The Tibetan Plateau Surface–Atmosphere Coupling System and Its Weather and Climate Effects: The Third Tibetan Plateau Atmospheric Science Experiment

The Tibetan Plateau(TP) is a key area affecting forecasts of weather and climate in China and occurrences of extreme weather and climate events over the world. The China Meteorological Administration, the National Natural Science Foundation of China, and the Chinese Academy of Sciences jointly initiated the Third Tibetan Plateau Atmospheric Science Experiment(TIPEX-Ⅲ) in 2013, with an 8–10-yr implementation plan. Since its preliminary field measurements conducted in 2013, routine automatic sounding systems have been deployed at Shiquanhe, Gaize, and Shenzha stations in western TP, where no routine sounding observations were available previously. The observational networks for soil temperature and soil moisture in the central and western TP have also been established. Meanwhile, the plateau-scale and regional-scale boundary layer observations, cloud–precipitation microphysical observations with multiple radars and aircraft campaigns, and tropospheric–stratospheric air composition observations at multiple sites, were performed. The results so far show that the turbulent heat exchange coefficient and sensible heat flux are remarkably lower than the earlier estimations at grassland, meadow, and bare soil surfaces of the central and western TP. Climatologically, cumulus clouds over the main body of the TP might develop locally instead of originating from the cumulus clouds that propagate northward from South Asia. The TIPEX-Ⅲ observations up to now also reveal diurnal variations, macro-and microphysical characteristics, and water-phase transition mechanisms, of cumulus clouds at Naqu station. Moreover, TIPEX-Ⅲ related studies have proposed a maintenance mechanism responsible for the Asian "atmospheric water tower" and demonstrated the effects of the TP heating anomalies on African, Asian, and North American climates. Additionally, numerical modeling studies show that the Γ distribution of raindrop size is more suitable for depicting the TP raindrop characteristics compared to the M–P distribution, the overestimation of sensible heat flux can be reduced via modifying the heat transfer parameterization over the TP, and considering climatic signals in some key areas of the TP can improve the skill for rainfall forecast in the central and eastern parts of China. Furthermore, the TIPEX-Ⅲ has been promoting the technology in processing surface observations, soundings, and radar observations, improving the quality of satellite retrieved soil moisture and atmospheric water vapor content products as well as high-resolution gauge–radar–satellite merged rainfall products, and facilitating the meteorological monitoring, forecasting, and data sharing operations.     

鄂尔多斯活动地块边界带地震动力学模型与强震危险性研究项目及进展

研究银川盆地的构造活动特征对于认识青藏、鄂尔多斯和阿拉善3大地块的相互作用具有重要意义。银川盆地东南缘的面子山—猪头岭一带地形高差显著,影像上线性明显,可能发育一条未知的活动断裂。本文沿面子山—清水营一线开展了野外地质调查、探槽开挖和地层年代测试等工作,结果表明：银川盆地东南缘发育面子山—清水营断裂,全长50 km,以猪头岭北为界,分为面子山断层和清水营断层两段。面子山断层以高角度正断为主,断层擦痕显示具有左旋走滑运动,走向北东,跨断层数条冲沟显示具有左旋扭动特征;而清水营断层则表现为逆断层,走向北东东,发育陡坎地貌。该断裂断错了（23.65 ± 1.17） ka BP和（33.16 ± 1.82） ka BP的沉积地层,表明断裂最新活动时代为晚更新世晚期。该断层的发现表明,鄂尔多斯地块的西北边界复杂,构造变形带较宽,且不严格的受控于断陷盆地的边界断裂,其构造变形已扩张到地块一侧,这可能与青藏高原持续向东北向的推挤扩展有关。

     

