In lieu of the paired catchment approach: Hydrologic model change detection at the catchment scale

Abstract. Daily, quasi-global (50° N–S and 180° W–E), satellite-based estimates of actual evapotranspiration at 0.25° spatial resolution have recently become available, generated by the Global Land Evaporation Amsterdam Model (GLEAM). We investigate the use of these data to improve the performance of a simple lumped catchment-scale hydrologic model driven by satellite-based precipitation estimates to generate streamflow simulations for a poorly gauged basin in Africa. In one approach, we use GLEAM to constrain the evapotranspiration estimates generated by the model, thereby modifying daily water balance and improving model performance. In an alternative approach, we instead change the structure of the model to improve its ability to simulate actual evapotranspiration (as estimated by GLEAM). Finally, we test whether the GLEAM product is able to further improve the performance of the structurally modified model. Results indicate that while both approaches can provide improved simulations of streamflow, the second approach also improves the simulation of actual evapotranspiration significantly, which substantiates the importance of making diagnostic structural improvements to hydrologic models whenever possible.

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Extending the Predictability of Hydrometeorological Flood Events Using Radar Rainfall Nowcasting

Journal of Hydrometeorology ◽

10.1175/jhm514.1 ◽

2006 ◽

Vol 7 (4) ◽

pp. 660-677 ◽

Cited By ~ 55

Author(s):

Enrique R. Vivoni ◽

Dara Entekhabi ◽

Rafael L. Bras ◽

Valeriy Y. Ivanov ◽

Matthew P. Van Horne ◽

...

Keyword(s):

Lead Time ◽

Flash Flood ◽

Spatial Scales ◽

Surface Characteristics ◽

Hydrologic Model ◽

Flood Events ◽

Catchment Scale ◽

Radar Rainfall ◽

Time Operation ◽

Forecast Lead Time

Abstract The predictability of hydrometeorological flood events is investigated through the combined use of radar nowcasting and distributed hydrologic modeling. Nowcasting of radar-derived rainfall fields can extend the lead time for issuing flood and flash flood forecasts based on a physically based hydrologic model that explicitly accounts for spatial variations in topography, surface characteristics, and meteorological forcing. Through comparisons to discharge observations at multiple gauges (at the basin outlet and interior points), flood predictability is assessed as a function of forecast lead time, catchment scale, and rainfall spatial variability in a simulated real-time operation. The forecast experiments are carried out at temporal and spatial scales relevant for operational hydrologic forecasting. Two modes for temporal coupling of the radar nowcasting and distributed hydrologic models (interpolation and extended-lead forecasting) are proposed and evaluated for flood events within a set of nested basins in Oklahoma. Comparisons of the radar-based forecasts to persistence show the advantages of utilizing radar nowcasting for predicting near-future rainfall during flood event evolution.

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Modeling Nitrate Export at the Catchment Scale using StorAge Selection Functions

10.5194/egusphere-egu2020-7967 ◽

2020 ◽

Author(s):

Tam Nguyen ◽

Rohini Kumar ◽

Stefanie R. Lutz ◽

Andreas Musolff ◽

Jan H. Fleckenstein

Keyword(s):

Time Distribution ◽

Root Zone ◽

Hydrologic Model ◽

Distributed Model ◽

Nitrate Transport ◽

Catchment Scale ◽

Near Surface ◽

Soil Zone ◽

Different Ages ◽

Nitrate Export

Catchments store and release water of different ages. The time of a water parcel remaining in contact with the catchment subsurface affects the solute dynamics in the catchment and ultimately in the stream. Catchment storage can be conceptualized as a collection of different water parcels with different ages, the so-called residence time distribution (RTD). Similarly, the distribution of water ages in streamflow at the catchment outlet, which is sampled from the RTD, is called the travel time distribution (TTD). The selection preferences for discharge can be characterized by StorAge selection (SAS) functions. In recent years, numerical experiments have shown that SAS functions are time-variant and can be approximated, for example, by the beta distribution function. SAS functions have been emerging as a promising tool for modeling catchment-scale solute export.In this study, we aim to integrate the SAS-based description of nitrate transport with the mHM-Nitrate model (Yang et al., 2018) to simulate solute transport and turnover above and below the soil zone including legacy effects. The mHM-Nitrate is a grid based distributed model with the hydrological concept taken from the mesoscale Hydrologic Model (mHM) and the water quality concept taken from the HYdrological Predictions for the Environment (HYPE) model. Here, we replaced the description of nitrate transport in groundwater from the original mHM-Nitrate with time-variant SAS-based modeling, while we kept the detailed description of turnover of organic and inorganic nitrogen in the near-surface (root zone) from mHM-Nitrate. First-order decay was used to represent biogeochemical (denitrification) processes below the root zone and in the stream. The proposed model was tested in a mixed agricultural-forested headwater catchment in the Harz Mountains, Germany. Results show that the proposed SAS augmented nitrate model (with the time-variant beta function) is able to represent streamflow and catchment nitrate export with satisfactory results (NSE for streamflow = 0.83 and for nitrate = 0.5 at the daily time step). Overall, our combined model provides a new approach for a spatially distributed simulation of nitrogen reaction processes in the soil zone and a spatially implicit simulation of transport pathways of nitrate and denitrification in the entire catchment.Yang, X., Jomaa, S., Zink, M., Fleckenstein, J. H., Borchardt, D., & Rode, M. ( 2018). A new fully distributed model of nitrate transport and removal at catchment scale. Water Resources Research, 54, 5856&#8211; 5877.

