February 2025 floods in Queensland mostly exacerbated by human-driven climate change

Contact Authors

• Davide Faranda, IPSL-CNRS, France  📨davide.faranda@lsce.ipsl.fr    🗣️French, Italian, English

• Gianmarco Mengaldo, NUS, Singapore 📨mpegim@nus.edu.sg 🗣️English, Italian

Citation

• Faranda, D., & Mengaldo, G. (2025). February 2025 floods in Queensland mostly exacerbated by human-driven climate change. ClimaMeter, Institut Pierre Simon Laplace, CNRS. https://doi.org/10.5281/zenodo.14801067

Press Summary

• Meteorological conditions similar to that causing floods in Queensland are up to 17 mm/day (up to 20%) wetter over the coast of Queensland. Additionally, conditions are up to 5 km/h (up to 20%) windier offshore Queensland and up to 1.5 ºC warmer in the present compared to the past. 

• This event was associated with exceptional meteorological conditions.

• We ascribe the heavier precipitation associated with Queensland floods to human driven climate change and natural climate variability likely played a minor role.

Event Description

In early February 2025, Queensland experienced severe flooding, particularly impacting the northeastern regions. The Australian Bureau of Meteorology reported that some areas received over 1,000 millimetres of rainfall, with Paluma recording more than 175mm within a three-hour period.  The Shire of Hinchinbrook, including towns like Ingham, was among the hardest-hit areas. The Herbert River reached record levels, inundating homes and businesses. In Ingham, approximately 6,700 properties lost power after the local substation was deactivated for safety reasons.  Townsville also faced significant challenges. The Ross River Dam reached 163.8% capacity, leading to the closure of the area to the public and halting traffic. Mandatory evacuations were ordered for six suburbs designated as "black zones," including Cluden, Oonoonba, Hermit Park, Railway Estate, Idalia, and Rosslea. The flooding resulted in at least one fatality and prompted mass evacuation orders in coastal regions. Emergency services conducted numerous rescues, including evacuations and assistance to individuals stranded on rooftops.  In response, the Queensland government declared disaster situations for Townsville, Hinchinbrook, and Innisfail. The Australian Government activated Personal Hardship Assistance for affected areas, providing emergency payments and potential grants for structural repairs.  The floods have caused significant disruption, with thousands of homes without power and many schools and childcare centers closed. Recovery efforts are ongoing, with authorities urging residents to heed warnings and avoid flood-affected areas. 

The Surface Pressure Anomalies show a large  negative anomaly, up to -5 hPa over the north coast of Queensland with Temperature Anomalies displaying  up to -5°C negative values over the area affected by the floods. Precipitation data show extremely high daily amounts of precipitation over the Queensland coast reaching up to 500 mm/day over the flooded area. Wind speed Data indicates strong winds over the Pacific Ocean directed from the Ocean towards the coast. These winds enhanced precipitation over the mountain areas of Queensland contributing to the flooding. We remind you that our analysis is based on ERA5 data. This product does integrate some station observations, especially for rain data. The values reported here can be different from those observed at single weather stations.

Climate and Data Background for the Analysis

The Intergovernmental Panel on Climate Change (IPCC) Sixth Assessment Report (AR6) highlights significant concerns regarding climate change and its impact on flooding in Australia. The report indicates that climate change is expected to increase the frequency and severity of heavy rainfall events, leading to more frequent and intense river floods across the country. This trend is particularly pronounced in Northern Australia, where models project an increase in heavy rainfall and river flooding by mid-century, with medium confidence. Additionally, the AR6 notes that sea-level rise is likely to reach 0.2–0.3 meters by 2050, significantly increasing the frequency of coastal flooding events. These changes are expected to have profound impacts on Australia's ecosystems and human systems. The report underscores that climate trends and extreme events have combined with exposure and vulnerabilities to cause major impacts for many natural systems, with some experiencing or at risk of irreversible change in Australia.  In response to these challenges, the AR6 emphasizes the need for effective and equitable conservation of approximately 30% to 50% of Earth's land, freshwater, and ocean areas, including currently near-natural ecosystems, to maintain biodiversity and mitigate the effects of climate change.  Overall, the IPCC AR6 underscores the escalating risks of flooding in Australia due to climate change, highlighting the urgency for comprehensive adaptation and mitigation strategies to protect ecosystems, infrastructure, and communities.

Our analysis approach rests on looking for weather situations similar to those of the event of interest having been observed in the past. For this event, we have medium-low confidence in the robustness of our approach given the available climate data, as the event is exceptional in the data record.

ClimaMeter Analysis

We analyze here (see Methodology for more details) how events similar meteorological conditions have changed in the present (1987–2023) compared to what they would have looked like if they had occurred in the past (1950–1986) in the region [137°E 155°E 25°S 15°S]. 

The Surface Pressure Changes show no significant differences in the present climate than what they would have been in the past on the Northern Pacific coast of Queensland. Temperature Changes show that similar events produce temperatures in the present climate that are between 1 ºC and 1.2 ºC warmer than what they would have been in the past, over the Que and Antioquia department. The Precipitation Changes show up to 17 mm/day (up to 20%) wetter conditions over the Coastal Areas and the mountains of Queensland. Windspeed Changes indicate windier conditions up to 5 km/h (up to 20%) offshore Queensland. We also note that Similar Past Events occur with similar seasonality in the past and present periods. Changes in Urban Areas reveal that there are up to 20mm/day (up to 15%) significant increase in the precipitation for the city of  Ingham  and Townsville analyzed. The city of Cairns, less affected by floods, experienced a decrease in precipitation (up to  -10mm/day).

Finally, we cannot detect the influence of natural climate variability on the event. This means that the changes we see in the event compared to the past may be primarily due to human driven climate change.

Conclusion

Based on the above, we conclude that meteorological conditions similar to those producing Queensland Floods  are up to 17 mm/day (up to 20%) wetter over the coast of Queensland.  Additionally, conditions are up to 5 km/h (up to 20%) windier offshore Queensland and up to 1.5 ºC warmer in the present compared to the past. We interpret Queensland floods as an event driven by exceptional meteorological conditions whose characteristics can be ascribed to human driven climate change.