Arctic sea ice has recorded its smallest winter peak extent since satellite records began 47 years ago, new data reveals.
Provisional data from the US National Snow and Ice Data Center (NSIDC) shows that Arctic sea ice reached a winter maximum extent of 14.33m square kilometres (km2) last week.
This is 1.31m km2 below the 1981-2010 average maximum and 800,000km2 smaller than the previous low recorded in 2017, according to the data.
Dr Julienne Stroeve, a senior scientist at the NSIDC, tells Carbon Brief that such a small winter peak “doesn’t mean a record-low” summer minimum will necessarily follow in September.
But, she adds, it does “continue the overall long-term decline in the ice cover”.
Meanwhile, Antarctic sea ice reached its summer minimum extent earlier this month, with 2025 tying with 2022 and 2024 for the second-smallest summer low on record, the NSIDC says.
The combination of reduced sea ice cover in both the Arctic and Antarctic means that global sea ice extent dwindled to an “all-time minimum” in February this year, according to the Copernicus Climate Change Service (C3S).
Record low
Arctic sea ice extent changes throughout the year. It grows during the winter towards its annual maximum extent – often referred to as its “winter peak” – in February or March. It then melts throughout the spring and summer towards its September minimum.
Using satellite data, scientists can track the growth and melt of sea ice, allowing them to determine the size of the ice sheet’s winter maximum extent. This is a key way to monitor the “health” of the Arctic sea ice.
On 22 March 2025, Arctic sea ice reached its smallest-ever winter peak, according to the NSIDC. At 14.33m km2, this was 1.31m km2 below the 1981-2010 average maximum and 800,000km2 below the previous low, which was recorded in 2017.
The chart below shows Arctic sea ice extent over the satellite era (1978 to the present day). Red indicates the 2025 extent, while shades of blue indicate different years over 1978-2024.
Daily Arctic sea ice extent (in millions of km2) over the satellite era (1978 to present), where lines indicate individual years. This year is shown in red, while darker blues indicate more recent years. The dashed line indicates the record low winter peak. Credit: Carbon Brief
NSIDC senior research scientist Dr Walt Meier told the Press Association:
“This new record low is yet another indicator of how Arctic sea ice has fundamentally changed from earlier decades. But, even more importantly than the record low, is that this year adds yet another data point to the continuing long-term loss of Arctic sea ice in all seasons.”
Freeze season
The growth season for Arctic sea ice kicked off after reaching its summer minimum extent of 4.28m km2 on 11 September last year. This was the Arctic’s seventh-lowest summer low on record.
As temperatures cooled, the NSIDC says that Arctic sea ice grew slowly at the start of October. Ice growth then sped up towards the middle of the month and then slowed again towards its end. The average sea ice extent for October was 5.94m km2 – the fourth lowest on record, according to the NSIDC.
Throughout November, air temperatures over the Arctic Ocean were “mixed”, according to the NSIDC. It says that temperatures were above average from coastal Canada to northern Scandinavia, as well as in the area north of Greenland, but below average over the Beaufort, Bering and Laptev Seas.
Arctic sea ice grew at a steady pace for most of November – mainly in the Kara, Beaufort and Chukchi Seas, as well as Baffin Bay and the Canadian Arctic archipelago. However, in the Hudson Bay – where air temperatures were 1-5C above average – “no appreciable sea ice” formed, according to the NSIDC.
The November extent averaged 9.11m km2, ranking the third lowest in the satellite record and 1.59mkm2 below the 1981-2010 average, the NSIDC says.
December saw above-average air temperatures over “essentially all of the Arctic Ocean”, with a particularly “prominent” area of warmth off the Canadian Arctic archipelago and Greenland, the NSIDC says.
Due to delayed ice growth in the Hudson Bay and low extent in the northern Barents Sea, December Arctic sea ice extent was the lowest in the satellite record at 11.43m km2.
Daily Arctic sea ice extent decreased sharply at the end of January, when the region lost about 0.3m km2 – an area roughly the size of Italy – in less than a week, according to C3S.
It adds that “such a rapid decrease is unusual at this time of year, when sea ice is typically expanding towards its annual maximum”. It points to the “pronounced warm event” over the Greenland Sea and Svalbard region as the reason for the drop.
Dr Rick Thoman – a specialist in the Alaskan climate from the University of Alaska Fairbanks – tells Carbon Brief that the sea ice decrease in late January and early February was partially driven by “separate cyclones producing simultaneous south winds across much of the Barents and Bering Seas”. As winds pushed the ice northwards, “ocean wave action” melted the thin ice at the edge of the ice sheet, he says.
