Detecting microplastics pollution in world oceans using SAR remote sensing

Plastic pollution in the world’s oceans is estimated to have reached 270.000 tones, or 5.25 trillion pieces. This plastic is now ubiquitous, however due to ocean circulation patterns, it accumulates in the ocean gyres, creating “garbage patches”. This plastic debris is colonized by microorganisms which create unique bio-film ecosystems. Microbial colonization is the first step towards disintegration and degradation of plastic materials: a process that releases metabolic by-products from energy synthesis. These by-products include the release of short-chain and more complex carbon molecules in the form of surfactants, which we hypothesize will affect the fluid dynamic properties of waves (change in viscosity and surface tension) and make them detectable by SAR sensor. In this study we used Sentinel-1A and COSMO-SkyMed SAR images in selected sites of both the North Pacific and North Atlantic oceans, close to ocean gyres and away from coastal interference. Together with SAR processing we conducted contextual analysis, using ocean geophysical products of the sea surface temperature, surface wind, chlorophyll, wave heights and wave spectrum of the ocean surface. In addition, we started experiments under controlled conditions to test the behaviour of microbes colonizing the two most common pollutants, polyethylene (PE) and polyethylene terephthalate (PET) microplastics. The analysis of SAR images has shown that a combination of surface wind speed and Langmuir cells- ocean circulation pattern is the main controlling factor in creating the distinct appearance of the sea-slicks and microbial bio-films. The preliminary conclusion of our study is that SAR remote sensing may be able to detect plastic pollution in the open oceans and this method can be extended to other areas

Can We "Sense" the Call of The Ocean? Current Advances in Remote Sensing Computational Imaging for Marine Debris Monitoring

Especially due to the unconscious use of petroleum products, the ocean faces a potential danger: $\textit{plastic pollution}$. Plastic pollutes not only the ocean but also directly the air and foods whilst endangering the ocean wild-life due to the ingestion and entanglements. Especially, during the last decade, public initiatives and academic institutions have spent an enormous time on finding possible solutions to marine plastic pollution. Remote sensing imagery sits in a crucial place for these efforts since it provides highly informative earth observation products. Despite this, detection, and monitoring of the marine environment in the context of plastic pollution is still in its early stages and the current technology offers possible important development for the computational efforts. This paper contributes to the literature with a thorough and rich review and aims to highlight notable literature milestones in marine debris monitoring applications by promoting the computational imaging methodology behind these approaches.Comment: 25 pages, 11 figure

Remote sensing data as a tool to monitor and mitigate natural catastrophes resulting from anthropogenic activities

