Forest dieback is a condition in trees or woody plants in which peripheral parts are killed, either by pathogens, parasites or conditions like acid rain, drought, and more. These episodes can have disastrous consequences such as reduced resiliency of the ecosystem, disappearing important symbiotic relationships and thresholds. Some tipping points for major climate change forecast in the next century are directly related to forest diebacks.
Jizera Mountains in Central Europe in 2006
Tree dieback because of persistent drought in the Saxonian Vogtland in 2020
Tipping points in the climate system
In climate science, a tipping point is a critical threshold that, when crossed, leads to large, accelerating and often irreversible changes in the climate system. If tipping points are crossed, they are likely to have severe impacts on human society and may accelerate global warming. Tipping behavior is found across the climate system, for example in ice sheets, mountain glaciers, circulation patterns in the ocean, in ecosystems, and the atmosphere. Examples of tipping points include thawing permafrost, which will release methane, a powerful greenhouse gas, or melting ice sheets and glaciers reducing Earth's albedo, which would warm the planet faster. Thawing permafrost is a threat multiplier because it holds roughly twice as much carbon as the amount currently circulating in the atmosphere.
There many places around the globe which can pass a tipping point at a certain level of global warming. The result would be a transition to a different state.
Ground collapse caused by abrupt permafrost thaw in Herschel Island, Canada, 2013
The Northern part of the Atlantic Meridional Overturning Circulation
Modelled 21st century warming under the "intermediate" climate change scenario (top). The potential collapse of the subpolar gyre in this scenario (middle). The collapse of the entire AMOC (bottom).