scholarly journals Variability of water regime in the forested experimental catchments

2010 ◽  
Vol 4 (Special Issue 2) ◽  
pp. S93-S101 ◽  
Author(s):  
J. Buchtele ◽  
M. Tesař ◽  
P. Krám
Keyword(s):  
Soil Moisture ◽  
Annual Cycle ◽  
Vegetation Cover ◽  
Water Regime ◽  
Time Span ◽  
Rainfall Runoff ◽  
Regime Changes ◽  
Significant Phenomenon ◽  
Demand Variability

The water regime variability in most catchments is frequently influenced not only by the changes of the vegetation cover in the annual cycle but also by its development in the time span of decades. That means that the resulting evapotranspiration depends not only on the actual climatic situation but also on the soil moisture. The simulations of the rainfall-runoff process have been used with the intention to follow the possible role of the developing land cover. The differences between the observed and simulated flows in relatively long periods can be considered as an appropriate tool for the assessment of the water regime changes, in which the evapotranspiration demand variability is a significant phenomenon.

The time variability of evapotranspiration and soil water storage in long series of rainfall-runoff process

Biologia ◽  
2009 ◽  
Vol 64 (3) ◽  
Author(s):  
Josef Buchtele ◽  
Miroslav Tesař
Keyword(s):  
Vegetation Cover ◽  
Dominant Role ◽  
Water Storage ◽  
Water Levels ◽  
Soil Water Storage ◽  
Time Variability ◽  
Rainfall Runoff ◽  
Groundwater Storage ◽  
Surface Water Storage

AbstractNatural variability, i. e. climatic oscillation, influences the development of vegetation in the annual cycle. At the same time it creates the conditions for the changes of the vegetation cover even in the scale of centuries. This is the phenomenon, which causes the variation or tendencies in evapotranspiration demands and consequently of water storage regime, and its long scale change is sometimes disregarded. The simulation of rainfall-runoff process has been used for the re-evaluation of the assumed evapotranspiration demand due to the developing vegetation cover and of groundwater storage in the catchments. The simulations provide the results, which illustrate the dominant role of transpiration in comparison with other components of evapotranspiration. The simulations also illustrate the interaction between evapotranspiration and groundwater storage. Additionally, the modelling confirms that it could be useful to compare the parameters for the recession process of simulated sub-surface water storage with the decreases of observed outflow of springs and/or with the course of water levels in the bore holes.

scholarly journals Investigating the role of antecedent SMAP satellite soil moisture, radar rainfall and MODIS vegetation on runoff production in an agricultural region

2019 ◽  
Author(s):  
Navid Jadidoleslam ◽  
Ricardo Mantilla ◽  
Witold F. Krajewski ◽  
Radoslaw Goska
Keyword(s):  
Soil Moisture ◽  
Agricultural Landscapes ◽  
Rainfall Runoff ◽  
Antecedent Soil Moisture ◽  
Radar Rainfall ◽  
Event Scale ◽  
Moisture Deficit ◽  
Runoff Production

Following results by Crow et al. (2017) [Geophys. Res. Lett. 44, 5495-5503] on the impact of antecedent soil moisture on runoff production, we investigate total runoff production during individual rainfall-runoff events in agricultural landscapes as a function of antecedent soil moisture, total rainfall, and vegetation cover for catchments with drainage areas ranging from 80-1000 km2 in the state of Iowa, USA. For our study, we use Enhanced SMAP soil moisture estimates, the MODIS enhanced vegetation index (EVI), gauge-corrected Stage IV radar rainfall, and USGS streamflow data. We analyze the event runoff ratio as a function of event-scale rainfall, antecedent SMAP soil moisture and soil-moisture-deficit-normalized rainfall for the events in a period from March 31, 2015 to October 31, 2018. Our goal is to confirm the relationships identified by Crow et al. (2017) in heavily managed agricultural landscapes and to refine some of their methodological steps to quantify the role of additional variables controlling runoff production. To this end, we define three different strategies to identify rainfall-runoff events and add a baseflow separation step to better insulate event scale stormflow runoff. We test the effects of antecedent soil moisture, rainfall, and vegetation on the event-scale runoff ratio. The antecedent SMAP soil moisture and event-scale rainfall are found to have significant predictive power in estimating event runoff ratio. Soil moisture deficit-normalized rainfall, introduced as the ratio of event-scale rainfall to available space in top soil before initiation of the event, exhibited a more distinct relationship with runoff ratio. The long-term analysis of runoff ratio, rainfall, and MODIS EVI indicated that, in an agricultural region, vegetation plays a significant role in determining event-scale runoff ratios. The methodology and outcome of our study have direct implications on real-time flood forecasting and long-term hydrologic assessments.

