Coupling typhoon rainfall forecasting with overland-flow modeling for early warning of inundation

Taiwan suffers from an average of three or four typhoons annually, and the inundation caused by the heavy precipitation that is associated with typhoons frequently occurs in lowlands and floodplains. Potential inundation maps have been widely used as references to set up non-structural strategies for mitigating flood hazards. However, spatiotemporal rainfall distributions must be addressed to improve the accuracy of inundation forecasting for emergency response operations. This study presents a system for 24-h-ahead early warning of inundation, by coupling the forecasting of typhoon rainfall with the modeling of overland flow. A typhoon rainfall climatology model (TRCM) is introduced to forecast dynamically the spatiotemporal rainfall distribution based on typhoon tracks. The systematic scheme for early warning of inundation based on the spatiotemporal downscaling of rainfall and 2D overland-flow modeling yields not only the extent of inundation, but also the time to maximum inundation depth. The scheme is superior to traditional early warning method referring to the maximum extent and depth of inundation determined from conditional uniform rainfall. Analytical results show that coupling TRCM with an overland-flow model yields satisfactory inundation hydrographs for warning of the extent and peak time of inundation. This study also shows that the accuracy of forecasting spatiotemporal rainfall patterns determines the performance of inundation forecasting, which is critical to emergency response operations.     

Tailoring spatial reference in early warning systems to administrative units

This paper presents a novel approach for early warning systems to transform the spatial reference of dispersion models into addressable administrative units enabling an intelligible warning message reception and spatial awareness. The spatial reference along the entire information chain from sensor measurements via dispersion model to warning dissemination is discussed. Core concept behind this approach is the application of the Egenhofer-Model for analysis of binary topologic relations. It is used to identify topologic relations between dispersion model forecasts and administrative units. The result set of intersection matrices defines the relations that are counted for area classification with hazard specific parameters. Following the design for a generic and hazard-independent web service based on Open Geospatial Consortium (OGC) standards is presented in combination with results of the reference implementation.     

Role of early warning systems for sustainable agriculture in Iran

Drought is a complex phenomenon in meteorology and can affect agriculture. Its impacts vary greatly since they depend not only on the magnitude, timing, duration, and frequency of rainfall deficits but also on the differing responses of various plants to water stress. The essence of good drought management is to use this range of responses to the best advantage. Iran is one of the world’s largest and most productive suppliers of food and fiber. The objective of this study was, therefore, to gather and analyze standardized information on the Role of Early Warning Systems for Sustainable Agriculture for cereals and leguminous and industrial crops in Iran environmental zones. Annual average rainfall (mm year^?1) and ET_O (mm year^?1) are 76.56 and 3001, respectively, in stations with very dry climate; 195.41 and 2249, respectively, in stations with dry climate; 343.9 and 1351, respectively, in stations with semi-dry climate; 583.8 and 1153, respectively, in stations with semi-humid climate; and 1272 and 949, respectively, in stations with humid climate. The maximum and minimum of annual average rainfall happened in Rasht (1337 mm year^?1) and Zabol (57 mm year^?1) stations, and the maximum and minimum for annual average ET_O happened in Chabahar (3909.15 mm year^?1) and Anzali harbor (890.6 mm year^?1), respectively. Therefore, 13.63 % of stations have suitable conditions for crop productions and 86.37 % are in critical conditions.     

Ages of subsurface stratigraphic intervals in the Quaternary of Enewetak Atoll,Marshall Islands

Drill cores of Enewetak Atoll, Marshall Islands, reveal six stratigraphic intervals, numbered in downward sequence, which represent vertical coral growth during Quaternary interglaciations. Radiocarbon dates indicate that the Holocene sea transgressed the emergent reef platform by about 8000 yr B.P. The reef grew rapidly upward (about 5 to 10 mm/yr) until about 6500 yr B.P. Afterward vertical growth slowed to about 0.5 mm/yr, then lateral development became dominant during the last several thousand years. The second interval is dated at 131,000 ± 3000 yr B.P. by uranium series. This unit correlates with oxygen-isotope substage 5e and with terrace VIIa of Huon Peninsula, New Guinea, and of Main Reef-2 terrace at Atauro Island. The third interval is not dated because corals were recrystallized and it is tentatively correlated with either oxygen-isotope stages 7 or 9. The age of the fourth interval is estimated at 454,000 ± 100,000 yr B.P. from measured ${}^{234}\text{U}{}^{238}\text{U}$ activity ratios. This unit is correlated with either oxygen-isotope stage 9, 11, or 13.     

