1- 1Faculty of Environment, Science and Economy, University of Exeter, Exeter, United Kingdom, T.Rosan@exeter.ac.uk
- *A full list of authors appears at the end of the abstract
Since the 1950s, the rapidly rising atmospheric greenhouse gas (GHG) concentrations have driven anthropogenic climate change, with terrestrial ecosystems acting as both sources and sinks of carbon. While global syntheses provide crucial benchmarks, regional assessments are essential to understand the fine-scale interactions between land-use, climate variability, and carbon fluxes. Motivated by this need, the Regional Carbon Cycle Assessment and Processes- Phase 2 (RECCAP2) initiative aims to deliver updated GHG budgets across (sub-) continental scales. Here, we focus on South America, a continent of critical importance to the global carbon cycle due to its extensive tropical forests, particularly the Amazon Forest. This is also important to the methane cycle due to the large wetland areas in the region.
Quantifying the regional carbon budget is challenging because it emerges from the net balance of large opposing fluxes: high productivity and long carbon residence times in old-growth forests act as a sink, while deforestation, degradation, and human-induced fires contribute to a source. Climate variability, including the El Niño-Southern Oscillation and Atlantic-Pacific sea surface temperature anomalies, modulates interannual and decadal fluxes, influencing droughts, fire risk, and forest stability. The interactions of land-use change, climate extremes, and fire introduce substantial uncertainty in current budget estimates.
Using a combination of dynamic global vegetation models, atmospheric inversions, and regional observational datasets, we quantify the terrestrial carbon balance of South America at continental, national, and Amazon basin scales, for the period 2010-2019, and assess recent trends (i.e., 2020–2024) in key components, including land-use and land-cover change (LULUCF) and fire emissions. Preliminary results reveal spatially heterogeneous contributions to the continental carbon sink and highlight regions where disturbances and climate extremes are driving shifts in the net flux towards a carbon source. To provide a more comprehensive overview of the dynamics in this region, we also examine methane fluxes during this period and investigate potential recent trends. Our findings will provide a benchmark for regional greenhouse gas budgets, improve attribution to processes, and inform climate mitigation strategies in South America.
Luana S. Basso (Department of Biogeochemical Signals, Max Planck Institute for Biogeochemistry, Jena, Germany); Santiago Botía (Department of Biogeochemical Signals, Max Planck Institute for Biogeochemistry, Jena, Germany); Michael O’Sullivan (Faculty of Environment, Science and Economy, University of Exeter, Exeter, UK); Stephen Sitch (Faculty of Environment, Science and Economy, University of Exeter, Exeter, UK); Barbara Zimbres (Instituto de Pesquisa Ambiental da Amazônia – IPAM, Brasília, Federal District, Brazil); Chris Wilson (National Centre for Earth Observation, University of Leeds, Leeds, UK; School of Earth and Environment, University of Leeds, Leeds, UK); Ronny Lauerwald (Université Paris-Saclay, INRAe/AgroParisTech, UMR EcoSys, Palaiseau, France); Auke van der Woude (Environmental Sciences Group, Dept of Meteorology and Air Quality, Wageningen University, Wageningen, The Netherlands); Ingrid T. Luijkx (Environmental Sciences Group, Dept of Meteorology and Air Quality, Wageningen University, Wageningen, The Netherlands); Wouter Peters (Wageningen University, Environmental Sciences Group, Wageningen, The Netherlands; University of Groningen, Centre for Isotope Research, Groningen, The Netherlands); Ben Poulter (Spark Climate Solutions, San Francisco, CA, USA); James D. East (School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA); Judith Rosentreter (Faculty of Science and Engineering, Southern Cross University, Lismore, Australia); Philippe Ciais (Laboratoire des Sciences du Climat et de l’Environnement, LSCE/IPSL, CEA-CNRS-UVSQ, Université Paris-Saclay, Gif-sur-Yvette, France); Yidi Xu (Laboratoire des Sciences du Climat et de l’Environnement, LSCE/IPSL, CEA-CNRS-UVSQ, Université Paris-Saclay, Gif-sur-Yvette, France); Athur Fendrich (European Commission, Joint Research Centre – JRC, Ispra, Italy); Zhu Deng (Department of Geography, The University of Hong Kong, Hong Kong SAR, China); Luiz Aragao (National Institute for Space Research – INPE, São José dos Campos, Brazil); Ana Bastos (Institute for Earth System Science and Remote Sensing, Leipzig University, Leipzig, Germany); Yohanna Villalobos (Department of Physical Geography and Ecosystem Science, Lund University, Lund, Sweden); Viola Heinrich (GFZ Helmholtz Centre for Geosciences, Potsdam, Germany); Jean P. Ometto (National Institute for Space Research – INPE, São José dos Campos, Brazil); Ane Alencar (Instituto de Pesquisa Ambiental da Amazônia – IPAM, Brasília, Federal District, Brazil); Celso H. L. Silva Jr (Instituto de Pesquisa Ambiental da Amazônia – IPAM, Brasília, Federal District, Brazil); Josep G. Canadell (CSIRO Oceans and Atmosphere, Canberra, ACT, Australia); Sarah E. Hancock (School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA); Jefferson G Souza (Faculty of Environment, Science and Economy, University of Exeter, Exeter, UK); Manuel Gloor (School of Geography, University of Leeds, Leeds, UK); Celso von Randow (National Institute for Space Research – INPE, São José dos Campos, Brazil); Luciana Gatti (National Institute for Space Research – INPE, São José dos Campos, Brazil); Polyanna da C. Bispo (Department of Geography, School of Environment, Education and Development, University of Manchester, Manchester, UK); Carlos Gómez-Ortiz (Department of Physical Geography and Ecosystem Science, Lund University, Lund, Sweden); Rodrigo Jimenez-Pizarro (National University of Colombia); María del Carmen Cazorla Andrade (Universidad San Francisco de Quito, Ecuador); Sebastian Diez (Centro de Investigación en Tecnologías para la Sociedad, Universidad del Desarrollo, Santiago, Chile); Stijn Hantson (Facultad de Ciencias Naturales, Universidad del Rosario, Bogotá, Colombia); Youmi Oh (Global Monitoring Laboratory, US National Oceanic and Atmospheric Administration, Boulder, Colorado, USA); Lori Bruhwiler (Global Monitoring Laboratory, US National Oceanic and Atmospheric Administration, Boulder, Colorado, USA)
How to cite: Rosan, Dr. T. and the RECCAP2 South America team: Decadal Carbon Budget and Recent Trends in South America: Insights from RECCAP2, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-7668, https://doi.org/10.5194/egusphere-egu26-7668, 2026.
