Editing IPCC:AR6/SR15/Chapter-3 (section)

==== 3.5.5.7 Boreal forests ====

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Boreal forests are ''likely'' to experience stronger local warming than the global average (WGII AR5; Collins et al., 2013) <sup>[[#fn:r1252|1252]]</sup> . Increased disturbance from fire, pests and heat-related mortality may affect, in particular, the southern boundary of boreal forests ( ''medium confidence'' ) (Gauthier et al., 2015) <sup>[[#fn:r1253|1253]]</sup> , with these impacts accruing with greater warming and thus impacts at 2°C would be expected to be greater than those at 1.5°C ( ''medium confidence'' ). A tipping point for significant dieback of the boreal forests is thought to exist, where increased tree mortality would result in the creation of large regions of open woodlands and grasslands, which would favour further regional warming and increased fire frequencies, thus inducing a powerful positive feedback mechanism (Lenton et al., 2008; Lenton, 2012) <sup>[[#fn:r1254|1254]]</sup> . This tipping point has been estimated to exist between 3°C and 4°C of global warming ( ''low confidence'' ) (Lucht et al., 2006; Kriegler et al., 2009) <sup>[[#fn:r1255|1255]]</sup> , but given the complexities of the various forcing mechanisms and feedback processes involved, this is thought to be an uncertain estimate.

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