者：彭禹奇蔡宏珂蔡兆男成都信息工程大学大气科学学院四川成都610225 中国科学院大气物理研究所碳中和研究中心北京100029

为了更加充分地了解中国地区甲烷浓度的分布情况,利用C3S提供的甲烷浓度资料分析2003~2018年中国地区甲烷浓度的时空分布特征。结果表明:①甲烷浓度呈现东南高西北低的分布情况,甲烷浓度高值区主要分布在湖南、湖北、广西等地,低值区位... 详细信息

为了更加充分地了解中国地区甲烷浓度的分布情况,利用C3S提供的甲烷浓度资料分析2003~2018年中国地区甲烷浓度的时空分布特征。结果表明:①甲烷浓度呈现东南高西北低的分布情况,甲烷浓度高值区主要分布在湖南、湖北、广西等地,低值区位于青海和西藏等地。我国甲烷浓度年际变化随时间呈增长趋势,2003~2006年甲烷浓度保持相对稳定,2007~2018年甲烷浓度出现明显的上升。②甲烷浓度具有明显的季节变化特征,夏秋季高于春冬季,其中秋季浓度最高为1781 ppbv,春季浓度最低为1748 ppbv。甲烷浓度的高峰值出现在8、9月份,低峰值出现在3、4月份。③为了更好地分析中国地区甲烷浓度,将我国分为六大地理区域,分别是东北地区、中南地区、华东地区、华北地区、西北地区、西南地区。其中,华东地区和中南地区的甲烷浓度较高,西北地区和西南地区的甲烷浓度较低。

关键词：甲烷时空尺度多年变化中国

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微RNA-194参与结直肠癌细胞上皮-间质转化及迁移和侵袭的作用机制探讨

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肿瘤 2016年第3期36卷 280-287页

作者：蔡洪科陈茜王继见邓甬川重庆医科大学附属第二医院胃肠外科重庆400010 重庆医科大学分子医学与肿瘤研究中心重庆400016 浙江大学医学院附属第二医院肿瘤外科浙江杭州310009

目的 :观察微RNA-194(micro RNA-194,mi R-194)在结直肠癌细胞侵袭和迁移过程中的作用,并探讨其参与细胞上皮-间质转化的作用机制。方法 :将携带mi R-194基因的质粒载体转染结直肠癌SW480细胞,构建稳定高表达mi R-194的细胞系mi R-194-4... 详细信息

目的 :观察微RNA-194(micro RNA-194,mi R-194)在结直肠癌细胞侵袭和迁移过程中的作用,并探讨其参与细胞上皮-间质转化的作用机制。方法 :将携带mi R-194基因的质粒载体转染结直肠癌SW480细胞,构建稳定高表达mi R-194的细胞系mi R-194-480,并观察该细胞的形态学变化。采用MTT法、细胞划痕愈合实验和Transwell迁移及侵袭实验分别观察mi R-194-480细胞的增殖、迁移和侵袭能力;同时,采用实时荧光定量PCR和蛋白质印迹法分别检测mi R-194高表达对上皮-间质转化相关分子表达水平的影响。结果 :高表达mi R-194的结直肠癌mi R-194-480细胞系构建成功,细胞由之前的扁圆形转变为梭形,发生明显的间质性改变。mi R-194质粒转染后,mi R-194-480细胞的增殖能力并未见明显变化(P>0.05),但细胞迁移和侵袭能力却明显增强(P值均<0.001)。mi R-194高表达能够上调基质金属蛋白酶-2(matrix metalloproteinase-2,MMP-2)和波形蛋白(vimentin)的表达水平(P<0.05,P<0.001),而E-钙黏蛋白(E-cadherin)表达明显下调(P<0.01)。结论 :mi R-194通过调节MMP-2、E-cadherin和vimentin的表达,参与结直肠癌细胞的上皮-间质转化,从而明显提高结直肠癌细胞的迁移和侵袭能力。

