Rainfall Flood Research Articles

Analysis of urban flood using synthetic unit hydrograph (SUH) and flood mitigation strategies along way Halim River: a case study on Seroja street, Tanjung Senang District

In the urban area, flooding becomes the most common disaster that has not been resolved until today. The utilization of river border area into housing and lack of absorption area becomes the trigger factor of urban flooding, as what is happening around Way Halim River on Seroja street. In this area, floods often happen during the rainy season, with the latest events recorded on January 21st, 2021. Analysis of flood intensities and discharges can be parameters for the decision-making of flood mitigation strategies. This study aims to analyze the flood discharges along Way Halim River, Seroja street by comparing the flood discharges resulting from three analysis methods of Synthetic Unit Hydrograph (SUH) including Gama I SUH, Nakayasu SUH, and Snyder SUH. Finally, suitable flood mitigation strategies were also proposed in this study based on the flood discharges and rain intensities. The results showed that Nakayasu SUH had the highest peak flood discharge than Snyder SUH and Gama I SUH. Based on the results of the investigation of land suitability; and analysis of rainfall intensities and flood discharges, the proposed flood mitigation in Seroja street is by installing biopore infiltration holes along Seroja street for storing water and reducing the risk of flooding in the area.

Трансформация стока весеннего половодья и паводков в бассейне Верхней Волги под влиянием климатических изменений

An increase in the average annual air temperature in the European territory of Russia against the background of climate change leads to a decrease in water reserves in the flood-forming snow cover. At the same time, an increase in the number of transitions of air temperature through 0 ° С in the area of positive values in winter leads not only to an additional reduction in snow storage by the beginning, but also ensures an increase in the number and size of thaw floods. Changes in the intra-annual distribution of the range and intensity of precipitation entail an increase in the number and magnitude of rainfall floods. Observed transformations in the types of feeding and water regime of the rivers of the basin. Methods. The study posed the task of studying climate change on the hydrological regime of rivers in the Upper Volga basin. To solve it, methods were used to determine the methods for determining the runoff components based on the dismemberment of the hydrograph using the GrWat software package and mapping the results of the results. As part of this task, more than two thousand hydrographs were analyzed, and their long-term trends were analyzed. Results. The analysis showed that on some rivers of the region the volume of flood runoff is already comparable to the volume of flood runoff, which is not typical for the river-European type of water regime. It was found that for some rivers in the region, the volume of runoff during high water decreased by more than 50%, while the volume of runoff during the period of rainfall floods increased by more than 80%,while in the period of thaw practically by 100%.

Investigation into effects of warmer conditions on seasonal runoff and dissolved carbon fluxes in permafrost catchments in northeast China.

Eurasian permafrost serves as an important carbon pool and water resource for linked aquatic ecosystems. To investigate the effects of expected warmer climate under climate change, and also to fill the data gaps in the south margin of the Eurasian permafrost, the seasonal runoff and the associated dissolved carbon fluxes in a pair of catchments in the Great Khingan Mountains of northeast China were investigated in 2018-2019. Two similar small catchments, a south-facing (SF) and a north-facing (NF), were used to check the effects of warmer climate on the dynamics of runoff and dissolved carbon yields. The SF catchment, with a warmer condition compared to the NF catchment, presented much larger snowmelt runoff during spring and more gentle rainfall flood peaks in the summer-autumn period, but similar concentrations of dissolved carbons during both the periods. As a result, the dissolved carbon fluxes were greatly elevated during the snowmelt period. However, the runoff and carbon yield in the two catchments showed no significant difference during the summer rainfall periods, in spite of a much deeper active layer of permafrost in the SF. As indicated by two fluorescence indices, the humification (HIX) and biological index (BIX), the chemical characteristics of dissolved carbon were similar in both the snowmelt and rainfall runoff periods in the two catchments. These results emphasize that warmer climate would largely alter the seasonal runoff patterns and promote dissolved carbon export in the snowmelt period, which would lead to more unexpected ecological impacts on the aquatic systems in the south Eurasian permafrost.

