Harmful tipping points in the natural world pose some of the gravest threats faced by humanity. Their triggering will severely damage our planet’s life-support systems and threaten the stability of our societies.
In the Summary Report:
• Narrative summary
• Global tipping points infographic
• Key messages
• Key Recommendations
Executive summary
• Section 1
• Section 2
• Section 3
• Section 4
This report is for all those concerned with tackling escalating Earth system change and mobilising transformative social change to alter that trajectory, achieve sustainability and promote social justice.
In this section:
• Foreword
• Introduction
• Key Concepts
• Approach
• References
Considers Earth system tipping points. These are reviewed and assessed across the three major domains of the cryosphere, biosphere and circulation of the oceans and atmosphere. We then consider the interactions and potential cascades of Earth system tipping points, followed by an assessment of early warning signals for Earth system tipping points.
Considers tipping point impacts. First we look at the human impacts of Earth system tipping points, then the potential couplings to negative tipping points in human systems. Next we assess the potential for cascading and compounding systemic risk, before considering the potential for early warning of impact tipping points.
Considers how to govern Earth system tipping points and their associated risks. We look at governance of mitigation, prevention and stabilisation then we focus on governance of impacts, including adaptation, vulnerability and loss and damage. Finally, we assess the need for knowledge generation at the science-policy interface.
Focuses on positive tipping points in technology, the economy and society. It provides a framework for understanding and acting on positive tipping points. We highlight illustrative case studies across energy, food and transport and mobility systems, with a focus on demand-side solutions (which have previously received limited attention).
Remote sensing datasets also have potential applications in the detection of tipping points in managed vegetation systems like pastoral systems (Swingedouw et al., 2020). For instance, (Fernandez-Gimenez et al., 2017) have used Earth observation data to monitor the impact of increased livestock pressure on grazing lands as well as potential shifts in crop density and vegetation types (Figure 2.5.5).
With normalised difference vegetation index (NDVI) data derived from the Advanced Very-High-Resolution Radiometer (AVHRR) and Moderate Resolution Imaging Spectroradiometer (MODIS) missions, the authors detected higher autocorrelation and variance in variability of forage production, which could be interpreted as a potential tipping point in rangeland conditions. Implications for pastoral communities can be significant as grazing lands transition to a more degraded ecosystem that cannot sustain their livelihood.
In tropical forest settings, too, remote sensing products have been used to identify potential critical transitions. (Verbesselt et al., 2016) used MODIS NDVI and RADAR Vegetation Optical Depth (VOD) monthly data time series of evergreen tropical forests across Africa, South East Asia and South America to detect declining rates of recovery through temporal autocorrelation. The results provide practical thresholds to anticipate collapse of tropical forests facing drought and high temperatures. (See also Chapter 1.6 for further analysis outlining how proximity of landscapes to human activity leads to lower resilience.)