scholarly journals Landslides Triggered by Typhoon Morakot in Taiwan

2018 ◽  
Author(s):  
Ssu-Yao Yang ◽  
Chyan-Deng Jan ◽  
Ji-Shang Wang
Keyword(s):  
Typhoon Morakot

The strategies to DVI challenges in Typhoon Morakot

2010 ◽  
Vol 125 (5) ◽  
pp. 637-641 ◽  
Author(s):  
Chun-Yen Lin ◽  
Tsun-Ying Huang ◽  
Hsuan-Cheng Shih ◽  
Chiao-Hsuan Yuan ◽  
Liang-Ju Chen ◽  
...  
Keyword(s):  
Typhoon Morakot

Investigating the impacts of a wet typhoon on microseismicity: a case study of the 2009 typhoon Morakot in Taiwan based on a template matching catalog

2021 ◽  
Author(s):  
Qiushi Zhai ◽  
Zhigang Peng ◽  
Lindsay Y. Chuang ◽  
Yih‐Min Wu ◽  
Ya‐Ju Hsu ◽  
...  
Keyword(s):  
Template Matching ◽  
Typhoon Morakot

scholarly journals Post-disaster assessment of landslides in southern Taiwan after 2009 Typhoon Morakot using remote sensing and spatial analysis

2010 ◽  
Vol 10 (10) ◽  
pp. 2179-2190 ◽  
Author(s):  
F. Tsai ◽  
J.-H. Hwang ◽  
L.-C. Chen ◽  
T.-H. Lin
Keyword(s):  
Spatial Analysis ◽  
Change Detection ◽  
Satellite Images ◽  
Regional Scale ◽  
Typhoon Morakot ◽  
Change Detection Analysis ◽  
Detection Analysis ◽  
Disaster Assessment ◽  
Southern Taiwan ◽  
Post Disaster

Abstract. On 8 August 2009, the extreme rainfall of Typhoon Morakot triggered enormous landslides in mountainous regions of southern Taiwan, causing catastrophic infrastructure and property damages and human casualties. A comprehensive evaluation of the landslides is essential for the post-disaster reconstruction and should be helpful for future hazard mitigation. This paper presents a systematic approach to utilize multi-temporal satellite images and other geo-spatial data for the post-disaster assessment of landslides on a regional scale. Rigorous orthorectification and radiometric correction procedures were applied to the satellite images. Landslides were identified with NDVI filtering, change detection analysis and interactive post-analysis editing to produce an accurate landslide map. Spatial analysis was performed to obtain statistical characteristics of the identified landslides and their relationship with topographical factors. A total of 9333 landslides (22 590 ha) was detected from change detection analysis of satellite images. Most of the detected landslides are smaller than 10 ha. Less than 5% of them are larger than 10 ha but together they constitute more than 45% of the total landslide area. Spatial analysis of the detected landslides indicates that most of them have average elevations between 500 m to 2000 m and with average slope gradients between 20° and 40°. In addition, a particularly devastating landslide whose debris flow destroyed a riverside village was examined in depth for detailed investigation. The volume of this slide is estimated to be more than 2.6 million m3 with an average depth of 40 m.

scholarly journals A numerical study of convection in rainbands of Typhoon Morakot (2009) with extreme rainfall: roles of pressure perturbations with low-level wind maxima

2015 ◽  
Vol 15 (6) ◽  
pp. 8479-8523
Author(s):  
C.-C. Wang ◽  
H.-C. Kuo ◽  
R. H. Johnson ◽  
C.-Y. Lee ◽  
S.-Y. Huang ◽  
...  
Keyword(s):  
Wind Shear ◽  
Vertical Wind Shear ◽  
Extreme Rainfall ◽  
Vertical Wind ◽  
Cold Pool ◽  
Rear Side ◽  
Gradient Force ◽  
Typhoon Morakot ◽  
Low Level ◽  
Pressure Perturbations

Abstract. This paper investigates the formation and evolution of deep convection inside the east–west oriented rainbands associated with a low-level jet (LLJ) in Typhoon Morakot (2009). With typhoon center to the northwest of Taiwan, the westerly LLJ was resulted from the interaction of typhoon circulation with the southwest monsoon flow, which supplied the water vapor for the extreme rainfall (of ~1000 mm) over southwestern Taiwan. The Cloud-Resolving Storm Simulator with 1 km grid spacing was used to simulate the event, and it successfully reproduced the slow-moving rainbands, the embedded cells, and the dynamics of merger and back-building (BB) on 8 August as observed. Our model results suggest that the intense convection interacted strongly with the westerly LLJ that provided reversed vertical wind shear below and above the jet core. Inside mature cells, significant dynamical pressure perturbations (pd') are induced with positive (negative) pd' at the western (eastern) flank of the updraft near the surface and a reversed pattern aloft (>2 km). This configuration produced an upward directed pressure gradient force (PGF) to the rear side and favors new development to the west, which further leads to cell merger as the mature cells slowdown in eastward propagation. The strong updrafts also acted to elevate the jet and enhance the local vertical wind shear at the rear flank. Additional analysis reveals that the upward PGF there is resulted mainly by the shearing effect but also by the extension of upward acceleration at low levels. In the horizontal, the upstream-directed PGF induced by the rear-side positive pd' near the surface is much smaller, but can provide additional convergence for BB development upstream. Finally, the cold-pool mechanism for BB appears to be not important in the Morakot case, as the conditions for strong evaporation in downdrafts do not exist.