Трансформация водосборных бассейнов центра Москвы под влиянием градостроительства

The center of Moscow has a lengthy and complex evolution. One of its characteristics is a dense network of underground communications of different ages (including manifolds of small rivers). Comparison between the “Leveling plan of the Moscow city” (1888) and the topographic map of Moscow (1984) doesn’t show significant changes of the city center’s relief whose absolute level’s rise hasn’t exceed 0.6 m at an average. Studying small underground rivers, such as Neglinnaya, Presnya, Chichera and Zolotoy Rozhok reveals that since the late 19th century till present time, anthropogenic changes have reduced the density of the drainage network nearly to zero and enlarged the subhorizontal surfaces. Geomorphologic processes have ceased in small urban river valleys on the surface, but suffusion-subsidence phenomena, flooding and deformation of buildings and structures intensify around rivers hidden in collectors, which causes significant damage to the urban economy. The structure and morphometry of watersheds has been simplified, and a significant part of their area has become impermeable. Therefore, despite the reduction in the slope of the terrain, flow velocity, power of the streams, and their erosive potential increased. A threat of rainfall floods still remains.

Катастрофические паводки в бассейне Ангары в 2019 ГОДУ: моделирование условий формирования и водного режима рек

The main factors of extraordinary rainfall floods formation on the Angara River left tributaries in the summer of 2019, which caused catastrophic floods in the Irkutsk oblast, were investigated. On the basis of information modeling system, the core of which is a physically based model of runoff formation ECOMAG, a spatial distributed regional hydrological model was developed. The model performance was evaluated against the longterm (35 years) data of hydrometeorological observations in the five river basins of the region. It was found that the simulated stream flow hydrographs and the peak flow values fit satisfactorily (in terms of the assigned statistical criteria) to the corresponding observations. Based on the spatial modeling results, fields of the hydrological cycle characteristics (precipitation, snow water equivalent, soil moisture) in the upper Angara basin in the summer of 2019 were analyzed. It was shown that the main factors in the formation of catastrophic floods on the Iya River were extreme precipitation combined with small losses of runoff for infiltration into preliminary saturated soils. The simulated peak flow discharge on the river near city of Tulun exceeded the historical maximum by 40% and amounted to 5640 m 3 /s. The spatial and temporal peculiarities of the two flood waves formation on the studied Angara River left tributaries in 2019 were analyzed.

Rainfall Analysis for Hyderabad and Nawabshah, Sindh, Pakistan

The climatic change has a visible impact in recent abnormal weather events, such as Pakistan’s intensification of the hydrological cycle with changing precipitation pattern, water availability periods, and weather-induced natural disasters. The rainfall flush flood of 2010 alone displaced millionσ of people and damaged properties in just one stroke. The next year, the shocking rainfall flood of 2011 in Sindh, only underscored the enormity of the challenge posed by climate change. The current paper presents the analysis carried out for one-day annual maximum rainfall for Hyderabad and Nawabshah cities, Sindh, Pakistan for the period from 1961 to 2011 using STATISTICA Software for interpolating and forecasting the rainfall time series. The maximum values of observed rainfall were 250.70mm and 256.30mm, while the minimum values were 3.0mm and 0.0mm for Hyderabad and Nawabshah respectively, while the mean of fifty-one (51) years of rainfall data is 51.96mm and 45.3 mm and the computed standard deviations were 42.693mm and 43.896mm respectively. The difference between the mean and standard deviation of one-day maximum rainfall is small, which showed the consistency of the data. The polynomial trend curved lines exhibited fluctuations in the rainfall data, which indicates a continual change in rainfall behavior. Hence, the rainfall data are subjected to a moving mean smoothing with a duration shorter than 3 years. Through these trends, the future one-day annual maximum rainfall can be predicted. The correlation of one-day annual maximum rainfall between Hyderabad and Nawabshah cities had R2 of 0.973. The computed results of return periods of 3, 5, and 10 years for one-day annual maximum rainfall for both cities revealed that the rainfall values for Hyderabad are higher.

The resilience of logjams to floods

AbstractLogjams that span the bankfull channel strongly influence hydraulics and downstream fluxes of diverse materials. Several studies quantify the longitudinal distribution of channel‐spanning logjams, but fewer studies examine changes in longitudinal distribution in response to disturbances such as floods. We use 10 years of annual surveys of a population of channel‐spanning logjams along mountain streams in the Southern Rocky Mountains. Surveys from 2010 to 2019 bracket substantial interannual variability in the snowmelt peak flow as well as a rainfall flood in 2013. We characterised the number of logjams per unit length of valley (logjam distribution density) within and between reaches designated based on longitudinally consistent channel and valley geometry. Our primary objectives are to evaluate the influences on logjam distribution density of (i) spatial variations in valley and channel geometry and (ii) temporal variations in peak annual flow. We hypothesized that logjam distribution densities are resilient to disturbance at both spatial scales. At the creek scale, logjam distribution density correlates significantly with increasing ratio of floodplain width to channel width and wood piece length to channel width. Wide, low gradient reaches with greater distribution density exhibit greater interannual variation in distribution density. These reaches lost jams during the 2013 flood but returned to pre‐flood distribution density values by the end of the study. The pattern of greater logjam distribution density in unconfined reaches relative to confined and partially confined reaches is also consistent over the period of the study. We interpret these results as indicating the resilience of logjam distributions to disturbance. The persistence of greater numbers of logjams in wide, low gradient reaches suggests that river restoration employing engineered logjams and wood reintroduction can focus most effectively on these reaches.