scholarly journals Role of climate forecasts and initial conditions in developing streamflow and soil moisture forecasts in a rainfall–runoff regime

2013 ◽  
Vol 17 (2) ◽  
pp. 721-733 ◽  
Author(s):  
T. Sinha ◽  
A. Sankarasubramanian
Keyword(s):  
Soil Moisture ◽  
Land Surface ◽  
Lead Time ◽  
Monthly Precipitation ◽  
Rainfall Runoff ◽  
Climate Forecasts ◽  
Monthly Streamflow ◽  
Streamflow Forecasts ◽  
Runoff Regime

Abstract. Skillful seasonal streamflow forecasts obtained from climate and land surface conditions could significantly improve water and energy management. Since climate forecasts are updated on a monthly basis, we evaluate the potential in developing operational monthly streamflow forecasts on a continuous basis throughout the year. Further, basins in the rainfall–runoff regime critically depend on the forecasted precipitation in the upcoming months as opposed to snowmelt regimes where initial hydrological conditions (IHC) play a critical role. The goal of this study is to quantify the role of updated monthly precipitation forecasts and IHC in forecasting 6-month lead monthly streamflow and soil moisture for a rainfall–runoff mechanism dominated basin – Apalachicola River at Chattahoochee, FL. The Variable Infiltration Capacity (VIC) land surface model is implemented with two forcings: (a) updated monthly precipitation forecasts from ECHAM4.5 Atmospheric General Circulation Model (AGCM) forced with sea surface temperature forecasts and (b) daily climatological ensembles. The difference in skill between the above two quantifies the improvements that could be attainable using the AGCM forecasts. Monthly retrospective streamflow forecasts are developed from 1981 to 2010 and streamflow forecasts estimated from the VIC model are also compared with those predicted by using the principal component regression (PCR) model. The mean square error (MSE) in predicting monthly streamflows, using the VIC model, are compared with the MSE of streamflow climatology under ENSO (El Niño Southern Oscilation) conditions as well as under normal years. Results indicate that VIC forecasts obtained using ECHAM4.5 are significantly better than VIC forecasts obtained using climatological ensembles and PCR models over 2–6 month lead time during winter and spring seasons in capturing streamflow variability and reduced mean square errors. However, at 1-month lead time, streamflow utilizing the climatological forcing scheme outperformed ECHAM4.5 based streamflow forecasts during winter and spring, indicating a dominant role of IHCs up to a 1-month lead time. During ENSO years, streamflow forecasts exhibit better skill even up to a six-month lead time. Comparisons of the seasonal soil moisture forecasts, developed using ECHAM4.5 forcings, with seasonal streamflows also show significant skill, up to a 6-month lead time, in the four seasons.

Soil Moisture Regime Changes in Tephra-Mulched Soils

2002 ◽  
Vol 66 (1) ◽  
pp. 202 ◽  
Author(s):  
M. Tejedor ◽  
C. C. Jiménez ◽  
F. Díaz
Keyword(s):  
Soil Moisture ◽  
Moisture Regime ◽  
Regime Changes ◽  
Soil Moisture Regime

scholarly journals Hillslope Contribution to the Clark Instantaneous Unit Hydrograph: Application to the Seolmacheon Basin, Korea

Water ◽  
2021 ◽  
Vol 13 (12) ◽  
pp. 1707
Author(s):  
Chulsang Yoo ◽  
Huy Phuong Doan ◽  
Changhyun Jun ◽  
Wooyoung Na
Keyword(s):  
Peak Flow ◽  
Peak Time ◽  
Rainfall Runoff ◽  
Maximum Rainfall ◽  
Rainfall Events ◽  
Storage Coefficient ◽  
Channel Velocity ◽  
Linear Reservoir ◽  
Mountainous Basin

