Contrasting seasonality of storm rainfall and flood runoff in the UK and some implications for rainfall-runoff methods of flood estimation

Abstract Using data from 520 gauging stations in Britain and gridded rainfall datasets, the seasonality of storm rainfall and flood runoff is compared and mapped. Annual maximum (AMAX) daily rainfall occurs predominantly in summer, but AMAX floods occur most frequently in winter. Seasonal occurrences of annual daily rainfall and flood maxima differ by more than 50% in dry lowland catchments. The differences diminish with increasing catchment wetness, increase with rainfalls shorter than daily duration and are shown to depend primarily on catchment wetness, as illustrated by variations in mean annual rainfall. Over the whole dataset, only 34% of AMAX daily flood events are matched to daily rainfall annual maxima (and only 20% for 6-hour rainfall maxima). The discontinuity between rainfall maxima and flooding is explained by the consideration of coincident soil moisture storage. The results have serious implications for rainfall-runoff methods of flood risk estimation in the UK where estimation is based on a depth–duration–frequency model of rainfall highly biased to summer. It is concluded that inadequate treatment of the seasonality of rainfall and soil moisture seriously reduces the reliability of event-based flood estimation in Britain.

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Multidimensional context for extreme analysis of daily streamflow, rainfall and accumulated rainfall across USA

10.5194/egusphere-egu2020-19674 ◽

2020 ◽

Author(s):

Maria Nezi ◽

Ioannis Tsoukalas ◽

Charalampos Ntigkakis ◽

Andreas Efstratiadis

Keyword(s):

Soil Moisture ◽

Daily Rainfall ◽

Extreme Rainfall ◽

Annual Rainfall ◽

Event Analysis ◽

Antecedent Soil Moisture ◽

Daily Streamflow ◽

Accumulated Rainfall ◽

Moisture Conditions ◽

Parameter Values

<p>Statistical analysis of rainfall and runoff extremes plays a crucial role in hydrological design and flood risk management. Usually this analysis is performed separately for the two processes of interest, thus ignoring their dependencies, which appear at multiple temporal scales. Actually, the generation of a flood strongly depends on soil moisture conditions, which in turn depends on past rainfall. Using daily rainfall and runoff data from about 400 catchments in USA, retrieved from the MOPEX repository, we investigate the statistical behavior of the corresponding annual rainfall and streamflow maxima, also accounting for the influence of antecedent soil moisture conditions. The latter are quantified by means of accumulated daily rainfall at various aggregation scales (i.e., from 5 up to 30 days) before each extreme rainfall and streamflow event. Analysis of maxima is employed by fitting the Generalized Extreme Value (GEV) distribution, using the L-moments method for extracting the associated parameters (shape, scale, location). Significant attention is paid for ensuring statistically consistent estimations of the shape parameter, which is empirically adjusted in order to minimize the influence of sample uncertainty. Finally, we seek for the possible correlations among the derived parameter values and hydroclimatic characteristics of the studied basins, and also depict their spatial distribution across USA.</p>

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Assimilation of Observed Soil Moisture Data in Storm Rainfall-Runoff Modeling

Journal of Hydrologic Engineering ◽

10.1061/(asce)1084-0699(2009)14:2(153) ◽

2009 ◽

Vol 14 (2) ◽

pp. 153-165 ◽

Cited By ~ 109

Author(s):

L. Brocca ◽

F. Melone ◽

T. Moramarco ◽

V. P. Singh

Keyword(s):

Soil Moisture ◽

Rainfall Runoff ◽

Soil Moisture Data ◽

Runoff Modeling ◽

Storm Rainfall

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The influence of soil moisture conditions on the spatio-temporal variability of event rainfall-runoff coefficients in UK catchments

10.5194/egusphere-egu21-6047 ◽

2021 ◽

Author(s):

Yanchen Zheng ◽

Ross Woods ◽

Jianzhu Li ◽

Ping Feng

Keyword(s):

