Frequency Of Flood Disasters Research Articles

Rainfall Runoff Modelling of Panchaganga River Using HEC-HMS Software and it's Analysis.

The present study of this project is intended on the formation of a working flood model of the river Panchaganga flood in the Kolhapur stretch which is in Maharashtra state in India. Using HEC-HMS the precipitation is used to estimate the run off along the watershed. The central aim of this project resides in the development of a calibrated working model of the 2019 floods. This model is later used to simulate the various possibilities of flood event. Rainfall Runoff Model which is a mathematical model which relates the rainfall and runoff with the use of catchment area or watershed area. Hydrological modeling can estimate for the runoff in the study area of the model by evaluating the precipitation and discharges inputs given to the HEC-HMS software. Hydrological models on the other hand estimates the surface runoff within the study area. In recent decades, India has experienced an increase in the frequency of flood disasters. Flood is a flow that overtops either hydraulic structure or river bank along a stream resulting in damage to the adjoining property or life. The primary reason behind this is the Climate change and Immense urbanization, which has resulting in alteration of basin characteristics. The development projects near riverbanks have the worst effects on a reach's ability to drain, which increases the likelihood of flood-like conditions. In this project an area of the Panchaganga river is to be taken and a flood mapping using HEC-HMS (Hydrological Modelling System) and GIS software is to be drawn. According to the drawn flood map there will be a suitable mitigation measure suggested and the effect of the suggested mitigation measure is to be modeled.

Analysis of Flood Disaster Adaptation Strategies Among People of Guma Local Government Area, Benue State, Nigeria

Abstract – One of the most important issues in flood risk management is finding a way to cope with uncertainties. Despite centuries of experience with flood management, flood disasters become more frequent and are increasing in severity due to climate change. This work examined flood disaster adaptation strategies among the people of Guma Local Government Area, Benue State. Data on the demographic characteristics of respondents, flood frequency, duration, and impact of flood disasters on people of the study area, as well as flood mitigation and adaptation strategies, were obtained using a questionnaire. A total of 380 respondents were sampled using random sampling. The data were analyzed using frequencies and percentages and presented in tables. Results revealed that the respondents are susceptible to the impact of flood disasters due to their socio-demographic characteristics. Furthermore, the results show that the frequency of flood disasters is biennial while its duration is between one to two weeks. Flood also impacts both directly and indirectly, involving mostly destruction of farm crops, and disruption of transportation. Lastly, the results show that the respondents mostly clear-filled/blocked drainages around them to mitigate the impact of flood disasters and many of the respondents construct wooden bridges across drainages/gutters in order to adapt to flooding in their areas. The study recommends that non-flood-sensitive economic activities should be embraced to mitigate the impact of flooding in the study area. There should also be public enlightenment and sensitization on the need to adopt both structural and nonstructural measures of adapting to flood disasters as climate change continues to trigger more severe, and frequent floods.

Cross-border evacuation and intermunicipal cooperation during large-scale flood disasters

The frequency of flood disasters has increased in recent years, leading to significant damage worldwide. Developing global risk-reduction strategies, such as cross-border evacuation, is necessary. The effective spatial range for intermunicipal cooperation is an important factor in implementing cross-border evacuation. Thus, this study investigates the effects of cross-border evacuation in large-scale floods by comparing inner and cross-border evacuation scenarios using GIS network analysis. The spatial range of inter-municipal cooperation is clarified based on a case study from Japan. The major findings are as follows: First, cross-border evacuation has the potential to reduce the evacuation time in many cities. Specifically, out-of-city shelters constitute the nearest shelter option for 24% of evacuees. Cross-border evacuation may reduce evacuation time by up to 14%. Second, cross-border evacuation is unsuitable for certain cities because of congestion at the boundaries. Third, community detection that finds the subnetwork with strong dependency between cities can suggest the effective spatial range for inter-municipal cooperation. Fourth, the shelters and route of cross-border evacuation considerably differ with inner evacuation. The evacuation plan requires specific guidance. This study helps identify the areas that would benefit the most from implementing cross-border evacuation and contributes to developing a wide-area evacuation plan in cooperation with neighboring cities.

