印度洋海啸——震颤地球与心灵的双重劫难

北京时间2004年12月26日上午印度尼西亚苏门答腊附近海域发生了里氏9级的强烈地震，地震引发的海啸波及周边多个国家，造成东南亚及印度地区20多万人死亡，还有9000多名外国游客死亡和失踪。普吉岛、巴厘岛、马尔代夫的许多岛屿，这些散落在印度洋上的珍珠不复昔日的美丽，     

基于DMC卫星影像对海啸灾情土地覆盖类型变化的分析

利用DMC卫星影像,对在2004年12月26日发生的印度洋海啸中,受灾严重的印度尼西亚亚齐特别自治区进行土地覆盖类型变化比较分析,对灾情进行评估,研究表明DMC卫星影像在灾情分析及土地覆盖类型监测等方面的应用前景。     

DMC卫星影像在海啸灾情土地覆盖类型变化分析中的应用

利用DMC卫星影像,对在2004年12月26日发生在印度洋海啸中,受灾严重的印度尼西亚亚齐特别自治区进行土地覆盖类型变化比较分析,科学客观的对灾情进行评估,从而阐述了DMC卫星影像在灾情分析及土地覆盖类型监测等方面的应用前景。     

验潮与GPS联合监测南极中山站附近海冰厚度变化

基于力学平衡原理,提出了一种联合验潮与GPS测量极区海冰厚度的新方法。由海冰上的GPS观测可得到海冰上表面高,验潮可提供海水面高,联合两种观测数据可计算得到海冰干弦高度,再结合海冰表面积雪厚度与冰雪密度数据,由力学平衡原理可构建海冰厚度的计算模型。根据这一原理,通过中国第28次南极科考队在中山站附近海冰上的实验,监测到了2012年9月22日至11月9日的海冰厚度变化。与钻孔实测冰厚相比,其总体精度达到了cm级,最大差异为8.9cm,差异的均方根为5.4cm。     

基于Geodatabase极地NetCDF验潮数据的存储与分析

针对MATLAB读取南极验潮数据所出现的问题以及南极验潮数据本身的特点,结合ArcGIS9.2推出的Multidimension Tools和Geodatabase,设计出NetCDF格式的南极验潮站数据存储和处理的一般流程,并利用MATLAB混合编程的数值计算和分析功能,有效地对南极验潮数据进行存储管理和分析,为NetCDF格式的地理数据的读取、存储提供一种解决的思路。     

基于GPS数据的地震前电离层TEC异常研究

选取印度洋区域7个IGS站,运用2004年12月26日印度洋地震前后共计25 d的GPS观测数据,计算出高时空分辨率的VTEC.综合考虑了太阳和地磁活动参数,运用统计分析的方法,详尽阐释了地震发生前TEC减小的电离层异常现象.     

中短期验潮站验潮零点不规则漂移精密处理

压力验潮仪是海洋深度测量最重要的辅助传感器之一,中、短期验潮站一般采用压力验潮仪定点布设并实现对沿岸水深测量的水位控制。受复杂海洋作业环境的综合影响,在工程实践中发现验潮零点极易出现不规则漂移,是制约水深测量成果精度的主要因素之一,但相关的探测与校正精密理论研究滞后。分析了验潮零点不规则漂移的形成机理,提出了漂移探测及校正的精密处理数学模型。通过对定海长期站和港鑫临时站以及大丰长期站和三丫子临时站等近一个月实测同步验潮数据的处理,分析了两种日平均海面计算方法对不同周期分潮的削弱效果,结果表明,本文提出的新模型适用于验潮零点不规则漂移的精密处理,经零点校正后,港鑫、三丫子等临时验潮站的水位观测数据精度由dm级提高至cm级。     

2004年印度洋海啸印尼亚齐省灾情遥感监测与分析

2004年12月底印尼苏门答腊岛西北海岸发生里氏9.0级地震,引发印度洋沿岸的印尼、斯里兰卡、泰国、印度等国家先后遭受强烈海啸。印度尼西亚亚齐省是遭受海啸灾害最严重的地区之一。为了评估海啸灾害造成的严重影响,应用遥感和地理信息系统技术,以2005-01-07英国DMC小卫星遥感影像为基础数据源,结合收集到的该地区灾前(2001年)LandsatETM 遥感影像,对亚齐省进行了监测和快速评估。监测结果表明距离震中位置较近的亚齐省苏门答腊岛西海岸遭受影响较严重,亚齐省苏门答腊岛西海岸由于距离震中位置较近遭受严重影响,而苏门答腊岛东海岸则影响较轻,受灾最严重的地区是亚齐省首府班达亚齐市附近。经统计,整个亚齐省遭受海啸严重影响的地区面积约为483km2,其中城市建成区受淹面积约为26·2km2,乡村(镇)地区受淹面积约为430·5km2。文章的最后还结合数字高程模型对海啸灾情的结果进行了分析。结果表明,绝大多数因海啸而受淹地区高程低于20m。     

