Recurrent droughts increase risk of cascading tipping events by outpacing adaptive capacities in the Amazon rainforest
- 1Earth System Analysis and Complexity Science, Potsdam Institute for Climate Impact Research, Potsdam, Germany (nico.wunderling@pik-potsdam.de)
- 2Stockholm Resilience Centre, Stockholm University, Stockholm, Sweden
- 3High Meadows Environmental Institute, Princeton University, Princeton, USA
- 4Copernicus Institute of Sustainable Development, Utrecht University, Utrecht, The Netherlands
- 5Department of Physics, Federal University of Santa Catarina, Florianópolis, Brazil
- 6Department of Plant Biology, University of Campinas, Campinas, Brazil
- 7Physics Department, University of Maryland Baltimore County, Baltimore, USA
- 8Institute of Physics, University of São Paulo, São Paulo, Brazil
- 9Institute of Physics and Astronomy, University of Potsdam, Potsdam, Germany
Since the foundational paper by Lenton et al. (2008, PNAS), tipping elements in the climate system have attracted great attention within the scientific community and beyond. One of the most important tipping elements is the Amazon rainforest. Under ongoing global warming, it is suspected that extreme droughts such as those in 2005 and 2010 occur significantly more often, up to nine out of ten years from the mid to late 21st century onwards (e.g. Cox et al., 2008, Nature; Cook et al., 2020, Earth’s Future).
In this work, we quantify how climates ranging from normal rainfall conditions to extreme droughts may generate cascading tipping events through the coupled forest-climate system. For that purpose, we make use of methods from nonlinear dynamical systems theory and complex networks to create a conceptual model of the Amazon rainforest, which is dependent on itself through atmospheric moisture recycling.
We reveal that, even when the rainforest is adapted to past local conditions of rainfall and evaporation, parts of the rainforest may still tip when droughts intensify. We uncover that forest-induced moisture recycling exacerbates tipping events by causing tipping cascades that make up to one-third (mean+-s.d. = 35.9+-4.9%) of all tipping events. Our results imply that if the speed of climate change might exceed the adaptation capacity of the forest, knock-on effects through moisture recycling impede further adaptation to climate change.
Further, we use a network analysis method to compare the four main terrestrial moisture recycling hubs: the Amazon Basin, the Congo Rainforest, South Asia and the Indonesian Archipelago. By evaluating so-called network motifs, i.e. local-scale network structures, we quantify the fundamentally different functioning of these regions. Our results indicate that the moisture recycling streams in the Amazon Basin are more vulnerable to disturbances than in the three other main moisture recycling hubs.
How to cite: Wunderling, N., Staal, A., Wolf, F., Sakschewski, B., Hirota, M., Tuinenburg, O. A., Donges, J. F., Barbosa, H. M. J., and Winkelmann, R.: Recurrent droughts increase risk of cascading tipping events by outpacing adaptive capacities in the Amazon rainforest, EGU General Assembly 2023, Vienna, Austria, 24–28 Apr 2023, EGU23-5722, https://doi.org/10.5194/egusphere-egu23-5722, 2023.