February was marked by slow Arctic sea ice growth, resulting in a record-low February Arctic sea ice extent of 13.75m km2, according to the NSIDC. The organisation adds that daily sea ice growth “stalled” twice in the month, which “helped to contribute to low ice conditions and led to overall ice retreat in the Barents Sea”.
This rapid melt was partially driven by above-average temperatures. Between northern Greenland and the north pole, temperatures reached up to 12C above average, the NSIDC says.
Antarctic melt
At the south pole, Antarctic sea ice has been declining during the southern hemisphere summer. It reached its annual minimum of 1.98m km2 on 1 March.
This summer low ties with 2022 and 2024 for the second-smallest Antarctic extent in the 47-year satellite record, the NSIDC says. It adds that the past four years are the only years on record in which Antarctic sea ice has reached a minimum below 2m km2.
The graphic below shows Antarctic sea ice extent over the satellite era. Red indicates the 2025 extent and shades of blue indicate different years over 1978-2023.
Daily global sea ice extent (in millions of km2) over the satellite era (1978 to present), where lines indicate individual years. This year is shown in red, while darker blues indicate more recent years. The dashed line indicates the record low. Credit: Carbon Brief
The melt season for Antarctic sea ice began with its winter maximum of 17.2m km2 on 19 September 2024.
This was 1.6m km2 smaller than the 1981-2010 average maximum and the second-lowest winter peak on record, according to the NSIDC.
As the southern hemisphere warmed, Antarctic sea ice began to melt. Throughout October, Antarctic sea ice extent continued to rank the second lowest on the satellite record following the record-breaking 2023 season, the NSIDC says.
It adds that “seasonal ice loss was relatively slow during the early part of the month, but the pace picked up substantially during the last week of October, approaching 2023 values”.
By 30 November, Antarctic sea ice was the third lowest on record, tracking higher than the 2023 and 2016 levels for the same date, the NSIDC says.
After a “prolonged period of record to near-record daily lows set in 2023 and 2024”, December 2024 saw Antarctic sea ice loss slow down, with the average rate of decline tracking “well below average”.
By the end of December 2025, Antarctic sea ice extent was roughly in line with the 1981-2010 average, according to the NSIDC.
As a result, it says that “speculation that the Antarctic had entered a new regime of strongly reduced Antarctic sea ice related to oceanic influences, has, at least temporarily, come to an end”.
It adds that sea ice extent was “above average over the western Weddell and Amundsen Seas and slightly below average in the Ross Sea, with near-average extents in other areas”.
Throughout February, Antarctic sea ice continued to melt – especially in the eastern Ross Sea and Amunsden sea, where ice concentration is low, according to the NSIDC.
Global ‘all-time minimum’
With sea ice at or around record lows in both the Arctic and Antarctic, global sea ice extent dropped to an “all-time minimum” in February this year, according to the Copernicus Climate Change Service (C3S).
Global sea ice hit a new daily low in early February and remained below the previous record from 2023 for the rest of the month, C3S says.
The graphic below shows global sea ice extent over 1978-2025, where red indicates the 2025 extent and shades of blue indicate different years.
Daily Antarctic sea ice extent (in millions of km2) over the satellite era (1978 to present), where lines indicate individual years. This year is shown in red, while darker blues indicate more recent years. The dashed line indicates the record low. Credit: Carbon Brief
C3S deputy director Dr Samantha Burgess noted that the low sea ice came as “February 2025 continues the streak of record or near-record temperatures observed throughout the last two years”. She added:
“One of the consequences of a warmer world is melting sea ice – and the record or near-record low sea ice cover at both poles has pushed global sea ice cover to an all-time minimum.”
The story was picked up in newspapers around the world, including the Guardian, Hindustan Times and Washington Post.
In response to the news from C3DS, Prof Richard Allan – a professor of climate science at the University of Reading – warned that “the long-term prognosis for Arctic sea ice is grim”. He added:
“Averaging over all regions the global warming trend is clear, with February 2025 more than 1.5C above pre-industrial conditions, repeating a level of excess warmth experienced in all but one of the past 20 months despite a weak cooling influence of La Niña conditions in the Pacific.”
The post Arctic sea ice winter peak in 2025 is smallest in 47-year record appeared first on Carbon Brief.
Arctic sea ice winter peak in 2025 is smallest in 47-year record
Scientists have vowed to keep working on the next flagship set of reports for the Intergovernmental Panel on Climate Change (IPCC), after a political row over the timeline for their release saw its latest session suspended on Friday evening without agreement.