ANSYS在土洞演化预警中的应用

以桂林某高速公路为工程依托点,在全面分析现有高速公路覆盖地区的岩溶土洞的监测预警技术的基础上,选取TDR监测技术作为主要研究手段,并用ANSYS模拟了TDR监测全过程。模拟结果表明,在基岩面以上厚5.0 m左右的土层中发育有土洞且直径3.0 m以上时,可能对地面造成破坏,当土层厚度不变（5.0 m）,梁的截面尺寸一定（8 cm×6.5 cm）,土洞沿基岩面慢慢往上发育时,随着土洞发育直径的不断增大,地面变形也就越明显,且变形趋势呈缓慢的直线型; 当土洞直径为2.0 m,埋深为4.0 m,或土洞直径为4.0 m,埋深为3.0 m时,梁埋深从2.0 m开始,其变形趋于平缓;当土洞直径为3.0 m时,埋深为3.5 m,梁埋深从1.0 m到3.0 m,其变形量基本相当;当土洞直径为5.0 m,土洞顶板埋深为2.5 m,梁埋深分别为1.0 m、2.0 m,其基本保持一致,分别为6.74×10－2 m、6.75×10－2 m,即达到极限平衡状态,说明监测梁布设在距离土洞顶板2 m范围内时,可比较有效地监测到土洞变形破坏的演化趋势。      

突发性地质灾害的监测预警问题

本文主要针对突发性地质灾害的监测预警提出一套工作思路，核心是通过建立区域地质－－气象耦合分析预警示范区的途径，探索建立区域突发性群发型地质灾害的预警准则，为群测群防提供技术支撑，以促进政府，科技界和公众社会的联合行动，指导当前和今后一个时期的区域突发性地质灾害的概率预警和综合减灾工作。     

京津冀地区历史地震事件时空特征研究*

受环太平洋地震带影响,华北平原地区地震频发,尤其是处于中国首都经济圈的京津冀地区的地震事件备受关注。通过对历史文献资料及地震台网记录中的地震事件统计、分析,重建该地区地震事件历史并获取其潜在的空间分布特征及时间规律,对未来地震事件的早期预警具有重要参考意义。分析结果表明,公元前231年至公元2018年期间京津冀地区发生的1044起地震事件中,以有感地震和中强地震为主,小地震、强烈地震以及大地震发生频次较低。地震记录完整性分析结果表明,除小地震外,其他等级地震记录自公元1400年以来基本完整。在空间分布上,京津冀地区历史地震呈“T”字形分布,沿1条北西—南东走向地震带和1条北东—南西走向地震带分布。在时间上,京津冀地区地震事件呈现出阶段性的变化,在公元1480—1680年间以及1950年以来2个时间段内较为活跃,发生频率较高,频谱分析结果进一步表明地震记录存在45年的复发周期。在月际尺度上,地震事件同样存在季节性差异且多发于夏秋季节,同时地震密集区域在年内呈现出自西向东迁移的现象。最后,根据历史地震事件发生的时间规律,在未来一段时间内京津冀地区仍将处于地震活跃期,存在发生强震的风险。     

2002-2019年江西省省级地质灾害气象预警分析

江西省是我国地质灾害高发、频发的主要省区之一.2002年,原江西省国土资源厅与江西省气象局合作,首次在江西卫视天气预报节目中发布了全国第一个省级地质灾害气象预警产品.江西省省级地质灾害气象预警工作历经十余年的发展,预警等级划分主要采用图层叠加法,经历了无预警等级、五级预警等级、四级预警等级3个阶段,预警信息越来越精准.2002年至2019年年底,共发布预警信息298期,其中红色(五级)预警9期,橙色(四级)预警80期,黄色(三级)预警190期,蓝色预警15期,无等级预警4期;20022005年为预警发布尝试阶段,发布的预警信息较少;2006年始,发布的预警信息有较大程度增长.2002年至2019年年底,成功预报地质灾害事件856起,避免可能的人员伤亡8 885人,预警成效显著.对2011年以来172期预警命中率和空报率的年均值进行统计,发现命中率尚可,但空报率较高.预警工作主要存在的问题为预警信息仍为手工制作、预案对预警等级划分已出现不适用情况、未制定预警校验要求等.后期预警工作将向自动化、精细化及短临预警方向发展.     

