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Yang Hong - One of the best experts on this subject based on the ideXlab platform.
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microwave satellite data for hydrologic modeling in ungauged basins
IEEE Geoscience and Remote Sensing Letters, 2012Co-Authors: Sadiq Ibrahim Khan, Yang Hong, Humberto Vergara, Jonathan J Gourley, G R Brakenridge, T De Groeve, Zachary L Flamig, Fritz Policelli, Bin YongAbstract:An innovative Flood-Prediction framework is developed using Tropical Rainfall Measuring Mission precipitation forcing and a proxy for river discharge from the Advanced Microwave Scanning Radiometer for Earth Observing System (AMSR-E) onboard the National Aeronautics and Space Administration's Aqua satellite. The AMSR-E-detected water surface signal was correlated with in situ measurements of streamflow in the Okavango Basin in Southern Africa as indicated by a Pearson correlation coefficient of 0.90. A distributed hydrologic model, with structural data sets derived from remote-sensing data, was calibrated to yield simulations matching the Flood frequencies from the AMSR-E-detected water surface signal. Model performance during a validation period yielded a Nash-Sutcliffe efficiency of 0.84. We concluded that remote-sensing data from microwave sensors could be used to supplement stream gauges in large sparsely gauged or ungauged basins to calibrate hydrologic models. Given the global availability of all required data sets, this approach can be potentially expanded to improve Flood monitoring and Prediction in sparsely gauged basins throughout the world.
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evaluation of the real time trmm based multi satellite precipitation analysis for an operational Flood Prediction system in nzoia basin lake victoria africa
Natural Hazards, 2009Co-Authors: Li Li, Yang Hong, Jiahu Wang, Robert F Adler, Frederick Policelli, Shahid Habib, Daniel Irwn, Tesfaye Korme, Lawrence OkelloAbstract:Many researchers seek to take advantage of the recently available and virtually uninterrupted supply of satellite-based rainfall information as an alternative and supplement to the ground-based observations in order to implement a cost-effective Flood Prediction in many under-gauged regions around the world. Recently, NASA Applied Science Program has partnered with USAID and African-RCMRD to implement an operational water-hazard warning system, SERVIR-Africa. The ultimate goal of the project is to build up disaster management capacity in East Africa by providing local governmental officials and international aid organizations a practical decision-support tool in order to better assess emerging Flood impacts and to quantify spatial extent of Flood risk, as well as to respond to such Flood emergencies more expediently. The objective of this article is to evaluate the applicability of integrating NASA’s standard satellite precipitation product with a Flood Prediction model for disaster management in Nzoia, sub-basin of Lake Victoria, Africa. This research first evaluated the TMPA real-time rainfall data against gauged rainfall data from the year 2002 through 2006. Then, the gridded Xinanjiang Model was calibrated to Nzoia basin for period of 1985–2006. Benchmark streamflow simulations were produced with the calibrated hydrological model using the rain gauge and observed streamflow data. Afterward, continuous discharge Predictions forced by TMPA 3B42RT real-time data from 2002 through 2006 were simulated, and acceptable results were obtained in comparison with the benchmark performance according to the designated statistic indices such as bias ratio (20%) and NSCE (0.67). Moreover, it is identified that the Flood Prediction results were improved with systematically bias-corrected TMPA rainfall data with less bias (3.6%) and higher NSCE (0.71). Although the results justify to suggest to us that TMPA real-time data can be acceptably used to drive hydrological models for Flood Prediction purpose in Nzoia basin, continuous progress in space-borne rainfall estimation technology toward higher accuracy and higher spatial resolution is highly appreciated. Finally, it is also highly recommended that to increase Flood forecasting lead time, more reliable and more accurate short- or medium-range quantitative precipitation forecasts is a must. Copyright Springer Science+Business Media B.V. 2009
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evaluation of the real time trmm based multi satellite precipitation analysis for an operational Flood Prediction system in nzoia basin lake victoria africa
Natural Hazards, 2009Co-Authors: Yang Hong, Jiahu Wang, Robert F Adler, Frederick Policelli, Shahid Habib, Daniel Irwn, Tesfaye Korme, Lawrence OkelloAbstract:Many researchers seek to take advantage of the recently available and virtually uninterrupted supply of satellite-based rainfall information as an alternative and supple- ment to the ground-based observations in order to implement a cost-effective Flood Prediction in many under-gauged regions around the world. Recently, NASA Applied Science Program has partnered with USAID and African-RCMRD to implement an operational water-hazard warning system, SERVIR-Africa. The ultimate goal of the project is to build up disaster management capacity in East Africa by providing local governmental officials and international aid organizations a practical decision-support tool in order to better assess emerging Flood impacts and to quantify spatial extent of Flood risk, as well as to respond to such Flood emergencies more expediently. The objective of this article is to evaluate the applicability of integrating NASA's standard satellite precipitation product with a Flood Prediction model for disaster management in Nzoia, sub-basin of Lake Vic- toria, Africa. This research first evaluated the TMPA real-time rainfall data against gauged rainfall data from the year 2002 through 2006. Then, the gridded Xinanjiang Model was calibrated to Nzoia basin for period of 1985-2006. Benchmark streamflow simulations were produced with the calibrated hydrological model using the rain gauge and observed
Pulat, Hasan Fırat - One of the best experts on this subject based on the ideXlab platform.
