Many treelines will continue to shift to higher elevations with increasing temperatures , although very few are changing as fast as the climate  and some are not moving or even shifting to lower elevations . If treelines fail to shift uphill, this will pose a risk for species of the upper-montane forest that experience range contraction at their lower range limit but lack a suitable habitat to expand into beyond their upper range limit . Changes in phenology can also pose risks to species and ecosystems , including a potential desynchronisation of mutualistic relationships like pollination and increased freezing damage due to premature emergence from winter dormancy. In European broadleaf trees, for example, the upper elevational limits of different species involve a trade-off between maximising growing season length and
IPCC
Climate Change 2022: Impacts, Adaptation and Vulnerability
IPCC Report