Mapping Global Live Woody Vegetation Biomass at Optimum Spatial Resolutions
Creators: name: Sassan Saatchi
Publisher: name: Zenodo
Year: 2023
Subjects: Forest, Biomass, Satellite Imagery, Forest Height, Disturbance, Recovery

description: <strong>Mapping Global Live Woody Vegetation Biomass at </strong> <strong>Optimum Spatial Resolutions</strong> Yifan Yu<sup>1</sup>, Sassan Saatchi<sup>1,2</sup>, Yan Yang<sup>1,2</sup>, Liang Xu<sup>1</sup>, Victoria Meyer<sup>1</sup>, Esteban Álvarez-Dávila<sup>3</sup> , Valerio Avitabile<sup>4</sup>, André Beaudoin<sup>5</sup>, Georges Boundzanga<sup>6</sup> , Matt Bradford<sup>7</sup>, Jerome Chave<sup>8</sup>, David Clark<sup>9</sup>, Matoko K. Dabney<sup>10</sup>, Stuart J. Davies<sup>11</sup>, Grant Domke<sup>12</sup>, Alvaro Duque<sup>13</sup>, William Farfan-Rios<sup>14</sup>, Antonio Ferraz<sup>2</sup>, Alexander Fore<sup>1</sup>, Sangram Ganguly<sup>15</sup>, Mariano García<sup>16</sup>, Nancy Harris<sup>17</sup>, Martin Herold<sup>18</sup>, Michael Keller<sup>19</sup>, Nicolas Labrière<sup>8</sup>, Michael Lefsky<sup>20</sup>, Renato A.F. de Lima<sup>21</sup>, Destin Loge Lokegna<sup>11</sup>, Marcos Longo<sup>1</sup>, Richard Lucas<sup>22</sup>, Ronald McRoberts<sup>23</sup>, Manchiraju Murthy<sup>24</sup>, Erik Næsset<sup>25</sup>, Ramakrishna Nemani<sup>16</sup>, Jean Ometto<sup>26</sup>, John Poulsen<sup>27</sup>, Jon Ranson<sup>28</sup>, Juan Saldarriaga<sup>29</sup>, Aurelie Shapiro<sup>30</sup>, Herman Shugart<sup>31</sup>, Miles Silman<sup>14</sup>, Ferry Slik<sup>32</sup>, Guoqing Sun<sup>33</sup>, Rajesh B. Thapa<sup>34</sup>, Alexander Vibrans<sup>35</sup>, Lee White<sup>36</sup> Christopher Woodall<sup>37</sup>, Ulrike Seibt<sup>38</sup> <em><sup>1</sup>Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA<br> <sup>2 </sup>Institute of Environment and Sustainability, University of California, Los Angeles, CA, USA</em> <em><sup>3</sup>Escuela de Ciencias Agrícolas, Pecuarias y del Medio Ambiente, National Open University and Distance, Bogotá, Colombia</em> <em><sup>4</sup></em><em>European Commission, Joint Research Centre<strong>, </strong>21027 Ispra (VA), Italy</em> <em><sup>5</sup></em><em>Centre de foresterie des Laurentides / Laurentian Forestry Centre, </em><em>Québec (Québec) G1V 4C7 </em> <em><sup>6</sup>CN-REDD, Brazzaville, République du Congo</em> <em><sup>7</sup>Commonwealth Scientific and Industrial Research, Organization (CSIRO) Land and Water, Tropical Forest Research Centre, Atherton, Australia;</em> <em><sup>8</sup>CNRS Unité Evolution et Diversité Biologique, Université Paul Sabatier, 31062 Toulouse, France</em> <em><sup>9</sup>Department of Biology, University of Missouri-St. Louis, St. Louis, Missouri 63121 USA</em> <em><sup>10</sup>Ministère de l’Economie Forestière, Centre National d’Inventaire et Aménagement des Forêts (CNIAF) of the Republic of Congo</em> <em><sup>11</sup>Forest Global Earth Observatory, Smithsonian Tropical Research Institute, PO Box 37012, Washington, DC 20013, USA</em> <em><sup>12</sup>US Department of Agriculture, Forest Service, St. Paul MN, USA</em> <em><sup>13</sup>Socioecosistemas y Cambio Climatico, Fundacion con Vida, Medellín, Colombia.</em> <em><sup>14</sup>Department of Biology, Wake Forest University, Winston-Salem, NC USA</em> <em><sup>15</sup>NASA Ames Research Center, Moffett Field, California, CA</em> <em><sup>16</sup>Department of Geology, Geography and Environment, University of Alcalá, Madrid, Spain</em> <em><sup>17</sup>Research Director, Forest Program, World Resources Institute, Washington DC, USA</em> <em><sup>18</sup>Laboratory of Geo‐Information Science and Remote Sensing, Wageningen University and Research, Wageningen, The Netherlands</em> <em><sup>19</sup>USDA Forest Service, International Institute of Tropical Forestry, San Juan Puerto Rico, USA</em> <em><sup>20</sup>Department of Ecosystem Science and Sustainability, Colorado State University, Fort Collins, USA</em> <em><sup>21</sup> Departmento de Ecologia, Instituto de Biociências, Universidade de São Paulo, Rua do Matão, nº 321, 05508-090, São Paulo, SP, Brazil</em> <em><sup>22</sup>Centre for Ecosystem Science, The University of New South Wales, Sydney, Australia </em> <em><sup>23</sup>Department of Forest Resources, University of Minnesota, Saint Paul, Minnesota, USA</em> <em><sup>24</sup>International Centre for Integrated Mountain Development. GPO Box 3226, Kathmandu, Nepal.