GROW Observatory

The GROW Observatory – an EU-wide ‘citizen science’ project for growers, gardeners, small and family farmers, and space scientists

The GROW Observatory (GROW) is a massive, European-wide project aiming to involve tens of thousands of ‘citizen scientists’ that will empower growers with knowledge on sustainable practices and make a vital contribution to global environmental monitoring.

Together they will solve key challenge for environmental monitoring – the ability to measure soil moisture at high spatial resolution over large geographical areas – whilst sharing knowledge on growing in different regions. The aim will be to increase small-scale food production and preserve the soil quality for future generations, whilst improving forecasting of extreme climate events, such as heat waves and floods.

Led by the University of Dundee and including partners across Europe, the GROW Observatory has received funding of €5million over the next three years through the European Commission’s Horizon 2020 programme. The project starts on 1st November 2016, and will engage growers and citizen scientists to help co-create the experiments during the 2017 growing season.

GROW aims to underpin smart and sustainable custodianship of land and soil, with a view to meeting the future demands of food production. It also aims to answer a long¬standing challenge for space science – by helping to validate the detection of soil moisture from satellites. GROW will look at how this data can contribute to services and applications that help forecast and prepare for extreme climate events, such as heat waves and floods.

“This is citizen science on an unprecedented scale” said Dr Drew Hemment, who is leading the project from Duncan of Jordanstone College of Art & Design, part of the University of Dundee. “People taking part will collaborate to create and share information on soil, the land, on crops – what to plant, when to plant them and how to do it. They will be able to develop knowledge and skills on soil and growing for food, and take practical steps to preserve the soil for future generations.”

To achieve this GROW will combine low cost sensing technology combined with citizens’ own devices, a simple soil test, innovative data handling and an online education platform to mobilise large numbers of citizens across Europe.

“The vision is to support the emergence of a movement of citizens sharing data and knowledge on growing and the land, to increase access to affordable food, preserve the soil for future generations, and solve a major challenge for science,” said Dr Hemment. “GROW will build a community of thousands of growers, gardeners, smallholders and citizen scientists across Europe to harness the collective power of shared and open data and knowledge.

“Do you grow your own food? Do you have an allotment? Own a small farm? Or have a community or school garden? Do you want to develop your knowledge and skills on soil and growing for food, and take practical steps to preserve the soil for future generations? Or collaborate with thousands of people to solve a longstanding challenge for space science?

“If the answer to any of these questions is `yes’ then GROW is a project we hope people will really engage with. This will be a platform and community for large scale citizen science that aims to empower growers with knowledge on sustainable practices and make a vital contribution to global environmental monitoring.

“The outcome will be a hub of open knowledge and data created and maintained by growers that will be of value to the citizens themselves as well as specialist communities in science, policy and industry. GROW will generate, share and utilise information on land, soil and water resource at a resolution hitherto not previously considered.

“By providing our community with simple testing kits and technology, we can gather information across the continent on a range of parameters relevant to growing. So we will have a Europe-wide network with citizen scientists at the heart of it, working alongside policymakers and scientists.

“We can then share knowledge and advice across our community, as well as using it to inform wider science and research.”

GROW presents its first public event on 10th September near Rome, running a workshop at a gathering of committed growers from across European to discover the challenges it can help them to address. Details of upcoming job opportunities at The GROW Observatory can be found here


The European Commission through Horizon 2020 is supporting the development of an ecosystem of Citizen Observatories. The vision is to create a movement around environmental observations to inform and empower citizens to participate in environmental decision making, leading towards more inclusive, sustainable and smart economic development.

Citizen science has a long history, and increasing availability of smartphones and low-cost sensing technologies has opened up new possibilities for collaborative data collection and sense making.

The world faces the challenge of producing sufficient high-quality food while reducing carbon emissions and preserving the quality of land and soil resources.

A key challenge for environmental monitoring is the ability to measure soil moisture at high spatial resolution over large geographical areas.

GROW will offer

  1. Simple, fun experiments to do with friends, family or your community.
  2. Low cost but high power consumer sensing technology, a simple to use soil testing kit, and easy applications, to lower barriers to entry.
  3. A Massive Open Online Course (MOOC) to enable scaling of rigorous citizen science.
  4. Engagement underpinned by storytelling and community champions.