During the weekend, government officials and scientists alike expressed disappointment over the inability to reach a compromise before some delegates from developing countries and small island states had to leave the week-long meeting in Ethiopia to catch flights home.
The disagreement – which has persisted since early 2024 – turns on whether the three key parts of the AR7 assessment should all be published before the conclusion of the UN’s next Global Stocktake of global climate action, which is due to be completed in late 2028.
The IPCC issued a statement after the close of the session, saying that “key agenda items” – the timelines for the three AR7 reports, as well as the IPCC budget – remain open and under discussion. It said the IPCC’s plenary session and its deliberations on the pending agenda “will resume at the earliest opportunity”, giving no further details of when.
IPCC Chair Jim Skea told delegates in closing remarks that recent months had been some of the most turbulent for the climate science panel and that, if there were stronger words than “profound disappointment” he would use them, according to a summary published by the Earth Negotiators Bulletin (ENB). IPCC discussions happen behind closed doors.
IPCC scientists remained committed
In an open letter, issued on Monday, a group of nearly 120 scientists – from a total of 664 AR7 authors – said they “stand committed to continue working to deliver the AR7 reports in a manner that is rigorous, timely and inclusive, in line with our mandate to be policy-relevant”.
“An assessment that arrives after the decisions it is meant to inform cannot serve its purpose,” they emphasised. “The second Global Stocktake in 2028 is such a decision point, and the world should not have to face it without the IPCCʼs latest assessment.”
Europe, small islands and the least developed countries, plus many Latin American and developed nations, want the IPCC to meet this deadline, arguing that the findings from the UN climate science body are irreplaceable in the UN climate policy-making process.
However, around a dozen developing countries plus Russia have argued that the reports should come later in order to allow for greater research input from the Global South – something that, in their view, would make the findings fairer. They also claim that a shorter timeline would put excessive pressure on experts.
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Early completion of the next global climate science assessment reports risks excluding research from the Global South, which is key to ensuring the findings are fair -
Governments that support climate science must stand firm against naysayers
The IPCC is meeting to decide the timing of its next major report, as some countries try to delay it and weaken the case for faster emissions cuts
The most vocal of this group at last week’s meeting were India and Saudi Arabia, according to the ENB summary and a developed country diplomat. Critics see this push for a longer timeline as an excuse to deprive government decision-makers of the latest science and ease pressure on emerging economies to raise their ambition, particularly on cutting emissions.
Commenting on last week’s meeting, France’s ambassador for climate negotiations Benoît Faraco said a broad coalition of developed and developing countries from all five continents, “united in their support for science and the timeline proposed by scientists”, had withstood pressure “from a few countries” seeking to slow down the process of adopting the IPCC reports.
He added that France would not back down and would “continue to fight tirelessly for science, protect the integrity of information, and convince our partners that without the best available scientific data, we will be less effective in tackling climate change and protecting our populations”.
Inclusivity proposal stalled
In a bid to unlock a solution for the AR7 timeline, countries discussed ways to improve the inclusivity of the IPCC’s work. One option put on the table was for the IPCC to expand its funding for delegates from developing countries to attend some or all of its sessions from one to two participants, according to the ENB summary and a delegate speaking to Climate Home News.
That would increase the costs for the IPCC to complete AR7 by up to a quarter, according to an assessment shared by the secretariat. The panel’s budget is under severe strain and its officials have warned that, without additional voluntary contributions, it risks running out of money before it can deliver on this assessment cycle.
Climate Home News understands that some of the IPCC’s traditional donors – which mainly include European countries, Japan and Australia – indicated a willingness to support funding for an additional developing country participant. But without an agreement over the budget or the timeline for the reports, that option was ultimately not adopted.
‘Disappointed and worried’
The three reports are managed by working groups that collate and draw overall findings from the latest scientific studies and data on the physical effects of global warming around the world, how to adapt to it, and pathways for cutting planet-heating emissions in order to meet the temperature goals of the Paris Agreement.
Winston Chow, an urban climate professor at Singapore Management University who co-chairs Working Group II on adaptation, wrote in a LinkedIn post that he was “disappointed and worried” for the IPCC authors who have worked “extraordinarily hard” to assess the relevant climate science over the past two years.
He said he shared their concern that “the rigour, time and goodwill they’ve invested are now being put at risk by the Panel’s stalemate”.
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For Working Group II, a meeting for 250 experts writing that report is scheduled for January 2027, followed by the approval of a special report on cities and climate change in Singapore next March.
