1960-2017年渭河流域极端气温变化及其对区域增暖的响应   总被引：1，自引：1，他引：1  

姬霖  段克勤 《地理科学》2020,40(3):466-477

基于逐日最高和最低气温,计算1960-2017年渭河流域16项极端气温指数,发现近58 a 渭河流域极端冷指数（冰冻日数、霜冻日数、冷夜日数、冷昼日数和冷持续指数）呈下降趋势,极端暖指数（夏日日数、热夜日数、暖昼日数、暖夜日数、作物生长期和热持续指数）呈上升趋势,特别是20世纪80年代后上升速率明显加快。流域半干旱区对气候变暖的响应更敏感,主要体现在白天温度增高以及冰冻和霜冻日数减少,而半湿润区主要为夜间增暖。相比1960-2003年,2004-2017年流域平均温度升高1.75℃,暖夜/暖昼日数增加10.99/6.79 d,而霜冻/冷夜日数减少8.71/2.35 d。分析发现地形条件是影响流域极端气温空间差异的重要因素。在流域半干旱区,冷夜和冷昼日数的快速减少,有利于农作物的生长。而在相对湿度较大的半湿润区,随着夏季连续高温天气增多,高温热浪事件的危害更大。  相似文献   

Development of the Array Transient Electromagnetic System and Its Experiments   总被引：7，自引：0，他引：7  

Lin Jun  Cheng Defu  Liu Guoxing  Duan Qingming  Zhang Linhang  Yu Shengbao 《东北亚地学研究》2000,(1)

ＩｎｔｒｏｄｕｃｔｉｏｎＴｒａｎｓｉｅｎｔＥｌｅｃｔｒｏｍａｇｎｅｔｉｃ (ＴＥＭ )ｔｅｃｈｎｉｑｕｅｈａｓｂｅｅｎｆｕｒｔｈｅｒｓｔｕｄｉｅｄｉｎＣａｎａｄａ ,ＵＳＡ ,ＡｕｓｔｒａｌｉａａｎｄＦｏｒｍｅｒＳｏｖｉｅｔＵｎｉｏｎ .Ｓｉｎｃｅ 1953ｔｈｅｆｉｒ  相似文献   

Analysis of lignin-derived phenols in standard reference materials and ocean dissolved organic matter by gas chromatography/tandem mass spectrometry     

Patrick Louchouarn  Rainer M.W. Amon  Shuiwang Duan  Christina Pondell  Shaya M. Seward  Noah White 《Marine Chemistry》2010,118(1-2):85-97

A series of reference materials are proposed for intercomparison and quality control purposes during the quantification of lignin oxidation products (LOP) from diverse environmental matrices. These materials are all easily accessible and certified for diverse organic constituents (NIST and IHSS). They represent a suite of natural environmental matrices (from solids to aqueous) and are characterized by a wide range of organic carbon and lignin concentrations with abundant proportions of all major LOP. The variability of LOP concentrations and signatures for all these materials averages 3–5% and does not exceed 10%. Using these standards, a new quantification method was developed and validated for the determination of low-level CuO oxidation products using capillary gas chromatography–tandem mass spectrometry (GC/MS–MS). Tandem mass spectrometry provides both the high sensitivity and selectivity required for the identification and quantification of trace levels of dissolved lignin. The method is particularly useful for removing interference from co-eluting isotopes generated from the DOM matrix and during glucose amendment procedures of low-carbon samples. Such glucose amendment is not necessary, however, when the CuO to organic carbon weight-to-weight ratio can be kept at a value < 200–300.  相似文献   

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常金龙  钟敏  段建宾  闫昊明  江敏 《大地测量与地球动力学》2007,27(5):44-48

??????????????GRACE?????????????仯????????????????????????о???2003~2005?????????????仯?????????????????GRACE????????????????????????????????仯?????????????????????Σ?GRACE??????????????????????????仯??  相似文献   

Relation between stable isotope in monsoon precipitation in southern Tibetan Plateau and moisture transport history     

Tian  Lide  Yao  Tandong  A.  Numaguti  Duan  Keqin 《中国科学:地球科学(英文版)》2001,44(1):267-274

The moisture transport history to the south of the Tibetan Plateau was modeled using the meteorological data provided by NCEP in this paper, and the modeled results were compared with the measured δ¹⁸O in the south of the Tibetan Plateau. The relation between δ¹⁸O in precipitation in the south of the Tibetan Plateau and moisture trajectories was discussed. The results show that the extremely low δ¹⁸O in precipitation in the south of the Tibetan Plateau is always related to the moisture from the low-level sea surface evaporation. The long-distance transport of moisture also contributes to low δ¹⁸O in precipitation probably due to the rainout process during moisture transport. It is also found that low δ¹⁸O in precipitation is also related with deep layer transport of moisture, and with intensive condensation in the upper layers of the atmosphere, resulting in low δ¹⁸O because of depletion of heavy isotopes in deep condensation. However, high δ¹⁸O in precipitation whether in monsoon period or not is always companied with moisture coming from the upper layers, and the moisture is from northern or western sides of the plateau. The interpretation of the modeled results is in agreement with the isotope fractionation processes.