A community of institutes, associations, companies and individuals have come together to create GROW.

  • University of Dundee
  • International Institute for Applied Systems Analysis
  • Food and Agriculture Organisation of the United Nations
  • Met Office
  • Hydrologic Research
  • Starlab
  • FutureEverything
  • European Network for Community-Led Action on Climate Change and Sustainability (ECOLISE)
  • Cultivate
  • CulturePolis
  • Parrot
  • James Hutton Institute
  • Vienna University of Technology
  • Thingful
  • Institute for Advanced Architecture of Catalonia
  • Storythings
  • University of Miskolc
  • The Forest Trust

This project has received funding from the European Union’s Horizon 2020 research and innovation programme 2014 -2018 under grant agreement No 690199.

Starlab will be in the Mobile World Congress 2015

We are very pleased to announce that Starlab will be participating in the coming “GSMA Mobile World Congress 2015” that will take place in Barcelona, Spain over the course of four days, 2-5 March 2015.

With more than 85.000 attendees last year and increasing this year, the GSMA Mobile World Congress attracts the largest number of highest-quality attendees of any event in the mobile industry.

Starlab Barcelona will attend via Generalitat de Catalunya and will be presenting its SmartCities oriented products and services, such as the SmartIrrigation system (a web-based soil moisture information service for irrigation management) and iArbol (a tree health monitoring system based on Earth observation techniques).

If you want to know more, please come meet us at stand CS50 – 13



Smart City Expo World Congress 2014 – Starlab

Smart City Expo Logo

Starlab is participating in the coming “Smart City Expo World Congress 2014” that will take place in Barcelona, Spain on November 18th, 19th and 20th at Gran Via Exhibition Center (l’Hospitalet de Llobregat).



The Congress and Expo Area had visitors from 293 world cities from 80 countries last year, with 300 speakers and 3000 delegates attending.

Starlab Barcelona will attend via Generalitat de Catalunya stand presenting its SmartIrrigation system, lately modified to be used in Parks and City Gardens.  Moreover, the tree health monitoring system called “iArbre” will also be presented.

TalpProbeSmartIrrigation is a web-based soil moisture information service for irrigation management that integrates data from our specifically designed on-site sensors with space imaging. With the objective of knowing the soil moisture, temperature and EC levels in real time, Ajuntament de Barcelona main council deployed an integrated sensor network to gather information about their parks and to control irrigation treatments in a more precise way.

Being able to control irrigation amounts allowed Parcs i Jardins de Barcelona to optimise water levels applied maintaining the desired level of humidity at all times.

On the other hand, a novel and innovative service was tested this summer in Barcelona city. iArbol is a tree health monitoring system based on Earth Observation techniques, that measures the Vegetation Index of trees from the space.

Smart City Expo Pic2

Come meet us at stand B232 (Generalitat de Catalunya)!

The WeSenseIt project: crowdsourcing information on water

As you may have heard, there’s quite a bit of talk out about the role that citizens can play in science and decision-making. If you think about it, I’m sure you’ve heard of smartphone apps that use people’s individual knowledge to build collective knowledge and eventually services for others. Think of apps for informing about accidents on the highway, or for reporting a fallen tree in your neighbourhood, or for giving your report of the weather in your area… the list of ideas is endless. If we could harness (and foster) these individual acts of solidarity to have better information about our environment, the fields of science, decision-making and citizen empowerment can all benefit.

The spheres of influence of the citizen observatory of water in WeSenseIt (©WeSenseIt consortium, 2012)

The spheres of influence of the citizen observatory of water in WeSenseIt (©WeSenseIt consortium, 2012)

The European institutions have realised the potential that this concept poses and as such launched the first call for proposals to research on the subject of citizen science in 2012. Five projects were funded by this call for proposals, each of them with a different thematic focus although all with citizens at the centre of their work.

The projects are WeSenseIt, Cobweb, CITI-SENSE, Citclops, and OMNICIENTIS. These projects are providing the first foundation and experience of how citizens can be involved as key providers of data and fundamental participants of decision-making processes.

