Chapter 6A: The Amazon Carbon Budget

Abstract

The main objective of this cross-chapter is to summarize the status of the Amazon as a source or sink of carbon (C). The processes and studies involved are detailed in other SPA chapters. The major challenge of determining the Amazon’s status as a net C source or sink at a continental scale is that many complex processes contribute to C fluxes. Unlike in other regions, emissions from the burning of fossil fuels are minor contributors to Amazonian fluxes. Instead, the major sinks and sources of C to the atmosphere are associated with the net accumulation or loss of biomass, with losses including deforestation, biomass burning, and tree mortality followed by decomposition. Biomass accumulates in areas where tree growth exceeds losses. The Amazon includes not only intact forests, also but degraded and logged forests, natural non-forests, agricultural and urban areas, and aquatic systems including wetlands that all contribute to regional carbon cycling.

Increased Amazon carbon emissions mainly from decline in law enforcement

“…This indicates that Amazonia is a carbon source to the atmosphere, including all natural and anthropogenic processes of CO2 emissions and absorptions. This result is a direct indication of the regional source in the global carbon budget, though there are well known discrepancies from many studies using different methodologies (bottom-up, topdown techniques, and a wide variety of global, regional and inversion models) [1][2][3][4]13,[20][21][22][23][24] .…”

Impactos Humanos nas Emissões de Carbono & Perdas nos Serviços Ecossistêmicos

“…As emissões de carbono apresentam variação regional, influenciadas por diferentes condições climáticas devido à magnitude do desmatamento e da degradação florestal 21 . Após uma queda de 83% de 2004 a 2012, as taxas de desmatamento na Amazônia aumentaram, especialmente no "arco do desmatamento", contribuindo para um aquecimento substancial nesta região 19 . Enquanto a aplicação de políticas de proteção ambiental no Brasil foi responsável por reduzir o desmatamento em 83% de 2004 a 2012, mais recentemente (desde 2016, e mais intensificado desde 2019), a desmontagem dessas políticas causou um aumento de 76% no desmatamento associado a eventos de incêndio, alarmando a comunidade nacional e internacional e causando protestos em todo o mundo 22 .…”

HUMAN IMPACTS ON CARBON EMISSIONS & LOSSES IN ECOSYSTEMS SERVICES: THE NEED FOR RESTORATION AND INNOVATIVE CLIMATE FINANCe FOR THE AMAZON

“…Estimates of the Amazon's carbon balance over the last decade indicate that the Amazon as a whole is now a carbon source (i.e., C losses to the atmosphere) on the order of 1.1 Gt CO 2 yr -1 (Total Carbon Flux) (Figure 1). In addition, the emission by biomass burning is responsible for 1.5 Gt CO 2 yr -1 [19][20][21] .…”

“…From 2004 to 2012, Brazilian policies and forest law enforcement approaches were important instruments related to the reduction of deforestation supporting natural forest regeneration 30,31 . In recent years (2019 and 2020, compared to 2010-2018), an increase in deforestation was observed associated with a 13% increase in cattle herds, a 70% increase in the area planted with grains (soybeans and corn), and a 700% in wood exports in the Amazon 19 . The increase in the deforestation rates since 2013 has led to the failure of the targets stipulated by the National Climate Change Policy (Law nº 12,187/2009) to reduce deforestation to 3,925 km 2 by 2020 31 .…”