Ghada Serafy - Academia.edu (original) (raw)

Papers by Ghada Serafy

Research paper thumbnail of Adapted/improved process-based models assimilating EO/ in situ data

This report details the proof of concept for enhancing modelling applications within Protected Ar... more This report details the proof of concept for enhancing modelling applications within Protected Areas (PAs) with in-situ and remotely sensed data products. It showcases the manner through which the various partners involved in the ECOPOTENTIAL project were able to incorporate remote sensed and in-situ data, within a modelling framework to enhance the outputs of their models, or in some cases, the data enabled the models to be run on more than theoretical inputs. The activities detailed within represent an advancement and application of the methodologies proposed and reviewed within the project to specific case-study sites representing the PAs of ECOPOTENTIAL as well as Pan-European investigations

Research paper thumbnail of Assessment of status and evolution of ecosystem service indicators

Ecosystem services indicators are important to measure the trends and state of ecosystem service ... more Ecosystem services indicators are important to measure the trends and state of ecosystem service delivery; with recent years seeing a wide indicator base being developed. Indicators are powerful tools to inform and improve the knowledge base on ecosystems and ecosystem services, which are useful for decision makers at any spatial scale for basing their decisions on evidence and also at a higher levels. A selection of Protected Areas (PAs) from mountain, coast and marine, and arid ecosystems were used as case study areas to investigate a selection of ecosystem indicators and how they can be used to monitor ecosystem services in PAs. In total twelve PAs participated in this report, five from mountain areas, two from arid/semi-arid areas and five from coastal/marine areas. The types of ecosystem service are concurrent with the CICES classification, but the selection of most relevant ecosystem service varies between different PAs. Where possibly, supply, demand and beneficiaries were defined for each of the ecosystem service

Research paper thumbnail of Input correction in rainfall runoff models using the Ensemble Kalman filter

Environmental Hydraulics and Sustainable Water Management, Two Volume Set, 2004

Research paper thumbnail of Application of Ensemble Kalman Filtering in Delft3D-Flow

Research paper thumbnail of Groundwater flow pattern identification using the adjoint method in a particle model for pollutant transport

In this paper, a groundwater flow pattern identification algorithm using contamination measuremen... more In this paper, a groundwater flow pattern identification algorithm using contamination measurements is developed for particle models modelling transport of pollutants in groundwater. The parameter estimation problem is formulated as an optimization problem and is solved with a gradient based algorithm. For each generated particle track, the adjoint track is determined. These adjoint tracks are used to efficiently compute the gradient of the objective function. The approach of estimating the velocity fields is discussed and is illustrated with hypothetical applications. Furthermore, the performance of the algorithm is tested with different number of particles and more parameters.

Research paper thumbnail of Verwerking van remote sensing data en gegevens van grootschalige modellen in lokaal toepasbare zee- en kustmodellen

Research paper thumbnail of Sequence manager description in COSTA interface terminology

Research paper thumbnail of Particle filtering and Ensemble Kalman Filtering for runoff nowcasting using conceptual rainfall runoff models

Sequential importance resampling (SIR) filter, residual resampling filter (RR), and an ensemble K... more Sequential importance resampling (SIR) filter, residual resampling filter (RR), and an ensemble Kalman (EnKF) filter that can handle dynamic nonlinear/non-Gaussian models are compared to correct erroneous model inputs and to obtain a rainfall-runoff update with a conceptual rainfall-runoff model HBV-96 for flood forecasting purposes. EnKF performs best with a low number of ensemble members. The RR filter performs best at intermediate and high number of particles, although differences are small. With all filters the rainfall error could be estimated during a synthetic experiment when the soil is not too dry and the measurement error on the discharge is not dominant. The temperature error could only be estimated when the temperature is close to 0°C. When applying these methods to a real case, good results are obtained. For low flows, EnKF outperforms both particle filters, because it is less sensitive to misspecification of the model and uncertainties. These methods are feasible and easy to implement in real flood forecasting systems. Further research on the assumptions on model uncertainties and measurement uncertainties is recommended.

