Natural Hazards Research最新文献

Dagiri, a community in the Gwagwalada area council, has been ravaged by floods. The most recent which took place on 25th July 2020 was devastating and had severe impacts on the community. This study focuses on the socioeconomic implications of the 2020 flood in the Dagari community. To achieve the specific objectives, a number of methodologies were employed such as map analysis, questionnaire survey, oral interviews, and site observations. Presentation of results was done using percentages, tables, bar graphs, pie charts, and photos. The land cover is mostly residential with urban infrastructures. A flood hazard map was created from which analysis revealed that about 87% of the area is at risk of flooding, though the severity of vulnerability varies from low vulnerable areas to highly vulnerable risk zones. The socioeconomic impacts were duly measured using some sustainable development indicators, and the result revealed that flooding had numerous socio-economic impacts on the community, ranging from income, education, agriculture, sanitation, infrastructures, and properties. The coping strategies adopted by some community members were also very inadequate, while a high number of them are not employing any coping strategies at all. Therefore, we recommend regulated and scientifically coordinated aggregate mining from the river and relocation of households living in high-risk flood zones. The government should invest more in flood (disaster) management with the recent challenge of climate change.

Delhi and its surrounding region are among the important intraplate seismically active regions of India. According to the Bureau of Indian Standards, it lies in seismic zone IV and is capable of generating small to moderate earthquakes. This region has also experienced moderate to large earthquakes in the past due to its proximity to the Himalayan arc and its own tectonics. There is an urgent need to assess the source characteristics of earthquakes and their scaling relationships for a reliable and accurate estimation of seismic hazard. Source parameters and their scaling relations have been estimated for this region using well-located small to moderate earthquakes (Mw 2.3–5.1) that occurred during the period from 2000 to 2020. For this purpose, we investigated three components of earthquake waveform data using the ω⁻² source model. The outcomes show the occurrence of low static stress drop (0.5–52.87 ​bars) in the Delhi region indicating approximately 57% of the events exhibit a stress drop < 10 ​bars, 27 % of events fall in the range of 10–20 ​bars, and only 16 % events exhibit stress drop > 20 ​bars. This observation suggests that the shallow subsurface of the study region may have low-strength material characteristics and a heterogeneous nature. In addition, the Zuniga parameter (ε) is estimated less than 1.0 by analyzing static and apparent stress drops, which infers the partial stress drop model fits very well in the study region. The seismic moment varies from 1.02×10¹² to 1.03×10¹⁶ ​N.m. for P-wave and 6.46×10¹¹ Nm to 7.54×10¹⁵ Nm for S-wave. The average seismic source radius lies in the range of 0.1–3.05 ​km with a ratio {r(p)/r(s)} of 1.5 ​km in the study region. The estimated values of corner frequency are comparatively lower for the S-wave (1.5–18.2 ​Hz) than for the P-wave (1.88–19.3 ​Hz) suggesting the ‘shifting properties’ of the corner frequency corroborated with the theoretical agreement. The seismic energy (E) is estimated using both P- and S-wave separately and its average value varies from 4.28×10⁶ to 6.22×10¹¹ ​J. The estimated stress drop and seismic moment demonstrate no correlation with each other. Therefore small to moderate-size earthquakes inherently follow the self-similarity behavior. The obtained scaling relationship between Seismic Moment and Corner Frequency is $M_o=7.94\ast {10}^{15}{f}_c^{-2.97}$. The derived scaling relations and source parameters are expected to provide a priori information for the assessment of seismic hazards and are useful in the simulation of strong ground motion characteristics in the region.

Landslides are the most common natural hazards and can cause casualties and damage forests, roads, water conservancy, hydropower, and other infrastructure. Road networks are essential components of critical infrastructure networks. Damage from natural disasters significantly impact the production and life in the region. It is important to evaluate the risk of road networks under landslides. In this paper, we investigate the risk of road networks under the influence of landslides in six counties adjacent to Sichuan Province and Yunnan Province by considering landslide susceptibility and road vulnerability. First, according to the characteristics of the study area, six evaluation indicators were selected for landslide susceptibility and road network vulnerability. Second, the combination weighting method is used to assign the weight of each evaluation index. Finally, the risk analysis results combining landslide susceptibility and road network vulnerability are obtained using the landslide risk formula. The research work presented in this paper can help reduce the property loss caused by landslides and realize the timely identification and protection of high-risk road sections.