This thesis demonstrates how remotely sensed satellite acquisitions can be used to addresses some of the natural catastrophes resulting from anthropogenic activities. Examples from both land and water systems are used to illustrate the breath of this toolbox. The effects of global climate change on biological systems and the wellbeing of everyday people are becoming less easy to ignore. In addition, our oceans are facing multiple large-scale stressors, including microplastics as a recently recognized threat, which place at risk the resources which a large percentage of the world’s population depends on for their livelihood. The cause of many of these changes stem from anthropogenic activities, but lacking understanding of complex ecosystems limits our ability to make definite conclusions as to cause and effect. The difficulty to collect on-the-ground data sufficient enough to capture processes working over scales of hundred of kilometers up to the entire globe is often a limitation to research. Remote sensing systems help ameliorate this issue through providing tools to better monitor environmental changes over large areas. The examples provided in this thesis focus on (Section I) tropical peatland fire characteristics and burning in Southeast Asia as a significant contributor to greenhouse gas emissions and (Section II) spread of river-based plastic pollution in coastal ocean systems. Section I specifically focuses on fires within Indonesia, which holds more than half of all known peatlands in the tropical zone and are estimated to represent a carbon pool of 82–92 gigatons. A brief description of recent development activities within Indonesia is presented in Section I of the Introduction, followed by meteorological processes responsible for extended drought periods in the region, and the situation of current fire control within the country. Chapter 1 presents an example of the large improvement in fire detection, as well as measurement of fire front characteristics, provided by a state-of-the-art thermal remote sensing. Chapter 2 goes into detail describing how an active satellite sensor system is able to provide much quicker and more accurate estimates of burned area for the tropics than other existing methods dependent on passive satellite sensor systems. Both these methods provide powerful tools for development of an improved system to monitor fire over Indonesia. The goal of such a monitoring system would be to reduce fire emissions from this large country, which according to global climate models play an important role in global climate change. Section II focuses on aquatic plastic pollution flowing from a freshwater system into the coastal oceans. A background of the issue of plastic pollution along with the current status of plastic debris in both oceans and inland river systems is presented in Section II of the Introduction. Chapter 3 describes development and comparison of two different modelling efforts to display how plastic particles being emitted from a major river are accumulating along the nearby coastline. The goal of this work is to present how remote sensing data could be used to in conjunction with ocean current modelling to create a comprehensive particle tracking monitoring system.Diese Arbeit zeigt, wie aus der Ferne wahrgenommene Satellitenaufnahmen dazu verwendet werden können, sich einigen Naturkatastrophen, die aus anthropogenen Aktivitäten resultieren, zu widmen. Anhand von Beispielen aus Land- und Wassersystemen wird der Umfang dieses technischen Werkzeugkastens dargestellt. Die Auswirkungen des globalen Klimawandels auf biologische Systeme und das Wohlbefinden des Menschen lassen sich nicht mehr ignorieren. Darüber hinaus sind unsere Ozeane mehreren großen Stressfaktoren ausgesetzt, einschließlich Mikroplastik als eine seit kurzem anerkennte Bedrohung, welche die Ressourcen gefährden, von denen der Lebensunterhalt eines großen Teils der Weltbevölkerung abhängt. Die Ursache vieler dieser Veränderungen liegt in anthropogenen Aktivitäten, aber mangelndes Verständnis für komplexe Ökosysteme begrenzt unsere Fähigkeit, eindeutige Rückschlüsse auf Ursache und Wirkung zu treffen. Die Schwierigkeit, Daten vor Ort zu sammeln, die ausreichen, um Prozesse zu erfassen, die über Hunderte von Kilometern bis hin zum gesamten Globus arbeiten, ist oft eine Einschränkung der Forschung. Fernerkundungssysteme tragen dazu bei, dieses Problem zu beheben, indem sie Werkzeuge zur besseren Überwachung von Umweltveränderungen in großen Gebieten bereitstellen. Die Beispiele in dieser Arbeit konzentrieren sich auf („Section I“) Feuermerkmale und Brandflächen der tropischen Torfgebiete in Südostasien als signifikanter Beitrag zu Treibhausgasemissionen und („Section II“) Ausbreitung von Fluss-basiertem Plastikmüll in küstennahen Meeressystemen. Section I konzentriert sich speziell auf die Brände in Indonesien, welches mehr als die Hälfte aller bekannten Torfgebiete in der tropischen Zone besitzt und auf einen Kohlenstoffpool von 82-92 Gigatonnen geschätzt wird. Eine kurze Beschreibung der jüngsten Entwicklungstätigkeiten in Indonesien wird in Section I der Einleitung vorgestellt, gefolgt von meteorologischen Prozessen, die für ausgedehnte Dürreperioden in der Region verantwortlich sind, und der Situation der aktuellen Feuerkontrolle innerhalb des Landes. Chapter 1 zeigt ein Beispiel für die große Verbesserung der Branddetektion sowie die Messung der Brandfronteigenschaften, die durch eine moderne thermische Fernerkundung erreicht werden können. In Chapter 2 wird ausführlich beschrieben, wie ein aktives Satellitensensorsystem in der Lage ist, schnellere und genauere Schätzungen der verbrannten Fläche für die Tropen zu liefern als andere existierende Methoden, die von passiven Satellitensensorsystemen abhängen. Beide Methoden bieten leistungsstarke Werkzeuge für die Entwicklung eines verbesserten Systems zur Brandüberwachung von Indonesien. Ziel eines solchen Überwachungssystems wäre es, Brandemissionen aus diesem großen Land zu reduzieren, das nach globalen Klimamodellen eine wichtige Rolle im globalen Klimawandel spielt. Section II konzentriert sich auf die Verschmutzung von Wasserplastik, die von einem Süßwassersystem in die Küstenmeere fließt. Ein Hintergrund des Problems der Plastikverschmutzung zusammen mit dem gegenwärtigen Status von Plastiktrümmern sowohl in Ozeanen als auch Binnenflusssystemen wird in Section II der Einleitung dargestellt. Chapter 3 beschreibt die Entwicklung und den Vergleich von zwei verschiedenen Modellierungsbemühungen, um zu zeigen, wie sich Kunststoffpartikel, die von einem großen Fluss emittiert werden, entlang der nahen Küstenlinie ansammeln. Das Ziel dieser Arbeit ist zu zeigen, wie Fernerkundungsdaten in Verbindung mit Meeresströmungsmodellierung verwendet werden können, um ein umfassendes Teilchenverfolgungsüberwachungssystem zu schaffen

