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).
A collapse of the AMOC would lead to widescale cooling of the northern hemisphere, particularly in Europe and North America (Jackson et al., 2015; Stouffer et al., 2006), which could lead to increased demand for energy for heating. One study (Jacob et al., 2005) suggested increases in heating energy consumption of 10-20 per cent in the UK and Europe. Regional changes in weather patterns might also have an impact on energy generation, for instance through changes in precipitation (Haarsma, 2015; Jackson et al., 2015) which might affect hydropower, changes in average cloud amounts (Jackson et al., 2015; Laurian, 2010) which could affect solar power, and changes in windiness (Jackson et al., 2015) which could affect wind energy. However, these potential societal impacts from regional changes in weather patterns from AMOC collapse have not yet been assessed.
Thermal power stations (including both fossil fuel and nuclear) are often sited on coasts to provide access to water for cooling, so are potentially vulnerable to sea level rise triggered by ice sheet tipping points, while Amazon dieback could affect the production of electricity from hydropower on rivers in the Amazon region. A potential 40 per cent decline in forest cover by 2050 is projected to lead to hydrological power generation in the Xingu basin to fall to approximately 25 per cent of maximum installed capacity due to reduced river discharge (Stickler et al., 2013).