Research paper thumbnail of Ten-years sediment dynamics in Northern Adriatic sea investigated through optical remote sensing observations

2015 IEEE International Geoscience and Remote Sensing Symposium (IGARSS), 2015

Understanding the factors influencing sediment fluxes is a key issue to interpret the evolution o... more Understanding the factors influencing sediment fluxes is a key issue to interpret the evolution of coastal sedimentation under natural and human impact and relevant for the natural resources management. Despite river plumes represent one of the major gain in sedimentary budget of littoral cells, complex behavior of coastal plumes, like river discharge characteristics, wind stress and hydro-climatic variables, has not been yet fully investigated. Use of Earth Observation data allows the identification of spatial and temporal variations of suspended sediments related to river runoff, seafloor erosion, sediment transport and deposition processes. The objective of this study is to investigate superficial processes in sedimentary depositional marine environment integrating in-situ data and remote sensing data. The developed innovative approach allow quantitative evaluation of sediment dynamics using Earth Observation data, by relating spatial and temporal patterns of sediment dispersal with climatic forcings.

Research paper thumbnail of Comparison of Ekf and Enkf in Sobek River: Case Study Maxau-Ijssel

(In 2 Volumes, with CD-ROM), 2004

Research paper thumbnail of Conversion of deterministic models into stochastic models: approach and three worked out examples as guidance for application of data assimilation

Research paper thumbnail of Coastal Biomass Observatory Services

Research paper thumbnail of The ensemble particle filter (EnPF) in rainfall-runoff models

Stochastic Environmental Research and Risk Assessment, 2009

Research paper thumbnail of Monitoring biodiversity change through effective global coordination

Current Opinion in Environmental Sustainability, 2017

The ability to monitor changes in biodiversity, and their societal impact, is critical to conserv... more The ability to monitor changes in biodiversity, and their societal impact, is critical to conserving species and managing ecosystems. While emerging technologies increase the breadth and reach of data acquisition, monitoring efforts are still spatially and temporally fragmented, and taxonomically biased. Appropriate long-term information remains therefore limited. The Group on Earth Observations Biodiversity Observation Network (GEO BON) aims to provide a general framework for biodiversity monitoring to support decision makers. Here, we discuss the coordinated observing system adopted by GEO BON, and review challenges and advances in its implementation, focusing on two interconnected core components-the Essential Biodiversity Variables as a standard framework for biodiversity monitoring, and the Biodiversity Observation Networks that support harmonized observation systems-while highlighting their societal relevance.

Research paper thumbnail of Quantification of Benthic Phytoplankton using Remote Sensing and Machine Learning in the Wadden Sea *

One of the main indicators of ecosystem stability in coastal regions is the occurrence and distri... more One of the main indicators of ecosystem stability in coastal regions is the occurrence and distribution of primary producers. In the intertidal flats of the Wadden Sea, benthic phytoplankton such as microphytobenthos are significant primary providers of energy. However, the Wadden Sea monitoring data inventory states that there is low availability of microphytobenthos data despite its high demand. To address this gap, a remote sensing approach coupled with data fusion through machine learning using the Random Forest algorithm was adopted and developed. This study also maximized existing datasets to demonstrate other possible applications of such data and subsequently, the added practical value these datasets offer.

Research paper thumbnail of A stochastic weather generator to enrich existing climate change scenarios and quantify uncertainties in marine and coastal ecosystems

EGU General Assembly Conference Abstracts, Apr 1, 2019

Research paper thumbnail of The GEO AquaWatch Initiative

Research paper thumbnail of A Bird's‐Eye View of Monitoring and Management of Marine and Coastal Protected Areas

Earth Observation Applications and Global Policy Frameworks

Research paper thumbnail of HiSea - High resolution Copernicus-based information services at sea for ports and aquaculture*

EGU General Assembly Conference Abstracts, Apr 1, 2019

Research paper thumbnail of Operational modelling capacity in European Seas : An assessment and recommendations for improvement

An overview of the current European capacity in terms of operational modeling of marine and coast... more An overview of the current European capacity in terms of operational modeling of marine and coastal systems is presented. This overview is compiled from a survey conducted in 2018–2019 among members of EuroGOOS and its related network of Regional Operational Oceanographic Systems, addressing the purposes, context, and technical specificities of operational modeling systems. Contributions to the survey were received from 49 organizations around Europe, which represent 104 operational model systems simulating mostly hydrodynamics, biogeochemistry, and sea waves. The analysis of contributions highlights the strengths and weaknesses of the current capacity from an operational point of view and leads to the formulation of recommendations toward the improvement of marine operational modeling services in Europe. In particular, this study highlights the heterogeneity of the European operational modeling capacity in terms of atmospheric and land boundary conditions, its limited deployment fo...

