M. Suhyb Salama

University of Twente | UT · Department of Water Resources (WRS)

Remote sensing technologies have the potential to support monitoring of floating plastic litter in aquatic environments. An experimental campaign was carried out in a large-scale hydrodynamic test facility to explore the detectability of floating plastics in ocean waves, comparing and contrasting different microwave and optical remote sensing techn...

Smartphones, although not empowered as water quality sensing devices, can be used to obtain spectral information about our water quality through their enhanced capability to capture images and process using applications (APPs) developed to work within given colour spaces. As the focus of this study, models were developed through two colour spaces u...

Water quality monitoring and mapping is crucial for protecting ecosystems and human health, and it has become increasingly significant as societies worldwide prioritize environmental awareness and sustainable practices. This study focuses on advancing water quality monitoring by evaluating the performance of two smartphone applications (APPs) (Hydr...

Artisanal small-scale mines (ASMs) in the Amazon Rainforest are an important cause of deforestation, forest degradation, biodiversity loss, sedimentation in rivers, and mercury emissions. Satellite image data are widely used in environmental decision-making to monitor changes in the land surface, but ASMs are difficult to map from space. ASMs are s...

The remote sensing of turbidity and suspended particulate matter (SPM) relies on atmospheric corrections and bio-optical algorithms, but there is no one method that has better accuracy than the others for all satellites, bands, study areas, and purposes. Here, we evaluated different combinations of satellites (Landsat-8, Sentinel-2, and Sentinel-3)...

Water quality monitoring, essential for safeguarding ecosystems and human health, has gained increasing significance as societies worldwide prioritize environmental awareness and sustainable practices. Therefore, this study evaluates the performance of two smartphone applications (APPs), HydroColor and Citclops (now EyeOnWater), in estimating water...

Turbid coastal plumes carry sediments, nutrients, and pollutants. Satellite remote sensing is an effective tool for studying water quality parameters in these turbid plumes while covering a wide range of hydrological and meteorological conditions. However, determining boundaries of turbid coastal plumes poses a challenge. Traditionally, thresholds...

Spread across Twente and its neighbouring regions in the east of the Netherlands, a network of 20 profile soil moisture and temperature (5, 10, 20, 40, and 80 cm depths) monitoring stations was established in 2009. Field campaigns have been conducted covering the growing seasons of 2009, 2015, 2016, and 2017, during which soil sampling rings and ha...

One of the major sources of pollution affecting inland and coastal waters is related to poorly treated or untreated wastewater discharge, particularly in urbanized watersheds. The excess of nutrients, organic matter, and pathogens causes an overall deterioration of water quality and impairs valuable ecosystem services. The detection of wastewater p...

Suspended Particulate Matter (SPM) plays an important role in controlling water quality, particularly in turbid estuaries. SPM may be impacted by changes in weather and climate, including potential changes in the frequency or intensity of extremes. Yet, the linkages between extreme events in wind and river discharge, and particularly the role these...

In 2020, I embarked on another education project under the faculty initiative Stimulating Teacher Evaluation and Professionalization (STEP). Each year, I would dedicate approximately 20 hours to research and experimentation in teaching, focusing on collaborative learning . This research led to the development of the "Thru Climate Change" course (2E...

It is common in estuarine waters to place fixed monitoring stations, with the advantages of easy maintenance and continuous measurements. These two features make fixed monitoring stations indispensable for understanding the optical complexity of estuarine waters and enable an improved quantification of uncertainties in satellite-derived water quali...

We developed three playful games to support educational activities of the Climate Change Initiative programme and contribute to the international efforts to increase the awareness of the general public on climate change These games address the main triangle of the Climate Change Initiative on observation-environment-life: Monitoring the Environmen...

Water in coastal and estuary areas needs to be investigated as human activities is allegedly decrease their quality. This has led to optical remote sensing for mapping optical water quality using empirical and semi-analytical approaches. Therefore, this study aims to estimate the Total Suspended Matter (TSM) concentration from Medium Resolution Ima...

Outreach to STEM education

The primary aim of the Tertiary Training Materials (TTM) is to disseminate knowledge on climate change and satellite data records from the Climate Change Initiative (CCI) program through specialized modules. This report outlines the objectives, learning outcomes, structure, and content with references to the documentations. All materials are found...