Western Disturbances (WD) are significantly important weather systems causing precipitation in the Western Himalayan region during Indian Winter months. WDs have two major components-the eastward propagating upper-level trough originating in the mid-latitudes and the low-level Induced Circulation (IC) prevailing over the Northern Indo-Pak region. The present work aims to study the genesis and movement of these upper-level systems using composite analysis of 10 WD events during the Indian winter season that caused extreme precipitation over the western Himalayan region with emphasize on associative mechanisms leading to the IC. Further, we find that the Meridional Temperature Gradient (MTG) is responsible for the development of extra-tropical storms initiated by frontal genesis over the mid-latitude regions. The frontal genesis occurs due to the polar cold air outbreak (CAO) over higher latitudes, causing meandering of the jet stream and leading to the development of the upper-level perturbation that intensifies into a trough. Prior to the IC intensification, the upper-level moisture transport dominates, and during the intensification process, the combined effect of the upper-level trough and IC facilitates a drastic increase in moisture flux from the Arabian Sea at the lower levels. The moisture transport from the Arabian Sea is, therefore, a primary precursor to heavy precipitation in the Himalayan vicinity due to rapid vertical ascent and intense cloud formation because of orographic effects.

Floods are major Extreme Weather Events (EWEs) that are more frequent and intense. Floods has multifarious dire impacts on human health, but health implications of floods are limitedly examined from a gender lens, particularly in the context of developing countries, like Bangladesh. Floods periodically hit in Bangladesh. The 2017 was a catastrophic year for Bangladesh. The year experienced two consecutive floods that were more catastrophic in the last couple of decades and direly affected 24 districts of the country. The floods resulted in health stress and intensifying exposure to manifold health vulnerabilities. Our study aimed to investigate gendered health complications caused by the floods and the impacts of the confluence of the floods and vulnerabilities relating to water, sanitation, health care facilities on reproductive health. To explore gendered dimensions of health, we conducted 280 household surveys, 4 Focus Group Discussions, 4 In-Depth Interviews, and 6 Key Informant Interviews within the framework of mixed-method research in a northern flood-prone district named Jamalpur. Our findings showed that 84.6% of the respondents stated water gets polluted during floods, and 69.6% identified polluted water as a major challenge while collecting water during floods. Due to living with polluted floodwater, fever (66.4%) and diarrheal diseases (55.4%) were most common among women. In respect to reproductive health, 75% of the females reported improper menstrual management causing mental shocks and vaginal infections; over 66.4% females noted remaining without any measures. To mitigate health vulnerability, majority of the rural women (78.6%) encountered challenges – including the dearth of available medicine and poor transportation and communication. Health vulnerability also increased when poor communities failed to afford the cost of medicine because of poor economic condition and food insecurity. Consequently, our study recommends for fostering health education and the immediate deployment of health care facilities on an emergency basis to reduce health complications, especially among marginal groups (e.g., women and children). Future research can explore how the intersection of economic insecurity and flood whet differential health complications among poor and non-poor.

There has been a surge in research on adaptation planning to address climate change and its effects. This study conducted a bibliometric analysis of the keywords “adaptation planning” and “climate change” to determine the level of research being undertaken using a proposed Advanced Bibliometric Analytical Framework (ABAF). ABAF intends to overcome the inconsistency and vagueness surrounding the existing bibliometric analytical frameworks. Three types of analyses, namely performance analysis, rank analysis, and scientific mapping, were carried out on a dataset of 1087 research articles retrieved from the Web of Science database. The study found contributions from 1515 institutions and 116 countries. Most studies were published in English and Chinese languages only. An upward trend was observed in the number of publications per year, with 135 being the highest number recorded in 2021, emphasizing SDG13: Climate Action, followed by SDGs 6, 15, and 14. Findings show adaptation planning as a trending discourse in the impact reduction of climate extreme events. The results of this study can serve as a foundation for future research on adaptation planning for climate change. Additionally, ABAF can be applied in any bibliometric analytical study, and the framework could be expanded to include additional analysis typologies and metrics to enhance its comprehensiveness.

This paper presents a comprehensive seismic hazard assessment for Guwahati city, located in the northeast region of India. The earthquake data considered for the study is from 1762 to 2020, which was sourced from the published data of various seismological agencies. The fault information comprises of the latest studies and Seismotectonic Atlas (SEISAT) data. The density of earthquakes close to the faults was used to define the fault zones. The G-R relationship was utilized to calculate the seismicity parameters of the identified faults. We have used PSHA and DSHA to estimate the ground motion parameters such as peak ground acceleration and spectral acceleration at various probabilities of exceedance to calculate the level of seismic hazard. The results indicate that the seismic hazard in Guwahati is moderate to high, with several active faults in the vicinity and a high potential for strong ground motions. This study includes identifying the controlling source for Guwahati and plotting the seismic hazard curve and uniform hazard spectra for various probabilities of exceedance, which will give a basic idea of the seismic hazard of the city. The findings of this study can be used as a basis for earthquake risk reduction and mitigation strategies in Guwahati.

