iFZ Masters 2021 - Marie Schneider

Assessment of climate change as an existential risk

Anthropogenic climate change poses unimagined challenges for mankind. There are considerations that it could become significantly more extreme or even existentially threatening. However, the scientific focus so far does not seem to have been directed towards extreme temperature increases that could occur as a result of global warming.
In order to verify this, an extensive literature analysis is carried out in the first part of the thesis: it is checked how many published articles are available. For this purpose, in addition to selected temperature rises (1.0 - 10.0° C, in 0.5° C steps), nine subject areas designated as categories that are related to climate change, such as "climate extremes" or that are affected by it, such as "biodiversity" are included in the search. Overall, with increasing temperature rises, both a decreasing total number of literature and less thematically applicable results were found. From a temperature increase of 5.0°C onward, a particularly noticeable downward trend in the number of articles became noticeable. The results thus indicate possible deficits in research on extreme temperature ranges. However, the methodology and scope are not sufficient to identify verifiable research gaps for specific categories.
In the second part of the thesis, a literature review provides an insight into the existential risk posed by climate change. Anthropogenic greenhouse gas emissions do not appear to be the sole factor causing temperature increases that threaten human survival on earth. However, they have the potential to drive the climate system to a threshold at which feedback processes or even cascade effects could be triggered that would further accelerate climate change. According to the current state of knowledge, neither the feedback processes considered here nor the climate risks examined indicate a direct existential threat in this century. Some fundamental uncertainties, research speaks of still unknown quantities and knowledge gaps, however, prevent the exclusion of an existential threat posed by climate change.

Florian U Jehn et al 2021 Betting on the best case: higher end warming is underrepresented in research. Environ. Res. Lett. 16 084036

For more information:
Dr. Florian Jehn, Prof. Dr. Lutz Breuer, Landscape, Water and Biogeochemical Cycles