Vulnerability of human well-being to adverse ecological, social, and other forms of surprise varies among the scenarios, but it is greatest in order from strength, with a focus on security through boundaries and where the society is not proactive to the environment.
Scenarios that limit deforestation show relatively better preservation of regulating services. Tropical deforestation could be reduced by a combination of reduced tropical hardwood consumption in north, technological developments leading to substitution, and slower population growth in South (Techno Garden) or through greater protection of local ecosystems (Adapting Mosaic).
In contrast, in scenarios, those are not proactive on environment, a combination of market forces, undervaluation, and feedbacks lead to substantial deforestation not only in tropics but also in large swaths of Siberia (order from Strength and Global Orchestration).
Deforestation increasingly interacts with climate change in all scenarios, causing not only more flooding during storms but also more fires during droughts, greatly increasing the risk of runaway climate change.
Terrestrial ecosystems currently absorb C02 at a rate of about 1-2 rigatonis of carbon per year (with medium certainty) and thereby contribute to the regulation of climate, but the future of this service is uncertain.
Deforestation is expected to reduce carbon sink most strongly in a globalized world with a focus on security through boundaries (Order from Strength) (medium certainty). Carbon release or uptake by ecosystems affects C02 and CH4 content of atmosphere at global scale and thereby global climate.
Currently, biosphere is a net sink of carbon, absorbing approximately 20% of fossil fuel emissions. It is likely that future of this service will be greatly affected by expected land use change.
In addition, a higher atmospheric C02 concentration is expected to enhance net productivity, but this does not necessarily lead to an increase in carbon sink. Limited understanding of soil respiration processes, and their response to changed agricultural practices, generates uncertainty about future of this sink.