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September 2025 ranked as the third-warmest month globally for land and ocean surface temperatures. [1]
Greenhouse-gas accumulation continues to drive unusual heat patterns worldwide. [1]
Sea-surface temperatures remain near record highs, stressing marine ecosystems. [1]
Long-term forecasts predict that global temperatures between 2025 and 2029 will likely exceed 1.5 °C above pre-industrial levels. [2]
There is a high probability that at least one year in the next five will set new temperature records. [2]
National climate plans show the potential for declining emissions, but current commitments fall far short of limiting warming to 1.5 °C. [3]
Only a third of countries explicitly support a shift away from fossil fuels in their pledges. [4]
The Paris Agreement goals remain at risk unless stronger and faster action is taken globally. [6]
These trends underline the urgency for governments, industry, and civil society to accelerate mitigation and adaptation measures worldwide. [6]
Humanity has entered a high-stakes decade where delayed action could lock in devastating warming and irreversible climate impacts. [2]
Global Temperatures: A Stark Signal
September 2025 was the third-warmest September on record, with both land and sea surface temperatures continuing at unusually high levels, according to recent data. [1]
The Copernicus Climate Change Service reports that global surface air temperatures for September were approximately 0.66 °C above the 1991–2020 monthly average and about 1.47 °C above the 1850–1900 pre-industrial baseline. [1]
Sea-surface temperatures averaged near 20.72 °C for the month, ranking among the highest ever recorded for September and reflecting widespread marine heat stress. [1]
These persistently high temperatures across both land and ocean point to the continuing influence of greenhouse-gas accumulation in the atmosphere. [1]
Warming oceans can fuel marine heatwaves, reduce carbon absorption and amplify extreme weather risks. [1]
Outlook For The Next Five Years
The World Meteorological Organization (WMO) projects that average global temperatures between 2025 and 2029 are likely to be 1.2–1.9 °C above the 1850–1900 baseline. [2]
There is an 80 % chance that at least one year in that period will exceed the warmest year on record so far, and an 86 % chance that one year will exceed 1.5 °C above pre-industrial levels. [2]
The WMO notes a roughly 70 % chance that the five-year average warming over 2025–29 will exceed 1.5 °C. [2]
While the Paris Agreement’s 1.5 °C limit refers to multi-decadal averages, these forecasts show the narrowing window for keeping warming below that threshold. [2]
Arctic regions continue to warm much faster than the global average, increasing risks of ice melt, sea-level rise and permafrost thaw. [2]
National Climate Plans: Progress, But Insufficient
The latest UNFCCC assessment shows that if countries meet their current climate plans, global emissions may start to decline this decade—for the first time in modern history. [3]
Emissions could fall around 10 % by 2035 compared with 2019 levels, but that remains far short of the 60 % reduction needed to limit warming to 1.5 °C. [3]
Only one-third of national climate plans explicitly commit to a transition away from fossil fuels. [4]
Some countries are still expanding fossil-fuel production, locking in long-lived carbon-intensive infrastructure. [4]
Australia’s Position & Global Implications
Australia’s proposed 2035 target aims for a 62–70 % reduction in emissions from 2005 levels, but experts warn this ambition may be insufficient. [5]
Critics argue Australia lacks a defined renewables share target despite projections showing over 90 % renewables may be required. [5]
Many major economies are similarly delaying or weakening mid-century climate targets, heightening risks of stranded assets and delayed adaptation. [6]
Impacts & Amplifying Risks
High global temperatures are driving more frequent and severe heatwaves, droughts, floods and coral bleaching events. [1]
Marine heatwaves are stressing ocean ecosystems and reducing the ocean’s ability to absorb carbon dioxide. [1]
Climate models warn that each additional degree of warming increases the risk of triggering major tipping points such as ice-sheet collapse or permafrost thaw. [2]
What Needs To Happen Now
Countries must not only update their commitments but implement them rapidly across energy, transport, land and industry sectors. [3]
Accelerating investment in renewable energy, electrification, energy efficiency and storage will be critical. [4]
Adaptation must also scale up to protect vulnerable populations, infrastructure and ecosystems. [1]
Whether the 2020s become a turning point or a lost decade will depend on global cooperation and domestic follow-through. [6]
Conclusion
September’s record-level heat and multi-year forecasts of sustained warming underline that the world remains off-track. [1] [2] [3]
In Australia and beyond, raising ambition and embedding delivery into policy are essential. [5] [6]
The message from scientists and agencies is clear: the signals are flashing red, and the time for action is now.
References
- September Sees Persistently High Land and Sea Surface Temperatures Globally
- Global Climate Predictions Show Temperatures Expected to Remain at or Near Record Levels in the Next Five Years
- Countries’ New Climate Plans to Start Cutting Global Emissions, UN Says
- Only a Third of National Climate Pledges Support Transition Away from Fossil Fuels
- Australia’s 2035 Climate Target Will Strike a Middle Path: Will It Be Sufficient?
- Nations Must Close Huge Emissions Gap in New Climate Pledges and Deliver Immediate Action, or 1.5 °C Lost