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Filyos nehri seddeleri tasarımı için uygun taşkın tahmini yöntemi seçilerek birim hidrografın elde edilmesi
YOUNG SCHOLARS UNION, 2020Co-Authors: Semerci Aykut, Tayfur Gökmen, Pulat, Hasan FıratAbstract:Purpose Due to the fact that there are airports, settlements and agricultural areas close to the Filyos Flood basin, it is the construction of Filyos levees by obtaining the unit hydrograph by selecting the appropriate Flood Prediction method. Design/methodology/approach Floods are one of the most complex and important problems of engineering hydrology. This is a common problem in many countries, including Turkey. Floods create a risk for urban areas, infrastructure, industrial structures and agriculture. Levees are built along the riverbanks including in Turkey to mitigate the effects of Flooding due to the overflowing of rivers all over the world and Filyos levees are one of them. The fact that it is close to the airport, residential areas and agricultural areas to the Flood area has been important for the construction of the Filyos levees. Precipitation is very high in the Flood area downstream of this basin. Several hydrological studies are carried out to identify Floods. The hydrograph shows the change in flow rate over time in a stream section. Unit hydrograph is the hydrograph of the direct flow of residual precipitation at a unit height (1 cm) of constant intensity falling into the basin for a certain period of time. Statistical, Rational, Mockus and Synder methods are widely used for Flood Prediction. Each method has some important limited conditions and these methods give different results for the same site. The maximum Flood flow rate was calculated for the maximum Flood where any building can remain safe. Deterministic and statistical methods are used for Flood flow. In this study, the unit hydrograph method (deterministic) is used. Since the basin area is larger than 1000 km2, Snyder method can use. Findings Snyder method was selected according to the meteorological, hydrological and topographic conditions of the Filyos Basin and a unit hydrograph was formed. In the calculation of Flood peaks of the Filyos river exit basin, which should be repeated 100 years using synthetic methods; precipitation hydrograph peak flows were found to be 2120 (m3/sec) and peak flow was approximately 31 hours. It was resumed approximately 144 hours after the peak flow. Originality/value Flood (peak) flow and unit hydrograph graphic created according to Snyder method can be taken as basis in the design of Flood protection structures to be created in possible Floods in the basin. In addition, a good risk and economic analysis should be carried out as Floods will cause loss of life and property. Regular and continuous measurements should continue, as the risk of Flooding is high due to the rainy season in this basin. Keywords: Flood, Levee, Unit Hydrograph, Deterministic and Statistical Metho
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Filyos nehri seddeleri tasarımı için uygun taşkın tahmini yöntemi seçilerek birim hidrografın elde edilmesi
Young Scholars Union, 2020Co-Authors: Semerci Aykut, Tayfur Gökmen, Pulat, Hasan FıratAbstract:Purpose Due to the fact that there are airports, settlements and agricultural areas close to the Filyos Flood basin, it is the construction of Filyos levees by obtaining the unit hydrograph by selecting the appropriate Flood Prediction method. Design / Methodology / Approach Floods are one of the most complex and important problems of engineering hydrology. This is a common problem in many countries, including Turkey. Floods create a risk for urban areas, infrastructure, industrial structures and agriculture. Levees are built along the riverbanks including in Turkey to mitigate the effects of Flooding due to the overflowing of rivers all over the world and Filyos levees are one of them. The fact that it is close to the airport, residential areas and agricultural areas to the Flood area has been important for the construction of the Filyos levees. Precipitation is very high in the Flood area downstream of this basin. Several hydrological studies are carried out to identify Floods. The hydrograph shows the change in flow rate over time in a stream section. Unit hydrograph is the hydrograph of the direct flow of residual precipitation at a unit height (1 cm) of constant intensity falling into the basin for a certain period of time. Statistical, Rational, Mockus