Antarctica’s heatwaves are a warning to humanity – and we have only a narrow window to save the planet Climate scientists

Antarctica’s sea ice levels are plummeting as extreme weather events happen faster than scientists predicted

Antarctica is currently experiencing dramatic changes at unprecedented rates, marked by repeated extreme events. These include circum-Antarctic summer heatwaves and an autumn heatwave last year, with temperatures soaring up to 40C above the average. Moreover, both last summer and this winter, sea ice extent has reached record lows. These changes have happened even faster than scientists predicted.

These changes coincide with a broader global pattern of extreme air and sea surface temperatures, wildfires, floods, disease and other events deeply impacting ecosystems and society. Scientists have warned society about global climate change and its impacts since the Intergovernmental Panel on Climate Change’s first report in the early 1990s. The Antarctic community has done so repeatedly too. These warnings are now being realised.

Antarctica is a crucial component of the Earth system and a sentinel for growing change. As Antarctic scientists, we see the evidence of mounting change, including changes in food webs, rapid change in populations, breeding failure and local ecosystem collapse, with projections of rapid transformation of a region that makes our planet liveable and contributes in extraordinary ways to global biodiversity.

This is a critical moment, impacting our well-being, future generations and ecosystems globally. Confronted by this evidence, we urgently call on nations to intensify and exceed their current commitments to greenhouse gas emissions reductions. An immediate increase in ambition is required to reach net zero and to go beyond it. Pledges are not enough.

The events unfolding in Antarctica have not been restricted to the continent. Record after record has been broken over the past few years for heatwaves, wildfires, floods and droughts across the globe. Diseases such as avian influenza (H5N1 bird flu), which has touched 81 countries over the last two years, also pose significant threats. The IPCC and the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services have reported change across the planet, impacting society, infrastructure, populations, species, ecosystems and the natural world on which humans are entirely dependent.

Simultaneous changes in the Antarctic and Southern Ocean, and elsewhere around the globe, reflect the intimate connection between Antarctica and the rest of the Earth system. Our lives and our future depend on a healthy and functioning Antarctica. As a result, Antarctica’s unsettling changes provide a warning to us and an opportunity. That opportunity rests in recognising that, if we safeguard Antarctica, if we slow down change there and eventually stop it, we help provide a future for ourselves, our families and our livelihoods. Doing so requires political will and the engagement of civil society. But it also demands the contributions of scientists to help us face what is coming, to understand the consequences of our actions, to develop new approaches for mitigating and adapting to change, and to help us understand the risks we face and over what timescale. It is clear that the community of biologists meeting in Ōtautahi Christchurch is doing what it can, and is standing ready to do more. They hope that political leaders will listen to them and take action.

During a recent gathering of experts from over 20 countries in Ōtautahi Christchurch, a multitude of attendees unveiled groundbreaking findings, pointing to remarkable transformations within Antarctic species, populations and ecosystems. These revelations were accompanied by expressions of genuine concern and, in some instances, astonishment at the rapidity of these system-wide responses.

The Scientific Committee on Antarctic Research’s (Scar) biology symposium was enriched by addresses by Sir Tipene O’Regan and Dr Michael Stevens, noted Māori historians, of Ngāi Tahu who both emphasised the importance of Māori historical connection with the Southern Ocean as well as concerns and aspirations for its future.

The scope of the unusual occurrences in Antarctica extends beyond just biological systems. Other records have been shattered, with this year witnessing sea ice levels plummeting to unprecedented lows according to the satellite record. Last year an alarming, widespread heatwave hit large areas of Antarctica, causing, at some locations, a 35-40C temperature rise above long-term averages. Extreme temperature events have been observed in various other parts of the continent, including the Antarctic peninsula.

As the symposium conference unfolded and the research findings were laid bare, a sense of apprehension permeated the scientific community present. In response to the emerging data, the attending scientists felt compelled to issue a collective communique, expressing deep-seated concerns regarding the escalating environmental challenges unfolding across the Antarctic continent.

We have a narrow window for change. Events in the Antarctic we have observed and catalogued, and the projections from our research suggest that the window is closing fast.

The time for critical action is right now. What we do today will determine our future for centuries. We all deserve a brighter future. Together, we can make a difference.

• This op-ed is an edited version of a communique from the Scar biology symposium by Prof S Craig Cary, University of Waikato, Prof Steven Chown, Monash University, distinguished Prof Sharon Robinson AM, University of Wollongong, Dr Charles Lee, University of Waikato, assistant Prof Cassandra Brooks, University of Colorado Boulder

Last year an alarming, widespread heatwave hit large areas of Antarctica, causing, at some locations, a 35-40C temperature rise above long-term averages. Photograph: Terrance Klassen/Alamy