Recent Progress in Dual-Polarization Radar Research and Applications in China

Dual-polarization(dual-pol)radar can measure additional parameters that provide more microphysical information of precipitation systems than those provided by conventional Doppler radar.The dual-pol parameters have been successfully utilized to investigate precipitation microphysics and improve radar quantitative precipitation estimation(QPE).The recent progress in dual-pol radar research and applications in China is summarized in four aspects.Firstly,the characteristics of several representative dual-pol radars are reviewed.Various approaches have been developed for radar data quality control,including calibration,attenuation correction,calculation of specific differential phase shift,and identification and removal of non-meteorological echoes.Using dual-pol radar measurements,the microphysical characteristics derived from raindrop size distribution retrieval,hydrometeor classification,and QPE is better understood in China.The limited number of studies in China that have sought to use dual-pol radar data to validate the microphysical parameterization and initialization of numerical models and assimilate dual-pol data into numerical models are summarized.The challenges of applying dual-pol data in numerical models and emerging technologies that may make significant impacts on the field of radar meteorology are discussed.     

新丰江水库区和平地电站电阻率深孔多电极抗干扰观测实验

随着社会经济的快速发展,传统的地震地电阻率观测想避免环境干扰的影响已经是不可能的事情。在这种形势下,由横向向纵深发展的深埋电极电阻率观测方法正得到越来越多的重视和研究。通过利用和平地电站已开展近20年的深孔电阻率观测试验的有利条件,进行深孔多电极组合实验观测研究。总结了多种实验结果,证明在深孔中设置多电极组合的优势,并表明电极只要埋人地下一定深度后,就能达到压抑地表的干扰影响。     

云南腾冲火山旅游景观探讨

腾冲火山活动始于上新世,形成橄榄玄武岩、安山玄武岩、安山 岩及英安岩4大类,分为两个喷发旋回,4个喷发期。主要景观由全新世的第四期火山机构组成,景观分为火山锥、熔岩被、火山地热、火山与热水观赏石等。岩石属高钾钙碱性火山岩系,是挤压造山带的产物。腾冲火山群深部存在熔融岩浆囊,是休眠火山,但岩浆囊内绝大部分岩浆已喷发。结合人文景观,腾冲火山群是不可多得的科学考察和旅游景区。     

小肠袢聚集对预测腹膜假黏液瘤患者小肠系膜挛缩的CT价值研究

目的：探讨CT扫描图像联合多平面重建（MPR）及容积重建（VR）技术在评判小肠袢聚集对预测腹膜假黏液瘤（PMP）患者小肠系膜挛缩中的临床应用价值。方法：回顾性分析2018年1月至2019年12月我院黏液瘤科179例经手术病理证实为腹膜假黏液瘤的患者,其中31例术中证实存在小肠系膜挛缩,148例无小肠系膜挛缩,通过CT轴位、多平面重建、容积重建技术分别进行小肠袢聚集的判定,并进一步预测小肠系膜挛缩的诊断效能,采用单因素logistic回归、ROC曲线及spearman秩相关性分析,P<0.05为有显著统计学差异。结果：采用单因素logistic回归方法分析小肠袢聚集的检出率：VR>冠状位>轴位>矢状位,对系膜挛缩诊断效能的预测：VR>冠状位>轴位>矢状位。采用ROC曲线分析小肠袢聚集对预测小肠系膜挛缩的诊断效能：轴位敏感性58.8%、特异度79.6%、阳性预测值46.5%、阴性预测值86.5%;冠状位敏感性55.9%、特异度89.6%、阳性预测值61.4%、阴性预测值87.1%;矢状位敏感性50.0%、特异度72.6%、阳性预测值35.4%、阴性预测值82.8%;VR敏感性76.5%、特异度78.8%、阳性预测值52%、阴性预测值91.8%。spearman秩相关性分析：通过轴位、冠状位、矢状位、VR对小肠袢聚集的判定与预测小肠系膜挛缩的结果有较高相关性。结论：单一轴位CT图像对于小肠袢聚集的评价效能有限,结合冠状位和VR,有助于提高小肠袢聚集评价的准确性;小肠袢聚集对于预测小肠系膜挛缩的结果有较高相关性;单纯利用小肠袢聚集判定小肠系膜挛缩,敏感度及特异度有限,需要进一步结合其他研究提高术前小肠系膜挛缩的检出率。     