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Climate, landscape and vegetation controls of behavioral catchments on dominant runoff response and catchment travel time distribution

10.22541/au.161916191.18516719/v1 ◽

2021 ◽

Author(s):

Chatchai Jothityangkoon ◽

Haruetai Maskong

Keyword(s):

Travel Time ◽

Overland Flow ◽

Theoretical Perspective ◽

Hydrologic Model ◽

Runoff Generation ◽

Catchment Scale ◽

Physical Relationship ◽

Relative Contribution ◽

Hillslope Scale ◽

The Impact

The three dominant processes contributing to runoff as proposed by the Dunne diagram are Hortonian overland flow (HOF), Dunne overland flow (DOF) and subsurface storm flow (SSF). Using a theoretical perspective, we investigate the impact of climate, soil, topography and vegetation on catchment water balance and the probability distribution of the travel times of each runoff generation component in respect of the connected instantaneous response function (CIRF) including the interaction of a partial contributing area connecting to the outlet. A simple distributed hydrologic model is used to capture the effect of the catchment response and to estimate the CIRFs under different possible integration of combined effect of climate, soil, topography and vegetation. A set of dimensionless similarity parameters represent catchment functions and provide a quantitative explanation of the conceptual Dunne diagram. Behavioral catchments are defined from the empirical range of the Budyko curve and mainly compatible to the physical relationship as illustrated in the Dunne diagram. The results consistent with the Dunne diagram are: (1) DOF and SSF dominates in humid for behavioral sand and silt catchments, (2) HOF dominates in arid for behavioral silt and clay catchments. Inconsistent results are: (1) SSF dominates in arid for behavioral sand, silt and clay catchments, (2) HOF dominates in humid for behavioral clay catchment and (3) no dominant HOF for behavioral sand catchment. For HOF and DOF dominates, the distribution of CIRFs can be grouped into similar shapes, which depend on the relative contribution of hillslope scale and catchment scale. For SSF behavioral catchments, the shape of the CIRFs depends on the dryness index. The combined catchment CIRFs of mean travel time for runoff responses consists with the higher first peak from the HOF and/or DOF and the second peak from the SSF.

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Observed and simulated hydroclimatology using distributed hydrologic model from in-situ and multi-satellite remote sensing datasets in Lake Victoria region in East Africa

Hydrology and Earth System Sciences Discussions ◽

10.5194/hessd-7-4785-2010 ◽

2010 ◽

Vol 7 (4) ◽

pp. 4785-4816 ◽

Cited By ~ 1

Author(s):

S. I. Khan ◽

P. Adhikari ◽

Y. Hong ◽

H. Vergara ◽

T. Grout ◽

...

Keyword(s):

