Editing IPCC:AR6/SRCCL/Chapter-2 (section)

==== 2.3.1.3 Gross emissions and removals contributing to AFOLU emissions ====

<div id="section-2-3-1-3-gross-emissions-and-removals-contributing-to-afolu-emissions-block-1"></div>

The modelled AFOLU flux of 5.5 ± 3.7 GtCO <sub>2</sub> yr <sup>–1</sup> over the period 2008–2017 represents a net value. It consists of both gross emissions of CO <sub>2</sub> from deforestation, forest degradation and the oxidation of wood products, as well as gross removals of CO <sub>2</sub> in forests and soils recovering from harvests and agricultural abandonment (Figure 2.4). The uncertainty of these gross fluxes is high because few studies report gross fluxes from AFOLU. Houghton and Nassikas (2017 <sup>[[#fn:r583|583]]</sup> ) estimated gross emissions to be as high as 20.2 GtCO <sub>2</sub> yr <sup>–1</sup> ( ''limited evidence, low agreement'' ) (Figure 2.4), and even this may be an underestimate because the land-use change data used from FAOSTAT (Tubiello et al. 2013 <sup>[[#fn:r584|584]]</sup> ) is itself a net of all changes within a country.

Gross emissions and removals of CO <sub>2</sub> result from rotational uses of land, such as wood harvest and shifting cultivation, including regrowth. These gross fluxes are more informative for assessing the timing and potential for mitigation than estimates of net fluxes, because the gross fluxes include a more complete accounting of individual activities. Gross emissions from rotational land use in the tropics are approximately 37% of total CO <sub>2</sub> emissions, rather than 14%, as suggested by net AFOLU emissions (Houghton and Nassikas 2018 <sup>[[#fn:r585|585]]</sup> ). Further, if the forest is replanted or allowed to regrow, gross removals of nearly the same magnitude would be expected to continue for decades.

<div id="section-2-3-1-4-gross-emissions-and-removals-contributing-to-the-non-anthropogenic-land-sink"></div>

<span id="gross-emissions-and-removals-contributing-to-the-non-anthropogenic-land-sink"></span>