Over the last two decades, urban floods and their impacts have been on the rise worldwide, owing to both climatic changes and human activities. The present study examines different at-risk elements, such as residential, commercial, and critical facilities, to evaluate their multi-components of vulnerability to urban floods in Peshawar, Pakistan. Based on the impacts of urban floods, the weightage of each component of the vulnerability for the selected elements at risk is defined. This study presents and uses the modified Fisher's ideal quantity index to combine the different vulnerability components into a single value. Additionally, the Patnaik and Narayan vulnerability index is employed to generalize sector-wise vulnerabilities across the study area. The results show that the old physical infrastructure of commercial and manufacturing units in the Kohati Gate area is highly vulnerable to urban floods, while the residential units are the least susceptible due to their distanced location from the drainage system. In Hayatabad, encroachments along the torrent's sides, affecting housing and educational institutions, contributed to increased vulnerability to urban floods, despite their relatively lower physical vulnerability. The study provides a new platform for understanding the multi-components of vulnerability to urban floods and tackling the challenges posed by urban floods effectively.

Climate vulnerability in the Indian region becomes a major concern due to the frequent hydro-meteorological extreme events throughout the year. The number of extreme rainfall events (ERE) associated with monsoon, thunderstorms and short-spanned local cloudbursts which are mainly ranges from a few hours to a few days, has increased in recent decades over the subcontinent. There is a need to quantify these high impact weather events and to understand the spatio-temporal dynamics and associated physical processes for the real time prediction for pro-active disaster management. This review paper highlights the various research works carried out and suggests the need of observation, modelling efforts for simulation/prediction of the EREs in the continental India. The works starting from cloudburst in the Himalayan region (Leh, Uttarakhand, Himachal Pradesh) to the heavy rainfall in Kerala, Bangalore, Mumbai, Chennai etc. as presented by earlier researchers are being reported in this compilation. The ERE intensity and frequency distribution in India are being analyzed using IMD gridded rainfall observation for 72 years. The analysis indicates the increasing trend in the intensity of daily rainfall during the ERE in the subcontinent. The current state of research in the multi-scale study of the ERE as well as their future changes based on climate model outputs are reviewed and the challenges are also reviewed. Evaluation of the capability of the state of art meso scale models like Weather Research and Forecasting (WRF) model for the simulation of such events at high resolution using the high-performance computing and the assimilation techniques are also emphasized in the recent research in this field. Along with the impact of large-scale physical processes like El Nino Southern Oscillations (ENSO), also the sensitivity of the urbanization, topography in the simulation of the convective meso-scale events is being presented and which indicated the down-scaled data are the best tool for the ERE research. This review will surely help the interdisciplinary researchers for the extreme analysis of the high impact hydro-meteorological disaster events.

Flooding continues to ravage communities and leave societies driven by quest towards a more likely solution to flood threats. The need to accommodate both the provision of fundamental human needs and the core values and functions of the natural environment, for instance, controlling floods, puts emphasis on sustainability and illustrates the worth of ecosystem-based approach to flood risk management in locations inhabited by almost half a million people in danger of flooding. This study aims to assess the awareness of ecosystem services in the Ogun State of Nigeria and how a sustainable appropriation of the natural resources can aid local flood risk mitigation and control. The study employed a mixed-method approach through a thorough literature search to gather secondary data and a semi-structured questionnaire to source primary data from a population of 1483 participants in the study area. From the analyses, a considerable proportion of the participants (∼70%) possess a profound knowledge of flood risk and are aware of local flood abatement and ecosystem services. Based on all measured variables, only less than half of the sampled respondents identified with the idea of ecosystem, although just about 43.6% of the sampled population failed to grasp that exploring more efficient ways of using natural resources can aid in tackling flooding in the study area. With this outcome in mind, the area under study can only attain a holistic flood risk management framework by making ecosystem-based flood risk management the centrepiece of local flood risk mitigation policy and practice. This research suggests a new angle to help incorporate ecosystem service into local FRM, fortify the resilience of communities and adapt indigenous methods and assets for flood risk mitigation economy and regulation.