Designing of the perpendicular drought index   总被引：15，自引：0，他引：15  

Abduwasit Ghulam  Qiming Qin  Zhiming Zhan 《Environmental Geology》2007,52(6):1045-1052

In this paper, a simple, effective drought monitoring method is developed using two dimensional spectral space obtained from reflectance of near-infrared (NIR) and Red wavelengths. First, NIR–Red reflectance space is established using atmospheric and geometric corrected ETM+ data, which is manifested by a triangle shape and in which different surface targets possess certain spatial distribution rules. Second, perpendicular drought index (PDI) is developed on the basis of spatial characteristics of moisture distribution in NIR–Red space, as well as the relationships between PDI and soil moisture is examined. Validation work includes: comparison of PDI with in-situ drought index obtained from field measured data in the study area which includes bulk soil moisture content at different soil depths, field moisture capacity and wilting coefficient, etc.; and comparison of PDI with other recognized drought monitoring methods such as LST/NDVI and vegetation temperature condition index (VTCI). It is evident from the results that graph of PDI of field measured plots demonstrates very similar trends with ground truth drought data, LST/NDVI and VTCI. PDI is highly correlated with in-situ drought values calculated from 0 to 20 cm mean soil moisture with correlation coefficients of R ² = 0.49 (r = 0.75). This paper concludes that PDI has a potential in remote estimation of drought phenomenon as a simple, effective drought monitoring index.  相似文献   

INFLUENCE FACTORS AND PREDICTION METHOD ON FLOOD/DROUGHT DURING THE ANNUALLY FIRST RAINY SEASON IN SOUTH CHINA   总被引：1，自引：0，他引：1  

黄先香  炎利军  施能 《热带气象学报(英文版)》2007,13(1):25-28

By using the significance test of two-dimensional wind field anomalies and Monte Carlo simulation experiment scheme, the significance features of wind field anomalies are investigated in relation to flood/drought during the annually first rainy season in south China. Results show that western Pacific subtropical high and wind anomalies over the northeast of Lake Baikal and central Indian Ocean are important factors. Wind anomalies over the northern India in January and the northwest Pacific in March may be strong prediction signals. Study also shows that rainfall in south China bears a close relation to the geopotential height filed over the northern Pacific in March.  相似文献   

DIAGNOSES OF THE SEVERE DROUGHT OVER YUNNAN AREA IN THE EARLY SUMMER OF 2005     

刘瑜  赵尔旭  杨淑群  彭贵芬 《热带气象学报(英文版)》2007,13(1):93-96

High temperature and drought occurred in Yunnan province during the late spring and early summer in 2005, which was the most severe event in this region since 1950’s. Based on the observational data and relevant diagnoses, this extreme weather event was studied and discussed. The results show that the occurrence of this event could be due to the following observational facts that happened in 2005. (1) The seasonal adjustment of middle-high-leveled atmospheric circulation was delayed. (2) The cold air activity center was deviated north. (3) The onset of summer monsoon over South China Sea was delayed. (4) The tropical convection activity was much weaker than usual. (5) The subtropical high over the western Pacific was located southwestwards and relatively strong.  相似文献   

2006年全球重大天气气候事件概述   总被引：4，自引：0，他引：4  

李威  朱艳峰 《气象》2007,33(4):108-111

2006年，全球气候持续偏暖，是有器测气象记录以来的第六暖年。一次厄尔尼诺事件于2006年8月开始形成。1月，强寒潮和暴风雪袭击欧洲大部地区和日本。夏季，美国和欧洲的大部地区，中国局部地区均遭遇高温热浪天气。年内，全球各地遭受不同程度的干旱和洪涝灾害，其中美国南部和澳大利亚东南部出现严重干旱，东非地区先旱后涝，亚洲南部和南美西北部暴雨频繁。2006年，西北太平洋热带风暴和台风活动频次较常年偏少，但具有强度强、影响范围广、灾害重的特点。2006年，大西洋飓风期的热带风暴活动次数接近历史同期水平，北太平洋东部飓风期的热带风暴活动次数超过历史同期水平。  相似文献   

基于MODIS图像的植被叶面水反演与农业干旱监测     

王晓红  刘耀林  杜晓 《武汉大学学报(信息科学版)》2007,32(6):498-501

研究了应用MODIS数据,采用与植被物种无关的GVMI指数模型反演出植被水含量指标EWT,并以气象局发布的实际温度降雨数据和旱灾报告验证了植被水含量与旱灾的相关性。  相似文献   

基于MODIS数据的广西旱区干旱指数模型研究   总被引：8，自引：0，他引：8  

匡昭敏  朱伟军  杨鑫  黄永璘  何立  孙涵 《南京气象学院学报》2007,30(3):352-358

根据EOS/MODIS数据,采用植被状态指数(VCI)和温度条件指数(TCI)构建干旱指数(DI)遥感监测模型,应用于2004、2005年9-11月的广西旱情监测,制作了旱情时空变化的遥感图像,并与旱情实况数据进行对比分析,验证了干旱指数DI的有效性.通过对DI与TCI、VCI、NDVI和LST的相关性分析,发现TCI、VCI比LST、NDVI与DI的相关更显著,以TCI和VCI为因子构建的DI模型更适用于桂中旱区的旱情遥感监测.  相似文献   

基于MODIS数据的陕西地表温度监测          下载免费PDF全文

李星敏  杨文峰  张树誉  高蓓 《陕西气象》2007,(1):12-15

根据8年来跟踪调研成果,果树辨证管理技术就是一种能够适应恶劣气候变化的果树管理新学科和新技术系统,这种技术已经在苹果、桃、枣、梨、杏、李子、葡萄等果树进行实践,证明它是具有普遍意义的管理方法。特别是它控制营养生长、促进生殖生长的机制,改变了“桃三杏四梨五年”的概念,表现出生态、早产、高产、低投入、管理简化、劳动强度大大降低等诸多优势。  相似文献   

北京市地质灾害防治历程与展望     

刘连刚 《城市地质》2015,(Z1):13-17

本文在阐述北京市地质灾害的基本状况的基础上,对北京市几十年来地质灾害从被动避防到主动防灾,再到防灾体系初步形成不同阶段历程的防治工作进行了回顾总结。对北京市城市运行的地质安全.地质灾害防治与应急管理,提升公众防灾减灾意识等方面的需求进行了多角度的分析:从完善防灾保障体系、建立技术支撑体系.健全群防群治体系等几个方面,对北京市地质灾害防治进行了展望。  相似文献   

延庆县南天门崩塌灾害的治理研究     

杨少华  刘晓晓  郭英 《城市地质》2015,(Z1):195-199

本文采用了赤平投影的方法,对延庆县南天门崩塌灾害的稳定性进行分析评价,提出采用危岩清理、$5/S防护网等综合治理措施进行治理。实际情况表明,治理措施对防治崩塌灾害是切实有效的。  相似文献   

层次分析法在地灾隐患应急避险场所适宜性评价中的应用     

丁桂伶  张亮  王瑞霞  翟淑花  王强强  赵越  罗守敬 《城市地质》2015,(Z1)

地质灾害应急避险场所不仅在灾中或灾后能为灾民提供一个临时安置或生存场所,而且更是社会整合其有限资源开展防灾减灾工作的平台。本文结合北京市地质灾害应急避险现状及特征,从地质灾害应急避险场所安全性、可达性及有效性3方面,对传统的AHP方法进行优化的基础上,提出了采用层次分析法,进行避险场所适宜性评价的方法。  相似文献