Soil Moisture ◽

Temporal Variability ◽

Estimation Methods ◽

Runoff Coefficient ◽

Rainfall Runoff ◽

Design Flood ◽

Ungauged Catchments ◽

Flood Estimation ◽

Spatio Temporal ◽

Moisture Conditions

<p>Since the bias and uncertainties of the current design flood estimation methods for ungauged catchments are inevitable, estimation of the design flood in ungauged catchments still remains an unsolved problem. The derived distribution approach appears to be the one of the promising design flood estimation methods, as this method can improve the understanding on which processes contribute most to flood in ungauged catchments. Generally, the distribution of rainfall characteristics and lumped rainfall-runoff modelling was incorporated to estimate the flood magnitude in this method. However, we should note that rainfall is not the only driving factor of flood events. Soil moisture conditions are also an important driving factor affecting the rainfall-runoff transformation, and may even control rainfall-runoff coefficients to a higher degree than does rainfall. Hence, here we perform soil moisture analysis at national scale by employing GLDAS-Noah datasets, and link this to observed event runoff coefficients from a large sample of UK catchments. The relationship between soil moisture conditions and rainfall-runoff coefficient was explored to analyse the spatio-temporal variability of runoff coefficient. This study laid the foundation for further development of a practical derived distribution method, by considering the statistical distribution of rainfall-runoff coefficients and the influence of soil moisture conditions.</p>

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Subgrid Parameterization of the Soil Moisture Storage Capacity for a Distributed Rainfall-Runoff Model

Water ◽

10.3390/w7062691 ◽

2015 ◽

Vol 7 (12) ◽

pp. 2691-2706 ◽

Cited By ~ 4

Author(s):

Weijian Guo ◽

Chuanhai Wang ◽

Xianmin Zeng ◽

Tengfei Ma ◽

Hai Yang

Keyword(s):

Soil Moisture ◽

Storage Capacity ◽

Rainfall Runoff ◽

Soil Moisture Storage ◽

Moisture Storage ◽

Rainfall Runoff Model ◽

Runoff Model

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Rain Erosion Maps for Wind Turbines Based on Geographical Locations: A Case Study in Ireland and Britain

Journal of Bio- and Tribo-Corrosion ◽

10.1007/s40735-021-00472-0 ◽

2021 ◽

Vol 7 (1) ◽

Author(s):

K. Pugh ◽

M. M. Stack

Keyword(s):

Wind Turbine ◽

Western Europe ◽

Meteorological Data ◽

Turbine Blades ◽

Weather Conditions ◽

Annual Rainfall ◽

Wind Turbine Blades ◽

Weather Patterns ◽

The Uk

AbstractErosion rates of wind turbine blades are not constant, and they depend on many external factors including meteorological differences relating to global weather patterns. In order to track the degradation of the turbine blades, it is important to analyse the distribution and change in weather conditions across the country. This case study addresses rainfall in Western Europe using the UK and Ireland data to create a relationship between the erosion rate of wind turbine blades and rainfall for both countries. In order to match the appropriate erosion data to the meteorological data, 2 months of the annual rainfall were chosen, and the differences were analysed. The month of highest rain, January and month of least rain, May were selected for the study. The two variables were then combined with other data including hailstorm events and locations of wind turbine farms to create a general overview of erosion with relation to wind turbine blades.

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Rainfall-Runoff Modeling Using the HEC-HMS Model for the Al-Adhaim River Catchment, Northern Iraq

Hydrology ◽

10.3390/hydrology8020058 ◽

2021 ◽

Vol 8 (2) ◽

pp. 58

Author(s):

Ahmed Naseh Ahmed Hamdan ◽

Suhad Almuktar ◽

Miklas Scholz

Keyword(s):

Geographical Information Systems ◽

Hydrological Model ◽

Daily Rainfall ◽

Curve Number ◽

Geographical Information ◽

Coefficient Of Determination ◽

Rainfall Runoff ◽

Time Step ◽

River Catchment ◽

Northern Iraq

It has become necessary to estimate the quantities of runoff by knowing the amount of rainfall to calculate the required quantities of water storage in reservoirs and to determine the likelihood of flooding. The present study deals with the development of a hydrological model named Hydrologic Engineering Center (HEC-HMS), which uses Digital Elevation Models (DEM). This hydrological model was used by means of the Geospatial Hydrologic Modeling Extension (HEC-GeoHMS) and Geographical Information Systems (GIS) to identify the discharge of the Al-Adhaim River catchment and embankment dam in Iraq by simulated rainfall-runoff processes. The meteorological models were developed within the HEC-HMS from the recorded daily rainfall data for the hydrological years 2015 to 2018. The control specifications were defined for the specified period and one day time step. The Soil Conservation Service-Curve number (SCS-CN), SCS Unit Hydrograph and Muskingum methods were used for loss, transformation and routing calculations, respectively. The model was simulated for two years for calibration and one year for verification of the daily rainfall values. The results showed that both observed and simulated hydrographs were highly correlated. The model’s performance was evaluated by using a coefficient of determination of 90% for calibration and verification. The dam’s discharge for the considered period was successfully simulated but slightly overestimated. The results indicated that the model is suitable for hydrological simulations in the Al-Adhaim river catchment.