But because the IPCC’s budget has not been confirmed due to uncertainty about the AR7 schedule, travel support for those researchers is at risk, wrote Chow. “If they cannot participate, our assessments will lose vital expertise, perspectives and scientific breadth, and the collective effort of our authors will be undermined,” he warned.
Scientific work continues
Despite the political holdups, he – together with French climate scientist Robert Vautard, co-chair of Working Group 1 – agreed with IPCC head Skea who told the IPCC’s closing session on Friday: “The engine room of the IPCC is working, and it’s healthy.”
Vautard commented in a separate post on LinkedIn after it ended: “The boat is at full steam.” Working groups I and II are due to start revising the first drafts of their reports, while Working Group III on reducing emissions is finalising its first draft which will be out soon, he wrote.
“The most exciting two years of the cycle are ahead, for the authors. The momentum in the engine room is here and now. Trust the engine room!” he added.
The IPCC and some scientists report that progress has been made towards achieving an equitable balance of authors from the Global North and the Global South.
The group of researchers who signed the open letter on Monday noted that “inclusivity is at the heart of how we work”, with author teams bringing together experts from developed and developing countries with diverse backgrounds and at different stages of their careers.
Plea to overcome political differences
The signatories include several scientists from some of the countries opposed to the alignment of all IPCC reports with the Global Stocktake.
“We are committed to an assessment in which the knowledge, experience and priorities of every region are fully reflected, a commitment we share with the leadership of the IPCC.
Equity is built into how our assessment is being drafted,” they added.
They appealed to governments that make up the IPCC “to overcome their political differences and work together as we do as a global scientific community, so that we can deliver the IPCC reports the world needs to hear”.
In a statement published on Monday, IPCC chair Skea said reaching consensus on the schedule for the reports is “vital”. He added that the assessments provide authoritative scientific evidence to inform national climate policies, strengthen adaptation and resilience and support access to climate finance, as well as helping communicate the scale of the climate crisis and the urgency of efforts to tackle it.
The post IPCC scientists vow to press on with climate reports despite political deadlock appeared first on Climate Home News.
IPCC scientists vow to press on with climate reports despite political deadlock
An Lambrechts is a biodiversity politics expert at Greenpeace International with extensive experience in biodiversity-related multilateral negotiations. She is the head of the Greenpeace delegation at the Convention on Biological Diversity (CBD) COP17 happening in Yerevan, Armenia.
In 2022, COP15 delivered the landmark Kunming-Montreal Global Biodiversity Framework to halt and reverse biodiversity loss by 2030. With COP17 starting in Yerevan, we are now halfway to the deadline, and according to the first Global Review of progress, countries are not on track to meet the biodiversity targets, and implementation must accelerate fast.
One of the main findings of the Global Review is that funding falls far short of the scale needed to halt and reverse nature loss. But the crisis facing the world’s biodiversity is not an absolute scarcity of capital – it is a profound public policy distortion.
The global economy currently spends roughly $30 destroying nature for every single dollar invested in its protection. According to a report from the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services, a staggering $2.4 trillion is spent in public subsidies for fossil fuels, agriculture and water use, while global investment in biodiversity conservation and restoration stands at a mere $220 billion.
Countries urged to ramp up “insufficient” nature policies at COP17
Yet, discussions about how to close the biodiversity finance gap continue to claim that salvation lies in mobilising private capital, scaling offsets and “derisking” investments in nature. This is a fundamental misunderstanding of both the nature of ecological stewardship and of the global financial architecture.
Biodiversity conservation is not a speculative investment portfolio – it is the foundation of human survival. The health of our planet is a non-monetisable, non-excludable public good. Expecting profit-seeking private capital to protect nature perpetuates the structural drivers of ecosystem destruction in the first place.
But if private market mechanisms cannot save biodiversity, where will the necessary public resources come from?
Money going to the wrong places
The answer lies in recovering the vast public wealth currently drained by cross-border tax abuse, financial secrecy and corporate impunity. Finance and environment ministers meeting in Yerevan must give a strong political signal that, to avert ecological breakdown, countries need to take swift action to reform global tax rules, eliminate harmful public subsidies and cancel unsustainable sovereign debts for the public revenues to end up where they belong.
Extractive sectors such as industrial agriculture, fishing, timber and mining continue business-as-usual, often heavily subsidised by public treasuries, while voluntary carbon and biodiversity offset markets pose a serious risk to nature conservation. Offset schemes have delivered only a negligible fraction of the funding needed to preserve ecosystems, allowing industries to continue with their destructive business-as-usual practices.