What does recent evidence reveal about the conflict between policymakers favoring gradual change and advocates urging urgent action to prevent climate collapse? In practical terms, the world has reached 1.5°C of warming, and the pace of warming is increasing. According to the latest report of Project Breakthrough: Collision Course, an accelerated rate of warming is likely to continue until mid-century, given the failure so far to reduce planet-warming greenhouse gas emissions.
Many impacts are occurring faster than forecast and beyond model projections, including the form, severity, and frequency of extreme events such as unprecedented heatwaves and floods.
This is happening
— There is now clear evidence that a number of crucial large-system tipping-point thresholds have been breached or are close to doing so, including polar ice sheets and land-based carbon stores including forests and permafrost, which may further increase the rate of warming. Sustainable planetary boundaries have already been exceeded.
— The physical risks may be abrupt and difficult to predict, and they may also cascade in a domino fashion, which is difficult to incorporate into climate models. So methods of understanding climate risks should pay particular attention to the plausible high-end possibilities because these worst-case scenarios will result in the greatest damage.
— Human emissions of greenhouse gases, including carbon dioxide and methane, have not yet peaked; hence, in absolute terms, decarbonization has not occurred. Contrary to global policymakers’ stated collective intent, petrostates and big oil have signaled their intention to continue to expand production in the coming decades, which would ensure that warming will go far beyond the 2°C threshold.
— The continuing growth in fossil fuel production and emissions increases the likelihood of warming exceeding 3°C, and perhaps substantially because current climate models do not adequately account for the full range of reinforcing feedbacks.
— In a 3°C hotter world, new extremes will occur of rainfall and unlivable heat, flooding and drought beyond past human experience. A committed sea-level rise of tens of meters will inundate coastal cities and deltas. Large parts of the tropics will suffer “near-unlivable” extreme heat conditions and the dry subtropics will dry out and may desertify.
— Together, these events will have catastrophic impacts on food and water security, societal stability, and global governance. There is no evidence that, at this level of warming, current human societies can be supported, and there is a significant risk that states and global economic and political networks will crash.
Reducing emissions, even very fast, is not enough to stop the systemic changes underway. Drawing atmospheric carbon dioxide levels back to safe, near-pre-industrial levels is a necessary but slow process. In the meantime, actively cooling the planet must be on the agenda if it can be done safely.
— Global climate policymaking is embedded in a culture of sustained failure, with an emphasis on incremental, market-driven processes that are structurally incapable of assessing unquantifiable risks or mitigating them. There is no longer any realistic chance of an orderly transition and large-scale economic disruption, which markets handle poorly, is now inevitable.
— As with other global and existential risks such as war and pandemics, transformative political leadership is now the key element in preventing societal collapse, but this runs contrary to the prevailing neo-liberal ideology that markets and the financial system are most efficient with little government regulation.
— The urgent need is to strengthen and rebuild state institutions in order to redirect production to climate-relevant, socially-necessary goals: to plan and manage the transition and adjustment and to provide a path out of the climate and ecological crises via an emergency mobilization that consciously makes returning to a safe climate the first priority of economics and politics.
In simple words, this is what it means
In the 2023 State of the Climate Report: Entering uncharted territory, 12 researchers warned of the “potential collapse of natural and socioeconomic systems in such a world [of 2.6°C warming] where we will face unbearable heat, frequent extreme weather events, food and fresh water shortages, rising seas, more emerging diseases, and increased social unrest and geopolitical conflict”. A year later, in 2024 State of the Climate, 14 researchers — including William Ripple, Johan Rockström, Michael E Mann, Naomi Oreskes, Tim Lenton and Stefan Rahmstorf — warned that: We are on the brink of an irreversible climate disaster. This is a global emergency beyond any doubt.
Much of the very fabric of life on Earth is imperiled. We are stepping into a critical and unpredictable new phase of the climate crisis… We are witnessing the grim reality of the forecasts as climate impacts escalate, bringing forth scenes of unprecedented disasters around the world and human and nonhuman suffering. We find ourselves amid an abrupt climate upheaval, a dire situation never before encountered in the annals of human existence. We have now brought the planet into climatic conditions never witnessed by us or our prehistoric relatives within our genus, Homo.
Whatever the words, the understanding is widely shared that contemporary nations and societies, and likely the global social system, are heading towards collapse. “If we carry on the way we are going now, I can’t see this civilization lasting to the end of this century,” says Professor Tim Lenton.
Opening the Innovation Zero Congress in London in May 2023, Prof. Johan Rockström described the path we are on: “2.5°C global mean surface temperature rise is a disaster. It’s something that humanity has absolutely no evidence that we can cope with… [There] would be a 10-metre sea-level rise. There would be a collapse of all the big biomes on planet Earth – the rainforest, many of the temperate forests – abrupt thawing of permafrost, we will have the complete collapse of marine biology…
Over one-third of the planet around the equatorial regions will be uninhabitable because you will pass the threshold of health, which is around 30°C. It’s only in some parts of the Sahara Desert today that has that kind of average temperature.”
Chatham House’s Climate Risk Assessment 2021 concluded that global food demand will be 50% higher by 2050, but crop yields may drop by 30%. As desertification spreads across the dry subtropics and one-third of the planet experiences unprecedented heat, it is not difficult to see why the assessment concluded that cascading climate impacts will “drive political instability and greater national insecurity, and fuel regional and international conflict.”
The Age of Consequences “Severe” 3°C scenario developed by a group of senior US national-security figures in 2007 describes a 3°C scenario: — Massive nonlinear events in the global environment give rise to massive nonlinear societal events. In this scenario, nations around the world will be overwhelmed by the scale of change and pernicious challenges, such as pandemic disease.
Nations’ internal cohesion will be under great stress, including in the United States, due to a dramatic rise in migration and changes in agricultural patterns and water availability. The flooding of coastal communities around the world, especially in the Netherlands, the United States, South Asia, and China, has the potential to challenge regional and even national identities. Armed conflict between nations over resources, such as the Nile and its tributaries, is likely, and nuclear war is possible.
The social consequences range from increased religious fervor to outright chaos. In this scenario, climate change provokes a permanent shift in the relationship of humankind to nature’ (emphasis added). Finally, it must be acknowledged that scientists have warned that warming of 4°C is incompatible with an organized global community, is devastating to the majority of ecosystems, and has a high probability of not being stable. The World Bank says it may be “beyond adaptation”.