印尼地震破坏力巨大将永久改变该地区地图形态

美国地球物理学家认为，2004年12月26日发生在印尼海域的地震所引发的海啸威力之大，甚至使地球在轨道运行时都发生了震颤．并且永远改变了该地区的地图形态。     

印度洋海啸灾害遥感监测与评估——以印度尼西亚亚齐省为例

介绍了运用新一代中分辨率小卫星数据———英国灾害监测小卫星(DMC,DisasterMonitoringConstellation)数据源,以印度尼西亚亚齐省为例,采用遥感数据作为信息源,对2004-12-26印尼苏门答腊岛西北海域发生的里氏9·0级的强烈地震所引发的印度洋海啸灾害进行了监测评估。所获得的小卫星图像预处理后,通过对图像中受损失地物的光谱信息分析、受损失信息与环境背景信息的对比分析,进而建立其判读标志;并在此基础上进行损失程度分级判读、统计分析等,实现了从小卫星图像上对海啸灾情损失的遥感快速监测评估。其监测评估结果为中国开展国际援助提供了客观依据,其技术方法为海啸灾害及其它灾害的遥感快速监测评价提供了技术思路,也为中国即将发射运行的灾害和环境监测预报小卫星星座及中国DMC小卫星的应用提供必要的经验及技术支持。     

由卫星测高数据观测到的印度洋海啸波高

本文介绍了利用卫星测高资料测定的印度洋地震引起的海啸波高的研究成果 ,以及卫星测高数据在对海啸灾害进行预测的应用价值。通过卫星雷达测高可观测到沿卫星星下点轨迹的相距几公里的点上的海面高 ,还提供了特别有价值的对海啸波的连续观测结果     

华南沿海地区海啸影响数值模拟与分析

应用海啸数值模拟模型（cornell multi-grid coupled Tsunami model,COMCOT）对华南沿海地区可能遭受的海啸进行模拟研究具有现实意义。基于COMCOT模型及马尼拉海沟潜在震源分段及其参数设置,模拟了不同震源引发多场海啸到达华南沿海地区的波高变化和到时特征。模拟分析发现,海啸到达中国福建省南部至广东省西部一带能够产生最大2.5 m波高的海啸波,海南岛东部沿岸也会产生最大1.5~2.0 m的海啸波,海啸传播到广西北部湾地区的最大波高在0.3 m以下;海啸波发生1.9 h后最先到达海南岛东部沿岸,2.6 h后到达香港、澳门及广东的汕尾一带地区,3.6 h后到达福建南部一带及琼州海峡地区,8.9 h以后到达北部湾地区。华南沿海不同地区海啸的首波波高和最大波波高对马尼拉海沟震源位置的敏感性存在差异性,其中广东沿海中段对马尼拉海沟震源位置最为敏感,震源断层2、断层3引发海啸在该地区的首波和最大波高接近2.5 m,而震源断层1、断层6（断层编号依据2006年美国地质调查局资料）引发海啸在该地区的首波和最大波高只在1.0 m上下。     

Optimum tracking of ship routes in 3g-WAM simulated rough weather using IRS-P4 (MSMR) analysed wind fields

Rough weather ship routing is studied using model hindcast wave climate. With the launch of IRS-P4 (OCEANSAT-I), it became possible to carry out routine wave forecasting over the Indian Ocean. The MSMR channel of the satellite gives scalar wind, which is analysed at National center for Medium Range Weather Forecasting (NCMRWF), India for converting to vector winds. The same is used as input to third generation wave model for the rough weather month of July 2000. Simulations are carried out using Cycle-4 of third generation spectral wave model WAM for regional grid system. This simulated wave climate formed the basis for computing effective ship velocity in the irregular seaway. This study gives a quantitative estimation of change in ship velocity in the open Indian Ocean for a Liberty type ship. The optimal route is charted using Dijkstra’s algorithm for minimal time path between Calcutta and Sumatra. The optimum track information has broad scope for obtaining a safer route, least time route by avoiding delay in schedule with minimum fuel consumption.     

