Satellites are playing an important role in efficient management of water resources

Satellites are playing an important role in efficient management of water resources

17 April 2020

Building on the Sen-ET project led by DHI-GRAS, the European Space Agency (ESA) just published this news story featuring our state-of-the-art technology for deriving accurate measurements of evapotranspiration at parcel level. Our technology enables detection of water stress and irrigation support, at individual field scale, anywhere in the world. Currently, we are supporting irrigation management and precision agriculture activities in five continents.

Background

The Sentinel-2 and Sentinel-3 satellite constellations have highly suitable spatial, temporal and spectral characteristics for many agricultural applications. This includes estimating water evaporation from the soil and transpiration from the leaves (together called evapotranspiration – ET), the knowledge of which is critical for agricultural water resources management and water use optimization.

In order to robustly model ET, both optical and thermal satellite data are needed. The former data is acquired daily by Sentinel-3 at 300 m resolution and by Sentinel-2 every 3 to 5 days at 10 – 20 m resolution. Thermal data is acquired only by Sentinel-3 at around 1 km resolution. ET estimates derived directly from this thermal data would also have a resolution of “just” 1 km, which would obscure many agricultural landscape features.

This is why DHI GRAS together with IRTA and SANDHOLT worked on developing a method to fuse Sentinel-2 and Sentinel-3 data, with the aim of obtaining ET maps with a resolution of 20 m. This was the primary objective of the Sen-ET project.


Frontline technology for water resource management and irrigation support
One application where the Sentinel-based high-resolution actual evapotranspiration (ETa) estimates could be particularly useful is water rights monitoring and water accounting and auditing. Those tasks are sometimes performed at an irrigation district level, but often water use monitoring needs to be undertaken at an agricultural parcel level.

In those cases, the use of high-resolution data is essential. By relying on estimates of ETa, as opposed to potential or reference ET, it is possible to measure water consumption values in a more direct and robust manner. This is because ETa considers the actual water transfer from soil and vegetation into the atmosphere, while potential or reference ET are theoretical maximum values reflecting, respectively, water use of unstressed vegetation or atmospheric demand.

In the video at the bottom of the page we can observe the extra spatial detail which is revealed when using the Sen-ET methodology. At the native resolution of the Sentinel-3 thermal observations’, it is not possible to distinguish any agricultural fields or other landscape features, while at Sentinel-2 spatial resolution all the parcels are clearly visible. Focusing on the pivot irrigation fields in the top-left corner, with fine spatial resolution, we can easily separate both the total ETa of the different fields and the unique temporal pattern of each field (see figure below).

Those estimates can then be compared with either total rainfall values or with ETa of an un-irrigated area, close by, to calculate irrigation water input at parcel level. At coarse spatial resolution, the ETa estimate contains aggregated values from the adjacent fields as well as non-irrigated land in the vicinity of the fields, making such comparison more difficult.

The accuracy of the modeled ETa has been validated extensively in the Sen-ET project. The results indicate an uncertainty of around 30% in herbaceous agricultural fields, such as the irrigation pivot parcels. This number is a result of comparing instantaneous ETa estimates against 30-minutes eddy-covariance flux tower observations. The uncertainty in the flux-tower observations is usually in the order of 20% and this reflects on the satellite-based estimates’ accuracy. In addition, when aggregating the instantaneous estimates to daily, seasonal or yearly values the accuracy increases significantly as it cancels out random errors.

Application potential and way forward
Water is essential for life on Earth. Water is a critical natural resource that underpins all social and economic activities. Tools that can underpin further optimisation of water resource use and minimise consumption are instrumental in order to secure sustainable water resource management worldwide. Our cutting-edge methodology to derive reliable and timely ET estimations at field level provides a vital instrument to support informed decision making of critical water resources.

Our method provides critical information to support water use efficiency within several domains, including irrigation management, by providing an indicating of areas where crops experience water stress, as well as water licensing schemes by providing a cost-effective and efficient means to do water accounting.