In the case of Starlab, we are one of the partners involved in WeSenseIt, a citizen observatory of water. This is a 4-year research project that started in October of 2012 and will end in 2016. The project aims at allowing citizens and communities to become active stakeholders in capturing and communicating information related to water. This engagement will empower these citizens to have a say in their community and help decision-makers access information that was previously absent allowing them to fill gaps in their knowledge.

The concept of a heterogeneous citizen-based observatory of water combining traditional measurements and operational monitoring with citizen-supported observation and information. © Solomatine, Chacon-Hurtado, Segura, UNESCO-IHE

The concept of a heterogeneous citizen-based observatory of water combining traditional measurements and operational monitoring with citizen-supported observation and information.
© Solomatine, Chacon-Hurtado, Segura, UNESCO-IHE

The WeSenseIt project revolves around 3 case studies in different locations around Europe, where water affects people’s lives in different ways: Doncaster (UK), Alto Adriatico (Italy) and Delftland (the Netherlands).

Each of these case studies has a different angle in the way they involve the citizens in their area and in their issues with water. Flooding is an issue in both Doncaster and Alto Adriatico. Involving citizens in areas frequently affected by floods can provide timely information to emergency responders on the status of watercourses in the event of a flood and therefore can help authorities to take better-informed decisions on evacuation efforts. The Delftland case study is mostly centred on involving citizens in providing additional information on water resources and water infrastructures (such as dykes) in a country that has some of the most advanced water monitoring systems in the world.

Our project provides citizens and authorities a wide range of ways of providing and receiving more information on water. The project involves a number of SMEs who develop different types of sensors (rain sensors, water flow sensors, soil moisture sensors, river level sensors, smartphone apps, among others), which with a larger or smaller involvement of citizens can provide additional (previously unavailable) information. In addition to this, other partners in the projects are also conducting important research on how information posted by people on social networks (Twitter and Facebook mainly), can be used to gain additional information about water-related emergencies and even detect and predict certain phenomena occurring.

As far as Starlab’s contribution to the WeSenseIt project, we have provided a set of soil moisture sensors to each of the case studies, which have been installed in relevant locations to monitor different phenomena. In some cases, the intention is to have a better idea of the level of saturation of the soil and to which extent rainfall or rising water level is responsible for this. In other cases our sensors have been installed on the levies that line the riverbanks, to have an early warning of rising river level and provide more data for the hydrological modelling of certain catchments. So, even though the main target sector for our soil moisture is agriculture, they can actually be installed just as well for other purposes. Our next steps in the project will be to provide satellite data-derived information on soil moisture and vegetation health, which combined with data from our soil moisture sensors, should help farmers become more aware of their use of water and provide them information to use it more efficiently.

The installation of one of Starlab's soil moisture sensors in agricultural fields in the Alto Adriatico case study (© E. Solà)

The installation of one of Starlab’s soil moisture sensors in agricultural fields in the Alto Adriatico case study (© E. Solà)

If you’re interested in learning more about the WeSenseIt project, head over to the project website ( and the common citizen observatories website ( And if you’d like more information on our technology, don’t hesitate to leave us a message in the comments section or have a closer look at our products and solutions for water and agriculture.

In relation to this I had the honour of being interviewed on Spanish National Radio last week to talk about the WeSenseIt project (the interview is in Spanish). If you’re interested you can listen to it on the following link: (after minute 34:30 approximately).

Jellyfish forecasting coming to a beach near you!

Jellyfish are fascinating creatures. Although they are able to swim, most of their lifecycle they drift with the currents and in some cases even with the wind. Within the two thousand species of jellyfish known, there is an enormous variability of colours, transparencies, sizes and shapes.

Sea Nettle (Chrysaora fuscescens) Jellyfish in captivity in the Monterey Bay Aquarium

Sea Nettle (Chrysaora fuscescens) jellyfish in captivity at the Monterey Bay Aquarium (copyright: Brocken Inaglory, 2007)

Their diet consists mainly of plankton, although some of them also eat small marine animals (usually, in larval state). In order to eat, jellyfish catch their victims using their tentacles, which are covered in toxic stingers. This method, which has been improved over 650 millions years, has allowed them to be some of the oldest multi-organic animals on Earth (by comparison, the first primates appeared only 60 million years ago).