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SHETRAN and HEC HMS Model Evaluation for Runoff and Soil Moisture Simulation in the Jičinka River Catchment (Czech Republic)

Water ◽

10.3390/w13060872 ◽

2021 ◽

Vol 13 (6) ◽

pp. 872

Author(s):

Vesna Đukić ◽

Ranka Erić

Keyword(s):

Soil Moisture ◽

Czech Republic ◽

Hydrological Model ◽

Flash Flood ◽

Model Performance ◽

Rainfall Runoff ◽

The Czech Republic ◽

River Catchment ◽

Hydrological Variable ◽

Model Structures

Due to the improvement of computation power, in recent decades considerable progress has been made in the development of complex hydrological models. On the other hand, simple conceptual models have also been advanced. Previous studies on rainfall–runoff models have shown that model performance depends very much on the model structure. The purpose of this study is to determine whether the use of a complex hydrological model leads to more accurate results or not and to analyze whether some model structures are more efficient than others. Different configurations of the two models of different complexity, the Système Hydrologique Européen TRANsport (SHETRAN) and Hydrologic Modeling System (HEC-HMS), were compared and evaluated in simulating flash flood runoff for the small (75.9 km2) Jičinka River catchment in the Czech Republic. The two models were compared with respect to runoff simulations at the catchment outlet and soil moisture simulations within the catchment. The results indicate that the more complex SHETRAN model outperforms the simpler HEC HMS model in case of runoff, but not for soil moisture. It can be concluded that the models with higher complexity do not necessarily provide better model performance, and that the reliability of hydrological model simulations can vary depending on the hydrological variable under consideration.

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Mechanisms Associated with Large Daily Rainfall Events in Northeast Brazil

Journal of Climate ◽

10.1175/2010jcli3457.1 ◽

2011 ◽

Vol 24 (2) ◽

pp. 376-396 ◽

Cited By ~ 16

Author(s):

Brant Liebmann ◽

George N. Kiladis ◽

Dave Allured ◽

Carolina S. Vera ◽

Charles Jones ◽

...

Keyword(s):

Daily Rainfall ◽

Annual Rainfall ◽

Northeast Brazil ◽

Kelvin Wave ◽

Rainfall Events ◽

Independent Events ◽

Precipitation Anomalies ◽

Wave Trains ◽

Using Data ◽

Forcing Mechanisms

Abstract The mechanisms resulting in large daily rainfall events in Northeast Brazil are analyzed using data filtering to exclude periods longer than 30 days. Composites of circulation fields that include all independent events do not reveal any obvious forcing mechanisms as multiple patterns contribute to Northeast Brazil precipitation variability. To isolate coherent patterns, subsets of events are selected based on anomalies that precede the Northeast Brazil precipitation events at different locations. The results indicate that at 10°S, 40°W, the area of lowest annual rainfall in Brazil, precipitation occurs mainly in association with trailing midlatitude synoptic wave trains originating in either hemisphere. Closer to the equator at 5°S, 37.5°W, an additional convection precursor is found to the west, with a spatial structure consistent with that of a Kelvin wave. Although these two sites are located within only several hundred kilometers of each other and the midlatitude patterns that induce precipitation appear to be quite similar, the dates on which large precipitation anomalies occur at each location are almost entirely independent, pointing to separate forcing mechanisms.

