DIAGNOSTIC ANALYSIS OF PERSISTENT DROUGHT/FLOOD EVENTS IN SUMMER OVER THE TWO-LAKE REGION OF CHINA     

吴贤云  丁一汇  叶成志 《热带气象学报(英文版)》2013,19(3):264-275

Based on the daily regional mean rainfall,the Z-index method is used to identify persistent flood and drought events lasting for at least 10 days over a region where Dongting Lake and Poyang Lake sit(referred to as the"two-lake region"hereafter).The National Centers for Environmental Prediction(NCEP)reanalysis data are then utilized to perform a preliminary diagnostic analysis on these events.The results indicate that the composite standardized geopotential height at 500 hPa presents two different meridional wave trains from north to south over the East Asian-Pacific region,i.e.,a"-+-"pattern for the droughts and a"+-+"pattern for the floods,respectively.The developing,maintaining and decaying phases in the drought and flood events are closely related to the intensity and location of a subtropical high and an extra-tropical blocking high.It is shown that the East Asian summer monsoon is strong(weak)with the occurrence of persistent drought(flood)events.Droughts(floods)are accompanied by a weak(strong)tropical convergent system and a strong(weak)subtropical convergent system.Furthermore,the persistent drought(flood)events are associated with a divergence(convergence)of vertically integrated water vapor flux.In the vertical profile of water vapor flux,divergence(convergence)in the mid-and lower-levels and convergence(divergence)in the higher levels are evident in the droughts(floods).Both the divergence in the droughts and the convergence in floods are strongest at 850 hPa.  相似文献   

Climate mitigation finance across developing countries: what are the major determinants?     

Aidy Halimanjaya 《Climate Policy》2013,13(2):223-252

This empirical study assesses the relationship between the characteristics of developing countries and the amount of official climate mitigation finance inflow. A two-part model and robustness checks were used to analyse 1998–2010 Rio Marker data on 180 developing countries. The results show that developing countries with higher CO₂ intensity, larger carbon sinks, lower per capita gross domestic product (GDP) and good governance tend to be selected as recipients of climate mitigation finance, and receive more of it. CO₂ emission is not used as a determinant of mitigation finance until the actual financial disbursement. Poverty aid tends to be allocated to countries with low CO₂ emissions, possibly to avoid diverting aid from poorer developing countries. However, such a diversion is unavoidable if the share of mitigation finance in climate finance and in overall official development assistance (ODA) continues to escalate. This study calls for an equitable allocation of total ODA mitigation and adaptation finance in addition to the 0.7% ODA/gross national income target, and for transparent criteria and the verification of reporting on the allocation of mitigation finance.  相似文献   

CINRAD/SA雷达灯丝电源调试与故障判定     

舒毅  舒童  杨苏勤  李欣  张福贵 《气象科技》2013,41(4):620-625

详细叙述了CINRAD/SA雷达灯丝电源控制电路的工作状态,分析了控制电路中脉宽调制器SG1525A的特性,调试了控制斩波器的脉宽调制电路和振荡器控制电路的关键测试波形,并对灯丝电源输出电压、灯丝电压保护和灯丝电流保护进行了分步调试.根据实际经验总结了在灯丝电源调试过程中出现的故障判定流程和故障排查、排除方法,旨在为雷达灯丝电源的故障处理提供参考和借鉴.  相似文献   

CINRAD/CC型雷达数据传输系统故障分析与改进方案     

梁华  高玉春  张涛  刘永强 《气象科技》2013,41(3)

对甘肃省3部CINRAD/CC型雷达近4年的雷达故障进行统计分析,作为雷达系统的主要故障部件,随着使用年限的增加,雷达数据传输系统的故障有明显的增多趋势.对引起故障的主要因素进行统计分析,提出了改进方法:基于标准网络的数据传输方式舍弃了原来的光纤系统;取消了基于光端机和复分接的通信方式,代以采用标准网络传输的通信方式;采用四创电子研发的终端软件(2.0版本),新增了集成的网络功能、用户权限功能、数据产品和图像产品全自动生成、数据文件的检索能力、语音报警等功能.改进后的雷达数据传输系统运行情况表明:网络型光纤通信系统减少了雷达数据传输故障,增强了系统的可靠性和稳定性;雷达数据的传输率和有效性也得到一定的提高,确保了新一代天气雷达的正常业务观测.  相似文献   

建立WebGIS的月球三维可视化关键技术     

邢丽平  ;左维  ;李春来 《天文研究与技术》2014,(3):299-304

嫦娥工程获得了大量月球探测数据。针对让公众用户通过网络获取月球信息,更好了解月球知识的需求,地面应用系统提出了建立基于WebGIS的月球三维可视化系统的解决方案。首先介绍了国内外三维月球的发展现状,详细分析了开发WebGIS系统的客户端和服务器端技术,重点阐述了月球空间数据模型和三维场景可视化渲染等三维GIS可视化关键技术,为建立我国的三维月球可视化系统提供了理论支持。  相似文献   

浙江中部芙蓉山花岗斑岩及包体岩石地球化学研究     

杜秀玲  汪方跃  闫海洋  顾海欧  孙贺  葛粲 《地质论评》2022,68(1):18-46

花岗岩的源区、温压条件及与其他岩石的共生组合的研究可以限定其形成构造背景,了解其形成的深部动力学过程.本文对浙江中部中生代芙蓉山花岗斑岩及其暗色包体开展了全岩主微量元素、锆石U-Pb年代学和Hf同位素、Ti温度计和全岩Sr—Nd同位素研究,探讨芙蓉山花岗斑岩的成因类型、源区特征及其与镁铁质包体之间的关系,并进一步限定其...  相似文献   