The development of our state-of-the-art ET tool builds on several years of research led by Dr. Radoslaw Guzinski. Rado (PhD from the University of Copenhagen with a thesis focusing on remote sensing of evapotranspiration) is a Senior Remote Sensing Specialist and Software Engineer with DHI GRAS and was previously a Research Fellow with the European Space Agency (ESA). While at ESA he significantly contributed to the Mission Requirements Document for the proposed Copernicus High Spatio-Temporal Resolution Land Surface Temperature Mission.

For more information about our ET approach and ongoing work, please contact Rado at rmgu@dhigroup.com.

If you would like to know more about how our tool can be put into practice in your company, please reach out to our Business Development Manager, Torsten Bondo at tbon@dhigroup.com

Mapping the extent of the 2020 winter floodings in Denmark and France

DK4HAPS

Why is it important?

As a future technology, HAPS platforms will open a new market for remote sensing and surveillance by offering disruptive and complementary applications to services enabled by satellites, terrestrial infrastructures and Remotely Piloted Aircraft Systems (RPAS), at relatively low cost. This project will explore uptake potential among stakeholders in Denmark and identify potential use case applications in a Danish context.

Project highlights:

Analysing and documenting opportunities for HAPS platforms to contribute to, and strengthen, the capacity of the Danish authorities to carry out surveillance and monitoring tasks, primarily in the field of defense and security.

Documenting existing HAPS technology gaps, to uncover industry needs and requirements, in order to leverage opportunities for Danish tech companies to contribute relevant technology that can support the development of HAPS platforms.

Provision of tailormade workshops focusing on HAPS application potential and opportunities, to connect industry leaders and relevant stakeholders in the uptake community and explore relevant use case scenarios in Denmark.

In more detail..

High Altitude Pseudo Satellites (HAPS) are geostationary or quasi-stationary stratospheric platforms that provide a link between the capabilities of satellites, UAVs and aircrafts. Positioned in the lower stratosphere, at a height of just over 20 km, they are close enough to the earth to provide high spatial resolution video and image data and at a distance far enough to uncover large land and ocean areas, continuously and in near real time.

They are ideally positioned to complement and expand the capabilities of satellites in earth observation, telecommunications and navigation and provide time-critical and permanent monitoring and communication solutions at relatively low cost.

Therefore, in the near future, HAPS platforms are expected to open up a new market for remote monitoring, enabling a time-critical and satellite-like monitoring that can support and contribute to several state and private applications and surveillance missions in defense and security, including patrol in Arctic, ship and air traffic monitoring, border patrol, etc.

This project aims to define the specific need for HAPS-based monitoring solutions in Denmark and at the same time identify opportunities for Danish technology companies to contribute relevant technology that can support the development of HAPS solutions, including the development of miniaturized sensors and communication systems.

Center for Defence, Space & Security:

The Center for Defence, Space & Security (CenSec) is the prime Danish cluster for small and medium-sized enterprises specializing in high tech industries like defence, homeland security, space, aerospace, railway and maritime.

CenSec was founded in 2004 and established in 2007 as an industrial cluster. In 2018, CenSec was approved by the Danish Ministry of Higher Education and Science to also become a national Innovation Network for Security (Inno-Sec)

Earth Observation Centre of Excellence part of the DHI GROUP

info@dhigroup.com
+45 4516 9200

Agern Alle 5,
2970 Hørsholm,
Denmark

CVR: 36466871

Global Seas

Why is it important?

High-quality and reliable data on past, present and predicted conditions of various metocean parameters is essential in order to reduce fuel consumption, lower emissions and improve fleet management capacity in the shipping industry. DHI’s Global Seas will deliver hourly information on ocean current, wave and wind data one-year back and five days ahead in time, globally, through a series of accurate regional ocean current models assimilated by satellite data input.

Project highlights:

Providing global-local high-quality ocean surface current data achieved by combining earth observation and modelling techniques in a semi-automated downscaling approach

Covering a wide range of metocean parameters with expert assessment of quality and only including sufficiently reliable data.

Ensuring flexibility, easy and efficient access to the data exactly where the information is needed in the workflow of the end-users. This includes exploiting the increased bandwidth expected from sitcom and GPS positioning of vessels typically communicated via AIS.

In more detail..