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The Wet and Dry Spells across India during 1951–2007

Journal of Hydrometeorology ◽

10.1175/2009jhm1161.1 ◽

2010 ◽

Vol 11 (1) ◽

pp. 26-45 ◽

Cited By ~ 36

Author(s):

Nityanand Singh ◽

Ashwini Ranade

Keyword(s):

Climate Change ◽

Rainfall Intensity ◽

Total Duration ◽

Daily Rainfall ◽

Annual Rainfall ◽

Change Scenario ◽

Monsoon Period ◽

Northwestern India ◽

Area Of Interest ◽

Dry Spells

Abstract Characteristics of wet spells (WSs) and intervening dry spells (DSs) are extremely useful for water-related sectors. The information takes on greater significance in the wake of global climate change and climate-change scenario projections. The features of 40 parameters of the rainfall time distribution as well as their extremes have been studied for two wet and dry spells for 19 subregions across India using gridded daily rainfall available on 1° latitude × 1° longitude spatial resolution for the period 1951–2007. In a low-frequency-mode, intra-annual rainfall variation, WS (DS) is identified as a “continuous period with daily rainfall equal to or greater than (less than) daily mean rainfall (DMR) of climatological monsoon period over the area of interest.” The DMR shows significant spatial variation from 2.6 mm day−1 over the extreme southeast peninsula (ESEP) to 20.2 mm day−1 over the southern-central west coast (SCWC). Climatologically, the number of WSs (DSs) decreases from 11 (10) over the extreme south peninsula to 4 (3) over northwestern India as a result of a decrease in tropical and oceanic influences. The total duration of WSs (DSs) decreases from 101 (173) to 45 (29) days, and the duration of individual WS (DS) from 12 (18) to 7 (11) days following similar spatial patterns. Broadly, the total rainfall of wet and dry spells, and rainfall amount and rainfall intensity of actual and extreme wet and dry spells, are high over orographic regions and low over the peninsula, Indo-Gangetic plains, and northwest dry province. The rainfall due to WSs (DSs) contributes ∼68% (∼17%) to the respective annual total. The start of the first wet spell is earlier (19 March) over ESEP and later (22 June) over northwestern India, and the end of the last wet spell occurs in reverse, that is, earlier (12 September) from northwestern India and later (16 December) from ESEP. In recent years/decades, actual and extreme WSs are slightly shorter and their rainfall intensity higher over a majority of the subregions, whereas actual and extreme DSs are slightly (not significantly) longer and their rainfall intensity weaker. There is a tendency for the first WS to start approximately six days earlier across the country and the last WS to end approximately two days earlier, giving rise to longer duration of rainfall activities by approximately four days. However, a spatially coherent, robust, long-term trend (1951–2007) is not seen in any of the 40 WS/DS parameters examined in the present study.

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A reliable rainfall–runoff model for flood forecasting: review and application to a semi-urbanized watershed at high flood risk in Italy

Hydrology Research ◽

10.2166/nh.2016.037 ◽

2016 ◽

Vol 48 (3) ◽

pp. 726-740 ◽

Cited By ~ 16

Author(s):

Daniele Masseroni ◽

Alessio Cislaghi ◽

Stefania Camici ◽

Christian Massari ◽

Luca Brocca

Keyword(s):

Flood Risk ◽

Climatic Conditions ◽

Rainfall Runoff ◽

Number Of Factors ◽

Wide Range ◽

Median Volume ◽

Flood Estimation ◽

High Flood ◽

Rainfall Runoff Model ◽

Flooding Events

Many rainfall–runoff (RR) models are available in the scientific literature. Selecting the best structure and parameterization for a model is not straightforward and depends on a broad number of factors, including climatic conditions, catchment characteristics, temporal/spatial resolution and model objectives. In this study, the RR model ‘Modello Idrologico Semi-Distribuito in continuo’ (MISDc), mainly developed for flood simulation in Mediterranean basins, was tested on the Seveso basin, which is stressed several times a year by flooding events mainly caused by excessive urbanization. The work summarizes a compendium of the MISDc applications over a wide range of catchments in European countries and then it analyses the performances over the Seveso basin. The results show a good fit behaviour during both the calibration and the validation periods with a Nash–Sutcliffe coefficient index larger than 0.9. Moreover, the median volume and peak discharge errors calculated on several flood events were less than 25%. In conclusion, we can be assured that the reliability and computational speed could make the MISDc model suitable for flood estimation in many catchments of different geographical contexts and land use characteristics. Moreover, MISDc will also be useful for future support of real-time decision-making for flood risk management in the Seveso basin.

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