BRIX is a first international collaborative initiative to inter-compare a set of biomass retrieval algorithms for P-band full-polarimetric SAR sensors. The exercise will focus on airborne campaign data acquired in the context of the preparation of the BIOMASS mission. The inter-comparison of biomass retrieval algorithms is expected to contribute to the understanding of the different uncertainty contributors and help in improving the biomass retrieval from P-band full-polarimetric SAR data.
Selected as ESA's seventh Earth Explorer in May 2013, the BIOMASS mission will provide crucial information about the state of our forests and how they are changing. The data will be used to improve our understanding of the role of forests in the global carbon cycle. To prepare for the mission, several groups have started to develop Above Ground Biomass (AGB) retrieval algorithms based on P-band full-polarimetric, interferometric airborne SAR data acquired in recent campaigns. To support these activities and to bring together the groups involved in this endeavour ESA organizes BRIX, an exercise to inter-compare and learn from different biomass retrieval algorithms. The results of the exercise are expected to point out the strengths and weaknesses, as well as communalities and discrepancies of the various ideas to retrieve biomass . in order to suggest and define ways for their further improvement.
Objectives and Expected Outcomes
The exercise aims at bringing together scientists working on the development of biomass retrieval algorithms and to invite them to generate AGB products under well-defined conditions. The input data will be a set of P-band full-polarimetric airborne SAR data of various test sites of tropical forest over Gabon from the recently flown ESA AfriSAR campaign. A common and harmonised inter-comparison procedure will be agreed and followed by all the participants.
The BRIX Objectives are:
The objectives shall be achieved by making available standardised test cases (based on campaign data), inviting the scientific community to develop and apply retrieval algorithms based on this test case, and finally compare, evaluate and discuss the submitted results.
The BIOMASS Level-2 Algorithms Test Bed
For the purpose of an objective algorithm evaluation ESA has set up the BIOMASS Level-2 Algorithm Test Bed. This test bed is a virtual machine run that:
Participants will be invited to upload their code to the test bed (or develop it on the test bed) and run it on the test bed using the predefined campaign datasets.
This Test Bed shall not only facilitate the inter-comparison of different algorithms but also facilitate sharing code and ideas and foster the discussion between the participating groups.
Schedule and Deadline
After the registration deadline, ESA will grant all participants access to the test bed.
Then, the Biomass Retrieval Algorithm Inter-comparison Exercise will be performed in three phases:
In the framework of the exercise, a Workshops will be held: