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In addition to these observations, there has also been work on projecting future forest trends. A 2018 study of the seven tree species dominant in the Eastern Canadian forests found that while 2°C warming alone increases their growth by around 13% on average, water availability is much more important than temperature and further warming of up to 4°C would result in substantial declines unless matched by increases in precipitation.<ref>{{Cite journal |last1=D’Orangeville |first1=Loïc |last2=Houle |first2=Daniel |last3=Duchesne |first3=Louis |last4=Phillips |first4=Richard P. |last5=Bergeron |first5=Yves |last6=Kneeshaw |first6=Daniel |date=10 August 2018 |title=Beneficial effects of climate warming on boreal tree growth may be transitory |journal=Nature Communications |language=en |volume=9 |issue=1 |page=3213 |doi=10.1038/s41467-018-05705-4 |pmid=30097584 |pmc=6086880 }}</ref> A 2019 study suggested that the forest plots commonly used to evaluate boreal forest response to climate change tend to have less evolutionary competition between trees than the typical forest, and that with strong competition, there was little net growth in response to warming.<ref>{{Cite journal |last1=Luo |first1=Yong |last2=McIntire |first2=Eliot J. B. |last3=Boisvenue |first3=Céline |last4=Nikiema |first4=Paul P. |last5=Chen |first5=Han Y. H. |date=17 June 2019 |title=Climatic change only stimulated growth for trees under weak competition in central boreal forests |url=https://besjournals.onlinelibrary.wiley.com/doi/10.1111/1365-2745.13228 |journal=Journal of Ecology |language=en |volume=9 |pages=36–46 |doi=10.1111/1365-2745.13228 |s2cid=196649104 }}</ref> Climatic change only stimulated growth for trees under weak competition in central boreal forests. A 2021 paper had confirmed that the boreal forests are much more strongly affected by climate change than the other forest types in Canada and projected that most of the eastern Canadian boreal forests would reach a tipping point around 2080 under the [[Representative Concentration Pathway|RCP]] 8.5 scenario which represents the largest potential increase in anthropogenic emissions.<ref>{{Cite journal |last1=Boulanger |first1=Yan |last2=Puigdevall |first2=Jesus Pascual |date=3 April 2021 |title=Boreal forests will be more severely affected by projected anthropogenic climate forcing than mixedwood and northern hardwood forests in eastern Canada |url=https://link.springer.com/article/10.1007/s10980-021-01241-7 |journal=Landscape Ecology |language=en |volume=36 |issue=6 |pages=1725–1740 |doi=10.1007/s10980-021-01241-7 |s2cid=226959320 }}</ref> Another 2021 study projected that under the "moderate" [[Shared Socioeconomic Pathways|SSP2-4.5]] scenario, boreal forests would experience a 15% worldwide increase in biomass by the end of the century, but this would be more than offset by the 41% biomass decline in the tropics.<ref>{{Cite journal |last1=Larjavaara |first1=Markku |last2=Lu |first2=Xiancheng |last3=Chen |first3=Xia |last4=Vastaranta |first4=Mikko |date=12 October 2021 |title=Impact of rising temperatures on the biomass of humid old-growth forests of the world |journal=Carbon Balance and Management |language=en |volume=16 |issue=1 |page=31 |doi=10.1186/s13021-021-00194-3 |pmid=34642849 |pmc=8513374 }}</ref> In 2022, the results of a 5-year warming experiment in North America had shown that the juveniles of tree species which currently dominate the southern margins of the boreal forests fare the worst in response to even 1.5°C or +3.1 °C of warming and the associated reductions in precipitation. While the temperate species which would benefit from such conditions are also present in the southern boreal forests, they are both rare and have slower growth rates.<ref>{{Cite journal |last1=Reich |first1=Peter B. |last2=Bermudez |first2=Raimundo |last3=Montgomery |first3=Rebecca A. |last4=Rich |first4=Roy L. |last5=Rice |first5=Karen E. |last6=Hobbie |first6=Sarah E. |last7=Stefanski |first7=Artur |date=10 August 2022 |title=Even modest climate change may lead to major transitions in boreal forests |url=https://www.nature.com/articles/s41586-022-05076-3 |journal=Nature |language=en |volume=608 |issue=7923 |pages=540–545 |doi=10.1038/s41586-022-05076-3 |pmid=35948640 |s2cid=251494296 }}</ref>
A 2022 assessment of [[tipping points in the climate system]] designated two inter-related tipping points associated with climate change - the die-off of taiga at its southern edge and the area's consequent reversion to [[grassland]] (similar to the [[Amazon rainforest]] dieback) and the opposite process to the north, where the rapid warming of the adjacent [[tundra]] areas converts them to taiga. While both of these processes can already be observed today, the assessment believes that they would likely not become unstoppable (and thus meet the definition of a tipping point) until global warming of around 4 °C. However, the certainty level is still limited and it is possible that 1.5 °C would be sufficient for either tipping point; on the other hand, the southern die-off may not be inevitable until 5 °C, while the replacement of tundra with taiga may require 7.2°C. Once the "right" level of warming is met, either process would take at least
==Other threats==
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