Up to here, we can’t say much against these beautiful animals. However, the coexistence between jellyfish and humans has been getting more complicated lately, mainly due to their large proliferation and the increased presence of human activities along the coast over the last decades. The same tentacles that jellyfish use for eating can be a serious problem for humans. Their stings may incur anything from a mild rash to severe pain, spasms, and in some cases even cardiac arrest. Fortunately for those of us in this area of the world, most of the cases reported in the Mediterranean Sea are mild rashes, so they’ll just ruin a nice beach day at the most.


Less marine turtles in the Mediterranean are thought to be one of the causes behind jellyfish populations rising (the picture is of a green turtle off Hawaii. Copyright: Brocken Inaglory, 2005)

Climate change, increasing marine pollution and other factors such as a decreasing populations of the jellyfish’s predators (marine turtles, for example) have increased the number of jellyfish reaching our shores over the past few years. Public and private institutions have become concerned about this fact and have increased their interest in finding ways of reducing jellyfish numbers, as well as offering jellyfish alert systems. In the latter case, these types of systems offer beachgoers helpful information to decide what beach to spend the day on during their holidays.

At Starlab, after conducting several projects in the Mediterranean (Catalonia) and the North Atlantic, we have developed a service that allows us to predict the presence of jellyfish on our shores. In particular, during the different Mediterranean campaigns our system achieved a successful prediction accuracy of around 88%.


Jellyfish warning sign (copyright: Wikipedia)

For the proper operation of our jellyfish prediction system, Starjelly, we require an initial collection campaign of beach observations. During this collection campaign, for each observation the presence/absence of jellyfish is reported. Once this campaign is done, we feed this data to the system, which determines through learning algorithms what marine conditions lead to the appearance or absence of jellyfish in a particular spot. More concretely, the system learns which levels of salinity, temperature, currents, surface sea height and other values are conducive to the appearance/absence of jellyfish. This information on the marine conditions is obtained from satellites (earth observation data) such as those of the European Copernicus Sentinel constellation. This way, once the system has learnt which conditions have been given in each case, it can evaluate new data and provide a risk level for jellyfish appearance on a certain beach.

For more information on the service we’ve developed, you can go to the product lines section located on our website. We’re also looking forward to receiving any comments from our readers… are jellyfish also a problem on the beaches where you live?

The importance of remote sensing to monitor urban growth


© Geography GCSE

In recent decades the role of urban growth management has expanded at an accelerating rate as human populations grow and occupy ever-increasing space on the Earth’s surface. The twenty-first century is the first “urban century,” according to the United Nations Development Program. The focus on cities reflects awareness of the growing percentage of the world’s population that lives in urban areas. The need for technologies that will enable monitoring the world’s natural resources and urban assets and managing exposure to natural and man-made risks is growing rapidly. This need is driven by continued urbanization. In the year 2000, about 3 billion people, representing about 40% of the world’s population, lived in urban areas. Urban population will continue to rise substantially over the next several decades according to the United Nations, and most of this growth will be in developing countries.

As one data source, remotely sensed data are inherently suited to provide information on urban land cover characteristics, and their changes over time, at various spatial and temporal scales. The availability of multi-decade remote sensing information provides an important source for monitoring and assessing urban growth and its influences on the environment and ecosystem. Las Vegas as an example is the fastest growing city in the USA. Intense growth has been associated with most of Las Vegas’ 100-year history, with every decade since 1930 experiencing a population increase between 60% and 194%. Since 1990, the population has grown from approximately 750,000 to 2 million residents, which has caused the city’s problematic increases in resource demand. Series of false-color Landsat satellite captures shows its incredible capability of monitoring the urban expansion from 1979 to 2010 as it shown in figure below were vegetation is shown as red – the largest red areas are mostly parks and golf courses – buildings are grey.