Rainfall Flooding in Urban Areas in the Context of Geomorphological Aspects

Flooding risk in urban areas is particularly high, due to the high population density and property values, including those of transport, residential, service and industrial infrastructure, among others. There are many reasons for flooding in urban areas; among them, direct heavy rainfall can cause special problems in risk management. In the case of random heavy rainfall, flood risk management can be supported by information about the morphology of the terrain and the degree of its sealing. In this study, we analyse methods for determining the risk of flooding in urban areas using digital terrain model (DTM) and geographic information system (GIS) tools. Predictors of precipitation floods in urban areas are defined, including the determination of flat areas, areas without outflow (non-drainage) and with large terrain height differences. The main source of information about historical rainfall floods relates to interventions by fire brigades, which constitute the basis for verifying the areas of occurrence of rainfall floods, as determined on the basis of morphological analysis of the area. Identifying the locations of rainfall flooding areas and developing accurate maps based on them are crucial for spatial planning and flood management at the local scale.

Analysis of the Effects of anticyclone Movements on Flood Rainfall in Kerman Province

Analysis of the Effects of anticyclone Movements on Flood Rainfall in Kerman Province

Flood Hazard Within the Basins of the Left Tributaries of the Angara

In June and July 2019, on the left tributaries of the Angara river there occurred catastrophic rainfall floods inflicting enormous damage and human victims. The greatest damage was experienced by the city of Tulun on the Iya river. A comprehensive characteristic is given to the 2019 floods in comparison with similar events of the historical past and from the period of instrumental observations. An analysis is made of the characteristics of the flood hazard at gauging stations: their frequency and impact. The homogeneity of the series of the peak flood runoff is estimated against the background of climate change. The objects for study were the basins of the left tributaries of Angara river: the Irkut, Kitoi, Belaya, Oka, Uda and Biryusa, with a more detailed characteristic for the Iya river basin. The floods of 2019 were formed by extreme precipitation on the previously moistened surface of the catchments. In 2019, an exceptional hydrological situation developed in terms of both flood hazard characteristics and the devastating consequences for the city of Tulun. Nevertheless, catastrophic floods of a similar magnitude also reoccurred in the historical past and during the period of instrumental observations. The situation with two extreme floods during the summer season is also not unique. The event under study cannot yet be associated with climate change. Changes in the peak rainfall runoff series are mostly insignificant, even when the approximate runoff maxima of 2019 are taken into account. The decreased flood frequency over a later period may be associated with a low-water period that ended in 2019. Therefore, similar events can be expected to recur on the rivers of Irkutsk oblast, both within the Angara basin and within the Lena and South Baikal basins.

The Impact of Urbanization and LID Technology on Hydrological Effect

Wang, J.; Zhou, L.L.; Han, P., and Li, G.X., 2020. The impact of urbanization and LID technology on hydrological effect. In: Guido Aldana, P.A. and Kantamaneni, K. (eds.), Advances in Water Resources, Coastal Management, and Marine Science Technology. Journal of Coastal Research, Special Issue No. 104, pp. 14–22. Coconut Creek (Florida), ISSN 0749-0208.The rapid development of urbanization aggravates the problems of urban rain flood disaster and water environment pollution. In order to effectively solve the above problems, the concept of LID (Low Impact Development) were proposed, studied and applied. This research took Baoshan garden sub-watershed, with significant urbanization in Jinan, China, as the study objective. Firstly, in order to clarify the impact of urbanization on hydrological effect, it was simulated and analyzed with SWMM (Storm Water Management Model) at the time node 1985, 1995, 2005 and 2015, respectively. Secondly, in order to restore the hydrological characteristics to the state undevelopment and improve the water environment, a series of LID technical measures were set in the investigated area. Lastly, in order to test the effect of LID technical measures, SWMM was adopted again to simulate the hydrological effect with the setting of LID parameters. And the simulation results after LID application were contrastively analyzed with the hydrological characteristics before and after urbanization. In conclusion, with the development of urbanization, the investigated area showed growing trend in impervious surface coverage, runoff coefficient, the total runoff volume, peak flow and runoff TSS (Total Suspended Solids) pollutant emission, declined in infiltration capacity, and appeared runoff peak ahead of time. Besides, rational utilization of LID technology could not only restore hydrological characteristics, such as the total runoff volume and peak appearance time, to the level of undevelopment, but also achieve remarkably effective control on runoff TSS pollutant emission. The research results can provide theoretical guidance for the prevention and control of rainfall flood, the utilization of rainwater resources, the treatment of water environment and the restoration of water ecology in the urbanized areas.