An overview of techniques associated with remote sensing

Paige, M., & Painho, M. (2015). Detection of exogenous floating marine debris: An overview of techniques associated with remote sensing. In Water Resources Management VIII (Vol. 196, pp. 537 - 548). (WIT Transactions on Ecology and the Environment). DOI: 10.2495/WRM150461Exogenous floating marine debris (EFMD) is a worldwide concern and its ubiquitous characteristics and long-term threat have raised calls for new venues to enable easier and prompt detection at large. The main focus of this paper is to evidence search and detection methods for EFMD using remote sensing techniques. This paper contributes to update research information in the topic under scrutiny and to screen for possible gaps to mitigate EFMD impacts. Several needs for research were found, and, before any work to establish the ground truth could take place, a spectral library model for EFMD going through several stages of biofouling must be created using passive or active research methods. Search methods need to be automated using empirical models based on stratified set-ups previously tested. Several sensors show potential for an indirect search for EFMD, but direct detection of EFMD using multispectral and radar instruments still needs further research through integration with conceptual and empirical modeling techniques.publishersversionpublishe

Riverine Microplastic Quantification: A Novel Approach Integrating Satellite Images, Neural Network, and Suspended Sediment Data as a Proxy

Rivers transport terrestrial microplastics (MP) to the marine system, demanding cost-effective and frequent monitoring, which is attainable through remote sensing. This study aims to develop and test microplastic concentration (MPC) models directly by satellite images and indirectly through suspended sediment concentration (SSC) as a proxy employing a neural network algorithm. These models relied upon high spatial (26 sites) and temporal (198 samples) SSC and MPC data in the Tisza River, along with optical and active sensor reflectance/backscattering. A feedforward MLP neural network was used to calibrate and validate the direct models employing k-fold cross-validation (five data folds) and the Optuna library for hyperparameter optimization. The spatiotemporal generalization capability of the developed models was assessed under various hydrological scenarios. The findings revealed that hydrology fundamentally influences the SSC and MPC. The indirect estimation method of MPC using SSC as a proxy demonstrated higher accuracy (R2 = 0.17–0.88) than the direct method (R2 = 0–0.2), due to the limitations of satellite sensors to directly estimate the very low MPCs in rivers. However, the estimation accuracy of the indirect method varied with lower accuracy (R2 = 0.17, RMSE = 12.9 item/m3 and MAE = 9.4 item/m3) during low stages and very high (R2 = 0.88, RMSE = 7.8 item/m3 and MAE = 10.8 item/m3) during floods. The worst estimates were achieved based on Sentinel-1. Although the accuracy of the MPC models is moderate, it still has practical applicability, especially during floods and employing proxy models. This study is one of the very initial attempts towards MPC quantification, thus more studies incorporating denser spatiotemporal data, additional water quality parameters, and surface roughness data are warranted to improve the estimation accuracy