GPS for real-time earthquake source determination and tsunami warning systems

We identify the key design aspects of a GPS-based system (and in the future, GNSS-based systems) that could contribute to real-time earthquake source determination and tsunami warning systems. Our approach is based on models of both transient and permanent displacement of GPS stations caused by large earthquakes, while considering the effect of GPS errors on inverted earthquake source parameters. Our main conclusions are that (1) the spatial pattern, magnitude, and timing of permanent displacement of GPS stations can be inverted for the earthquake source and so predict the 3D displacement field of the ocean bottom, thus providing the initial conditions for tsunami models, and (2) there are no inherently limiting factors arising from real-time orbit and positioning errors, provided sufficient near-field GPS stations are deployed. This signal could be readily exploited by GPS networks currently in place, and will be facilitated by the IGS Real-Time Project as it comes to fruition.     

Intra-Seasonal Oscillations Associated with Indian Ocean Warm Pool and Summer Monsoon Rainfall and Their Inter-Annual Variability

Sea surface temperature (SST) and wind speed (WS) derived from Multichannel Scanning Microwave Radiometer (MSMR), onboard IRS-P4 (Oceansat-1) satellite were used to generate spatially averaged (80° to 100° E & 0° to 10° S) daily data during June to September from 1999 to 2001 along with collocated outgoing long wave radiation (OLR) data from NCEP/NCAR reanalysis product. Daily rainfall data over the peninsular India during the above period was taken from the weekly weather report published by the Indian Meteorological Department. The data were then subjected to power spectral analysis. Dominant 30 to 60 days oscillations were observed over both ocean and land during all the 3 years investigated. It is quite interesting to note that the intra-seasonal oscillation with 60 days periodicity dominates in both ocean and land during 1999 and then transforms to 30 and 40 days periodicities in 2000 and 2001 respectively with a phase lag of about 25 to 30 days. It was also observed that the time-latitude section of zonally averaged OLR and TMI derived cloud liquid water data clearly depict the propagation of convection and cloud from the equator to the north at the rate of 0.75° to 1° latitude per day which corroborates well with the rate of propagation derived from the phase lag obtained between the processes occurring at the equatorial Indian Ocean and rainfall recorded at the designated land segments. The results are in good agreement with the observations made by earlier investigators.     

Impact of tsunami on aquaculture farms along the nagapattinam coast zone,Tamil Nadu,India

The tsunami waves triggered by underwater earthquake with a focal depth of 30 km near the Sumatra Island distressed the entire coast of Tamil Nadu. The worst affected coastal region is Nagapattinam, particularly from Nagoore to Vailankanni. The impact of tsunami had multidimensional effect, killing most of the fishermen communities, devastating the coastal huts and damaging the coastal aquaculture resources. The present study has been carried out to find the impact of tsunami on the aquaculture small farmland owners along the coast using pre (December 18, 2004) and post January 6, 2005) IRS P6 data. The study includes the extent of damage caused to the farms by saltwater intrusion; sand inundation, total destruction of farms. The results indicate that, there have been incredible damage caused to the farmers beyond recovery in short span of time.     

Addressing administrative units in international tsunami early warning systems: shortcomings in international geocode standards

Abstract

Administrative units reflect the territorial hierarchies established within all countries of the world. The units are addressable with geocodes that provide a bijective mapping between territories and unique identification codes. Early warning systems for natural or man-made hazards often map affected or threatened areas to administrative units to establish a spatial reference that is comprehensible to all parts of the population. Addressing these territories in an international context has several requirements, such as worldwide coverage, completeness and topicality, which must be met by geocode standards. In this paper, the practicability and suitability of international geocode standards are examined in the context of the requirements of large-scale early warning systems. This paper exposes the insufficiencies and limitations of existing geocode standards International Organization for Standardization (ISO)-3166, Second Administrative Level Boundaries data set project (SALB) and Nomenclature of the Territorial Units for Statistics (NUTS) and emphasises the suitability of the non-official hierarchical administrative subdivision codes (HASC). The analysis is framed in the context of addressing affected areas for an Indian Ocean tsunami early warning system. This system was developed within the Distant Early Warning Systems project according to the requirements of the United Nations Educational, Scientific and Cultural Organization (UNESCO) Intergovernmental Oceanic Commission for Regional Tsunami Watch Providers (RTWPs).