The opportunity to secure a “liveable” future on Earth is rapidly disappearing, a major new report by the world’s top scientists has warned.
Half of the world’s population is now “highly vulnerable” to the impacts of the climate crisis, according to the second part of a sweeping report by the Intergovernmental Panel on Climate Change (IPCC).
In the most dire warning on climate change to date, it finds that human-caused global warming is already dangerously disrupting the natural world and some of its effects are now “irreversible”. It says that humans and nature are being pushed beyond their abilities to adapt and targeted action must be taken now if we are to have any hope of avoiding the very worst impacts of climate change.
“Climate change is a threat to human well-being and planetary health,” the authors warn. “Any further delay in concerted anticipatory global action on adaptation and mitigation will miss a brief and rapidly closing window of opportunity to secure a liveable and sustainable future for all.”
The study – published just four months on from the COP26 climate conference in Glasgow – is the most comprehensive overview of global climate change in seven years. It explores how rising temperatures are affecting societies and ecosystems, and what actions must be taken if the world is to adapt.
Our actions today will shape how people adapt and nature responds to increasing climate risks
Exceeding 1.5C of warming – the ambitious target set by the Paris Agreement in 2015 – will happen in the “near-term,” it says. At the current 1.1C of warming, the world is already witnessing more severe and more frequent heatwaves, storms, flooding, and fires. Even temporarily surpassing 1.5C would cause unavoidable increases in multiple hazards, the IPCC says.
Between 2010 and 2020, 15 times more people died from floods, droughts and storms in very vulnerable regions including parts of Africa, South Asia and Central and South America, than in other parts of the world.
Keeping as close to 1.5C as possible would dramatically reduce threats compared to higher warming levels but “cannot eliminate them all,” the report adds. It says adapting to climate change will become more difficult as temperatures continue to rise, going from challenging to “impossible” in some regions if temperatures exceed 2C.
If temperatures rise to between 1.7 and 1.8C above the 1850s level, then the report states that half the human population could be exposed to periods of life-threatening climatic conditions arising from heat and humidity.
Hoesung Lee, chair of the IPCC, called the report “a dire warning about the consequences of inaction.” He said: “Our actions today will shape how people adapt and nature responds to increasing climate risks.”
A key moment
Prof Debra Roberts, co-chair of the IPCC, added: “Our report clearly indicates that places where people live and work may cease to exist, that ecosystems and species that we’ve all grown up with and that are central to our cultures and inform our languages may disappear.
“So this is really a key moment. Our report points out very clearly, this is the decade of action, if we are going to turn things around.”
Other key findings include:
- Around 3.3 to 3.6 billion people live in conditions that are “highly vulnerable” to climate change.
- While up to 14 per cent of species assessed will likely face a very high risk of extinction if the world warms by 1.5C, this will rise to up to 29 per cent of species at 3C of warming.
- Adverse impacts are “cascading” along coasts and cities, and in mountainous regions. These hazards trigger tipping points in sensitive ecosystems, and in systems impacted by ice melt, permafrost thaw and changing hydrology in polar regions.
- Weather extremes are occurring simultaneously, exposing millions of people to acute food and water insecurity especially in Africa, Asia, Central and South America, on small islands and in the Arctic.
- Mental health impacts, assessed for the first time, are linked to rising heat, trauma from extreme events, and loss of livelihoods and culture.
The report, involving 270 climate experts from 67 countries, found that many parts of the natural world are near the “hard limits” of their natural adaptation including warm water coral reefs, tropical rainforests and small island communities.
Some communities living along coastlines and small-holder farmers are facing so-called “soft limits” to adapting to climate impacts, such as a lack of money.