PICES Press, Vol. 20, No. 1, Winter 2012

•2011 PICES Science: A Note from the Science Board Chairman (pp. 1-6) •2011 PICES Awards (pp. 7-9) •Beyond the Terrible Disaster of the Great East Japan Earthquake (pp. 10-12) •A New Era of PICES-ICES Scientific Cooperation (p. 13) •New PICES Jellyfish Working Group Formed (pp. 14-15) •PICES Working Group on North Pacific Climate Variability (pp. 16-18) •Final U.S. GLOBEC Symposium and Celebration (pp. 19-25) •2011 PICES Rapid Assessment Survey (pp. 26-29) •Introduction to Rapid Assessment Survey Methodologies for Detecting Non-indigenous Marine Species (pp. 30-31) •The 7th International Conference on Marine Bioinvasions (pp. 32-33) •NOWPAP/PICES/WESTPAC Training Course on Remote Sensing Data Analysis (pp. 34-36) •PICES-2011 Workshop on “Trends in Marine Contaminants and their Effects in a Changing Ocean” (pp. 37-39) •The State of the Western North Pacific in the First Half of 2011 (pp. 40-42) •Yeosu Symposium theme sessions (p. 42) •The Bering Sea: Current Status and Recent Events (pp. 43-44) •News of the Northeast Pacific Ocean (pp. 45-47) •Recent and Upcoming PICES Publications (p. 47) •New leadership for the PICES Fishery Science Committee (p. 48

Toward the Integrated Marine Debris Observing System

Plastics and other artificial materials pose new risks to the health of the ocean. Anthropogenic debris travels across large distances and is ubiquitous in the water and on shorelines, yet, observations of its sources, composition, pathways, and distributions in the ocean are very sparse and inaccurate. Total amounts of plastics and other man-made debris in the ocean and on the shore, temporal trends in these amounts under exponentially increasing production, as well as degradation processes, vertical fluxes, and time scales are largely unknown. Present ocean circulation models are not able to accurately simulate drift of debris because of its complex hydrodynamics. In this paper we discuss the structure of the future integrated marine debris observing system (IMDOS)thatisrequiredtoprovidelong-termmonitoringofthestateofthisanthropogenic pollution and support operational activities to mitigate impacts on the ecosystem and on the safety of maritime activity. The proposed observing system integrates remote sensing and in situ observations. Also, models are used to optimize the design of the system and, in turn, they will be gradually improved using the products of the system. Remote sensing technologies will provide spatially coherent coverage and consistent surveying time series at local to global scale. Optical sensors, including high-resolution imaging, multi- and hyperspectral, fluorescence, and Raman technologies, as well as SAR will be used to measure different types of debris. They will be implemented in a variety of platforms, from hand-held tools to ship-, buoy-, aircraft-, and satellite-based sensors. A network of in situ observations, including reports from volunteers, citizen scientists and ships of opportunity, will be developed to provide data for calibration/validation of remote sensors and to monitor the spread of plastic pollution and other marine debris. IMDOS will interact with other observing systems monitoring physical, chemical, and biological processes in the ocean and on shorelines as well as the state of the ecosystem, maritime activities and safety, drift of sea ice, etc. The synthesized data will support innovative multi-disciplinary research and serve a diverse community of users

Toward the integrated marine debris observing system

Plastics and other artificial materials pose new risks to the health of the ocean. Anthropogenic debris travels across large distances and is ubiquitous in the water and on shorelines, yet, observations of its sources, composition, pathways, and distributions in the ocean are very sparse and inaccurate. Total amounts of plastics and other man-made debris in the ocean and on the shore, temporal trends in these amounts under exponentially increasing production, as well as degradation processes, vertical fluxes, and time scales are largely unknown. Present ocean circulation models are not able to accurately simulate drift of debris because of its complex hydrodynamics. In this paper we discuss the structure of the future integrated marine debris observing system (IMDOS) that is required to provide long-term monitoring of the state of this anthropogenic pollution and support operational activities to mitigate impacts on the ecosystem and on the safety of maritime activity. The proposed observing system integrates remote sensing and in situ observations. Also, models are used to optimize the design of the system and, in turn, they will be gradually improved using the products of the system. Remote sensing technologies will provide spatially coherent coverage and consistent surveying time series at local to global scale. Optical sensors, including high-resolution imaging, multi- and hyperspectral, fluorescence, and Raman technologies, as well as SAR will be used to measure different types of debris. They will be implemented in a variety of platforms, from hand-held tools to ship-, buoy-, aircraft-, and satellite-based sensors. A network of in situ observations, including reports from volunteers, citizen scientists and ships of opportunity, will be developed to provide data for calibration/validation of remote sensors and to monitor the spread of plastic pollution and other marine debris. IMDOS will interact with other observing systems monitoring physical, chemical, and biological processes in the ocean and on shorelines as well as the state of the ecosystem, maritime activities and safety, drift of sea ice, etc. The synthesized data will support innovative multi-disciplinary research and serve a diverse community of users