In this report we provide a self-reflection on the past five years of the Master’s Programme in Geo-information Science and Earth Observation (MGEO). The report starts with a summary of the improvements made after the previous visitation. Next, we present and reflect on the aims of the MGEO education programme, what has been done to realise these a...

This report reflects on the internationalisation of MGEO and how it has progressed since 2014. In these past five years, we have upgraded the internationalisation of the programme and revised the curriculum. Most significantly, in 2018 we changed MGEO from an 18-month programme into a 2-year programme. Although the programme had already achieved th...

A R T I C L E I N F O Keywords: Long-term water quality monitoring Remote sensing Integration Multi-sensor satellites In-situ measurements Hyperspectral observations MERIS MSI OLCI ENVISAT Sentinel-2 Sentinel-3 2SeaColor MODTRAN Radiative Transfer modeling Coastal waters The Wadden Sea A B S T R A C T Recently, there have been significant efforts i...

Many coastal waters include large areas of Optically Shallow Waters (OSWs) ‎where the sea-bottom affects above-water observations of remote sensing ‎reflectance (Rrs [sr−1]). If not treated, the effect of bottom reflectance will ‎interfere with the correct retrieval of Water Constituent Concentrations ‎‎(WCCs) from hyperspectral and multispectral r...

This report provides a comprehensive analysis of Earth Observation (EO) related topics and maps them to Essential Climate Variables (ECVs). The analysis is performed on the STEM curricula in primary and secondary educations of eight European countries. In addition, the report provides descriptions of education prospectuses that will form the founda...

My work on entrepreneurship in geospatial education was undertaken to obtain the Senior University Teacher Qualification (SUTQ). In this work, I analyzed a vast array of surveys spanning a six-year period, examining feedback from 883 students. Based on this analysis and a literature review, I designed a course that addressed students' needs for ski...

he seasonal variability of sea surface salinity anomalies (SSSAs) in the Indian Ocean is investigated for its role in the South Asian Summer Monsoon. We have observed an elongated spatial-feature of the positive SSSAs in the southwestern Indian Ocean before the onset of the South Asian Summer Monsoon (SASM) by using both the Aquarius satellite and...

In this study, the effect of tide on the variation of concentrations of Chlorophyll-a (Chla) and Suspended Particulate Matters (SPM), retrieved from a complete dataset of diurnal close-range hyperspectral observations recorded at the NIOZ jetty station (NJS) located at the Marsdiep inlet in the Dutch part of the Wadden Sea, was evaluated. The two-s...

This document describes the training package developed for the Water Resource Management (WRM) component of the European Space Agency (ESA) initiative ‘Earth Observation for Sustainable Development (EO4SD)’ which aims at increasing the uptake of EO-based information in regular development operations at the national and international level. The EO4...

This is the original version of 2SeaColor with test data as published in Salama and Verhoef (2015, Remote Sensing of Environment 157, 111–122) https://github.com/suhybsalama/2SeaColor/releases

The study is mainly intended to assess and evaluate the water budget in the eastern basin at 1 km resolution, through a comprehensive model of the eastern aquifer by estimating the evapotranspiration (evaporation and transpiration), surface runoff and groundwater recharge in the targeted aquifer for the period (1950-2000). A spatial modelling appro...

The study is mainly intended to assess and evaluate the water budget in the eastern basin at 1 km resolution, through a comprehensive model of the eastern aquifer by estimating the evapotranspiration (evaporation and transpiration), surface runoff and groundwater recharge in the targeted aquifer for the period (1950-2000). A spatial modelling appro...

An accurate estimation of the chlorophyll-a (Chla) concentration is crucial for water quality monitoring and is highly desired by various government agencies and environmental groups. However, using satellite observations for Chla estimation remains problematic over coastal waters due to their optical complexity and the critical atmospheric correct...

Current earth observation models do not take into account the influence of water salinity on the evaporation rate, even though the salinity influences the evaporation rate by affecting the density and latent heat of vaporization. In this paper, we adapt the SEBS (Surface Energy Balance System) model for large water bodies and add the effect of wate...

The 2SeaColor model (Salama & Verhoef, 2015) was proposed to analytically retrieve the diffuse attenuation coefficient (Kd) from remote sensing reflectance (Rrs), but its parameterization was based on approximations and subjected to large uncertainties. In this study, we present an improvement on the parameterization equations in the inverse scheme...

