The ESA BIOMASS and “4th”missions: relation to GFOI S. Quegan, University of Sheffield & NCEO

Scope of talk What is the role of BIOMASS in Global Forest Observing System? How does it fit relative to other missions? What can BIOMASS do for GFOI? What can do GFOI for BIOMASS?

Biomass is the 7th ESA Earth Explorer mission Core Missions Opportunity Missions 2021 BIOMASS Forest Biomass 3

Measuring height needs repeat visits and polarisation 07/22/12 Measuring height needs repeat visits and polarisation Orbit cycle n Orbit cycle n+1 Calibration, Ionospheric correction Polarimetry HH HV VV Phasedifferences Polarimetry + Interferometry Retrieval algorithm The need to map biomass drives us immediately towards radar. Optical sensors see biochemistry, radar sensitive to structure. What sort of radar? Polarimetry (figs on R) Repeat pass for interferometry Both critical as we can see Forest biomass Forest height Forest disturbance 4

Key system constraints BIOMASS is only allotted a 6 MHz bandwidth by the ITU a ground-range resolution of ~55m in range. Accurate estimates of backscatter rely on speckle reduction usable resolution is significantly reduced. Global coverage of forested areas subject to Space Object Tracking Radar restrictions. 1 global map in first 14 months, then new maps every 7 months within 5 year mission lifetime. Forest AGB Forest height Deforestation Resolution 200 m 50 - 60 m Accuracy 20% or 10 t/ha for AGB < 50 t/ha 20 - 30% Classification accuracy of 90%

Large biomass uncertainty Space Object Tracking Radar constraints limit the possible in situ training sites Land use change Land use change reforestation fire & climate warming drought pests regrowth Reducing Emissions from Deforestation & Degradation (REDD) Global Forest Observations Initiative Tropics and Asia have limited inventory systems, incomplete data, high biomass and ongoing LUC. Climate change, including warming and drought may have impacts in tropical and boreal zones. Reforestation is occurring in China at high rates. Global Forest Observations Initiative and REDD areas are located in the tropics Be prepared to mention SOTR Large biomass uncertainty

BIOMASS will not be alone in space Forest structure & lower level biomass Forest biomass & height BIOMASS ESA’s 7th Earth Explorer The “4th mission”; in situ networks Forest structure & biomass

Training and validation: the “4th mission” In situ network led by Smithsonian, including Centre for Tropical Forest Science Rainfor Afritron

Training and validation sites in the tropics The good news: Ecological analysis suggests only ~50 supersites are needed to cover the range of tropical forest types. The bad news: Establishing all these sites would cost ~$20M. But it seems likely that 50 ecological forest types map into < 50 different P-band radar signatures.

Biomass in GFOI GFOI is very much based on IPCC principles; practical methods that can be implemented at country level and “as far as possible” yield unbiased estimates of forest change and the associated emissions In the GFOI MGD Earth Observation forms a core element in estimating forest area change. This needs to be converted into emissions and uptake using emissions factors at different levels of complexity The parameters needed to make this conversion are essentially based on in situ data. Change in biomass is a fundamental quantity in quantifying emissions and uptake.

The potential benefit of BIOMASS to GFOI Can BIOMASS (and other forest missions) supplant or supplement in situ methods? How do we develop a strategy to use BIOMASS (and other forest mission) data within the county-based carbon flux estimates accepted by IPCC?

The potential benefit of GFOI to BIOMASS Countries involved in GFOI are developing forest inventories, often supplemented by extensive lidar surveys. These could be extremely helpful in helping to train and validate biomass estimates from space if they meet suitable quality standards. How do we develop a dialogue with GFOI and its participating countries to promote this? Overall key issues for the UK: How do we fit space EO missions, especially BIOMASS, in the developing framework of GFOI and its research programme? How do ensure that the almost unrivalled UK expertise in tropical forest networks is effectively exploited by GFOI?

Overall key issues for the UK How do we fit space EO missions, especially BIOMASS, in the developing framework of GFOI and its research programme? How do ensure that the almost unrivalled UK expertise in tropical forest networks is effectively exploited by GFOI?