A 16 ka climate record deduced from δ^13C and C/N ratio in Qinghai Lake sediments, northeastern Tibetan Plateau     

沈吉汪勇  刘兴起Ryo Matsumoto 《中国海洋湖沼学报》2006,24(2):103-110

1 INTRODUCTION δ13C in organic matters from lacustrine sedi- ments varies with several factors including aquatic plants, vegetation type in the catchment, atmos- pheric CO2 concentration, climate (temperature and precipitation), and properties of water, …  相似文献   

Reconsideration of the age of blueschist facies metamorphism on the Seward Peninsula, Alaska, based on phengite ⁴⁰Ar/³⁹Ar results     

K. A. HANNULA  M. O. McWILLIAMS 《Journal of Metamorphic Geology》1995,13(1):125-139

Abstract ⁴⁰Ar/³⁹Ar step-heating and single-grain laser fusion ages from phengites from the polydeformed and polymetamorphosed blueschist-greenschist facies Nome Group fall into two groups. Samples from the upper part of the structural section that have experienced a relatively weak metamorphic and deformational post-blueschist facies overprint and one sample from the Cape Nome orthogneiss yield plateau ages of 116-125 Ma. More intensely overprinted samples yield hump-shaped spectra with minimum ages of 123 Ma and maximum ages of 334 Ma. Samples with hump-shaped spectra are derived from a greater structural depth than most samples with plateau ages. Unreasonably old maximum ages from some of the disturbed spectra suggest that the hump-shaped spectra result from the incorporation of excess ⁴⁰Ar. This interpretation conflicts with previous interpretations of similarly disturbed spectra from the Brooks Range, which have been argued to provide minimum ages for blueschist facies metamorphism. Since the maximum temperatures achieved by all samples were probably above the blocking temperature of Ar in phengite, the 116-125 Ma plateau ages are a minimum age for blueschist facies metamorphism on the Seward Peninsula, Alaska.  相似文献   

Spectro-imaging observations of Jupiter's 2-μm auroral emission. I. H₃ distribution and temperature     

E. Raynaud  J.-P. Maillard  J.H. Waite Jr.  P. Drossart 《Icarus》2004,171(1):133-152

We report on spectro-imaging infrared observations of Jupiter's auroral zones, acquired in October 1999 and October 2000 with the FTS/BEAR instrument at the Canada-France-Hawaii Telescope. The use of narrow-band filters at 2.09 and 2.12 μm, combined with high spectral resolution (0.2 cm⁻¹), allowed us to map emission from the H₂S₁(1) quadrupole line and from several H₃⁺ lines. The H₂ and H₃⁺ emission appears to be morphologically different, especially in the north, where the latter notably exhibits a “hot spot” near 150°-170° System III longitude. This hot spot coincides in position with the region of increased and variable hydrocarbon, FUV and X-ray emission, but is not seen in the more uniform H₂S₁(1) emission. We also present the first images of the H₂ emission in the southern polar region. The spectra include a total of 14 H₃⁺ lines, including two hot lines from the 3ν₂-ν₂ band, detected on Jupiter for the first time. They can be used to determine H₃⁺ column densities, rotational (T_rot) and vibrational (T_vib) temperatures. We find the mean T_vib of the v₂=3 state to be lower (960±50 K) than the mean T_rot in v₂=2 (1170±75 K), indicating an underpopulation of the v₂=3 level with respect to local thermodynamical equilibrium. Rotational temperatures and associated column densities are generally higher and lower, respectively, than inferred previously from ν₂ observations. This is a likely consequence of a large positive temperature gradient in the sub-microbar auroral atmosphere. While the signal-to-noise is not sufficient to take full advantage of the 2-D capabilities of the observations, the search for correlations between line intensities, T_vib and column densities, indicates that variations in line intensities are mostly due to correlated variations in the H₃⁺ column densities. The thermostatic role played by H₃⁺ at ionospheric levels may provide an explanation. The exception is the northern “hot spot,” which exhibits a T_vib about 250 K higher than other regions. A partial explanation might invoke a homopause elevation in this region, but a fully consistent scenario is not yet available. The different distributions of the H₂ and H₃⁺ emission are equally difficult to explain.  相似文献   

Rehabilitation and Sustainable Use Pattern of Rocky-desertified Land in Southwest China＇s Poverty-stricken Karst Mountainous Areas ——A Case Study in Benggu Township, Xichou County, Yunnan, China   总被引：4，自引：1，他引：3  

YANG Zisheng LIU Yansui BAO Guangjing LI Zhiguo HE Yimei 《山地科学学报》2006,3(3):237-246

The rocky desert in a karst area directly causes the lack of soil, water and forest, hence leading to the poverty there. In 1990, the villagers from the Muzhe Village in Benggu Township, Xichou County, Yunnan declared a war against rocky desert in an attempt to ask the fields for more yields. They invented a distinctive land rehabilitation and sustainable use pattern called ＂transforming heaven and earth＂ that had been practiced in Southwest China＇s karst areas. The key mechanism of the pattern was to develop terraced fields with well conserved soil, water and fertility by exploding rocks in the fields, building stone walls, gathering more soil, and improving soil quality and productivity for the fields in combination with building of irrigation facilities and roads, as well as with forestation and agriculture structure adjustment. The purpose of the pattern was to alleviate poverty in the karst areas by improving soil productivity and promoting agricultural development. A typical area was studied with the help of Participatory Rural Appraisal （PRA） and the pattern was carried out there for fifteen years, have produced excellent ecological benefits and good economic benefits. Its application in the area approved that it was a sustainable land use pattern for rocky desert areas.  相似文献