X波段双线偏振雷达不同衰减订正方法对比及其对降水估测影响研究

本文分析了X波段双线偏振雷达衰减订正各种方法的特点,考虑到差传播相移率 作为衰减订正的一种有效途径,以及由于 值较小,数据质量不稳定,往往导致订正误差较大,因此提出了同时利用水平反射率因子 与差传播相移率 进行衰减订正的 综合法。基于同样的考虑,在随后利用 、 进行降水估测时,提出了 综合估测方法。利用中国科学院寒区旱区环境与工程研究所和成都锦江电子系统工程有限公司,在研制3.2cm波长同时收发式多普勒偏振天气雷达过程中,2005年8月在平凉外场试验取得了一批观测资料,对提出的衰减订正综合法及降水估测综合法的效果进行了分析检验,结果表明, 综合法对 、 有稳定的订正效果,并且订正速度快,能够达到实时运行的要求。2005年8月11日从15:08:03--22:05:46,间隔5-12分钟不等,雷达开机取得了连续的观测资料,通过对这次降水过程的对比分析表明, 综合估测法比单因子 法、 关系法,适用估测的降水强度变化范围广,与自动雨量记的观测结果较为吻合。 关系法中,利用订正后的 值,比利用订正前的 值,降水估测值与雨量记实测值的误差明显减小,说明衰减订正后的雷达数据质量有明显的改善。     

青藏高原零度层亮带的识别订正方法及在雷达估测降水中的应用

零度层亮带是指雪花或冰晶降落到零度层附近,表面发生融化而使雷达反射率突然增大的现象.它是影响雷达资料质量的重要因素,常会导致雷达估测降水的高估.青藏高原海拔高、零度层低,零度层以下的降水范围非常有限,亮带对青藏高原地区的雷达估测降水的影响更加显著.因此,对亮带进行自动识别订正,对提高青藏高原雷达降水估测的精度有重要意义.本文在考虑青藏高原遮挡严重的情况下,通过计算反射率垂直廓线来识别零度层亮带,对亮带区域进行订正,并将亮带订正前后的混合扫描反射率分别估测降水,分析亮带订正对降水估测误差的影响.结果表明:雷达识别的亮带高度在探空资料零度层以下几百米内;亮带订正前,反射率垂直廓线在零度层附近有显著弯曲,雷达对降水的估测明显偏高;亮带订正后,反射率垂直廓线在零度层附近的显著弯曲消失,雷达估测的降水量与雨量计的观测值较一致,降水估测误差比订正前明显减小.     

中元古界昆阳群因民组铁铜矿的成矿地球化学研究

因民组是川滇地区重要的铁铜矿赋存层位之一。系统地研究了因民组铁铜矿床的常量元素、微量元素、稀土元素、同位素和包裹体的特征，阐明成矿作用具有火山热水喷流－沉积成矿作用的地球化学特点。     

CT腹膜癌指数对腹膜假黏液瘤可切除性价值研究

目的：探讨CT腹膜癌指数（CT-PCI）对腹膜假黏液瘤（PMP）可切除性的价值研究。方法：回顾性分析2019年1月至2020年4月航天中心医院黏液瘤科57例经手术病理证实为PMP患者的术前及术后CT图像,进行CT-PCI评分,并对术前及术后的CT-PCI评分进行统计学分析,通过CT-PCI评估手术可切除性。结果：术前CT-PCI分数较高的区域集中在0~8区,以0区为著,9~12区评分较低;术后变化最显著的区域为0区,其次是7、6和8区,9区变化最小。结论：CT-PCI可在术前明确PMP患者腹腔内肿瘤的分布及大小情况,为临床医生在术前对减瘤手术的范围提供影像学支持,可为PMP患者的减瘤程度提供初步预判,也可为PMP其他相关科学研究提供重要依据。