Remote Sensing ◽

Satellite Remote Sensing ◽

Water Cycle ◽

Lake Victoria ◽

Remote Sensing Data ◽

Hydrologic Model ◽

East African ◽

Catchment Scale ◽

Distributed Hydrologic Model

Abstract. Floods and droughts are common, recurring natural hazards in East African nations. Studies of hydro-climatology at daily, seasonal, and annual time scale is an important in understanding and ultimately minimizing the impacts of such hazards. Using daily in-situ data over the last two decades combined with the recently available multiple-years satellite remote sensing data, we analyzed and simulated, with a distributed hydrologic model, the hydro-climatology in Nzoia, one of the major contributing sub-basins of Lake Victoria in the East African highlands. The basin, with a semi arid climate, has no sustained base flow contribution to Lake Victoria. The short spell of high discharge showed that rain is the prime cause of floods in the basin. There is only a marginal increase in annual mean discharge over the last 21 years. The 2-, 5- and 10-year peak discharges, for the entire study period showed that more years since the mid 1990's have had high peak discharges despite having relatively less annual rain. The study also presents the hydrologic model calibration and validation results over the Nzoia Basin. The spatiotemporal variability of the water cycle components were quantified using a physically-based, distributed hydrologic model, with in-situ and multi-satellite remote sensing datasets. Moreover, the hydrologic capability of remote sensing data such as TRMM-3B42V6 was tested in terms of reconstruction of the water cycle components. The spatial distribution and time series of modeling results for precipitation (P), evapotranspiration (ET), and change in storage (dS/dt) showed considerable agreement with the monthly model runoff estimates and gauge observations. Runoff values responded to precipitation events that occurred across the catchment during the wet season from March to early June. The hydrologic model captured the spatial variability of the soil moisture storage. The spatially distributed model inputs, states, and outputs, were found to be useful for understanding the hydrologic behavior at the catchment scale. Relatively high flows were experienced near the basin outlet from previous rainfall, with a new flood peak responding to the rainfall in the upper part of the basin. The monthly peak runoff was observed in the months of April, May and November. The analysis revealed a linear relationship between rainfall and runoff for both wet and dry seasons. The model was found to be useful in poorly gauged catchments using satellite forcing data and showed the potential to be used not only for the investigation of the catchment scale water balance but also for addressing issues pertaining to sustainability of the resources within the catchment.

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Effects of wildfire on catchment runoff response: a modelling approach to detect changes in snow-dominated forested catchments

Hydrology Research ◽

10.2166/nh.2010.036 ◽

2010 ◽

Vol 41 (5) ◽

pp. 378-390 ◽

Cited By ~ 48

Author(s):

Jan Seibert ◽

Jeffrey J. McDonnell ◽

Richard D. Woodsmith

Keyword(s):

Change Detection ◽

Hydrological Processes ◽

Model Parameters ◽

Catchment Scale ◽

Forested Catchments ◽

Peak Flows ◽

Runoff Series ◽

Before And After ◽

Parameter Values ◽

Modelling Approach

Wildfire is an important disturbance affecting hydrological processes through alteration of vegetation cover and soil characteristics. The effects of fire on hydrological systems at the catchment scale are not well known, largely because site specific data from both before and after wildfire are rare. In this study a modelling approach was employed for change detection analyses of one such dataset to quantify effects of wildfire on catchment hydrology. Data from the Entiat Experimental Forest (Washington State, US) were used, a conceptual runoff model was applied for pre- and post-fire periods and changes were analyzed in three different ways: reconstruction of runoff series, comparison of model parameters and comparison of simulations using parameter sets calibrated to the two different periods. On average, observed post-fire peak flows were 120% higher than those modelled based on pre-fire conditions. For the post-fire period, parameter values for the snow routine indicated deeper snow packs and earlier and more rapid snowmelt. The net effect of the changes in all parameters was largely increased post-fire peak flows. Overall, the analyses show that change detection modelling provides a viable alternative to the paired-watershed approach for analyzing wildfire disturbance effects on runoff dynamics and supports discussions on changes in hydrological processes.

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Using Remotely Sensed Information to Improve Vegetation Parameterization in a Semi-Distributed Hydrological Model (SMART) for Upland Catchments in Australia

Remote Sensing ◽

10.3390/rs12183051 ◽

2020 ◽

Vol 12 (18) ◽

pp. 3051

Author(s):

Seokhyeon Kim ◽

Hoori Ajami ◽

Ashish Sharma

Keyword(s):

Time Series ◽

Soil Moisture ◽

Vegetation Dynamics ◽

Pearson Correlation ◽

Hydrologic Model ◽

Catchment Scale ◽

Simple Method ◽

Area Index ◽

The Impact ◽

Upland Catchments

Appropriate representation of the vegetation dynamics is crucial in hydrological modelling. To improve an existing limited vegetation parameterization in a semi-distributed hydrologic model, called the Soil Moisture and Runoff simulation Toolkit (SMART), this study proposed a simple method to incorporate daily leaf area index (LAI) dynamics into the model using mean monthly LAI climatology and mean rainfall. The LAI-rainfall sensitivity is governed by a parameter that is optimized by maximizing the Pearson correlation coefficient (R) between the estimated and satellite-derived LAI time series. As a result, the LAI-rainfall sensitivity is smallest for forest, shrub, and woodland regions across Australia, and increases for grasslands and croplands. The impact of the proposed method on catchment-scale simulations of soil moisture (SM), evapotranspiration (ET) and discharge (Q) in SMART was examined across six eco-hydrologically contrasted upland catchments in Australia. Results showed that the proposed method produces almost identical results compared to simulations by the satellite-derived LAI time series. In addition, the simulation results were considerably improved in nutrient/light limited catchments compared to the cases with the default vegetation parameterization. The results showed promise, with possibilities of extension to other hydrologic models that need similar specifications for inbuilt vegetation dynamics.

