Is Western Australia Experiencing More Extreme Heat?

Why this question matters？

In recent years, extreme heat and bushfires in Australia have raised public concern. This project explores whether Western Australia is experiencing more extreme heat compared to other regions.

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Burnt landscape in Western Australia, February 2025.

During a trip to Western Australia in February 2025, I encountered large areas of burnt vegetation caused by bushfires. According to local guides, these fires were strongly linked to extreme heat conditions.

This experience made the impacts of rising temperatures more tangible, raising the question of whether extreme heat events in Western Australia are becoming more frequent or severe over time.

To understand whether Western Australia is becoming more extreme, we first examine the overall temperature trend across Australia.

Australia is getting warmer

A clear pattern emerges: a long-term warming trend across Australia. While temperature anomalies were predominantly negative in the early to mid-20th century, they have shifted to consistently positive values since around the 1980s.

This shift suggests a structural change in the climate system rather than short-term variability, with recent decades not only warmer on average, but also showing greater fluctuations.

However, this national trend alone does not tell us whether Western Australia is experiencing more extreme heat compared to other regions. To answer this, we next focus specifically on Western Australia and compare it with other major states.

Source: Australian Bureau of Meteorology (ACORN-SAT dataset).

These findings are consistent with official observations from the Australian Bureau of Meteorology. The map above shows widespread warming trends across the country since 1970, with most regions experiencing increases in mean temperature.

How does Western Australia compare?

To provide a meaningful comparison, we focus on Western Australia alongside New South Wales, Victoria, and Queensland, which represent major population centres and different climate regions across Australia.

Western Australia follows a broadly similar warming trend to other major Australian states, with no clear evidence of a substantially stronger long-term increase.

Although the highlighted WA curve rises noticeably in recent decades, the same overall pattern can also be seen in New South Wales, Victoria and Queensland. This suggests that Western Australia is part of a broader national warming trend rather than a clear outlier in terms of average temperature change.

However, average trends do not always capture how climate change is experienced in practice. Even if Western Australia does not warm much faster than other states on average, it may still be experiencing more frequent or more severe extreme heat years.

Arid landscape in Kalbarri National Park, Western Australia.

This environment reflects the naturally dry and heat-prone conditions of Western Australia, where ecosystems are particularly sensitive to temperature changes. Such climatic characteristics make the region an important case for examining warming trends and extreme heat events.

To explore this further, the next section focuses on the hottest years in Western Australia.

Are extreme heat events increasing in Western Australia?

The figure highlights the top 10 hottest years in Western Australia based on annual temperature anomalies. Most of these extreme heat years are concentrated in recent decades, particularly after 2000.

This pattern supports the earlier finding that warming has accelerated over time. As temperatures rise more rapidly, extreme heat events are also becoming more frequent. This suggests that climate change in Western Australia is not only reflected in long-term averages, but also in the increasing occurrence of unusually hot years.

Has recent warming become more pronounced?

To examine whether warming has intensified over time, the data were divided into two periods: before 1980 and from 1980 onwards. Instead of comparing average temperatures alone, the rate of change (trend) was calculated for each period.

The results show that the warming trend after 1980 is steeper, indicating that temperatures in Western Australia have been increasing at a faster rate in recent decades. This suggests that warming is not only continuing, but also accelerating over time.

conclusion

Overall, Australia has experienced a clear warming trend over the past century, with temperature anomalies becoming increasingly positive in recent decades.

When comparing Western Australia with other major states, the long-term trend appears broadly similar, with no strong evidence that Western Australia is warming at a faster rate.

However, a closer look at extreme temperature events reveals a different pattern. The most extreme heat years are heavily concentrated in recent decades, suggesting that extreme heat events have become more frequent or more intense over time.

This indicates that while average temperature increases may appear similar across regions, the risk of extreme heat in Western Australia has still increased, which may have important implications for local communities and environmental conditions.

Data Sources

This project uses publicly available climate data from the Australian Bureau of Meteorology (BoM), specifically the ACORN-SAT (Australian Climate Observations Reference Network – Surface Air Temperature) dataset.

The dataset provides high-quality, specific temperature records across Australia and is widely used for climate trend analysis.

Acknowledgements

This project was completed independently by author. All analysis, interpretation, and final decisions were made by the author. AI tools were only used to adjust clarity of writing.

References

Australian Bureau of Meteorology (2025). ACORN-SAT Dataset.
https://www.bom.gov.au/climate/data/acorn-sat/

Australian Bureau of Meteorology (2025). Climate trends and variability.
https://www.bom.gov.au/climate/change/