Research paper thumbnail of Adapted/improved process-based models assimilating EO/ in situ data

This report details the proof of concept for enhancing modelling applications within Protected Ar... more This report details the proof of concept for enhancing modelling applications within Protected Areas (PAs) with in-situ and remotely sensed data products. It showcases the manner through which the various partners involved in the ECOPOTENTIAL project were able to incorporate remote sensed and in-situ data, within a modelling framework to enhance the outputs of their models, or in some cases, the data enabled the models to be run on more than theoretical inputs. The activities detailed within represent an advancement and application of the methodologies proposed and reviewed within the project to specific case-study sites representing the PAs of ECOPOTENTIAL as well as Pan-European investigations

Research paper thumbnail of Assessment of status and evolution of ecosystem service indicators

Ecosystem services indicators are important to measure the trends and state of ecosystem service ... more Ecosystem services indicators are important to measure the trends and state of ecosystem service delivery; with recent years seeing a wide indicator base being developed. Indicators are powerful tools to inform and improve the knowledge base on ecosystems and ecosystem services, which are useful for decision makers at any spatial scale for basing their decisions on evidence and also at a higher levels. A selection of Protected Areas (PAs) from mountain, coast and marine, and arid ecosystems were used as case study areas to investigate a selection of ecosystem indicators and how they can be used to monitor ecosystem services in PAs. In total twelve PAs participated in this report, five from mountain areas, two from arid/semi-arid areas and five from coastal/marine areas. The types of ecosystem service are concurrent with the CICES classification, but the selection of most relevant ecosystem service varies between different PAs. Where possibly, supply, demand and beneficiaries were defined for each of the ecosystem service

Research paper thumbnail of Input correction in rainfall runoff models using the Ensemble Kalman filter

Environmental Hydraulics and Sustainable Water Management, Two Volume Set, 2004

Research paper thumbnail of Application of Ensemble Kalman Filtering in Delft3D-Flow

Research paper thumbnail of Groundwater flow pattern identification using the adjoint method in a particle model for pollutant transport

In this paper, a groundwater flow pattern identification algorithm using contamination measuremen... more In this paper, a groundwater flow pattern identification algorithm using contamination measurements is developed for particle models modelling transport of pollutants in groundwater. The parameter estimation problem is formulated as an optimization problem and is solved with a gradient based algorithm. For each generated particle track, the adjoint track is determined. These adjoint tracks are used to efficiently compute the gradient of the objective function. The approach of estimating the velocity fields is discussed and is illustrated with hypothetical applications. Furthermore, the performance of the algorithm is tested with different number of particles and more parameters.

Research paper thumbnail of Verwerking van remote sensing data en gegevens van grootschalige modellen in lokaal toepasbare zee- en kustmodellen

Research paper thumbnail of Sequence manager description in COSTA interface terminology

Research paper thumbnail of Particle filtering and Ensemble Kalman Filtering for runoff nowcasting using conceptual rainfall runoff models

Sequential importance resampling (SIR) filter, residual resampling filter (RR), and an ensemble K... more Sequential importance resampling (SIR) filter, residual resampling filter (RR), and an ensemble Kalman (EnKF) filter that can handle dynamic nonlinear/non-Gaussian models are compared to correct erroneous model inputs and to obtain a rainfall-runoff update with a conceptual rainfall-runoff model HBV-96 for flood forecasting purposes. EnKF performs best with a low number of ensemble members. The RR filter performs best at intermediate and high number of particles, although differences are small. With all filters the rainfall error could be estimated during a synthetic experiment when the soil is not too dry and the measurement error on the discharge is not dominant. The temperature error could only be estimated when the temperature is close to 0°C. When applying these methods to a real case, good results are obtained. For low flows, EnKF outperforms both particle filters, because it is less sensitive to misspecification of the model and uncertainties. These methods are feasible and easy to implement in real flood forecasting systems. Further research on the assumptions on model uncertainties and measurement uncertainties is recommended.