Rain–Induced Flood Prediction for Niger Delta Sub-Region of Nigeria Using Neural Networks

Climate change generates so many direct and indirect effects on the environment. Some of those effects have serious consequences. Rain-induced flooding is one of the direct effects of climate change and its impact on the environment is usually devastating and worrisome. Floods are one of the most commonly occurring disasters and have caused significant damage to life, including agriculture and economy. They are usually caused in areas where there is excessive downpour and poor drainage systems. The study uses Feedforward Multilayer Neural Network to perform short-term prediction of the amount of rainfall flood for the Niger Delta sub region of Nigeria given previous rainfall data for a specified period of time. The data for training and testing of the Neural Network was sourced from Weather Underground official web site https://www.wunderground.com. An iterative Methodology was used and implemented in MATLAB. We adopted multi-layer Feedforward Neural Networks. The study accurately predicts the rain-induced flood for the Niger Delta sub region of Nigeria.

Rain–Induced Flood Prediction for Niger Delta Sub-Region of Nigeria Using Neural Networks

Climate change generates so many direct and indirect effects on the environment. Some of those effects have serious consequences. Rain-induced flooding is one of the direct effects of climate change and its impact on the environment is usually devastating and worrisome. Floods are one of the most commonly occurring disasters and have caused significant damage to life, including agriculture and economy. They are usually caused in areas where there is excessive downpour and poor drainage systems. The study uses Feedforward Multilayer Neural Network to perform short-term prediction of the amount of rainfall flood for the Niger Delta sub region of Nigeria given previous rainfall data for a specified period of time. The data for training and testing of the Neural Network was sourced from Weather Underground official web site https://www.wunderground.com. An iterative Methodology was used and implemented in MATLAB. We adopted multi-layer Feedforward Neural Networks. The study accurately predicts the rain-induced flood for the Niger Delta sub region of Nigeria.

A quantitative hydroclimatic context for the European Great Famine of 1315\u20131317

The European Great Famine of 1315–1317 triggered one of the worst population collapses in European history and ranks as the single worst European famine in mortality as a proportion of population. Historical records point to torrential rainfall, land saturation, crop failure, and prolonged flooding as important causes of the famine. Here we use the tree-ring based Old World Drought Atlas (OWDA) to show that the average of each growing season preceding the Great Famine years (1314–1316) was the fifth wettest over Europe from 1300 to 2012 C.E. The spatial and temporal characteristics of our OWDA-estimated anomalies are in excellent agreement with available historical accounts. We also characterize a mode of European hydroclimate variability that is associated with the Great Famine, which we term the “Great Famine mode.” This mode emerges as the leading mode of European hydroclimate variability from 1300–2012 and is strongly associated with extreme wet and dry events in Europe over the last millennium.

Comparison of Floods Driven by Tropical Cyclones and Monsoons in the Southeastern Coastal Region of China

AbstractIncreasing evidence indicates that changes have occurred in heavy precipitation associated with tropical cyclone (TC) and local monsoon (non-TC) systems in the southeastern coastal region of China over recent decades. This leads to the following questions: what are the differences between TC and non-TC flooding, and how do TC and non-TC flooding events change over time? We applied an identification procedure for TC and non-TC floods by linking flooding to rainfall. This method identified TC and non-TC rainfall–flood events by the TC rainfall ratio (percentage of TC rainfall to total rainfall for rainfall–flood events). Our results indicated that 1) the TC rainfall–flood events presented a faster runoff generation process associated with larger flood peaks and rainfall intensities but smaller rainfall volumes, compared to that of non-TC rainfall–flood events, and 2) the magnitude of TC floods exhibited a decreasing trend, similar to the trend in the amount and frequency of TC extreme precipitation. However, the frequency of TC floods did not present obvious changes. In addition, non-TC floods decreased in magnitude and frequency while non-TC extreme precipitation showed an increase. Our results identified significantly different characteristics between TC and non-TC flood events, thus emphasizing the importance of considering different mechanisms of floods to explore the physical drivers of runoff response. Also, our results indicated that significant decreases occurred in the magnitude, but not the frequency, of floods induced by TC from the western North Pacific, which is the most active ocean basin for TC activity, and thus can provide useful information for future studies on the global pattern of TC-induced flooding.