区域滑坡泥石流灾害预警理论与方法研究

根据数年来的调查观测研究和工作实践,提出了滑坡泥石流灾害的预警分类体系,包括按物理参量划分的空间、时间与强度预警和按诱发因素参量划分的气象、地震与人类活动预警以及多参数、多因素共同作用下的综合预警。初步创建了区域性滑坡泥石流灾害暴发的两种预警理论方法,一种是基于临界过程降雨量判据图的预警方法;另一种是基于GIS的地质环境空间分析预警理论方法,通过计算预警区的滑坡泥石流灾害"发育度"、"潜势度"、"危险度"和"危害度"来实现。阐述了滑坡泥石流灾害预警的技术和行政工作程序,指出建立临界过程降雨量判据与地质环境空间分析相耦合的滑坡泥石流灾害预警理论方法是研究的新方向。     

水资源承载力预警研究进展

针对水资源承载力预警方法的研究,通过揭示水资源-社会经济-生态环境复合系统间各要素的相互作用机制,可有效地对水资源承载力的突发和异常状况进行事前行为评价和预警,是资源环境承载能力预警研究的关键组成部分。为此,借鉴有关学科领域对预警系统现有的研究成果,立足于水资源承载力预警系统的概念和机制,从诊断、预测、评价和调控方面对水资源承载力预警的主要方法进行综述,并提出水资源承载力预警未来研究重点和主要发展方面的建议,包括:① 进一步完善水资源承载力预警系统的概念界定;② 构建水资源承载力预警指标体系;③ 深入水资源承载力预警系统的整体研究;④ 重视实现水资源承载力预警动态性预测;⑤ 进一步加强水资源承载力调控措施方面的研究。     

滑坡实时监测预警系统的实验室实现

用传感器对滑坡实施监测是一种有效的监测预警手段,但由于受一些因素的限制,在实验室进行滑坡监测技术有效性的研究方面仍有一定的难度。本文以振弦式传感器为例,提出了传感器辅助机械工装以完成传感器在实验室实现滑坡监测数据模拟采集的设计思路,并通过对模拟数据进行多次测量演算了传感器及其辅助装置的可靠性。同时,为便于对监测数据进行及时有效的管理和分析,还采用VC++语言所编制的管理程序对获取的监测数据实施有效的管理和分析。结果表明,对给定信号的监测效果好,响应快,误差小,能较好地模拟滑坡现场监测。     

西南地区泥石流灾害及防灾预警

西南地区山地分布广泛，地质条件复杂，构造运动剧烈，是山地灾害严重地区之一，其中泥石流灾害尤为突出。它们严重地威胁着人民生命财产安全，给国民经济造成重大损失。为此，加强泥石流灾害的防治和研究极为必要。文章论述了西南地区泥石流的特征、形成原因和分布规律，总结当前泥石流的防治及其预测预报的方法和经验，详细地论述了西南地区泥石流灾害仿治应以预防为主，指出今后防治泥石流灾害的发展方向是成灾信息采集和传输的网络化、实时化、自动化、数字化(可视化)等，使其成灾信息能够实现实时更新，便于科学管理及信息可视，从而准确、实时地预报、预警，为泥石流灾害防治提供科学依据。     

预报预警在地质灾害防治中的应用

本文介绍了江西地质灾害气象预报模型的建立、计算方法,以及预警预报在地质灾害防治工作中获得的成功,对类似条件地区的地质灾害防治工作,具有一定的借鉴作用.     

Debris-flow Indicator for an early warning system in the Aosta valley region

Natural Hazards - Aosta Valley, an Alpine region in north-western Italy, has an early warning system (EWS) that issues hydrogeological alerts based on hydrological modelling and rainfall thresholds...     

降雨诱发区域性滑坡预报预警方法研究

论文以四川省雅安市雨城区为研究区,将逻辑回归模型引入区域降雨型滑坡预警预报,建立了同时考虑降雨强度和降雨过程的降雨临界值表达式.在滑坡危险性区划的基础上,研究提出了区域降雨型滑坡预警预报指标,包括临界值降雨指数R和滑坡发生指数L,并利用20台自动遥测雨量计和地质灾害群测群防网络,采用历史记录雨量和预报雨量,建立了区域降雨型滑坡预报预警体系.     