Global Seas will deliver earth observation enriched high-quality data on ocean currents and other valuable metocean data tailored for application in the shipping sector with the purpose of making shipping more fuel efficient and ensure better management of the fleets.

The value creation will come from reduced fuel consumption, lower emissions and improved fleet management capacity. This is typically obtained by the shipping companies directly, by route optimization and fuel optimization service providers and by the vessel navigators and captains.The decisions made by the various players are complex on their own, but rely on the quality of past, present and predicted conditions of ocean currents, wind, waves, water level, sea temperature, salinity and other metocean conditions.

Global Seas focuses on generating value by providing easy and efficient access to current and other metocean high-quality data and estimating the accuracy of the data provided. This solution relies most heavily on altimetry-based sea surface height products combined with DHI’s world leading hydrodynamic models. Sea surface observations are used both for continually updating the tidal water level and current products, and it is the most important satellite observation for constraining mesoscale dynamics.

While emphasis is on ocean currents, the product will also integrate sea surface temperature (SST, from e.g. Sentinel 3A and 3B SLSTR), scatterometer surface wind speed data (from e.g. ASCAT, RapidScat), wave height and wind speed from altimetry

European Space Agency:

The European Space Agency (ESA) is the European space programme and its mission is to explore Earth, its immediate space environment, our Solar System and the Universe.

ESA also works closely with space organisations outside Europe to develop satellite-based technologies and services, and to promote European industries.

Earth Observation Centre of Excellence part of the DHI GROUP

info@dhigroup.com
+45 4516 9200

Agern Alle 5,
2970 Hørsholm,
Denmark

CVR: 36466871

Monitoring & Assessment of Climate Change Impact on Geomorphology in the Coastal Areas of Bangladesh

Why is it important?

The vulnerability of the coastal population in Bangladesh is on the rise due to climate change. In order to identify and adopt best practice measures to increase the resilience of the coastal population to natural disasters and climate change, it is critical to assess and understand the changes and dynamics of the coastal zone. This project aims to build sustainable capacity among technical staff as well as decision makers to utilize modern satellite-based techniques to monitor climate change challenges and to provide early warning in the coastal zone of Bangladesh

Project highlights:

Providing a detailed baseline of existing GIS and earth observation data handling capacities among key stakeholders in Bangladesh

Capacity building within the use of satellite imagery for effective, systematic and routinely monitoring of coastal areas in Bangladesh with a view to assess climate change impacts.

Provision of on-site tailormade technical workshops focusing on application of EO techniques and coupled local field surveys.

In more detail..

The project is intended to establish methodological guidelines and step-by-step workflows for Earth Observation based assessments of coastal zone dynamics in Bangladesh, and train staff in developing early warning capacity for bank erosion attacks, which is one of the most significant risks from climate change.

Furthermore, the EO based workflows will allow stakeholders to increase the general understanding of the morphological processes in the coastal zone of Bangladesh and the impacts of climate change on these processes.

The project will contribute significantly to develop the technical ability of key stakeholders within relevant government agencies in Bangladesh, to conduct time-critical analysis of erosion/accretion processes and assessments of climate change impacts using advanced remote sensing methods.

Long term linear regression - indicates areas that are getting wetter (blue) or drier (red)
Fractional water coverage

Climate Technology Centre and Network:

The Climate Technology Centre and Network (CTCN) is the operational arm of the UNFCCC Technology Mechanism, hosted by the UN Environment Programme and the UN Industrial Development Organization (UNIDO). The Centre promotes the accelerated transfer of environmentally sound technologies for low carbon and climate resilient development at the request of developing countries.

Earth Observation Centre of Excellence part of the DHI GROUP

info@dhigroup.com
+45 4516 9200

Agern Alle 5,
2970 Hørsholm,
Denmark

CVR: 36466871

A seesaw between climate extremes – Mapping the Australian flooding’s from space

A seesaw between climate extremes - Mapping the Australian flooding’s from space

12 FEBRUARY 2020

Just three weeks ago, we mapped the impacts of the devastating bushfires in Australia, triggered by the driest and hottest year on record. Heavy rainfall over the weekend has been a welcome relief for millions of animals and has helped to subdue some of the fires in New South Wales, however in return, the torrential rain has caused major flooding’s in the coastal regions.

