It is estimated that 80% of the world’s ancient forests have been destroyed or irreparably degraded, predominantly by human activity. The price for this destruction is escalating climate change, biodiversity loss, diminishing habitat for endemic species and community displacement. With land use and forests in the spotlight at the United Nations Climate Conference COP28, the contribution of data from satellites is more important than ever.
OpenSpace spoke to Klaus Scipal, the European Space Agency’s (ESA’s) Mission Manager for Biomass, to understand how the Biomass satellite, due to launch in 2025, will provide critical information to researchers and governments to help protect and expand our remaining forests.
The world’s ancient forests are critical ecosystems for fighting climate change, supporting livelihoods and protecting biodiversity. Forests across the globe are being destroyed every day by industrial scale logging operations, many of which are illegal, as well as land grabbers chopping trees for palm oil manufacturing and clearing ground for illegal mining and livestock farming.
According to recent data from the University of Maryland on the World Resources Institute Global Forest Watch platform1, in 2022 the Tropics lost an estimated 4.1 million hectares of primary rainforest: the equivalent of 11 football fields of forest every minute, and 10% more primary rainforest than was lost in 2021. All this forest loss produced 2.7 gigatonnes of carbon dioxide emissions, which is equivalent to India’s annual fossil fuel emissions.
The destruction of these forests is pushing many indigenous species – such as the orangutan in Malaysia and the jaguar and tapir in the Amazon Basin – towards the brink of extinction, as well as devastating local communities. It is estimated that 1.6 billion people, including nearly 70 million indigenous people, rely on forest resources for their livelihoods. Deforestation, especially in the Tropics, impacts local temperatures and rainfall in ways that can compound the effects of global climate change, with consequences for human health and agricultural productivity.
Why do forests matter?
We know that humankind is facing a ‘final warning’ on the climate crisis, and that reducing deforestation is one of the most cost-effective and important land-based measures we can implement to mitigate climate change. Forests are both a source and a sink for carbon, removing carbon dioxide from the air when standing or regrowing and emitting it when cleared or degraded.
In addition to exacerbating global warming, scientists have warned that deforestation heightens the risk of global pandemics. It is suggested that deforestation and forest degradation may have played a critical role in triggering the COVID-19 pandemic. According to a study in Nature2, the populations of animals hosting zoonotic diseases, like the coronavirus, are up to 2.5 times higher in degraded places.
How is space helping?
Space is playing a major role in helping to identify and tackle deforestation. Satellites have been used for decades to monitor the loss of ancient forests using space-based technologies, helping inform and provide researchers, governments, farmers and industry with the information they need to act more effectively in tackling this crisis.
Many satellites have been launched by ESA, NASA, national agencies and commercial operators to look at different aspects of our Earth. For example, the European Copernicus programme includes Sentinel-1: a pair of satellites that each carry a synthetic aperture radar (SAR) instrument to provide all-weather, day-and-night imagery of the Earth’s surface, thus providing historical information on forest locations. Sentinel-2 also consists of two identical satellites that deliver high-resolution imagery with 13 spectral bands to give an overview of land and vegetation variants.
A UK Government survey found that monitoring illegal logging with satellites could be up to 12 times more cost effective than traditional measures3. Satellite technology offers near real-time monitoring of large-scale illegal deforestation operations. This allows for the kind of rapid response capability that the fight against global deforestation desperately needs, and enables pressure and policy to be applied in a targeted and more effective and efficient manner.
Introducing Biomass
Existing satellites have provided data to show how forests have diminished over time. However, none of their instruments can penetrate the forest canopies to give us a true understanding of the health and biomass of the tropical forests. To address this, ESA will soon launch an innovative new satellite called Biomass, as part of the Earth Explorer programme, that will provide crucial information about the state of forests and further our knowledge of the role forests play in the carbon cycle.
ESA’s Mission Manager for Biomass and SMOS, Klaus Scipal, advises: “The Biomass satellite is a scientific mission looking at the Earth in a way that no one else has looked at it before. We want to answer new science questions and Biomass will contribute to what we know least and fill the biggest knowledge gaps. By taking observations and measuring forest structure and how it changes over time, Biomass will help us to better understand the role forests play in the carbon cycle, especially tropical forests, which are the most diverse and important ones in this respect in the world.
“Observations from Biomass will lead to better insight into the rate of habitat loss and the impact this may be having on biodiversity in the forest environment. In addition, the mission will offer the opportunity to map subsurface geology in deserts, the ice structure of ice sheets and the topography of forest floors.”
Monitoring the carbon cycle
“Forests play a very important role in climate change and they do this in two ways. Fifty percent of a tree is carbon; if you cut down the tree or if it burns, all that carbon is moved into the atmosphere and contributes to global warming. At the same time, trees soak up a tremendous amount of carbon from the atmosphere. They are so effective that they are one of the main mitigation aspects in the fight against climate change.”
Forests are estimated to absorb around 8 gigatonnes of atmospheric carbon dioxide every year, playing a crucial role in the carbon cycle and climate system. However, forest degradation is causing much of this stored carbon to be released back into the atmosphere, exacerbating climate change.
What is special about Biomass?
“Biomass is the first ever satellite to use P-band SAR instruments that will measure radar signals emitted by the satellite and reflected back from the Earth. P-band sensors use a very long wavelength, about 60cm in the case of Biomass. The longer your wavelength is, the better you can penetrate something – in this case forest canopies. With Biomass we will be able to penetrate deep into the vegetation and the signal we receive will have been scattered back from all the elements within the vegetation. It will be very sensitive to tree trunks, branches etc.; in very simplified terms, the more of the structure you see, the more signal you will get back. This allows us to get an indirect measurement that we can then convert into biomass measurements.
“Measurements of forest biomass can be used as a proxy for stored carbon, which will reduce the major uncertainties in calculations of carbon stocks and fluxes on land, including carbon fluxes associated with land use change, forest degradation and forest regrowth.”
Data usage
“Biomass will help researchers quantify the global carbon cycle, which is essential to understanding the rapid changes that forests are undergoing and the subsequent implications for our climate. Measurements of forest biomass can be used as a proxy for stored carbon – but this is currently poorly quantified for the majority of forests around the world. Data from the Biomass mission will reduce major uncertainties in calculations of carbon stocks and fluxes on land, including carbon fluxes associated with land use change, forest degradation and forest regrowth.”
The main users for the information gained from Biomass will be the scientific community, especially those studying forest ecology and the carbon cycle. The data will also contribute to societal needs. Governments have agreed to take action against climate change and deforestation and give financial incentives to developing countries. Biomass will provide essential data to see if these actions are effective.
1. wri.org/initiatives/global-forest-watch
2. Nature; Zoonotic host diversity increases in human-dominated ecosystems; August 2020
3. UK Space Agency; International Partnership Programme: A Summary of the IPP Midline Evaluation; August 2020