Socio-spatial inequalities in flood resilience: Rainfall flooding in the city of Arnhem

This paper critically analyses socio-spatial inequalities associated with the shift towards flood resilience in flood risk management (FRM) and pays particular attention to the notion of ‘living with floods’ and its implications for citizens. Living with floods and the narrative of ‘surviving and thriving’ are emphasised within flood resilience literature, but such discussions often ignore the varying socio-spatial vulnerabilities and capacities of citizens. This paper undertakes an exploration of potential socio-spatial inequalities for flood resilience in the Dutch city of Arnhem, which has recently experienced rainfall flooding and is actively encouraging citizen action in FRM. The paper follows a mixed-methods approach that combines secondary data sources, semi-structured interviews, and a document analysis. Three forms of socio-spatial inequalities in flood resilience were identified in Arnhem: existing inequalities exacerbated by the shift, ‘hidden’ inequalities in vulnerability that are now relevant due to rainfall flood risk, and new inequalities in capacity to fulfil the responsibilities arising from the shift to ‘living with floods’. The paper contributes to wider discussions on the shift towards flood resilience in FRM and helps city planners to consider the interactions between vulnerability and capacity in their different neighbourhoods when allocating public resources.

Morpho-sedimentary and stratigraphic characteristics of the 2000 Yigong River landslide dam outburst flood deposits, eastern Tibetan Plateau

Sedimentary characteristics of landslide dam outburst flood deposits are distinct from those of rainfall flood deposits due to their very high hydraulic energy and sediment concentration. While they have been studied well in geological record, investigations of modern outburst flood deposits are relatively rare. Well-preserved flood deposits and landforms caused by the June 2000 landslide dam outburst flood in the Yigong River, eastern Tibet provide an opportunity to evaluate such sedimentological response to a high energy modern event. The sedimentary characteristics of boulder bars and channel evolution over c. 17 km downstream of the breach were investigated by field survey and remote sensing interpretation. The results show that the post-flood channel migrated downstream and increased in curvature. The bar shape is very little changed toward downstream, but the bar area shows a fluctuating decrease. Poorly sorted accumulations composed of massive granular gravels and boulders near the breach indicate sediment-rich bedload depositing processes occurred during rapid rising stage flows. In contrast, there are eddy bars and deposition of fine gravel with horizontally bedded laminations 17 km downstream of the dam, suggesting suspended sediment dominated deposition with a rapid loss of transport capacity. Comparison with previous hydrodynamic simulations indicates that the rates of the rising stage and the falling stage strongly affect the sedimentary characteristics of boulder bars and slackwater deposits.

Spatial Modeling of Maximum Capacity Values of Irrecoverable Rainfall Retention by Forests in a Small Watershed