Using our automated satellite-based operational flood mapping tool, we have mapped the extent of the flooding’s in one of the worst affected areas, around the city of Nowra in the Shoalhaven region, just south of Sydney. While the flood map quantifies the severity of the flooding’s, satellite images are also ideally positioned to visualize its effects on the overall water environment, as illustrated in the video.

So while the seesaw of events in Australia is a testimony to the unsustainable trajectory of our planet, we believe we are part of the solution – by bridging critical earth observation data and relevant stakeholders, we enable decision makers to take confirmative actions to respond to the severity of climate change and act upon climate impacts.

Our satellite-based product portfolio are ideally positioned to provide rapid and cost-efficient information about the impact of climate change and climate induced extreme events.

Quantifying the impact of the Australian bushfires from space

Quantifying the impact of the Australian bushfires from space

16 JANUARY 2020

This year’s fire season in Australia is widely regarded as one of the most severe on record, causing detrimental damage to natural landscapes, wildlife, cities and critical infrastructure across the nation. Using data from NASA's MODIS satellites, we have detected an accumulated quarter of a million km2 affected by active bushfires, during the last two months, more than the total land mass of the United Kingdom.

We are saddened by the ferocious bushfires sweeping across Australia and devoted to continuing to deliver our impactful tools and services to assist authorities in responding and scaling efficiently and effectively during such disaster scenarios. Our satellite-based product portfolio is ideally positioned to provide rapid and cost-efficient information about fire risk, impact and movement, thus offering critical tools for fire response. As an example, our high-resolution soil moisture product can be applied nationwide to conduct largescale assessments of fire risk.

Driven by our passion for change and curiosity about innovative and integrated satellite-based solutions, we continue to explore avenues to support decision makers in making critical evidence-based decisions.

Satellites and offshore wind farms

SATELLITE-BASED SOLUTIONS TO SUPPORT THE OFFSHORE WIND INDUSTRY:

20 december 2019

Offshore wind has experienced tremendous growth in recent years as an attractive and clean energy alternative. However rigorous environmental legislation and a harsh and dynamic environment require thorough and meticulous planning as well as continuous operational monitoring of windmill installations and the dynamics of the surrounding water bodies.

The majority of the data and information needed to plan, construct and operate offshore wind farms is costly, time consuming and risky to collect, requiring rigorous field campaigns and expensive equipment.

Cost-effective and reliable solutions from space

Satellite-derived data products and services provide a powerful, low cost and efficient alternative to supplement or replace traditional monitoring solutions, by delivering up to date insight on the dynamics of the seabed and conditions of the environment around offshore wind farms. Our key offerings include satellite-based approaches to map and monitor shallow water bathymetry; aquatic vegetation; geomorphological dynamics and sedimentary variations around offshore wind installations. We also provide critical input data components to support offshore wind cable landfall assessments, such as coastal dynamics, digital terrain models and imagery for site planning.

Satellite image showing sand bars around OWF Horns Rev in the North Sea. Using this type of image data, it is possible to monitor and estimate the seabed dynamics, in this case movement rates of the large scale sand waves. © DHI, contains Copernicus Sentinel data.
Rasmus Borgstrøm (second from the right) and Torston Bondo (Far right) at WindEurope 2019

Growing interest in satellite-based products among major stakeholders

We have experienced an increased uptake and interest in our products and services, by stakeholders involved in the offshore wind industry, which was most recently solidified at the WindEurope Offshore conference in Copenhagen last month. The conference is a leading platform for peer to peer discussions with industry leaders and specialists and a unique opportunity to grasp the latest industry trends. We were represented by our Managing Director, Rasmus Borgstrøm and Business Development Manager, Torsten Bondo and their discussions with peers, potential clients and collaborators indicates a significant continued interest in our Earth Observation products, designed to support the monitoring needs of offshore wind operators.

Continued engagement with offshore industry partners and clients in 2020

As we are approaching the end of 2019, we are reflecting on an upbeat year where we have been excited to experience this attention and acceptance of our products and services by clients in the offshore wind industry, and we are looking forward to 2020 where we will continue to push our reliable and low-cost tools to support offshore wind farm operations.