Monitoring and early warning of the 2012 Preonzo catastrophic rockslope failure

In this paper, we describe the investigations and actions taken to reduce risk and prevent casualties from a catastrophic 210,000 m³ rockslope failure, which occurred near the village of Preonzo in the Swiss Alps on May 15, 2012. We describe the geological predisposition and displacement history before and during the accelerated creep stage as well as the development and operation of an efficient early warning system. The failure of May 15, 2012, occurred from a large and retrogressive instability in gneisses and amphibolites with a total volume of about 350,000 m³, which formed an alpine meadow 1250 m above the valley floor. About 140,000 m³ of unstable rock mass remained in place and might collapse partially or completely in the future. The instability showed clearly visible signs of movements along a tension crack since 1989 and accelerated creep with significant hydromechanical forcing since about 2006. Because the active rockslide at Preonzo threatened a large industrial facility and important transport routes located directly at the toe of the slope, an early warning system was installed in 2010. The thresholds for prealarm, general public alarm, and evacuation were derived from crack meter and total station monitoring data covering a period of about 10 years, supplemented with information from past failure events with similar predisposition. These thresholds were successfully applied to evacuate the industrial facility and to close important roads a few days before the catastrophic slope failure of May 15, 2012. The rock slope failure occurred in two events, exposing a compound rupture plane dipping 42° and generating deposits in the midslope portion with a travel angle of 39°. Three hours after the second rockslide, the fresh deposits became reactivated in a devastating debris avalanche that reached the foot of the slope but did not destroy any infrastructure. The final run-out distance of this combined rock collapse–debris avalanche corresponded to the predictions made in the year 2004.     

GIS-PModflow联合系统在松嫩平原西部潜水环境预警中的应用

针对松嫩平原西部地下水潜水位变化对环境产生影响的现状,运用GIS-PModflow联合系统确定了地下水环境预警警戒线,采用以不至于发生土壤盐碱化的潜水临界水位作为上警戒线值,以潜水开采极限深度作为下警戒线值。在对系统模型概化的基础上,进行了潜水位的数值模拟和预报。利用GIS空间分析方法对图像数据进行栅格叠加和属性判断,通过对预报水位与警戒水位对比,进行水环境预警。结果表明,研究区2015年的警情较1999年增加,且以灌溉后潜水位上升引起的土壤次生盐渍化的警情为主。     

Comparison of the Canadian and US tornado detection and warning systems

Tornadoes are one of the most powerful and destructive weather events. The frequency of tornado occurrence is highest in North America, especially in the US Canada is second only to the US, and approximately, 80 occurrences are reported annually. Communities are impacted only when and if a tornado touches down on the ground. Early recognition of tornadoes and proper communication of warnings in the pre-touchdown phase helps the public to be ready and respond appropriately and effectively. Given that tornadoes are hard to predict and the warnings give only a very brief window of opportunity to prepare for evacuation to a secure underground or other location, each activity in the detection and warning phases is critically important. This study is focused on conducting a detailed comparison of the tornado detection and warning systems in the US and Canada. The sequences of activities and their interrelationships in the tornado detection and warning systems of each country are identified and developed as networks. A detection and warning network for Canada is developed, using Calgary as a case study, whereas a separate network is developed for the US, showing how local residents receive tornado warnings initiated by a local weather forecast office. Moreover, collaborating partners are identified, and their involvement at each level of the information flow is recognized. The two networks are compared and critically analyzed, focusing on the key issues, such as prediction/detection capabilities, warning decision-making, warning dissemination methods, and the spotters’ role. This qualitative comparison supports the recognition of key areas that need to be considered in improving the tornado detection and warning system in Canada.     

中国地质灾害气象预警初步研究

根据致灾地质环境条件和气候因素,将中国划分为7个大区、28个预警区。根据对历史时期所发生的地质灾害点和灾害发生之前15日内实际降水量及降水过程的统计分析,创建了地质灾害气象预警等级判据模式图,初步制作了各预警区的预报预警判据图;根据检索到的研究资料建立了部分预警区的判据校正图。据此,在每天收到中国国家气象中心发来的全国降雨预报数据和图像半小时内,对所预报的次日降雨过程是否诱发地质灾害和诱发灾害的空间范围、危害强度进行预报预警。2003年的试验运行表明,地质灾害气象预警在技术上是可行的,能够为主动减灾做出贡献。