When performing hydrologic calculations, the actual amount of rain precipitation falling under the tree canopies of the taiga zone is one of the most important factors in forming and estimating rainfall runoff. This is due to the fact that only a portion of rainfall reaching the soil through the forest canopy takes part in forming river runoff. At present, there is no unanimity on methods of estimating rainfall retention by the canopies of different tree species in various natural geographical zones. The existing estimation methods rely on empirical observations of net and gross rainfall rather than on the results of physical modeling of moisture on leaf surfaces in droplet form. The disadvantages of the existing methods mean that it is not possible to make a spatial estimation of rainfall captured by canopies. The purpose of this study was to map the maximum rainfall interception capacity for a small forest watershed. The authors were able to solve the following problems: (1) In situ modeling of specific water retention in droplet form on leaf surfaces of tree species of the experimental watershed in the middle taiga subzone was carried out and the specific water retention per unit leaf area was determined. Such experiments have never been conducted previously. (2) Indirect methods of estimating the leaf surface area of tree plants depending on the amount of phytomass, age and height of tree stands were developed. (3) Mapping of tree stand characteristics (such as species composition, height, canopy cover) were performed, and together with the specific rainfall interception capacity, which was determined during experiments, provided the basis for a map of maximum rainfall retention capacity by canopies, i.e., a spatial image of irrecoverable rainfall losses was obtained. Rainfall is retained on a canopy in droplet form (droplet size varies from 10.6 to 18.6 mg). Specific water retention (mass per unit leaf surface area) is determined by the leaf (needle) roughness. The overall droplet retention on canopies is determined by leaf surface area and precipitation intensity. The maximum mass of the rainfall retained on the canopies of individual deciduous trees reaches 77 kg, (3.0–4.0 mm per canopy projection area) and that of coniferous trees ranges from 24.8 to 58.0 kg (1.9 to 5.9 mm). Understanding rainfall loss values in hydrology is of key importance in distributed models of rainfall flooding. Taking into account rainfall losses due to canopy interception makes it possible to reduce the margin of error in calculations of maximum rainfall flood loss from 126% to 25%.

Impact of spring freshet flooding and summer rainfall flooding on the water quality of an alpine\xa0barrier lake

BackgroundBarrier lakes, formed by river interception, are particularly influenced by the upstream river. As such, spring freshet flooding and summer rainfall flooding due to wet precipitation (e.g. snow and rainfall) may sharply increase the concentrations of nitrogen, phosphorous, and carbon compounds in barrier lakes. Too much nutrients will lead to lake eutrophication. In this study, we used Lake Jingpo, the world’s second largest alpine barrier lake, to examine the impact of spring freshet flooding and summer rainfall flooding on its water quality by building a hydrodynamic water quality model with MIKE 21.ResultsThe MIKE 21 HD hydrodynamic model and MIKE 21 AD convection and diffusion module were calibrated using meteorological data, hydrological data, and water quality data collected in 2018. All errors were in the acceptable range. According to model simulation results, the flow velocity in Lake Jingpo is generally weak (mostly lower than 0.015 m/s), but it increases to 0.045 m/s and above during spring freshet flooding (April–May) and summer rainfall flooding (August–September), which is much higher than in other months. The flow volume of its largest inflowing river reaches 4.81 × 108 m3, 29.77 × 108 m3, and 58.4 × 108 m3 during spring freshet flooding, summer rainfall flooding, and 30-year frequency rainfall flooding period, respectively. The longest diffusion distances from the lake mouth to the downstream way are 16.3 km, 33.1 km, and 43.6 km during the spring freshet flooding, summer rainfall flooding, and 30-year frequency rainfall flooding period, respectively. A larger amount of precipitation leads to longer diffusion distances and increased concentrations of total nitrogen (TN), total phosphorous (TP), chemical oxygen demand (CODMn), and ammonia–nitrogen (NH4-N) in the lake.ConclusionsThe sudden increase in water volume during spring flooding and summer rainfall flooding led to the rapid spread of nutrients and pollutants carried by the water into the barrier lake, resulting in a deterioration of lake water quality. In addition to pollution source control measures, ecological restoration, and the construction of a buffer system in the catchment are very important measures to effectively improve the buffer capacity of barrier lakes in light of spring freshet flooding and summer rainfall flooding.

Geographical analysis of river flood hazard in Siberia

ABSTRACTSiberia is a huge and relatively sparsely populated territory in the centre of Eurasia with a harsh climate and diverse flow formation conditions. Nevertheless, it is characterized by a high flood hazard, as most of the settlements and industrial centres are located along river banks. The flood hazard can vary across space and time against a background of climatic and anthropogenic changes, as well as socio-economic factors. We carried out a geographical analysis of floods as a tool to identify the present status of flood hazard in Siberia. The analysis included: analysis of flood hazard during a period of climatic change (1985–2016); analysis of ice jams and ice dams as a specific natural factor causing floods; and identification of areas with different flood hazards using multi-scale mapping. Rainfall floods, mixed floods (due to rainfall and snowmelt) and floods resulting from ice dams are the most dangerous in Siberia. They have the highest rate of recurrence, strength of impact, and number of fatalities and displaced people. The locations of areas with different flood hazards were identified by multi-scale mapping. The highest flood hazard in Siberia is in the most populated and economically developed southern regions along the Ob, Lena, Yenisei rivers and in the Lake Baikal basin. In areas with a high flood hazard, complex measures are needed, taking into account regional peculiarities.