See the video to below for further information and insight on how our products match the needs of clients and stakeholders in the offshore wind industry.

Earth Observation Centre of Excellence part of the DHI GROUP

info@dhigroup.com
+45 4516 9200

Agern Alle 5,
2970 Hørsholm,
Denmark

CVR: 36466871

Mapping submerged aquatic vegetation

MAPPING SUBMERGED AQUATIC VEGETATION FROM SPACE:

18 DECEMBER 2019

Satellite based solutions to map and monitor the distribution of underwater vegetation dynamics in shallow water areas provides a cost-effective and efficient tool for consistent synoptic monitoring of large areas.

Delivering key insight on vegetation status and trends, satellite data provides a critical tool, enabling management authorities and decision-makers in making more effective decisions towards protecting and managing marine environments and resources.

Using high-resolution satellite data, novel machine learning techniques and advanced data processing, we have created the first-ever national overview of the spatial distribution of shallow-water submerged aquatic vegetation in Denmark.

The national map of submerged aquatic vegetation provides an important baseline on the current status of vegetation density in Danish territorial waters. Future efforts will aim to advance the baseline by making continuous assessments on year to year and intra annual variations in vegetation cover at national level.

With an established methodology and a scalable approach in place, satellite data can now be turned in to actionable data and information about the condition and status of submerged aquatic vegetation in shallow water areas, in any part of the world.

Thanks to the VELUX FOUNDATION for their generous grant, which has allowed us to reach this significant milestone.

Visit http://satlas.dk/marine-vegetation/ or click the button below to see the vegetation density map and learn more about satellite-derived aquatic vegetation mapping.

More information about coastal monitoring at DHI GRAS

Earth Observation Centre of Excellence part of the DHI GROUP

info@dhigroup.com
+45 4516 9200

Agern Alle 5,
2970 Hørsholm,
Denmark

CVR: 36466871

Presenting our satellite-based CAP monitoring solution at MARS 2019

Presenting our satellite-based CAP monitoring solution at MARS 2019

27 NOVEMBER 2019

DHI GRAS is excited to participate in the 25th annual MARS conference this week in Prague, Czech Republic. The conference provides a platform for EU member states to discuss lessons learned and approaches to administer the Integrated Administration and Control System (IACS) under EU’s Common Agricultural Policy (CAP).

Represented by Kenneth Grogan and Lotte Nyborg, we will present a novel satellite-based approach to underpin the monitoring framework of national paying agencies under CAP2020+. Our solution provides a streamlined and highly accurate monitoring system to check if farmers report correctly on crop types and farm management practices according to the rules, procedures and eligibility requirements under the framework of EU’s CAP policy. The monitoring system has been developed, tested and operationally implemented by the Danish Agricultural Agency (DAA) and provides a streamlined solution to assess farmers applications according to CAP requirements, while at the same time reducing the amount of time spent on control visits.

In brief, our solution consists of:

1) a powerful back-end image processing chain for handling petabytes of satellite data
2) an advanced analytics toolbox for machine learning, deep learning and time series analysis
3) a sleek front-end web viewer for easy presentation of results and reporting.

Operational services are tailored to CAP monitoring needs, including crop type mapping, grassland activity monitoring, detecting harvest and tillage, and monitoring of catch crops.

We have been excited about contributing to shape the new agricultural monitoring practices in Europe and we congratulate the DAA as first movers in the EU to adopt a satellite-based solution to administer CAP monitoring. With our solution we have proved that satellite-services offer a highly accurate and cost-efficient alternative to existing in situ monitoring options and we are excited about our corporation with the DAA, to develop a robust and accurate CAP monitoring system, optimized for local conditions in order to achieve very high accuracies. We will be looking forward to meeting with national authorities and EU policy makers this week in Prague, to discuss how other countries can tap into the services offered by the monitoring system developed for the Danish authorities.

More information about agricultural monitoring at DHI GRAS

Earth Observation Centre of Excellence part of the DHI GROUP

info@dhigroup.com
+45 4516 9200

Agern Alle 5,
2970 Hørsholm,
Denmark

CVR: 36466871