Preliminary characterization of microwave backscattering of floating plastic

Microwaves (MW) may offer advantages over optical techniques for remote monitoring of marine litter. However, no systematic studies are found in the literature about microwave sensing of floating plastics. In order to assess the potential, we carried out two types of experiments and analysis. In one scenario we measured and characterized the MW backscatter of different densities of typical plastic bottles and jerry cans, floating in a small pool of static water. The results show a significant increase of litter response with litter density, thus demonstrating that floating plastic affects the MW backscattering of the water surface. In the second scenario, we assembled a setup to resemble a synthetic aperture radar system: a small container filled with water and floating plastic was linearly translated under a fixed antenna operating in monostatic mode; we have successfully reconstructed the energy backscattering map of the target. This preliminary work demonstrates that floating macro plastics do present a MW signature that may be relevant for remote monitoring of this type of marine pollution.info:eu-repo/semantics/acceptedVersio

Remote sensing data as a tool to monitor and mitigate natural catastrophes resulting from anthropogenic activities

This thesis demonstrates how remotely sensed satellite acquisitions can be used to addresses some of the natural catastrophes resulting from anthropogenic activities. Examples from both land and water systems are used to illustrate the breath of this toolbox. The effects of global climate change on biological systems and the wellbeing of everyday people are becoming less easy to ignore. In addition, our oceans are facing multiple large-scale stressors, including microplastics as a recently recognized threat, which place at risk the resources which a large percentage of the world’s population depends on for their livelihood. The cause of many of these changes stem from anthropogenic activities, but lacking understanding of complex ecosystems limits our ability to make definite conclusions as to cause and effect. The difficulty to collect on-the-ground data sufficient enough to capture processes working over scales of hundred of kilometers up to the entire globe is often a limitation to research. Remote sensing systems help ameliorate this issue through providing tools to better monitor environmental changes over large areas. The examples provided in this thesis focus on (Section I) tropical peatland fire characteristics and burning in Southeast Asia as a significant contributor to greenhouse gas emissions and (Section II) spread of river-based plastic pollution in coastal ocean systems. Section I specifically focuses on fires within Indonesia, which holds more than half of all known peatlands in the tropical zone and are estimated to represent a carbon pool of 82–92 gigatons. A brief description of recent development activities within Indonesia is presented in Section I of the Introduction, followed by meteorological processes responsible for extended drought periods in the region, and the situation of current fire control within the country. Chapter 1 presents an example of the large improvement in fire detection, as well as measurement of fire front characteristics, provided by a state-of-the-art thermal remote sensing. Chapter 2 goes into detail describing how an active satellite sensor system is able to provide much quicker and more accurate estimates of burned area for the tropics than other existing methods dependent on passive satellite sensor systems. Both these methods provide powerful tools for development of an improved system to monitor fire over Indonesia. The goal of such a monitoring system would be to reduce fire emissions from this large country, which according to global climate models play an important role in global climate change. Section II focuses on aquatic plastic pollution flowing from a freshwater system into the coastal oceans. A background of the issue of plastic pollution along with the current status