</em> <em><sup>25</sup>Faculty of Environmental Sciences and Natural Resource Management, Norwegian University of Life Sciences, NMBU, Norway</em> <em><sup>26</sup>Earth System Science Centre (CCST), National Institute for Space Research (INPE), José dos Campos, SP, Brazil</em> <em><sup>27</sup>Nicholas School of the Environment, Duke University,Durham, NC U.S.A</em> <em><sup>28</sup>NASA GSFC, Biospheric Sciences Laboratory, Greenbelt, MD, USA</em> <em><sup>29</sup>Carrera 5 No 14-05, Cundinamarca, Colombia</em> <em><sup>30</sup>World Wide Fund for Nature(WWF) Germany Biodiversity Unit, Berlin, Germany</em> <em><sup>31</sup>Department of Environmental Sciences, University of Virginia, Charlottesville, Virginia, USA</em> <em><sup>32</sup>Faculty of Science, Universiti Brunei Darussalam, Gadong, Brunei</em> <em><sup>33</sup>Department of Geographical Sciences, University of Maryland, College Park, MD, USA</em> <em><sup>34</sup>International Centre for Integrated Mountain Development, Khumaltar, Lalitpur, Kathmandu, Nepal</em> <em><sup>35</sup>Universidade Regional de Blumenau – Depto. de Engenharia Florestal, R. São Paulo, SC – Brasil.</em> <em><sup>36</sup>Agence Nationale des Parcs Nationaux, Libreville, Gabon, Ministère de la Forêt, de la Mer, de l'Environnement, Chargé du Plan Climat, Libreville, Gabon.</em> <em><sup>37</sup>United States Forest Service, Northern Research Station–Durham, Durham, NH, USA.</em> <em><sup>38</sup>Department of Atmospheric and Oceanic Sciences, University of California, Los Angeles, California, USA</em> Classification: Physical sciences, environmental sciences Keywords: forest biomass, forest height, carbon cycle, microwave and optical imaging, error propagation, maximum entropy Corresponding Author: Sassan Saatchi Jet Propulsion Laboratory California Institute of Technology 4800 Oak Grove Drive Pasadena, CA 91109 Email: Saatchi@jpl.nasa.gov Tel: +1-818-354-1051 <strong>Abstract</strong> Carbon emissions from forest disturbance are estimated by the area of disturbance multiplied by the emission factors. The area of disturbance is routinely quantified by high-resolution satellite observations, while emission factors are inferred from forest inventory data at national or global scales. This discrepancy between the scale of disturbance and emission factors is hypothesized to introduce large bias in estimates of annual carbon emissions. To test the hypothesis, we used the 30-m global forest cover change to show that on average 80% of disturbances are less than 10-ha in size and 75% of the time occur within 1-km of past disturbances; together pointing to the optimum scale for quantifying emission factors. Using systematic inventory of forest structure from ground, air, and space and satellite imagery, we map global vegetation live biomass at 100-m spatial resolution (1-ha) with a combined model-based and spatial machine learning estimators. We found large spatial heterogeneity of carbon storage at 1-ha scale related to impacts of disturbance and recovery processes and natural edaphic variations amounting to 428±64 PgC (341±51 PgC above, 87±13 PgC below) partitioned into 328 PgC in forests and 100 PgC in savannas and shrublands. We verified the hypothesis by showing that there was up to 30% bias from underestimating emissions when the scale of emission factors increased and the bias varied geographically with forest types and disturbance regimes. Our results show that fine-scale mapping of biomass carbon density is essential in reducing the uncertainty of carbon emissions and removals from terrestrial ecosystems.