Synthesis of the land carbon fluxes of the Amazon region between 2010 and 2020

Author(s):Show less -

Rosan, Thais M. ; Sitch, Stephen ; O'Sullivan, Michael ; Basso, Luana S. ; Wilson, Chris ; Silva, Camila ; Gloor, Emanuel ; Fawcett, Dominic ; Heinrich, Viola ; Souza, Jefferson G. ; Bezerra, Francisco Gilney Silva ; von Randow, Celso ; Mercado, Lina M. ; Gatti, Luciana ; Wiltshire, Andy ; Friedlingstein, Pierre ; Pongratz, Julia ; Schwingshackl, Clemens ; Williams, Mathew ; Smallman, Luke ; Knauer, Juergen ; Arora, Vivek ; Kennedy, Daniel ; Tian, Hanqin ; Yuan, Wenping ; Jain, Atul K. ; Falk, Stefanie ; Poulter, Benjamin ; Arneth, Almut ; Sun, Qing ; Zaehle, Soenke ; Walker, Anthony P. ; Kato, Etsushi ; Yue, Xu ; Bastos, Ana ; Ciais, Philippe ; Wigneron, Jean-Pierre ; Albergel, Clement ; Aragao, Luiz E. O. C.

• Document type: Journal article
• Source: COMMUNICATIONS EARTH & ENVIRONMENT; v. 5, n. 1, p. 15-pg., 2024-01-22.

Abstract

The Amazon is the largest continuous tropical forest in the world and plays a key role in the global carbon cycle. Human-induced disturbances and climate change have impacted the Amazon carbon balance. Here we conduct a comprehensive synthesis of existing state-of-the-art estimates of the contemporary land carbon fluxes in the Amazon using a set of bottom-up methods (i.e., dynamic vegetation models and bookkeeping models) and a top-down inversion (atmospheric inversion model) over the Brazilian Amazon and the whole Biogeographical Amazon domain. Over the whole biogeographical Amazon region bottom-up methodologies suggest a small average carbon sink over 2010-2020, in contrast to a small carbon source simulated by top-down inversion (2010-2018). However, these estimates are not significantly different from one another when accounting for their large individual uncertainties, highlighting remaining knowledge gaps, and the urgent need to reduce such uncertainties. Nevertheless, both methodologies agreed that the Brazilian Amazon has been a net carbon source during recent climate extremes and that the south-eastern Amazon was a net land carbon source over the whole study period (2010-2020). Overall, our results point to increasing human-induced disturbances (deforestation and forest degradation by wildfires) and reduction in the old-growth forest sink during drought. The Brazilian Amazon was a net carbon source during recent climate extremes and the south-eastern Amazon was a net land carbon source between 2010 and 2020 due to increasing human-induced disturbance and drought, suggest bottom-up and top-down estimates of land carbon fluxes. (AU)

• FAPESP's process: 16/02018-2 - Interannual variation of Amazon Basin greenhouse gas balances and their controls in a warming and increasingly variable climate – Carbam: the Amazon carbon balance long-term study
• Grantee: Luciana Vanni Gatti
• Support Opportunities: Research Program on Global Climate Change - Thematic Grants
• FAPESP's process: 18/14006-4 - Estimation of Amazon Greenhouse Gas balances from atmospheric concentrations using inverse modelling of atmospheric transport
• Grantee: Luana Santamaria Basso
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 20/02656-4 - Net carbon exchanges in the Amazon conciliating satellite data, ground data, and atmospheric profile in a decade of observation using bottom-up approach
• Grantee: Henrique Luis Godinho Cassol
• Support Opportunities: Scholarships abroad - Research Internship - Post-doctor