In this study, the time–area curve of an ellipse is analytically derived by considering flow velocities within both channel and hillslope. The Clark IUH is also derived analytically by solving the continuity equation with the input of the derived time–area curve to the linear reservoir. The derived Clark IUH is then evaluated by application to the Seolmacheon basin, a small mountainous basin in Korea. The findings in this study are summarized as follows. (1) The time–area curve of a basin can more realistically be derived by considering both the channel and hillslope velocities. The role of the hillslope velocity can also be easily confirmed by analyzing the derived time–area curve. (2) The analytically derived Clark IUH shows the relative roles of the hillslope velocity and the storage coefficient. Under the condition that the channel velocity remains unchanged, the hillslope velocity controls the runoff peak flow and the concentration time. On the other hand, the effect of the storage coefficient can be found in the runoff peak flow and peak time, as well as in the falling limb of the runoff hydrograph. These findings are also confirmed in the analysis of rainfall–runoff events of the Seolmacheon basin. (3) The effect of the hillslope velocity varies considerably depending on the rainfall events, which is also found to be mostly dependent upon the maximum rainfall intensity.

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

Water ◽  
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.

The Ideological Dimensionality in the Middle Eastern and North African Constitutions: A New Era in the Evolution of Islamic Constitutionalism

2020 ◽  
pp. 147892992091294
Author(s):  
Berna Öney
Keyword(s):  
Middle Eastern ◽  
Political Regime ◽  
North African ◽  
New Era ◽  
Regime Changes ◽  
Political Debates ◽  
Before And After ◽  
Popular Movements ◽  
Ideological Dimension

The popular movements in 2011 led to many regime changes that resulted in amended or new constitutions in the Middle East and North Africa region. The constitutional debates concentrated mainly on the functions of the constitutions in authoritarian regimes, constitution-making processes, and the role of Islam during and after the uprisings. However, no research has analyzed the ideological dimensionality of the Middle Eastern and North African constitutions. By analyzing 19 newly enacted, drafted, and amended constitutions before and after the popular movements in the region, this article shows that the single ideological dimension in the constitutions can be defined by the openness of a state for liberal and modern values. This ideological dimension encompasses all the regional political debates on the political regime dynamics, the inclusion of rights and liberties, and the role of Islam. Besides offering an alternative typology for the constitutions in the region, this article also provides evidence for the beginning of the fourth phase of Islamic constitutionalism that merges the ideas of rule of law, which originates from democratic notions, and Islamic norms.

scholarly journals The Role of Averaging for Improving Sea Surface Salinity Retrieval from the Soil Moisture and Ocean Salinity (SMOS) Satellite and Impact of Auxiliary Data

2007 ◽  
Vol 24 (2) ◽  
pp. 255-269 ◽  
Author(s):  
Sabine Philipps ◽  
Christine Boone ◽  
Estelle Obligis
Keyword(s):  
Soil Moisture ◽  
Sensitivity Study ◽  
Sea Surface ◽  
Sea Surface Salinity ◽  
Global Ocean ◽  
Surface Salinity ◽  
Auxiliary Data ◽  
Additional Information ◽  
Ocean Salinity

Abstract Soil Moisture and Ocean Salinity (SMOS) was chosen as the European Space Agency’s second Earth Explorer Opportunity mission. One of the objectives is to retrieve sea surface salinity (SSS) from measured brightness temperatures (TBs) at L band with a precision of 0.2 practical salinity units (psu) with averages taken over 200 km by 200 km areas and 10 days [as suggested in the requirements of the Global Ocean Data Assimilation Experiment (GODAE)]. The retrieval is performed here by an inverse model and additional information of auxiliary SSS, sea surface temperature (SST), and wind speed (W). A sensitivity study is done to observe the influence of the TBs and auxiliary data on the SSS retrieval. The key role of TB and W accuracy on SSS retrieval is verified. Retrieval is then done over the Atlantic for two cases. In case A, auxiliary data are simulated from two model outputs by adding white noise. The more realistic case B uses independent databases for reference and auxiliary ocean parameters. For these cases, the RMS error of retrieved SSS on pixel scale is around 1 psu (1.2 for case B). Averaging over GODAE scales reduces the SSS error by a factor of 12 (4 for case B). The weaker error reduction in case B is most likely due to the correlation of errors in auxiliary data. This study shows that SSS retrieval will be very sensitive to errors on auxiliary data. Specific efforts should be devoted to improving the quality of auxiliary data.

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