关键词：结直肠肿瘤微RNAs 肿瘤转移肿瘤浸润 MiR-194 上皮-间质转化

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涟钢1号高炉软水密闭循环冷却系统改造

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炼铁 2005年第2期24卷 25-27页

作者：唐清华李利蓉蔡宏科湖北省武汉市武汉理工大学资源与环境工程学院 430070 武汉理工大学涟源钢铁集团有限公司

涟钢1号高炉大修扩容改造时,在高炉炉体及热风炉冷却系统采用了先进的软水密闭循环冷却系统,回水冷却采用表面蒸发式空冷器。高炉投产后运行效果好,补水量少。

关键词：高炉软水密闭循环热风炉扩容改造炉体大修冷却系统涟钢投产运行效果

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全球变暖背景下热带太平洋海温长期趋势研究

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气候与环境研究 2019年第6期24卷 723-734页

作者：李扬陈权亮蔡宏珂汪正林成都信息工程大学大气科学学院高原大气与环境四川省重点实验室

热带太平洋对全球的气候有重要作用。然而,关于全球变暖背景下热带太平洋海温长期趋势的研究,迄今为止仍有争议。本文利用多套海表温度资料和次表层海温资料,基于无参的趋势估计方法(Theil-Sen趋势),分析了热带太平洋海表温度长期趋势... 详细信息

热带太平洋对全球的气候有重要作用。然而,关于全球变暖背景下热带太平洋海温长期趋势的研究,迄今为止仍有争议。本文利用多套海表温度资料和次表层海温资料,基于无参的趋势估计方法(Theil-Sen趋势),分析了热带太平洋海表温度长期趋势及赤道太平洋次表层海温长期趋势。多套资料的结果均表明在全球变暖背景下,热带太平洋冷舌区为长期冷趋势,而冷舌区之外的热带太平洋区域为长期暖趋势,即似La Nina(La Ninalike)海温长期趋势。此海温长期趋势是由热带太平洋冷舌模态所引起。当冷舌模态为正位相时,对应热带太平洋冷舌区为冷海温异常,而冷舌区之外的热带太平洋为暖海温异常。冷舌模态时间序列主要为长期趋势,而造成冷舌模态长期趋势的机制是全球变暖强迫下的海洋动力反馈过程。赤道太平洋的表层和次表层海温似La Nina型的长期趋势,是冷舌模态在表层海温和次表层海温上的不同体现。

关键词：全球变暖热带太平洋海温长期趋势

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精准医学在肿瘤外科学教学中的探索

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继续医学教育 2019年第3期33卷 18-20页

作者：陈茜蔡洪科重庆医科大学附属第二医院病理科重庆400010 重庆医科大学附属第二医院胃肠外科重庆400010

精准医学是以个体化治疗为基础,结合现代科技手段,基于各种组学研究产生的大数据分析,对不同患者给予针对性治疗的新模式。精准医学的发展对肿瘤的诊疗带来巨大的变化,同时对肿瘤外科学的教学提出更高的要求。目前国内肿瘤外科学教学存... 详细信息

精准医学是以个体化治疗为基础,结合现代科技手段,基于各种组学研究产生的大数据分析,对不同患者给予针对性治疗的新模式。精准医学的发展对肿瘤的诊疗带来巨大的变化,同时对肿瘤外科学的教学提出更高的要求。目前国内肿瘤外科学教学存在诸多问题,精准医学时代要求肿瘤外科学教学应不断探索,临床与科研密切结合,有效利用信息资源,积极开展文献检索课程,将PBL与CBL等教学模式并轨融合,利用互联网线上、线下联合多媒体等教学模式,增加实验室投入,鼓励临床与科研相互转化并开展学术交流,将精准医学理念贯穿于肿瘤外科学基础与临床教学过程中,只有如此才能适应精准医学时代的要求,为我国医疗事业培养创新型医学人才。

关键词：精准医学肿瘤外科学教学实践教学模式转化医学创新医学

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