Posted on July 19, 2022

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Agriculture, forestry and other land use (AFOLU) is a significant net source of GHG emissions (high confidence), contributing to about 23% of anthropogenic emissions of carbon dioxide (CO₂), methane (CH_cuatro) and nitrous oxide (N₂O) combined as CO₂ equivalents in 2007–2016 (medium confidence). ₂, CH₄ and N₂O to and from the atmosphere (high confidence). These fluxes are affected simultaneously by natural and human drivers, making it difficult to separate natural from anthropogenic fluxes (very high confidence).

The total net land-atmosphere flux of CO₂ on both managed and unmanaged lands very likely provided a global net removal from 2007 to 2016 according to models (-6.0 ± 3.7 CO₂ yr –1 , likely range). 2 ± 2.6 GtCO₂ yr –1 (likely range) driven by land cover change, including deforestation and afforestation/reforestation, and wood harvesting (accounting for about 13% of total net anthropogenic emissions of CO₂) (medium confidence), and (ii) modelled net removals due to non-anthropogenic processes are 11.2 ± 2.6 GtCO₂ yr –1 (likely range) on managed and unmanaged lands, driven by environmental changes such as increasing CO₂, nitrogen deposition and changes in climate (accounting for a removal of 29% of the CO₂ emitted from all anthropogenic activities (fossil fuel, industry and AFOLU) (medium confidence).

Global models and national GHG inventories use www.datingmentor.org/nl/dine-app-overzicht different methods to estimate anthropogenic CO₂ emissions and removals for the land sector. Consideration of differences in methods can enhance understanding of land sector net emission such as under the Paris Agreement’s global stocktake (medium confidence). g., deforestation, afforestation), and differ for managed forest. Global models consider as managed forest those lands that were subject to harvest whereas, consistent with IPCC guidelines, national GHG inventories define managed forest more broadly. On this larger area, inventories can also consider the natural response of land to human-induced environmental changes as anthropogenic, while the global model approach

treats this response as part of the non-anthropogenic sink. For illustration, from 2005 to 2014, the sum of the national GHG inventories net emission estimates is 0.1 ± 1.0 GtCO₂yr –1 , while the mean of two global bookkeeping models is 5.1 ± 2.6 GtCO₂yr –1 (likely range).

Which net removing comes with a few significant section: (i) modelled online anthropogenic pollutants off AFOLU try 5

The gross emissions from AFOLU (one-third of total global emissions) are more indicative of mitigation potential of reduced deforestation than the global net emissions (13% of total global emissions), which include compensating deforestation and afforestation fluxes (high confidence). The net flux of CO₂ from AFOLU is composed of two opposing gross fluxes: (i) gross emissions (20 GtCO₂ yr –1 ) from deforestation, cultivation of soils and oxidation of wood products, and (ii) gross removals (–14 GtCO₂ yr –1 ), largely from forest growth following wood harvest and agricultural abandonment (medium confidence).

Land is a net source of CH₄, accounting for 44% of anthropogenic CH₄ emissions for the 2006–2017 period (medium confidence). The pause in the rise of atmospheric CH₄ concentrations between 2000 and 2006 and the subsequent renewed increase appear to be partially associated with land use and land use change. The recent depletion trend of the 13C isotope in the atmosphere indicates that higher biogenic sources explain part of the current CH₄ increase and that biogenic sources make up a larger proportion of the source mix than they did before 2000 (high confidence). In agreement with the findings of AR5, tropical wetlands and peatlands continue to be important drivers of inter- annual variability and current CH₄ concentration increases (medium evidence, high agreement). Ruminants and the expansion of rice cultivation are also important contributors to the current trend (medium evidence, high agreement). There is significant and ongoing accumulation of CH₄ in the atmosphere (very high confidence).

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