Biomass mission – measuring Earth's 'lung capacity' from space
- The ESA Biomass mission is scheduled to launch on 29 April 2025, enabling the precise determination of global forest biomass for the first time.
- Germany is participating with more than 20 percent of the mission's overall funding as well as providing the main instrument, with contributions being coordinated by the German Space Agency at DLR.
- The DLR Microwaves and Radar Institute has conducted preliminary airborne measurement campaigns to develop algorithms for estimating forest biomass, has developed a prototype radar data processor and created the software simulator for the German radar instrument.
- Focus: Space, Earth observation, climate change
Forests cover 40.6 million square kilometres of our planet – almost a third of Earth' s ice-free land area. Often called the 'green lungs' of our planet, they supply our atmosphere with fresh oxygen. But how healthy is this vital organ of our Earth? Can it continue supplying us with enough fresh air to keep Earth's ecosystems functioning? To answer these questions, we must first determine the lung capacity of our forests. This is the task of the Biomass mission, which is scheduled to launch on 29 April 2025 on a Vega-C rocket from Europe's Spaceport in Kourou, French Guiana. “Forests are the green lungs of our planet," says Walther Pelzer, Executive Board Member of the German Aerospace Center (Deutsches Zentrum für Luft- und Raumfahrt; DLR) and Director General of the German Space Agency at DLR. "So far, however, we have only been able to estimate the amount of forest biomass worldwide. The European Biomass mission will, for the first time, determine the volume of this important carbon store with unprecedented precision and provide a detailed picture of the health of our forests – an essential step to accurately calculate global warming, predict the consequences of climate change and take effective countermeasures. At the heart of this mission is a radar instrument developed and manufactured in Germany – further proof of our global leadership in radar technology."
German-made 'lung capacity detector' measures biomass and carbon
Biomass is the seventh Earth Explorer mission in the European Space Agency's (ESA) FutureEO programme, which aims to pave the way for new technologies in operational Earth observation. Germany is contributing approximately 20 percent to the mission's budget, coordinated by the German Space Agency at DLR. The centrepiece is the German-developed P-Band synthetic aperture radar (SAR) instrument. This radar system will accurately measure forest biomass volumes as well as the amount and distribution of carbon stored in forests. This radar instrument will ensure that Biomass can deliver global maps of forest biomass and tree height every seven months – essential information for international climate agreements. The mission supports goals outlined in Germany's Space Strategy in the context of the United Nations' 2030 Agenda, the European Union's Green Deal, the Paris Climate Agreement and other global commitments.
This 'lung capacity detector' was developed by Airbus Defence and Space in Friedrichshafen. The DLR Microwaves and Radar Institute in Oberpfaffenhofen conducted various preliminary airborne measurement campaigns, developed the prototype radar data processor and will support the calibration and validation phase after launch.
Research flights pave the way for highly accurate measurements
"Earth's forests are vital to the climate, biodiversity and not least the future of humanity," explains Konstantinos Papathanassiou from the DLR Microwaves and Radar Institute. "As such, it is crucial that we not only assess their current state but also use it to project their future. This is far from easy, as forests today are under enormous strain from deforestation, fires and climate change. These threats have a dramatic impact on their role as ecosystems and carbon stores and have devastating consequences for their biodiversity. Biomass will be the first mission to determine the 3D structure of forests and thus reveal the spatial distribution of their biomass, as well as capturing their complexity and diversity. This will allow us to assess the current state of forests and make predictions about their future development. The methods for this were developed by European scientists with significant DLR involvement."
As the first satellite-based mission to operate in the P-band frequency range, Biomass had to overcome a number of scientific and technical challenges. P-band radar penetrates dense vegetation and is particularly sensitive to structures such as tree trunks and large branches. The DLR Microwaves and Radar Institute played a key role from the outset, providing support throughout all mission and selection phases with its extensive expertise in SAR technology. Scientifically, the Institute is responsible for defining, generating and validating data products related to forest height and changes over time. Flight campaigns using DLR's airborne radar system helped scientists prepare for the Biomass mission and were crucial for developing and validating algorithms used to generate the geophysical products, including two flight campaigns in Gabon. During these measurement campaigns, the DLR Institute collected tomographic datasets. DLR's Dornier DO 228-212 research aircraft, operated by the Flight Experiments facility in Oberpfaffenhofen, was used for the measurement flights. The campaigns were led by DLR and carried out in collaboration with ESA.
Trees – Earth's colossal carbon stores
Trees store large amounts of carbon by absorbing carbon dioxide (CO2) during photosynthesis and turning it into wood. The soils of intact and near-natural forests, moors and wetlands also store a vast quantity of carbon. Rainforests in particular are among the largest carbon dioxide reservoirs on Earth. Scientific estimates indicate that approximately 18 million square kilometres of rainforest remain worldwide – more than 50 times the size of Germany. This includes approximately 13.4 million square kilometres of tropical rainforest, the largest of which is the Amazon rainforest at around seven to eight million square kilometres. For comparison, the entire European Union covers an area of only about 4.2 million square kilometres – roughly half as large. When carbon dioxide is suddenly released in large quantities due to deforestation or fires, it has a dramatic impact on the climate. The Biomass mission will provide important information about forest resources, ecosystem services, biodiversity and nature conservation – not only for rainforests but also boreal forests. However, use of the collected data goes far beyond monitoring forests. The treasure trove of data will also assist in monitoring the ionosphere, glaciers and ice sheets, as well as the detection of subterranean geological structures in desert regions and the topography of surfaces hidden beneath dense vegetation.
Biomass – a European mission with strong German involvement
Germany's contribution to the Biomass mission exceeds 20 percent of its total budget and includes the provision of its main instrument. These activities are coordinated by the German Space Agency at DLR. The DLR Microwaves and Radar Institute has conducted preliminary test campaigns for the mission and developed the prototype data processor and software simulator for the radar system. In addition, Germany is responsible for key technological work packages, in particular with Airbus Defence and Space – strengthening the company's radar expertise – as well as through numerous small and medium-sized enterprises. Airbus Defence and Space was responsible for the development of the radar instrument (excluding the reflector), the central electronics and also participated in developing the solar sail. DSI GmbH built the Payload Data Handling Unit, while OHB System AG was involved in developing the platform structure and Ariane Group contributed to the propulsion system. TESAT Spacecom GmbH built the X-band and S-band communication systems and, together with United Monolithic Semiconductors, developed the central GaN transistor for power-efficient amplification – to be used in space for the first time. The Center of Applied Space Technology and Microgravity (ZARM) in Bremen built the magnetic torquer, while Rockwell Collins provided the reaction wheels. Other contributors include HPS GmbH, SpaceTech GmbH and RST Rostock.
To coordinate the scientific use of the mission, the Project Office Biomass was established at the Max Planck Institute for Biogeochemistry in Jena, on behalf of the German Space Agency at DLR.