With society becoming increasingly cautious and aware of their environment, monitoring and sensor platforms are shifting toward empowering citizens with the capability to collect, process and share information about their environment. In terms of water quality monitoring, the ubiquity of smartphones makes it the better tool to achieve such goal thr...

Mapping Total Suspended Matters from satellite data is hampered by the optical complexity and often extreme turbidity. Extremely high concentrations of Suspended Particulate Matter(SPM), Chlorophyll(Chl) and Coloured Dissolved Organic Matter(CDOM), local differences, seasonal and tidal variations, and resuspension are important factors that lead to...

The use of satellite remote sensing in monitoring chlorophyll-a pigments in all marine and fresh open inland water has been a significant issue in the past decades for preserving and monitoring ecological issues related to aquatic systems. Three small lakes in the Netherlands were used to study Chlorophyll-a (absorption coefficient of pigments/phyt...

Current land surface models (LSMs) tend to largely underestimate the daytime land surface temperature Tsfc for high-altitude regions. This is partly because of underestimation of heat transfer resistance, which may be resolved through adequate parameterization of roughness lengths for momentum z0m and heat z0h transfer. In this paper, the regional-...

The use of in situ measurements is essential in the validation and evaluation of the algorithms that provide coastal water quality data products from ocean colour satellite remote sensing. Over the past decade, various types of ocean colour algorithms have been developed to deal with the optical complexity of coastal waters. Yet there is a lack of...

Quantifying the human effects on water resources plays an important role in river basin management. In this study, we proposed a framework, which integrates the Gravity Recovery and Climate Experiment (GRACE) satellite estimation with macro-scale hydrological model simulation, for detection and attribution of spatial terrestrial water storage (TWS)...

Objective Discus some methods to evaluate the uncertainty of derived IOP from ocean color radiometric data; Rise some questions for further thoughts.

Earth observations (EOs) following empirical and/or analytical approaches are a feasible alternative to obtain spatial and temporal distribution of water quality variables. The limitations observed in the use of empirical approaches to estimate high concentrations of suspended particulate matter (SPM) in the estuarine water of Guadalquivir have led...

The use of in situ measurements is essential in the validation and evaluation of the algorithms that provide coastal water quality data products from ocean colour satellite remote sensing. Over the past decade, various types of ocean colour algorithms have been developed to deal with the optical complexity of coastal waters. Yet there is a lack of...

In this paper we show the potential of combining actual evapotranspiration (ETactual) series obtained from remote sensing and land surface modelling, to monitor community practice in irrigation at a monthly scale. This study estimates blue water evapotranspiration (ETb) in irrigated agriculture in two study areas: the Horn of Africa (2010-2012) and...

The estimation of evapotranspiration of blue water (ETb) from farmlands, due to irrigation, is crucial to improve water management, especially in regions where water resources are scarce. Large scale ETb was previously obtained, based on the differences between remote sensing derived actual ET and values simulated from the Global Land Data Assimila...

Water quality monitoring market is one of the markets that continue to grow. Although the earth observation segment is not one of this market’s largest, it has large growth potential. This is, mainly, due to its capability in providing spatial coverage of water quality variables at repeated time interval. Remote sensing of water quality represents...

This paper discusses soil moisture retrievals over the Tibetan Plateau from brightness temperature (TB's) observed by the Special Sensor Microwave Imagers (SSM/I's) during the warm seasons of the period from July 1987 to December 2008. The Fundamental Climate Data Record (FCDR) of F08, F11 and F13 SSM/I satellites by the Precipitation Research Grou...

This paper discusses soil moisture retrievals over the Tibetan Plateau from brightness temperature (TB's) observed by the Special Sensor Microwave Imagers (SSM/I's) during the warm seasons of the period from July 1987 to December 2008. The Fundamental Climate Data Record (FCDR) of F08, F11 and F13 SSM/I satellites by the Precipitation Research Grou...

In this study, we analyze 32 yr of terrestrial water storage (TWS) data obtained from the Interim Reanalysis Data (ERA-Interim) and Noah model from the Global Land Data Assimilation System (GLDAS-Noah) for the period 1979 to 2010. The accuracy of these datasets is validated using 26 yr (1979–2004) of runoff data from the Yichang gauging station and...