scholarly journals Discharge of landslide-induced debris flows: case studies of Typhoon Morakot in southern Taiwan

2014 ◽  
Vol 2 (1) ◽  
pp. 315-346
Author(s):  
J.-C. Chen ◽  
M.-R. Chuang
Keyword(s):  
Debris Flow ◽  
Case Studies ◽  
Debris Flows ◽  
Maximum Flow ◽  
Field Investigation ◽  
Typhoon Morakot ◽  
Flow Discharge ◽  
Modeling Software ◽  
Southern Taiwan ◽  
Deposition Depth

Abstract. Three debris-flow gullies, the Hong-Shui-Xian, Sha-Xin-Kai, and the Xin-Kai-Dafo gullies, located in the Shinfa area of southern Taiwan were selected as case studies of the discharge of landslide-induced debris flows caused by Typhoon Morakot in 2009. The inundation characteristics of the three debris flows, such as the debris-flow volume, the deposition area, maximum flow depth, and deposition depth, were collected by field investigations and simulated using the numerical modeling software FLO-2D. The discharge coefficient cb, defined as the ratio of the debris-flow discharge Qdp to the water-flow discharge Qwp, was proposed to determine Qdp, and Qwp was estimated by a rational equation. Then, cb was calibrated by a comparison between the field investigation and the numerical simulation of the inundation characteristics of debris flows. Our results showed that the values of cb range from 6 to 18, and their values are affected by the landslide ratio The empirical relationships between Qdp and Qwp were also presented.

Suggestions for large-scale, postdisaster reconstruction involving indigenous populations: a participatory approach to recovery after Typhoon Morakot

2022 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Sung Lun Tsai ◽  
Chiho Ochiai ◽  
Min Hui Tseng ◽  
Chuan Zhong Deng
Keyword(s):  
Large Scale ◽  
Community Organization ◽  
Structured Interview ◽  
Indigenous Populations ◽  
Quantitative Methodology ◽  
Typhoon Morakot ◽  
Content Type ◽  
Qualitative And Quantitative ◽  
Extent Of Damage ◽  
Post Disaster

Purpose The participatory method, a major factor for a successful post-disaster reconstruction (PDR) project, is applied in various stages of the PDR. However, the application of this method for PDR involving indigenous populations is underexplored. Therefore, this paper aims to analyze the critical factors that can influence the participatory PDR in the indigenous context. Design/methodology/approach Two large-scale, indigenous, post-disaster relocation projects after the 2009 Typhoon Morakot were selected as case studies. The qualitative and quantitative methodology (semi-structured interview and questionnaire) were applied in the research. Findings A participation-friendly policy, community organization, the extent of damage, flexibility of nongovernmental organizations, understanding of the participatory concept and mutual trust were found to be essential factors that profoundly influence participation in PDR projects. Originality/value This study contributes by providing guidelines for future participatory PDR projects, especially in the indigenous context.

Typhoon Morakot and Institutional Changes in Taiwan

2013 ◽  
pp. 61-75 ◽  
Author(s):  
Jet-Chau Wen ◽  
Shao-Yang Huang ◽  
Chi-Feng Lin ◽  
Chia-Chen Hsu ◽  
Wen-Ni Chen
Keyword(s):  
Institutional Changes ◽  
Typhoon Morakot

scholarly journals Consolidated and Undrained Ring Shear Tests on the Sliding Surface of the Hsien-du-shan Landslide in Taiwan

Geofluids ◽  
2018 ◽  
Vol 2018 ◽  
pp. 1-12 ◽  
Author(s):  
Hung-Ming Lin ◽  
Jian-Hong Wu ◽  
Erik Sunarya
Keyword(s):  
Pore Pressure ◽  
Rock Avalanche ◽  
Excess Pore Pressure ◽  
High Water Content ◽  
Sliding Surface ◽  
Shear Tests ◽  
Typhoon Morakot ◽  
Ring Shear ◽  
Ring Shear Tests ◽  
Excess Pore

A new consolidated undrained ring shear test capable of measuring the pore pressures is presented to investigate the initiation mechanism of the Hsien-du-shan rock avalanche, triggered by Typhoon Morakot, in southern Taiwan. The postpeak state of the landslide surface between the Tangenshan sandstone and the remolded landslide gouge is discussed to address the unstable geomorphological precursors observed before the landslide occurred. Experimental results show that the internal friction angle of the high water content sliding surface in the total stress state, between 25.3 and 26.1°, clarifies the reason of the stable slope prior to Typhoon Morakot. In addition, during the ring shear tests, it is observed that the excess pore pressure is generated by the shear contractions of the sliding surface. The remolded landslide gouge, sheared under the high normal stress, rendered results associated with high shear strength, small shear contraction, low hydraulic conductivity, and continuous excess pore pressure. The excess pore pressure feedback at the sliding surface may have accelerated the landslide.

Sign in / Sign up

Export Citation Format

Share Document