would previously have died and reproduce more often . Under warmer conditions, some insects that were previously innocuous have become important agents of tree mortality . Field observations show mixed effects of bark beetle-induced tree mortality on subsequent fire-caused tree mortality . From 1997 to 2018, ~5% of the forest area in the western USA died from bark beetle infestations . Under most circumstances, trees that have been weakened by drought are more vulnerable to being killed by bark beetles . In summary, climate change has contributed to bark beetle infestations that have caused much of the tree mortality in North America  .
IPCC
Climate Change 2022: Impacts, Adaptation and Vulnerability
IPCC Report