  相似文献   

固体潮观测资料平滑处理方法的研究     

苏其辉  段燕飞  胡毅力  吴康森 《大地测量与地球动力学》1993,(4)

固体潮观测数据在进行各种分析之前,需进行平滑处理以便消除各种突跳及错误数据。常用的平滑方法有Lecolazet数字滤波法和Nakai方法。本文讨论了各种方法的特点及存在问题。为了经济、快速而又有效地平滑数据,提出如下建议:对于高精度的观测数据,通常使用数字滤波法处理即可;在少数情况下,数据中出现连续错数,这时可取卅天为时间间隔,在上述滤波法平滑的基础上,分段对数据进行调和分析,如果某几段调和分析的误差较大,那末再进一步对这些数据段用Nakai法进行平滑处理。  相似文献   

地震数据流服务器的优化与改进     

李勇  段亚楠  樊丽云 《地震地磁观测与研究》2009,30(4):28-33

为提高测震数据流服务器的性能及安全性,提出了采用LVS服务器集群技术构建测震数据流服务器集群的方案,通过选用恰当的IP负载均衡技术及连接调度技术,较好的克服了单台服务器性能瓶颈问题,同时增强了地震数据流服务器系统的容错性及可靠性。  相似文献   

和田地震台阵勘址测量与数据分析   总被引：1，自引：1，他引：0  

段天山  范广超 《地震地磁观测与研究》2009,30(5):96-100

介绍了新疆和田地震台阵候选台址现场勘址测量及后续数据处理分析等内容,为确定台阵的最终台址和子台布局提供了可靠的数据基础。  相似文献   

不同郁闭度天山云杉林林冠截留量及穿透雨量特征研究   总被引：3，自引：0，他引：3  

郝帅  张毓涛  刘端  张洪亮  李翔 《干旱区地理》2009,32(6)

天山云杉(Picea schrenkiana var.tianschanica(Rupr.)Chen et Fu)是构成天山山地森林生态系统的主体。选取天山森林生态系统定位研究站不同郁闭度天山云杉林作为研究对象,研究了不同郁闭度条件下天山云杉林冠截留量及穿透雨量的月变化特征、林冠截留量及穿透雨量与总降雨量间的数量关系,通过研究得出结论:林冠截留率与郁闭度表现出显著正相关关系,而穿透雨比率与郁闭度表现出显著负相关关系;穿透雨量、穿透雨比率及林冠截留量的月变化与总降雨量基本一致,林冠截留率则相反;郁闭度为0.8和0.6、0.4和0.2之间的穿透雨量无显著性差异,0.8和0.6与0.4和0.2之间差异明显,林冠截留量相邻郁闭度间均无显著性差异,而不相邻郁闭度之间均差异显著;建立了穿透雨量及林冠截留量与总降雨量间的数学关系,用以定量评价该地区天山云杉林水文生态效益。  相似文献   

长江三角洲地区经济极化趋势、功能及扩展范围   总被引：2，自引：2，他引：0  

段学军  虞孝感  Josef Nipper 《地理学报(英文版)》2009,19(6):733-749

In the era of economic globalization, the concept of Economic Polarized Area comes into being as an effective vehicle to agglomerate the economic elements and sustain the economic lifeline of the region. Based on the region’s specific development mode and construction form the concept is working in such a way that it will contribute to guide the economic development of the country and will play an important role in competing with other regions or countries in the world. Due to the high speed development of the last 30 years, the Yangtze Delta Region starts to show the features of Economic Polarized Area. But, compared with other world-class Economic Polarized Areas, the economic strength and the ability of the Yangtze Delta Region to drive the country’s economic development is still very low and the competitive power is still very limited. Expanding the boundaries of the Economic Polarized Area of the Yangtze Delta may extend the economic hinterland of the core area of the Yangtze Delta Region, will lighten the pressures from the limited resource and promote the rationalization of the industrial structure in the Yangtze Delta Region’s core area. With regard to the reasonable boundaries of the Yangtze Delta Region, there are different opinions and controversial arguments in political and academic circles. Starting from the idea of increasing the competitive power and improving the economic strength of the Yangtze Delta Region, the paper firstly is discussing the requirements to become a world-class Economic Polarized Area. In a second step an analysis of functional complementation and economic collaboration between the cities of an “extended” Yangtze Delta Region has been carried out by in particular considering the feasibility of integrating these “newly included” cities. The final result of the study is, that the Region should be expanded from the number of 16 cities to 37 cities, and the appended cities should be divided up into two categories: Wenzhou, Jinhua, Yancheng, Huaian, Maanshan, Wuhu, Tongling, Chaohu, Hefei, Chuzhou, Xuancheng should be taken as Preferred Extending Area, and Suqian, Xuzhou, Lianyungang, Lishui, Quzhou, Chizhou, Anqing, Bengbu, Huangshan, Suzhou (Anhui Province) should be taken as Retained Qualification Area.  相似文献