Understanding the sources of uncertainty that cause deviations between simulated and satellite-observed states can facilitate optimal usage of these products via data assimilation or calibration techniques. A method is presented for separating uncertainties following from (i) scale differences between model grid and satellite footprint, (ii) residu...

In this paper, we analyze the standardized anomalies of land surface temperature (LST) retrieved from the Special Sensor Microwave Imager (SSM/I) vertically polarized 37 GHz ( $T^v_{B,37~{\rm GHz}}$ ) brightness temperature over the Tibetan Plateau for the period 1987 to 2008. A radiative transfer model is used to derive LST from SSM/I $T^v_{Bv,...

In this study, we analyze 32 yr of TWS data obtained from Interim Reanalysis Data (ERA-Interim) and Noah model from Global Land Data Assimilation System (GLDAS-Noah) for the period between 1979 and 2010. The accuracy of these datasets is validated against 26 yr (1979-2004) of runoff dataset from Yichang gauging station and compared to 32 yr of inde...

This study presents the application of a semi-empirical approach, based on the Kubelka–Munk (K-M) model, to retrieve the total suspended matter (TSM) concentration of water bodies from ocean colour remote sensing. This approach is validated with in situ data sets compiled from the tropical waters of Berau estuary, Indonesia. Compared to a purely em...

In this paper, we propose an innovative method for identifying irrigated areas and quantifying the blue evapotranspiration (ETb), or irrigation water evapotranspired from the field. The method compares actual ET (ETactual), or crop water use, values from the Global Land Data Assimilation System (GLDAS) and remote sensing based ETactual estimates ob...

The middle reaches of Yarlung Zangbo River (YR) and its two tributaries is a region in central Tibet Autonomous Region where the industrial and agricultural economy is most concentrative and developed. Remote sensing of land surface parameters has significant meaning for crop growth monitoring, crop yield assessment and disaster monitoring. It also...

We present a method to calibrate and validate observational models that interrelate remotely sensed energy fluxes to geophysical variables of land and water surfaces. Coincident sets of remote sensing observation of visible and microwave radiations and geophysical data are assembled and subdivided into calibration (Cal) and validation (Val) data se...

We present a method to calibrate and validate observational models that interrelate remotely sensed energy fluxes to geophysical variables of land and water surfaces. Coincident sets of remote sensing observation of visible and microwave radiations and geophysical data are assembled and subdivided into calibration (Cal) and validation (Val) data se...

The wide swath (WS) and global monitoring (GM) modes of the Advanced Synthetic Aperture Radar (ASAR) provide for monitoring purposes a good compromise between the spatial coverage, spatial resolution and revisit time. Similar imaging modes will be a part of the Sentinel-1 SAR sensing system. A consequence of operating at the wider swath is, however...

The development of an operational water quality monitoring method based on remote sensing data requires information on the apparent and inherent optical properties of water (AOP and IOP respectively). This study was performed to determine the apparent and inherent optical properties of coastal waters of the Mahakam Delta, Kalimantan, Indonesia. Inh...

In this paper we propose an approach to decompose the water footprint (WF) using remote sensing data on a global scale. The WF of a crop is defined as the volume of water consumed for its production, where green and blue WF stand for rain and irrigation water usage, respectively. A method has been developed to separate WF into its green and blue co...

In this chapter, the observation of hydrological processes using remote sensing, which is also commonly called Earth observation of hydrological cycle or Earth observation of water cycle, is briefly described. Earth observation of the different components of the water cycle is described in depth including a summary of the current state of the scien...

Variations of land surface parameters over the Tibetan Plateau have great importance on local energy and water cycles, the Asian monsoon, and climate change studies. In this paper, the NOAA/NASA Pathfinder Advanced Very High Resolution Radiometer (AVHRR) Land (PAL) dataset is used to retrieve the land surface temperature (LST), the normalized diffe...

Sediment fluxes in coastal waters of the Mahakam Delta, Indonesia, play an important role in the quality and dynamics of the estuary and its coastal environments. Excessive concentrations of total suspended matters (TSM) influence the navigational routes and the productivity of Mahakam fluvial and estuarine waters. Therefore, reliable information o...