of plastic debris in both oceans and inland river systems is presented in Section II of the Introduction. Chapter 3 describes development and comparison of two different modelling efforts to display how plastic particles being emitted from a major river are accumulating along the nearby coastline. The goal of this work is to present how remote sensing data could be used to in conjunction with ocean current modelling to create a comprehensive particle tracking monitoring system.Diese Arbeit zeigt, wie aus der Ferne wahrgenommene Satellitenaufnahmen dazu verwendet werden können, sich einigen Naturkatastrophen, die aus anthropogenen Aktivitäten resultieren, zu widmen. Anhand von Beispielen aus Land- und Wassersystemen wird der Umfang dieses technischen Werkzeugkastens dargestellt. Die Auswirkungen des globalen Klimawandels auf biologische Systeme und das Wohlbefinden des Menschen lassen sich nicht mehr ignorieren. Darüber hinaus sind unsere Ozeane mehreren großen Stressfaktoren ausgesetzt, einschließlich Mikroplastik als eine seit kurzem anerkennte Bedrohung, welche die Ressourcen gefährden, von denen der Lebensunterhalt eines großen Teils der Weltbevölkerung abhängt. Die Ursache vieler dieser Veränderungen liegt in anthropogenen Aktivitäten, aber mangelndes Verständnis für komplexe Ökosysteme begrenzt unsere Fähigkeit, eindeutige Rückschlüsse auf Ursache und Wirkung zu treffen. Die Schwierigkeit, Daten vor Ort zu sammeln, die ausreichen, um Prozesse zu erfassen, die über Hunderte von Kilometern bis hin zum gesamten Globus arbeiten, ist oft eine Einschränkung der Forschung. Fernerkundungssysteme tragen dazu bei, dieses Problem zu beheben, indem sie Werkzeuge zur besseren Überwachung von Umweltveränderungen in großen Gebieten bereitstellen. Die Beispiele in dieser Arbeit konzentrieren sich auf („Section I“) Feuermerkmale und Brandflächen der tropischen Torfgebiete in Südostasien als signifikanter Beitrag zu Treibhausgasemissionen und („Section II“) Ausbreitung von Fluss-basiertem Plastikmüll in küstennahen Meeressystemen. Section I konzentriert sich speziell auf die Brände in Indonesien, welches mehr als die Hälfte aller bekannten Torfgebiete in der tropischen Zone besitzt und auf einen Kohlenstoffpool von 82-92 Gigatonnen geschätzt wird. Eine kurze Beschreibung der jüngsten Entwicklungstätigkeiten in Indonesien wird in Section I der Einleitung vorgestellt, gefolgt von meteorologischen Prozessen, die für ausgedehnte Dürreperioden in der Region verantwortlich sind, und der Situation der aktuellen Feuerkontrolle innerhalb des Landes. Chapter 1 zeigt ein Beispiel für die große Verbesserung der Branddetektion sowie die Messung der Brandfronteigenschaften, die durch eine moderne thermische Fernerkundung erreicht werden können. In Chapter 2 wird ausführlich beschrieben, wie ein aktives Satellitensensorsystem in der Lage ist, schnellere und genauere Schätzungen der verbrannten Fläche für die Tropen zu liefern als andere existierende Methoden, die von passiven Satellitensensorsystemen abhängen. Beide Methoden bieten leistungsstarke Werkzeuge für die Entwicklung eines verbesserten Systems zur Brandüberwachung von Indonesien. Ziel eines solchen Überwachungssystems wäre es, Brandemissionen aus diesem großen Land zu reduzieren, das nach globalen Klimamodellen eine wichtige Rolle im globalen Klimawandel spielt. Section II konzentriert sich auf die Verschmutzung von Wasserplastik, die von einem Süßwassersystem in die Küstenmeere fließt. Ein Hintergrund des Problems der Plastikverschmutzung zusammen mit dem gegenwärtigen Status von Plastiktrümmern sowohl in Ozeanen als auch Binnenflusssystemen wird in Section II der Einleitung dargestellt. Chapter 3 beschreibt die Entwicklung und den Vergleich von zwei verschiedenen Modellierungsbemühungen, um zu zeigen, wie sich Kunststoffpartikel, die von einem großen Fluss emittiert werden, entlang der nahen Küstenlinie ansammeln. Das Ziel dieser Arbeit ist zu zeigen, wie Fernerkundungsdaten in Verbindung mit Meeresströmungsmodellierung verwendet werden können, um ein umfassendes Teilchenverfolgungsüberwachungssystem zu schaffen