Earth on verge of climate disaster

Humanity is facing imminent and severe threats as the Earth warms due to increasing carbon pollution, caution scientists. The Global Tipping Points report identifies five critical natural tipping points at risk of being breached, with three more potential in the 2030s if global temperatures rise 1.5C (2.7F) above pre-industrial levels.

While these planetary shifts won’t necessarily lead to uncontrolled temperature spikes over the centuries, they could result in irreversible and extensive harm to both people and the environment. These tipping points could set off cascading effects, including the loss of entire ecosystems, disruptions to staple crop growth, mass displacement, political instability, and financial collapse.

Among the tipping points at risk are the collapse of large ice sheets in Greenland and the West Antarctic, widespread melting of permafrost, coral reef death in warm waters, and the disruption of a North Atlantic oceanic current. Unlike gradual shifts seen in some climate phenomena, these systems can abruptly transition from one state to another, permanently altering the planet’s functioning, sometimes with sudden shocks.

While uncertainties surround the timing of these system shifts, the report identifies three potential additions to the list of at-risk tipping points. These include the potential die-off of mangroves and seagrass meadows in certain regions with a temperature rise between 1.5C and 2C, as well as the tipping of boreal forests, which could occur as early as 1.4C of heating or as late as 5C.

Researchers say the current emissions targets for 2030 are on track to cause a 2.5C temperature rise by the end of the century, surpassing the 1.5C limit promised by countries in previous summits. Certain shifts have the potential to create feedback loops, contributing to further planetary warming or altering weather patterns in ways that trigger additional tipping points. The interconnectedness of these systems raises the possibility of “tipping cascades,” where the impact of one event sets off a chain reaction. For example, the disintegration of the Greenland ice sheet could prompt an abrupt shift in the Atlantic Meridional Overturning Circulation, a crucial current delivering heat to the Gulf Stream, which, in turn, may intensify the El Niño pattern.

These threats should be taken very seriously, as crossing such thresholds could lead to fundamental and abrupt changes with irreversible implications for essential parts of the Earth system over the next hundreds or thousands of years.

The Intergovernmental Panel on Climate Change acknowledged the unclear nature of tipping points but underscored the increasing likelihood of dangers as the planet continues to heat up. It notes that risks associated with large-scale singular events or tipping points transition from high risk between 1.5C to 2.5C and to very high risk between 2.5C to 4C.

The tipping point report also explores the “positive tipping points,” such as the declining cost of renewable energy and the rise in electric vehicle sales. However, it underscores that these positive shifts don’t occur spontaneously; they require facilitation through innovation stimulation, market shaping, business regulation, and public education and mobilization.