40 Years of Las Vegas Sprawl, as Seen From Space. ©

 Day after day we became convinced that remote sensing opens up enticing new prospects for comparing cities in terms of functional interrelationships and indicators of well-being, and the integration of the study of spatial forms with an understanding of the social, economic, cultural and political dimensions that led to their creation. We should not ignore that the exploitation of remote sensing data in urban areas has been a challenge for quite some time because of the complexity and fragmentation of objects and the combination of manmade and natural features. From that point on, the challenge is to accurately map these features, and then to monitor change over time, and ultimately to model and predict the temporal/spatial dimension of change.

Hopefully we can be certain that the increase in spatial and spectral resolution has led to the ability to characterize, and more importantly quantify, urban land uses and monitor their change. This new ability has had a powerful political impact as well. However, during the post-industrial age, the importance of monitoring conversion of agriculture to urban lands is of national, and even global, concern. As global population increases and cities continue to grow, the most fertile farmlands are being urbanized; this has serious implications for the long-term health of planet.

In conclusion, remote sensing data has proved to be significant for monitoring and detecting urban change, and for providing essential information for future development, the constantly increasing availability and accessibility of modern remote sensing technologies provides the unique capability to support decision-making with spatial, quantitative data and information products to open up new opportunities for urban monitoring.


[1]          Remote Sensing of Human Settlements. Andrew B. Rencz, Editor-in-Chief; Volume Editors: Merrill K. Ridd & James D. Hipple. pp. 380, ISBN 1-57083-077-0, 2006.
[2]          U.S. Census Bureau, Clark County, Nevada, accessed December 11, 2010:
[3]          Fusion of spectral and shape features for identification of urban surface cover types using reflective and thermal hyperspectral data. Segl K, Roessner S, Heiden U, & Kaufmann H, ISPRS Journal of Photogrammetry and Remote Sensing, 58/1-2, 99- 112, 2003.
[4]          Urban/Suburban Land Use Analysis. Jensen, J.R., Manual of Remote Sensing, Second Edition (R.N. Colwell, editor), American Society of Photogrammetry, Falls Church, Virginia, pp. 1571-1666, 1983.
[5]          Using nighttime DMSP/OLS images of city lights to estimate the impact of urban land use on soil resources in the united state. Inhoff, Marc L., William T. Lawrence, Christopher D. Elvidge, Tera Paul, Elissa Levine, Maria V. Privalsky, and Virginia Brown. Remote Sensing of Enviroment, 59: 105-117, 1997.
[6]          Remote Sensing – An Effective Data Source for Urban Monitoring. H. Taubenböck and T. Esch, Earth Observation, Urban Monitoring Theme, July 20th 2011.

Copérnico: del sol a la tierra y el programa europeo de observación de la tierra

Nicolás Copérnico, padre de la astronomía moderna, formuló la teoría heliocéntrica del sistema solar en el Renacimiento, una verdadera revolución para aquel entonces. Afirmar que el hombre y la tierra no eran el centro del universo, y que los planetas giraban entorno al sol tuvo grandes repercusiones en el ámbito científico, teológico y filosófico de la época.


Nicolás Copérnico (retrato de Toruń, Polonia, principios del S XVI)

Hace pocos meses que se ha rebautizado al programa (antiguo GMES) más ambicioso de la Comisión Europea (CE), la Agencia Espacial Europea (ESA) y la Agencia de Medio Ambiente Europea (EEA) como Copernicus, pero, ¿de qué se trata? ¿cuál es realmente el objetivo del programa?

Es algo tan sencillo de decir como difícil de realizar: poner los satélites al servicio de la sociedad. Y es que, en realidad es ese el objetivo final de la tecnología: conseguir un impacto social directo y palpable.

Cuando oímos hablar de satélites imaginamos la más avanzada tecnología, algo lejano y de difícil acceso. Esa idea podía encajar en los tiempos de la carrera espacial, o incluso en los años 80, quizás 90, donde se daba más importancia a los ámbitos tecnológicos; ahora el concepto es totalmente diferente.

