Several members of the Global Ecosystem Dynamics Investigation (GEDI) science definition team, led by Ralph Dubayah, attended the Silvilaser Conference in October 2017 in Blacksburg, Virginia, U.S.A. The team provided a number of presentations related to GEDI to inform and update the attendees on the science strategies and to strengthen, renew and initiate scientific collaborations with scientists from all over the world. The Wednesday morning sessions especially were well-represented with presentations on the progress of GEDI-related science. Dr. Steven Hancock presented his work on the GEDI simulator; a simulator that can be used to generate GEDI-like lidar data and sampling pattern from different types of airborne and terrestrial lidar data. These GEDI-like simulations were used by Dr. Laura Duncanson to test different algorithms in order to estimate biomass from the lidar signals, supporting one of the GEDI’s core mission objectives: creating a global biomass product. Dr. John Armston informed the crowd about the different types of airborne and field information that have been crowd-sourced and processed for these GEDI-biomass calibration and validation efforts and elaborated on biomass products resulting from the AfriSAR campaign. The AfriSAR campaign was held in Gabon in 2016 as a collaboration between space agencies from different countries (NASA, ESA, DLR, ONERA, AGEOS) in preparation for multiple upcoming space missions, including GEDI. NASA flew the Land Vegetation and Ice Sensor (LVIS), the airborne predecessor of GEDI, in order to provide important calibration and validation data over dense tropical forests. Dr. Hao Tang presented the results of algorithms calculating indices describing the diversity of the foliage profile along the vertical vegetation profile applied to the LVIS data, in preparation for application to GEDI data. Suzanne Marselis (PhD candidate) presented her preliminary results towards an application of GEDI beyond the original mission statement; using airborne lidar data from the AfriSAR campaign to study transitions in vegetation structure between different ecosystems: the ecotone between savanna and tropical forest (see photo).
References to conference presentations:
Armston, J., Duncanson, L., Kellner, J., Marselis, S., Hancock, S., Tang, H., Hofton, M., Blair, B., Fatoyinbo, L., Dubayah, R. (2017). Calibration and validation of above ground biomass products from LVIS/GEDI: Results from the AfriSAR campaign. Silvilaser 2017, Blacksburg, Virginia, USA.
Duncanson, L., Armston, J., Hancock, S., Kellner, J., Marselis, S., Tang, H., Hofton, M., Goetz, S., Healey, S., Dubayah, R. (2017). Development of prediction strata for GEDI global above ground biomass modeling. Silvilaser 2017, Blacksburg, Virginia, USA.
Hancock, S., Armston, J., Tang, H., Duncanson, L., Hofton, M., Blair, J.B., Disney, M., Marselis, S., Kellner, J.R., Fatoyinbo, L., Dubayah, R. (2017). Bridging the gap between spaceborne, airborne and terrestrial lidar: The GEDI simulator. Silvilaser 2017, Blacksburg, Virginia, U
Marselis, S.M., Armston, J., Fitzpatrick, M., Dubayah, R. (2017). Characterization of vegetation structure at the tropical forest-savanna ecotone in Gabon. Silvilaser 2017, Blacksburg, Virginia, USA. (poster presentation).
Tang, H., Armston, J., Hancock, S., Marselis, S., Duncanson, L., Kellner, J., Jantz, P., Goetz, S., Hofton, M., Blair, B., Fatoyinbo, L., Dubayah, R. (2017). Pre-launch testing of GEDI canopy cover and vertical profile data product algorithms in African tropical rainforests. Silvilaser 2017, Blacksburg, Virginia, USA.