and Synder methods are widely used for Flood Prediction. Each method has some important limited conditions and these methods give different results for the same site. The maximum Flood flow rate was calculated for the maximum Flood where any building can remain safe. Deterministic and statistical methods are used for Flood flow. In this study, the unit hydrograph method (deterministic) is used. Since the basin area is larger than 1000 km2 , Snyder method can use.Findings Snyder method was selected according to the meteorological, hydrological and topographic conditions of the Filyos Basin and a unit hydrograph was formed. In the calculation of Flood peaks of the Filyos river exit basin, which should be repeated 100 years using synthetic methods; precipitation hydrograph peak flows were found to be 2120 (m3 /sec) and peak flow was approximately 31 hours. It was resumed approximately 144 hours after the peak flow.Originality/value Flood (peak) flow and unit hydrograph graphic created according to Snyder method can be taken as basis in the design of Flood protection structures to be created in possible Floods in the basin. In addition, a good risk and economic analysis should be carried out as Floods will cause loss of life and property. Regular and continuous measurements should continue, as the risk of Flooding is high due to the rainy season in this basin
Greg Easson - One of the best experts on this subject based on the ideXlab platform.
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satellite based Flood modeling using trmm based rainfall products
Sensors, 2007Co-Authors: Amanda Harris, Faisal Hossain, Sayma Rahman, Lance Yarborough, Amvrossios C Bagtzoglou, Greg EassonAbstract:Increasingly available and a virtually uninterrupted supply of satellite-estimatedrainfall data is gradually becoming a cost-effective source of input for Flood Predictionunder a variety of circumstances. However, most real-time and quasi-global satelliterainfall products are currently available at spatial scales ranging from 0.25o to 0.50o andhence, are considered somewhat coarse for dynamic hydrologic modeling of basin-scaleFlood events. This study assesses the question: what are the hydrologic implications ofuncertainty of satellite rainfall data at the coarse scale? We investigated this question onthe 970 km² Upper Cumberland river basin of Kentucky. The satellite rainfall productassessed was NASA's Tropical Rainfall Measuring Mission (TRMM) Multi-satellitePrecipitation Analysis (TMPA) product called 3B41RT that is available in pseudo real timewith a latency of 6-10 hours. We observed that bias adjustment of satellite rainfall data canimprove application in Flood Prediction to some extent with the trade-off of more falsealarms in peak flow. However, a more rational and regime-based adjustment procedureneeds to be identified before the use of satellite data can be institutionalized among Floodmodelers.
Faisal Hossain - One of the best experts on this subject based on the ideXlab platform.
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satellite based Flood modeling using trmm based rainfall products
Sensors, 2007Co-Authors: Amanda Harris, Faisal Hossain, Sayma Rahman, Lance Yarborough, Amvrossios C Bagtzoglou, Greg EassonAbstract:Increasingly available and a virtually uninterrupted supply of satellite-estimatedrainfall data is gradually becoming a cost-effective source of input for Flood Predictionunder a variety of circumstances. However, most real-time and quasi-global satelliterainfall products are currently available at spatial scales ranging from 0.25o to 0.50o andhence, are considered somewhat coarse for dynamic hydrologic modeling of basin-scaleFlood events. This study assesses the question: what are the hydrologic implications ofuncertainty of satellite rainfall data at the coarse scale? We investigated this question onthe 970 km² Upper Cumberland river basin of Kentucky. The satellite rainfall productassessed was NASA's Tropical Rainfall Measuring Mission (TRMM) Multi-satellitePrecipitation Analysis (TMPA) product called 3B41RT that is available in pseudo real timewith a latency of 6-10 hours. We observed that bias adjustment of satellite rainfall data canimprove application in Flood Prediction to some extent with the trade-off of more falsealarms in peak flow. However, a more rational and regime-based adjustment procedureneeds to be identified before the use of satellite data can be institutionalized among Floodmodelers.
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Flood Prediction in the future recognizing hydrologic issues in anticipation of the global precipitation measurement mission
Water Resources Research, 2006Co-Authors: Faisal Hossain, Dennis P LettenmaierAbstract:[1] The planned Global Precipitation Measurement (GPM) mission beckons hydrologists as an opportunity to improve Flood Prediction capability for medium to large river basins, especially in the underdeveloped world where in situ precipitation gauge networks are sparse. However, before the potential of GPM can be realized, there are a number of hydrologic issues that must be addressed. In particular, we argue that unless there is a shift in paradigm, the conventional assessment frameworks and metrics for estimation of precipitation from satellite sensors will remain inadequate for hydrologic purposes such as Flood Prediction. We also argue that greater emphasis must be placed on development of hydrologically relevant precipitation estimation algorithms and that this will require involvement of a broader cross section of the hydrologic community.
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assessment of current passive microwave and infrared based satellite rainfall remote sensing for Flood Prediction
Journal of Geophysical Research, 2004Co-Authors: Faisal Hossain, Emmanouil N AnagnostouAbstract:[1] The adequacy of current passive-microwave-(PM)- and infrared-(IR)-based satellite rainfall retrieval and sampling for Flood Prediction of a medium-sized watershed is investigated. On the basis of Tropical Rainfall Measuring Mission (TRMM) Precipitation Radar rainfall measurements, rain retrieval error parameters for PM and IR sensors are derived. PM rain retrievals are inferred from the overland component of the TRMM Microwave Imager (TMI) rain estimation algorithm, while IR retrievals are obtained from hourly PM-calibrated IR rain fields, which are part of a variable rainfall product (VAR) array produced at NASA/GSFC. A probabilistic error model is developed for satellite-based precipitation measurements on the basis of retrieval error parameters in this simulation study. The PM rain detection ability was found to be significantly more sensitive than that of IR while the successful no-rain detection probabilities were found to be 93% and 88%, respectively. The IR retrieval was found to give false alarm rain rates about twice as large as that of PM. The PM sensor constellation comprised two Special Sensor Microwave Imagers (SSM/I) (F14 and F15), the TMI, and the Advanced Microwave Sensing Radiometer (AMSR-E). It was found that current PM sampling is associated with Flood Prediction uncertainty approximately 50–100% higher than that of a canonical 3-hourly sampling planned for the Global Precipitation Measurement (GPM) mission. The comparatively greater limitation in capturing the correct space-time rain structure by IR retrievals had the effect of increasing the error in predicting the time of peak runoff when merging was performed with PM retrievals. It was found that a reduced standard error ( 0.90) can make IR retrievals useful in reducing uncertainty in the Prediction of peak runoff. To reduce the error in time to peak, further improvement, such as reduction in the IR retrieval's false alarm rates coupled with an even higher POD, may be necessary. In terms of overall runoff volume, combined moderate improvements in POD and error variance of current IR retrieval algorithms are sufficient for the reduction of Prediction uncertainty.
Luca Ferraris - One of the best experts on this subject based on the ideXlab platform.
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impact based flash Flood forecasting system sensitivity to high resolution numerical weather Prediction systems and soil moisture
Journal of Hydrology, 2019Co-Authors: Francesco Silvestro, Lauro Rossi, Lorenzo Campo, Antonio Parodi, Elisabetta Fiori, Roberto Rudari, Luca FerrarisAbstract:Abstract In recent years, continuous improvements have been made in weather forecasting and Flood Prediction with great benefit from Early Warning Systems (EWSs). Despite the continuous quest for innovation from the scientific and user communities, EWSs remain based mostly on hazard forecast, and the information on possible consequences and potential impacts is generally missing. In this work, a methodology for quantitative real-time impact assessment for flash Floods is presented. The methodology uses a multi-model ensemble approach and considers soil moisture uncertainty. Moreover, the Flood forecasting chain, which normally provides only the discharge probability of exceeding a given threshold, is extended to include a fully 2D hydraulic model and a damage estimation model to quantitatively assess impacts in terms of economic losses and the people involved. The procedure was tested on recent Flood events occurring in Genoa in northwestern Italy. This paper discusses the potential challenges and opportunities offered by this approach in the decision-making workflow in an operational context.