Research paper thumbnail of Ten-years sediment dynamics in Northern Adriatic sea investigated through optical remote sensing observations

2015 IEEE International Geoscience and Remote Sensing Symposium (IGARSS), 2015

Understanding the factors influencing sediment fluxes is a key issue to interpret the evolution o... more Understanding the factors influencing sediment fluxes is a key issue to interpret the evolution of coastal sedimentation under natural and human impact and relevant for the natural resources management. Despite river plumes represent one of the major gain in sedimentary budget of littoral cells, complex behavior of coastal plumes, like river discharge characteristics, wind stress and hydro-climatic variables, has not been yet fully investigated. Use of Earth Observation data allows the identification of spatial and temporal variations of suspended sediments related to river runoff, seafloor erosion, sediment transport and deposition processes. The objective of this study is to investigate superficial processes in sedimentary depositional marine environment integrating in-situ data and remote sensing data. The developed innovative approach allow quantitative evaluation of sediment dynamics using Earth Observation data, by relating spatial and temporal patterns of sediment dispersal with climatic forcings.

Research paper thumbnail of Comparison of Ekf and Enkf in Sobek River: Case Study Maxau-Ijssel

(In 2 Volumes, with CD-ROM), 2004

Research paper thumbnail of Conversion of deterministic models into stochastic models: approach and three worked out examples as guidance for application of data assimilation

Research paper thumbnail of Coastal Biomass Observatory Services

Research paper thumbnail of The ensemble particle filter (EnPF) in rainfall-runoff models

Stochastic Environmental Research and Risk Assessment, 2009

Research paper thumbnail of Monitoring biodiversity change through effective global coordination

Current Opinion in Environmental Sustainability, 2017

The ability to monitor changes in biodiversity, and their societal impact, is critical to conserv... more The ability to monitor changes in biodiversity, and their societal impact, is critical to conserving species and managing ecosystems. While emerging technologies increase the breadth and reach of data acquisition, monitoring efforts are still spatially and temporally fragmented, and taxonomically biased. Appropriate long-term information remains therefore limited. The Group on Earth Observations Biodiversity Observation Network (GEO BON) aims to provide a general framework for biodiversity monitoring to support decision makers. Here, we discuss the coordinated observing system adopted by GEO BON, and review challenges and advances in its implementation, focusing on two interconnected core components-the Essential Biodiversity Variables as a standard framework for biodiversity monitoring, and the Biodiversity Observation Networks that support harmonized observation systems-while highlighting their societal relevance.

Research paper thumbnail of Quantification of Benthic Phytoplankton using Remote Sensing and Machine Learning in the Wadden Sea *

One of the main indicators of ecosystem stability in coastal regions is the occurrence and distri... more One of the main indicators of ecosystem stability in coastal regions is the occurrence and distribution of primary producers. In the intertidal flats of the Wadden Sea, benthic phytoplankton such as microphytobenthos are significant primary providers of energy. However, the Wadden Sea monitoring data inventory states that there is low availability of microphytobenthos data despite its high demand. To address this gap, a remote sensing approach coupled with data fusion through machine learning using the Random Forest algorithm was adopted and developed. This study also maximized existing datasets to demonstrate other possible applications of such data and subsequently, the added practical value these datasets offer.

Research paper thumbnail of A stochastic weather generator to enrich existing climate change scenarios and quantify uncertainties in marine and coastal ecosystems

EGU General Assembly Conference Abstracts, Apr 1, 2019

Research paper thumbnail of The GEO AquaWatch Initiative

Research paper thumbnail of A Bird's‐Eye View of Monitoring and Management of Marine and Coastal Protected Areas

Earth Observation Applications and Global Policy Frameworks

Research paper thumbnail of HiSea - High resolution Copernicus-based information services at sea for ports and aquaculture*

EGU General Assembly Conference Abstracts, Apr 1, 2019

Research paper thumbnail of Operational modelling capacity in European Seas : An assessment and recommendations for improvement

An overview of the current European capacity in terms of operational modeling of marine and coast... more An overview of the current European capacity in terms of operational modeling of marine and coastal systems is presented. This overview is compiled from a survey conducted in 2018–2019 among members of EuroGOOS and its related network of Regional Operational Oceanographic Systems, addressing the purposes, context, and technical specificities of operational modeling systems. Contributions to the survey were received from 49 organizations around Europe, which represent 104 operational model systems simulating mostly hydrodynamics, biogeochemistry, and sea waves. The analysis of contributions highlights the strengths and weaknesses of the current capacity from an operational point of view and leads to the formulation of recommendations toward the improvement of marine operational modeling services in Europe. In particular, this study highlights the heterogeneity of the European operational modeling capacity in terms of atmospheric and land boundary conditions, its limited deployment fo...