Spatial–temporal characteristics of drought and flood disasters in Yunnan Province on the margin of the Tibetan Plateau over the past 620 years

AbstractDrought and flood disasters (DFD) are the most important natural disasters in the Indian monsoon (IM) region, and often occur in the same year. This makes it difficult to accurately study the characteristics of DFD using the evaluation grades of disasters. Based on the statistical analysis of historical drought and flood data in Yunnan Province, combined with anomaly accumulation values, sliding t tests and wavelet analyses, the spatial–temporal characteristics and the possible dynamic mechanisms of the DFD in Yunnan Province are analysed during the past 620 years. The results show that the frequency of flood disasters in Yunnan Province was slightly higher than that of drought disasters, and disaster frequency has gradually increased over the past 620 years, especially after 1750 AD. The variations characteristics of the drought and flood index (DFI) have 2 ~ 10 year quasi‐periodic signal in the east and west regions of the Yunling‐Ailao Mountains, and they are consistent with the environmental records of tree rings and lacustrine deposits in the region. The DFD of the IM region may be influenced mainly by solar activity and El Niño‐Southern Oscillation (ENSO) on a century scale, and frequent human activities enhance the impact of DFD, especially in the east region of the Yunling‐Ailao Mountains. The results provide a method to further understand the mechanism and trends of drought and flood disasters in the monsoon region on a century scale.

Research on intelligent prediction and zonation of basin-scale flood risk based on LSTM method.

Global climate change and human activities aggravate the frequency of flood disasters. Flood risk includes natural flood risk and risk of economic and social disasters, which is displayed intuitively by flood risk zonation maps. In this paper, we take the disaster-causing factors, the disaster environment, the disaster-bearing body, and the disaster prevention and mitigation capability into consideration comprehensively. Eleven influencing indexes including annual maximum 3-day rainfall and rainfall in flood season are selected, and the virtual sown area of crops is innovated. Taking the Huaihe River Basin (HRB) as the research area, the flood risk prediction of the basin is explored by using the long short-term memory (LSTM). The results show that LSTM can be successfully applied to flood risk prediction. The short-term prediction results of the model are good, and the area where the risk is seriously underestimated (the high and very high risk are identified as the very low risk) accounts for only 0.98% of the total basin on average. The prediction results can be used as a reference for watershed management organizations, so as to guide future flood disaster prevention.

Recent and Future Climate Change in Northwest China

As a consequence of global warming and an enhanced water cycle, the climate changed in northwest China, most notably in the Xinjiang area in the year 1987. Precipitation, glacial melt water and river runoff and air temperature increased continuously during the last decades, as did also the water level of inland lakes and the frequency of flood disasters. As a result, the vegetation cover is improved, number of days with sand-dust storms reduced. From the end of the 19th century to the 1970s, the climate was warm and dry, and then changed to warm and wet. The effects on northwest China can be classified into three classes by using the relation between precipitation and evaporation increase. If precipitation increases more than evaporation, runoff increases and lake water levels rise. We identify regions with: (1) notable change, (2) slight change and (3) no change. The future climate for doubled CO2 concentration is simulated in a nested approach with the regional climate model-RegCM2. The annual temperature will increase by 2.7 ^ C and annual precipitation by 25%. The cooling effect of aerosols and natural factors will reduce this increase to 2.0 ^C and 19% of precipitation. As a consequence, annual runoff may increase by more than 10%.

Flood management under climatic variability and its future perspective in Japan

Devastating magnitudes of flood disasters have been occurring in various areas of Japan, and their impact has been increasing in recent years. Looking ahead, it is foreseen that rainfall and its patterns will be altered due to the climate change accompanied by global warming, and there is concern that the intensity and frequency of flood disasters might be exacerbated. This paper aims to introduce flood characteristics and management policies in Japan that have been undertaken for a long time in order to mitigate these recurrent flood disasters. It also highlights extremely devastating floods in some areas that occurred under recent climate variability, and to address the progress in the assessment of hydro-meteorological tendencies and in the promotion of dialogue among climatologists and hydrologists. Lastly, a new initiative to establish an intemational centre on water-related hazards and its risk management is presented.