Impact of land–sea thermal contrast on interdecadal variation in circulation and blocking     

Yongli He  Jianping Huang  Mingxia Ji 《Climate Dynamics》2014,43(12):3267-3279

The impact of asymmetric thermal forcing associated with land–sea distribution on interdecadal variation in large-scale circulation and blocking was investigated using observations and the coupled model intercomparison project outputs. A land–sea index (LSI) was defined to measure asymmetric zonal thermal forcing; the index changed from a negative to a positive anomaly in the 1980s. In the positive phase of the LSI, the 500 hPa geopotential height decreased in the polar regions and increased in the mid-latitudes. The tropospheric planetary wave activity also became weaker and exerted less easterly forcing on the westerly wind. These circulation changes were favorable for westerly wind acceleration and reduced blocking. In the Atlantic, the duration of blocking decreased by 38 % during the positive LSI phase compared with that during the negative phase; in Europe, the number of blocking persisting for longer than 10 days during the positive LSI phase was only half of the number during the negative phase. The observed surface air temperature anomaly followed a distinctive “cold ocean/warm land” (COWL) pattern, which provided an environment that reduced, or destroyed, the resonance forcing of topography and was unfavorable for the development and persistence of blocking. In turn, the responses of the westerly and blocking could further enhance continental warming, which would strengthen the “cold ocean/warm land” pattern. This positive feedback amplified regional warming in the context of overall global warming.  相似文献   

基于ICESat-2 ATLAS数据的DEM高程精度评价     

丁夏萌  张继贤  郭婧  张鹤  常亚茹 《测绘通报》2022,(12):84-90

为探究ASTER GDEMV3、SRTM1 DEM和AW3D30 DEM 3种开源DEM数据的高程精度,本文以高精度ICESat-2 ATLAS测高数据为参考数据,利用GIS统计分析、误差相关分析及数理统计对DEM的高程精度进行对比评价。结果表明：①AW3D30的质量最稳定;SRTM1 DEM在平原精度最高;在高原山地精度由高到低依次为AW3D30 DEM、ASTER GDEMV3、SRTM1 DEM。②DEM数据高程精度受地表覆盖影响较大,且与地形因素密切相关,在相同地表覆盖的两个研究区中DEM数据高程精度表现情况不一致,SRTM在平原地表覆盖下精度表现最好,平均误差为3.15 m,AW3D30 DEM在山地地表覆盖下精度表现最好,平均误差为7.61 m。③坡度对DEM数据的高程精度影响较大,在两个研究区3种DEM数据的高程误差均随坡度的增加而增加;坡向对DEM数据的高程精度影响较小,未发现明显的规律。  相似文献   

基于平面波解构滤波的速度无关动校正及速度分析方法     

陈鑫  王德利  孟阁阁  孙海龙  王通 《世界地质》2014,33(4):895-903

为了避免速度分析拾取速度参数引起的繁复费时、拾取参数不准确导致的校正效果不佳和传统动校正的拉伸畸变问题,利用速度无关动校正方法进行相关处理。通过数据解构获取局部同相轴斜率,解析斜率数据与速度的关系,由局部斜率可直接获得动校正所需时差参数,其信息足以进行动校正处理。通过模拟和实际数据进行的实验计算,证明此方法优于常规动校正处理效果。  相似文献   

自贡大山铺废卤(气)井泄漏原因分析     

吴何  李振华  刘晓博 《四川地质学报》2014,34(3):394-398

四川省自贡市盐卤开发有近2 000年历史,大山铺曾是自贡市井矿盐生产基地之一,由于长期从事岩盐、天然气开采,留下了大量的废卤(气)井。分析表明:大山铺地下地质情况较为复杂,构造断裂、裂隙发育,且连通性较好,给卤(气)上窜提供了地质条件;卤(气)井未封井或套管腐蚀穿孔、破裂造成卤水及伴生天然气沿裂隙上窜,表现为对含水层、土地资源破坏及对空气的污染。  相似文献   

云浮硫铁矿矿山地质环境问题及对策分析     

苏志军  李英华  杜鹏  李竞  贺小黑 《化工矿产地质》2014,36(3):167-172

云浮硫铁矿已开采多年,但开采中带来了一系列环境问题。本文通过对矿区进行的地质环境综合评价,查明了主要矿山地质环境存在的问题,并分析了其原因;利用敏感因子—综合分值评价法,对云浮硫铁矿矿山地质环境质量进行分区,提出了矿山地质环境恢复治理建议,最大程度的降低矿山开采对地质环境的不利影响,努力构建"和谐矿区,和谐社会",促进生态环境、经济和社会的协调可持续发展。  相似文献   