El mejor ejemplo hasta la fecha es el GPS. Desde hace unos años todos hemos experimentado en nuestro día a día cómo los satélites pueden contribuir a hacer nuestra vida mas fácil con aplicaciones como el GPS. Los satélites que integran la constelación GPS (de la NASA) y GALILEO (de la ESA) son satélites de navegación; es decir, la información que tienen hace referencia a un posicionamiento y su aplicación fundamental, aunque no la única, es la de ubicar con precisión un usuario sobre la superficie terrestre y con esta información proporcionar infinitas aplicaciones como indicar la ruta que debe seguir una persona hacia un punto determinado y muchas más.

Los satélites que integran el programo Copernicus no son satélites de navegación sino satélites de observación de la tierra literalmente, es decir, centinelas que orbitan y observan la tierra continuamente con el fin de que la explotación de los datos que proporcionan mejoren nuestra calidad de vida.

Los Sentinel, nombre con el cual se ha bautizado a los satélites que integran el eje fundamental del programa, toman imágenes de la tierra con diferentes sensores y tecnologías para obtener de ellas parámetros de alta importancia.


El satélite de observación de la tierra Sentinel 1 (copyright: ESA/ATG medialab, 2014)

Analizando los datos de tales satélites se extraen parámetros como la cantidad de nieve almacenada en las montañas, las manchas de petróleo en el océano, la concentración de clorofila o las floraciones de algas en los mares y lagos, la detección de movimientos sísmicos, o bien de la erosión de la línea de costa. Estos son solo unos pocos ejemplos de la gran potencialidad de los Sentinel, cuyo primer satélite, Sentinel-1, orbita alrededor de la tierra desde el pasado 3 de abril.

Con todos estos parámetros pueden darse servicios de gran utilidad a gobiernos, autoridades públicas e instituciones medio ambientales fundamentalmente, tales como apoyos a servicios de emergencia, seguridad, marítimos, atmosféricos y climatológicos, que van desde el seguimiento de incendios, de áreas inundadas o actividad sísmica hasta el control de fronteras, estado de los casquetes polares o incluso aplicaciones tan variadas como un inventario de las zonas agrícolas o urbanas del planeta, entre tantos.


Un mapa de las recientes inundaciones ocurridas en Serbia en mayo de 2014, elaborado a partir de datos proporcionados por Sentinel 1 (copyright: ESA/European Commission, 2014)

Como vemos, el programa Copérnico, y su pequeño ejercito de Centinelas, tienen la misión de velar por la tierra cumpliendo el objetivo fundamental que enunciábamos antes; es decir, sirviendo a la sociedad con la más avanzada tecnología y el esfuerzo conjunto de muchas personas y organismos internacionales para gestionar complicadas tareas de emergencia y seguridad con una información global, precisa y rápida como nunca antes se ha hecho.

Y volviendo al inicio, nos encontramos de nuevo con Copérnico, que postulaba que todo giraba alrededor del sol, y nunca imaginó que irónicamente el hombre, egocéntrico por naturaleza, utilizaría su nombre para un programa cuyo eje central vuelve a ser precisamente de nuevo la Tierra.

Así que Copérnico, lo quiera o no, vuelve a orbitar entorno a la Tierra, aunque dada la envergadura, objetivos y logros ya alcanzados por tal programa, creo que estaría de acuerdo; todo sea por la causa.

When will the snow turn into electricity this year?

In the northern hemisphere, we are now thinking about going to the beach safely and growing fruits and vegetables efficiently. However, on the other side of the globe, snow has started to fall on the mountains, covering the summits with a pristine white mantle.

For hydropower companies in the Southern Hemisphere, this is the signal for starting operation planning: In September, the accumulated snow will start to melt under the spring sun and will become available in the form of water loaded with potential energy, eager to spin the turbines of massive dams producing clean electricity.

Laja lake

View from the Laja Reservoir, Bio Bio Region, Chile

But how can we reliably forecast the quantity of energy stored in the mountains? and how can we know when it will be available? In the case of fossil fuel, it’s easy: the available power is proportional to the quantity of petrol, coal, uranium that you buy. For hydropower, just like for wind power, the raw material cannot just be added to a shopping list. It is a gift of nature and as such it can be highly unpredictable, especially in these times of climate change.