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Using a paired-catchment manipulation experiment to evaluate a catchment-scale biogeochemical model

The Science of The Total Environment ◽

10.1016/0048-9697(95)04965-7 ◽

1996 ◽

Vol 183 (1-2) ◽

pp. 49-66 ◽

Cited By ~ 34

Author(s):

Bernard J. Cosby ◽

Stephen A. Norton ◽

Jeffrey S. Kahl

Keyword(s):

Biogeochemical Model ◽

Catchment Scale ◽

Paired Catchment ◽

Manipulation Experiment

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Using Satellite-Based Evapotranspiration Estimates to Improve the Structure of a Simple Conceptual Rainfall-Runoff Model

10.5194/hess-2016-413 ◽

2016 ◽

Author(s):

Tirthankar Roy ◽

Hoshin V. Gupta ◽

Aleix Serrat-Capdevila ◽

Juan B. Valdes

Keyword(s):

Model Performance ◽

Hydrologic Model ◽

Actual Evapotranspiration ◽

Catchment Scale ◽

Modified Model ◽

Model Driven ◽

Alternative Approach ◽

Precipitation Estimates ◽

Daily Water ◽

Rainfall Runoff Model

Abstract. Daily, quasi-global (50° N-S and 180° W-E), satellite-based estimates of actual evapotranspiration at 0.25° spatial resolution have recently become available, generated by the Global Land Evaporation Amsterdam Model (GLEAM). We investigate use of these data to improve the performance of a simple lumped catchment scale hydrologic model driven by satellite-based precipitation estimates to generate streamflow simulations for a poorly gauged basin in Africa. In one approach, we use GLEAM to constrain the evapotranspiration estimates generated by the model, thereby modifying the daily water balance and improving model performance. In an alternative approach, we instead change the structure of the model to improve its ability to simulate actual evapotranspiration (as estimated by GLEAM). Finally, we test whether the GLEAM product is able to further improve the performance of the structurally modified model. The results suggest that the modified model can provide improved simulations of both streamflow and evapotranspiration, even if GLEAM-satellite-based evapotranspiration data are not available.

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Diffuse Source Particulate-Matter Pollution Modeling in a Semi-Urbanized Agricultural Basin in Japan Using Process-Based WEP and an Erosion-Transport Model

Water Practice & Technology ◽

10.2166/wpt.2010.051 ◽

2010 ◽

Vol 5 (3) ◽

Cited By ~ 2

Author(s):

H. L. Rajapakse ◽

H. Inomata ◽

K. Fukami

Keyword(s):

River Basin ◽

Transport Model ◽

River Basin Management ◽

Hydrologic Model ◽

Energy Budgets ◽

Material Transport ◽

Catchment Scale ◽

Nitrogen And Phosphorus ◽

Pollution Modeling ◽

Using Data

The present study aimed at further improving the process-based WEP (Water and Energy Processes) hydrologic model, by coupling a soil erosion-transport model to introduce particle-bound pollutant component. The WEP model, initially developed for the extensive analysis of water and energy budgets at catchment scale, was later enhanced by incorporating material transport component (nitrogen and phosphorus; N and P), targeting integrated river basin management and decision support. The model involved a discharge-based process to simulate both N and P, and was validated using data in Yata River Basin, Japan, considering land use, plant acreage, fertilizer loading, plant nutrient uptake and crop harvest in respective administrative units. Although the model could adequately reproduce the dissolved N (DN) component as per the measured river N concentrations at selected observation points, particulate N and P (PN, PP), and dissolved P (DP) components were not satisfactorily simulated. In the present study, an attempt was made to incorporate PN and PP transport as soil absorbed constituents, by introducing a process-based sediment erosion, transport, deposition and associated pollutant load simulation procedures. The present modeling results indicate that PN and PP loads were better correlated with suspended solids (SS) in the stream and the model forecasting capabilities are noticeably enhanced, as verified based on the results obtained for simulation years 2001-2002 using pre-collected data (SS, PN and PP), signifying major pathways of nutrient losses in the basin.

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