Imma Perfetto
Cosmos science journalist
Earth is barrelling towards tipping points from which there is no return for the environment or its people. Scientists concerned we were not moving fast enough to avoid damage from greenhouse gases, urgently tried to establish these baselines in 2023.
Here are 3 pieces of research released in 2023 that warn us of oncoming catastrophes, and the fundamental changes we must make to avoid them.
Collapse of the Atlantic meridional overturning circulation
Danish researchers have calculated that an essential ocean circulation process could grind to a halt this century, pushing the Earth closer to an irreversible climate change tipping point.
Their analysis of statistical early warning signals estimates how the Atlantic Meridional Overturning Circulation – or AMOC – is slowing down, and was published in the journal Nature Communications in July.
AMOC is one of the planet’s major ocean mixing processes. It is often described as a conveyer belt that circulates cold and warm salt water between the North Atlantic and the South Atlantic oceans.
The research forecasts this circulation will collapse sometime in the next 65 years under the current scenario of future emissions, which would have severe impacts on the climate in the North Atlantic region.
Reducing the concentration of greenhouse gases like carbon dioxide and methane is essential to avert runaway changes in AMOC.
On track to cross 6 risk tipping points
The Interconnected Disaster Risks Report 2023 report, released in October, warns that the Earth is on course to cross 6 ‘risk’ tipping points:
- Accelerating extinctions: an ecosystem loses key species that trigger cascading extinctions of dependent species, leading to the ecosystem collapse.
- Groundwater depletion: depleted groundwater resources fall below a level that we can access, putting food production systems at risk of failure.
- Mountain glaciers melting: glaciers melt faster than the ice can be replaced, and fresh meltwater availability steadily declines.
- Space debris: Earth’s orbit becomes so crowded with human-made debris that a collision sets off a chain reaction, threatening our ability to operate satellites.
- Unbearable heat: beyond a “wet-bulb temperature” of 35°C, humans cannot survive for more than six hours.
- Uninsurable future: when insurance becomes unavailable or unaffordable, due to climate change increasing the damage caused by weather-related disasters.
The report identifies the urgent need to shift towards making transformative change in order to avoid them.
The Global Tipping Points Report
Another piece of research – The Global Tipping Points Report – also sounded the alarm on climate when it was launched at COP28 in December.
The report warns that if current trends continue, at least 5 tipping points are already at risk of being crossed due to warming, right now. These are the Greenland and West Antarctic Ice Sheets, warm-water coral reefs, North Atlantic subpolar gyre circulation, and permafrost regions.
If the world exceeds 1.5°C global warming, 3 further critical systems are threatened with collapse in the 2030s: boreal forest, mangroves, and seagrass meadows.
It warns that crossing one harmful tipping point could trigger others, causing a domino effect of accelerating unmanageable change.
But the authors also provide 6 key recommendations to alter our course, including: eliminating fossil fuel emissions by 2050, introducing positive changes in high-emitting sectors like transportation, and convening a global summit on tipping points.