Hydropower operation planners usually rely on a historical set of climatological data, say 30, 40 or 50 years long. By looking at the beginning of the melting season, and at some field parameters, they estimate the available water for the rest of the melting season. However, if the year is really different from the historical set, or if an extreme unexpected event occurs, the forecast will not be accurate.

A new forecast system

To overcome this important limitation, Star2Earth created, together with its partner Future Water, a new monitoring and forecasting system called Hydroflow. This service, originally developed for ENDESA Chile, with the support of the European Space Agency, provides an alternative tool for short and medium term water flow forecast.

Hydroflow operational system overview

Hydroflow operational system overview

The Hydroflow forecast system is based on a state-of-the-art distributed hydrological model fed with observations of physical parameters such as temperature, rain, snowfalls, snow cover and solar radiation, measured by both in situ sensors and satellite data in near real-time. In this way, the hydrological model water-related variables are always up-to-date with respect to the actual state of the area of interest. The model is then able to forecast accurately the water flow by simulating and extrapolating in time the physical processes influencing the water balance such as melting, runoff, infiltration.

The water forecasts, as well as all the measured physical parameters are available for the client through a user-friendly web-based decision support system, updated in real time. Weekly forecast bulletins are also sent automatically to the required persons, easing the planning and decision-making processes.

A versatile service

Hydroflow interface screenshot

Hydroflow web interface screenshot

By using up-to-date observations from the terrain, Hydroflow produces results that are independent from the existence of similar climatological conditions in the historical records, therefore removing one of the most important limitations of the current systems. Hydroflow can also reflect the effects of extreme and unexpected events in a more dynamic way. One of the others main advantages of Hydroflow is that the system can theoretically be adapted to any new geographical area, and no matter the remoteness of the sites to be monitored, as satellite telecommunications systems can be used to transfer automated field measurements in real time.

The latest version of the service, currently under development, is able to take into account man-made changes on the basin such as deviations, canals and extractions. In this way, the forecasts provided by the system are not only reflecting the natural flows in the area of interest, but also synthetic operational flows, sometimes better suited to the needs of the industry.

Satellite Earth Observation: estimating soil moisture content

Sputnik 1

Sputnik-1, planet Earth’s first artificial satellite

Earth observation satellites have been constantly flying over our heads for the past fifty years, mapping and monitoring our planet’s structure, resources and state.

The first satellite (Sputnik-1), not bigger than a beach ball, was launched in 1957 and transmitted radio signals, that could be received on Earth. These signals were used to gather information about the density of the upper layers of the atmosphere and the propagation of electromagnetic waves in the ionosphere. Since then technological advances have allowed us to put in orbit very sophisticated sensors that are able to measure the electromagnetic radiation emitted or reflected by the Earth’s surface and atmosphere with high accuracy. These measurements can be then used to extract information on many geophysical properties. In this post, and the ones that will follow, we will try to give a closer look to the different geophysical variables that it is possible to measure from space and how they can be used for practical applications. We will start the overview explaining how soil moisture is estimated from satellite measurements and how it can be used for irrigation water management.

Water is an essential resource in general but especially in areas where it is scarce and in big areas of farming activity. By definition, water management represents the use of the proper quantity of water at the proper time and it is usually pursued by combining measurements of soil moisture with an optimised irrigation plan. While the second element is easy to design if water is available, having detailed spatial information on soil moisture is still a challenge. Earth Observation data have demonstrated to be a useful source of information to this purpose.

Scientific research on the retrieval of soil moisture from satellite sensors has a long history: it began with the availability of the first satellite images. Research has been done using different sensors, spanning different parts of the measured electromagnetic spectrum, and leading to several methodologies to estimate soil moisture content. All the algorithms developed are based on the inversion of models, of analytical or empirical nature, that relate the variables measured by satellite sensors to near-surface soil moisture. Depending on the sensor employed to image the Earth’s surface, different spatial and temporal resolutions can be achieved, thus the selection of the appropriate one will depend on the type of monitoring that is planned to be done.