山东省油页岩资源特征及开发利用前景     

薛成  邢楠  赵赫  杨栋栋  曹治国 《山东地质》2014,(6):28-31

随着石油资源可用量的不断减少,页岩气、油页岩、油砂与稠油作为一种新能源,近年来备受人们的重视。山东省存在着丰富的油页岩资源。近年来笔者通过收集前人相关资料、野外地质填图、钻探编录、典型矿区考察、关键样品化验分析等手段对其进行了初步研究,初步认识了山东地区油页岩的资源特征及其形成环境,对未来山东地区油页岩矿的预测及潜力的评价具有一定的指导与借鉴作用。  相似文献   

内蒙古敖兰敖日格一带侵入岩地球化学数据的统计分析与地质解释     

庞雪娇  付俊彧  宋维民  陶楠  卞雄飞  吴桐 《地质与资源》2014,23(2):138-145

采用数理统计方法,研究了内蒙古科右中旗敖兰敖日格一带出露的侵入岩的岩石地球化学特征.选用地质因子分析等统计方法,分析了解体后的敖兰敖日格岩体、杜尔基岩体中各侵入岩填图单位的常量元素、区域主要成矿元素等地球化学数据,总结了侵入岩的岩石地球化学特征由老到新的演化趋势及变化规律,探讨了各主要岩体与区域成矿的相关性,为区域地质找矿提供依据.  相似文献   

陕北煤矿区地质环境保护与恢复治理措施——以神府矿区郭家湾煤矿为例     

李永红  何意平  康金栓  张新宇  李辉  滕宏泉  丁佳 《中国煤炭地质》2014,(4):41-45,57

郭家湾煤矿地处神府矿区新民采区西北部,为生态环境脆弱区。井田七层煤三个煤组开采后引发地面塌陷、含水层疏干、土地结构变化等地质环境问题,严重制约了地方经济的发展。为了煤炭资源可持续发展,研究陕北煤矿区地质环境保护与恢复治理措施,以1∶10000野外详细调查为依据,首先进行现状评估,然后针对矿山工程建设可能遭受、加剧、引发的矿山地质环境问题进行预测评估,最后提出了以移民搬迁、回填裂缝、生态恢复、建立矿山地质环境监测体系等为主的防治措施,让煤矿开采与矿山地质环境问题恢复治理并行。旨为陕北地区乃至全国煤矿,在保护地质环境中开发利用矿产资源提供依据和示范。  相似文献   

降雨入渗补给地下水数值模拟研究     

何渊 《中国煤炭地质》2014,(7):36-41

针对在地下水资源评价中入渗补给量采用经验估算存在较大误差的问题,以神东矿区为例,在广泛调查矿区包气带岩性结构并结合野外取样、室内参数测定的基础上,采用数值模拟的方法建立包气带水分运移数值模拟模型,定量模拟矿区内不同地段降雨入渗强度,探讨影响降雨入渗强度的主要因素,计算得出研究区降雨入渗系数大致在0.18~0.27,分析认为影响降雨入渗强度的因素有降雨量、潜水埋深、包气带岩性等。其中在研究区广泛分布的风积沙对地下水资源起到了一定的保护作用。  相似文献   

Predicting lake water quality responses to load reduction: a three-dimensional modeling approach for total maximum daily load   总被引：2，自引：0，他引：2  

Z. Wang  R. Zou  X. Zhu  B. He  G. Yuan  L. Zhao  Y. Liu 《International Journal of Environmental Science and Technology》2014,11(2):423-436

Water quality restoration efforts often suffer the risk of ineffectiveness and failure due to lack of quantitative decision supports. During the past two decades, the restoration of one of China’s most heavily polluted lakes, Lake Dianchi, has experienced costly decision ineffectiveness with no detectable water quality improvement. The governments are planning to invest tremendous amount of funds in the next 5 years to continue the lake restoration process; however, without a quantitative understanding between the load reduction and the response in lake water quality, it is highly possible that these planned efforts would suffer the similar ineffectiveness as before. To provide scientifically sound decision support for guiding future load reduction efforts in Lake Dianchi Watershed, a sophisticated quantitative cause-and-effect response system was developed using a three-dimensional modeling approach. It incorporates the complex three dimensional hydrodynamics, fate and transport of nutrients, as well as nutrient-algae interactions into one holistic framework. The model results show that the model performs well in reproducing the observed spatial pattern and temporal trends in water quality. The model was then applied to three total maximum daily load scenarios and two refined restoration scheme scenarios to quantify phytoplankton responses to various external load reduction intensities. The results show that the algal bloom in Lake Dianchi responds to load reduction in a complex and nonlinear way, therefore, it is necessary to apply the developed system for future load reduction and lake restoration schemes for more informed decision making and effective management.  相似文献