The Intergovernmental Panel on Climate Change (IPCC) just released the summary findings of its Sixth IPCC report (AR6). The IPCC produces a set of three reports every seven years bringing together the best available scientific evidence from specialised expert working groups from all over the world. The reports detail the state of science and make recommendations for adaptation and mitigation. This final summary report brings together the global picture.
To catch up on the key points for Australia’s adaptation efforts, see this summary and these webinars with IPCC authors and adaptation experts from across Australia.
Globally, more than 100 years of burning fossil fuels and changes to land use have led to a world that is on average 1.1°C warmer than before the beginning of industrialisation. The Bureau of Meteorology estimates Australia has warmed an average of 1.47°C since 1910.
This latest round of IPCC reporting has dire news for the planet. Continued increases in greenhouse gas emissions are increasing the challenges of addressing climate change. While more frequent and more intense extreme weather events are having increasingly dangerous impacts on natural spaces and people in every region of the world – including Australia. According to the IPCC, the pace and scale of what has been done so far, and current agreed emission reduction plans, are insufficient to tackle climate change.
Key takeaways from the summary report
Our CO2 concentrations are higher than at any other time humans have been on Earth
At 410 parts per 21 million in 2019, the IPCC is highly confident that atmospheric CO2 concentrations were higher than at any time in at least 2 million years. Concentrations of methane (1866 parts per billion) and nitrous oxide (332 parts per billion) were higher than at any time in at least 800,000 years. Emissions have only risen since 2019.
The majority of these emissions come from wealthy nations. The richest 10% of the global population are disproportionately responsible for 34–45% of emissions, while the poorest 50% contribute just 13–15%.
Want to know more about the state of emissions? Read more with the Global Carbon Project or watch Pep Canadell explain our carbon budget.
We can already observe the changes in our atmosphere, oceans, land and ecosystems
Increases in greenhouse gas emissions are “unequivocally” caused by human activities. These emissions are driving sea levels to rise more quickly than at any time in more than 100 years of measurements.
Want to explore how sea level rise could impact Australia? Explore Coastal Extremes with CANUTE
Increases in emissions are also driving observed changes in extremes such as heatwaves, heavy precipitation, droughts and tropical cyclones. Australians have become acutely aware of the impact of these changes in recent years. Human influence has also increased the chance of more than one extreme event happening at once – compound events that can be incredibly dangerous. For example, heatwaves, drought or bushfires occurring simultaneously as happened over Black Summer.
This, as well as increases in extreme heat events, have massive impacts on the health of all species. If warming continues unchecked, 80-100% of species in tropical latitudes will be exposed to dangerous temperatures that could drive extinction. Species over much of northern Australia, including regions like the Kimberly and Daintree are clearly at risk as the planet warms.
For humans, the reported risks are sobering. Increasing weather and climate extreme events have already exposed 27 million people to acute food insecurity and reduced water insecurity. Indigenous people are disproportionately affected globally.
The report shows there has been an increase in food, water and vector borne diseases, trauma from extreme weather, mental health challenges and displacement. Continued warming poses an increasing risk to human health.
If warming continues unchecked, much of northern Australia will experience dangerous heat every day of the year.
This figure just considers risks to human health from temperature and humidity changes – not prolonged heat extremes. Source: IPCC 2023.
What we do now matters: urgent changes are needed to protect future generations from dangerous warming
Hub scientists estimate that for the Paris Agreement to be met, global average temperatures must not rise by more than 1.5°C by 2030. To achieve this, emissions reduction pledges must be seven times greater than they currently are. To limit global warming to 2°C, pledges must be four times greater.
But efforts to reduce emissions don’t just avoid future dangers – they have tangible benefits now.
“Mainstreaming effective and equitable climate action will not only reduce losses and damages for nature and people, it will also provide wider benefits,” said IPCC Chair Hoesung Lee.
“This Synthesis Report underscores the urgency of taking more ambitious action and shows that, if we act now, we can still secure a liveable sustainable future for all.”
Protecting natural spaces is recommended to help adapt to our changing climate.
The report emphasises the need to protect natural spaces highlighting the connection between climate, ecosystems and society. To help ensure a healthy planet approximately 30-50% of the Earth’s land, freshwater and ocean need to be conserved. Currently, less than 15% of the land, 21% of the freshwater and 8% of ocean are protected globally.
We are already seeing the impacts of climate change and our choices now will impact us and future generations.
The impacts of climate change will affect all of us.
Source: IPCC 2023.