The Sensors


The Global Environmental Satellite Observation Network

A brief survey of remote sensing sensors as well as their suitability in soil moisture retrieval will be presented hereafter. Multispectral sensors are remote sensing instruments that can acquire data in several bands of the optical and near infra-red part of the electromagnetic spectrum. The variable that is possible to measure with this type of instrument is the spectral reflectance, i.e. the ratio of energy reflected by the Earth to incident energy, in general coming from the sun. This quantity can be directly related to surface soil moisture. A major drawback of optical instruments is their dependence on atmospheric conditions and the need of the sun as a source of illumination.

Microwave sensors acquire measurements in the frequency range from 0.3 GHz to 300 GHZ i.e., a wavelength that spans from 1 m to 1 mm. There are two main types of such instruments: passive and active. Passive microwave sensors or radiometers measure the radiation emitted by the Earth’s surface in the field of view of the instrument. Over land, the emitted radiation is mainly dependent on soil temperature and its dielectric properties, the latter being directly influenced by the soil moisture. Although radiometers are not subject to the presence of the sun and the atmosphere has a little impact on the measured signal, the resolution of such instruments is in the order of several kilometres making them useful only for studies on the global scale.

Active microwave sensors or radars send out pulses of electromagnetic radiation and measure the amount that is backscattered in the direction of the antenna sensor. Having their own source of illumination, such sensors can acquire data night and day and in presence of cloud coverage. Data acquired by active microwave radars, such as scatterometers and Synthetic Aperture Radars (SAR), are also sensitive to changes in soil moisture among other parameters. Scatterometers, with a spatial resolution of several kilometers, have been used with success for studies on the global scale, while SAR, with a resolution that can reach a few meters, is suitable for studies at the local scale.

The choice of the type of sensor has to be done depending on the application. In case of water management for irrigation, the most suitable instrument is represented by SAR given its high resolution and night/day/all weather acquisition capabilities. The soil moisture maps generated from SAR data can be used by governmental agencies that manage water distribution or by the single farmer to schedule in a more efficient way the irrigation of their fields.

A practical application for irrigation water management

In the framework of a project led by Starlab [1], the different issues concerning the  operational retrieval of soil moisture using SAR images were investigated and tested over an area located in the north of Catalonia.

 The area of study (the red dots indicate fields sampled during the survey)

The area of study (the red dots indicate fields sampled during the survey)

The approach chosen for the retrieval of soil moisture is based on the calibration of a semi-empirical algorithm [2]. The calibration attempts at the optimization of the model in order to take into account the specificities of the vegetation cover in the area of interest.

Results were compared to ground measurements acquired during the several in-situ campaigns, showing that SAR data are able to estimate surface soil moisture with an accuracy that, depending on the type of vegetation cover, can vary between 5% and 10%.

Soil moisture map generated from an Envisat ASAR image covering the Catalonian area of Alt Empordà

Soil moisture map generated from an Envisat ASAR image covering the Catalonian area of Alt Empordà

Soil moisture maps generated from SAR data can be used to monitor the evolution of soil moisture on regional scale with high resolution. This is particularly interesting for applications such as water management for irrigation where the knowledge of the fine scale distribution of the soil water content would allow to precisely detect sensible areas. When the whole of the new Sentinel satellite constellation is launched and operative, the frequency of acquisition will be between one and three days over Europe and Canada.

Here in Starlab we are offering a soil moisture monitoring service based on the combined use of SAR images and in situ probes. The figure to the right shows an example of a soil moisture map generated using an image acquired by the ESA satellite ENVISAT with the ASAR sensor.

If you’d like to know more about how we use SAR data to monitor agriculture, please head over to the vegetation health product line for more information.

[1] Reppucci, A.; Moreno, L, “Near Surface Soil Moisture Estimation Using SAR Images: A Case Study in the Mediterranean Area of Catalonia”.In Proc. ESA Living planet symposium 2010, Bergen (Norway)
[2] : Loew, A., Ludwig, R.; Mauser, W. (2006). Derivation of surface soil moisture from ENVISAT ASAR Wide Swath and Image Mode data in agricultural areas. IEEE Trans. Geosci. Remote Sens., vol. 44, pp. 889-899.