The Greenland ice sheet melt season 2023 is now over and it completes a 27th year in a row in which Greenland has lost ice.
The 2022-23 year saw both very high melt, particularly in July, but also higher than usual rain and snowfall in the late spring and early summer.
The increase in both melt and snowfall are exactly what scientists expect in a warming climate, and although they have tended to balance each other to some extent, Greenland has still ended up losing more ice than it gained.
As in previous years, while very high temperatures hit North America and Europe this summer, Greenland in between was comparably cool and wet. However, this was not enough to stop Greenland losing ice.
Extended snowfalls from October to December 2022 and the late onset of the melt season contributed to a relatively large accumulation of mass on Greenland’s surface. Nonetheless, this could not outweigh the losses by surface melting and breaking off of icebergs.
Overall, Greenland’s ice sheet lost 196 billion tonnes (Gt) of ice over the 12 months from September 2022 to August 2023.
This means that the last year to see a net gain of ice is still 1996.
In this annual guest post, we discuss the processes of ice sheet melt, glacier “calving” and the weather and climate that explain these losses.
(See our previous annual analysis for 2022, 2021, 2020, 2019, 2018, 2017, 2016 and 2015.)
Surface melt
Greenland’s annual cycle covers the 12 months up until the end of August.
The pattern sees the ice sheet largely gain snow from September, accumulating ice through autumn, winter and into spring. Then, as the year warms up into late spring, the ice sheet begins to lose more ice through surface melt than it gains from fresh snowfall, generally from the end of June. This melt season usually continues until the middle or end of August.
The snow gains and ice losses at the ice sheet’s surface over these 12 months are the “surface mass balance” (SMB) of the ice sheet. The SMB consists of gains through snowfall and losses through runoff and evaporation. Therefore, snowfall is the only way for the ice sheet to gain mass.
The data suggest that the Greenland ice sheet ended the year 2022-23 with a total SMB of about 398Gt. This is the 15th highest SMB in a dataset that goes back 43 years and is quite close to the 1981-2010 average.
The past year’s SMB is illustrated in the maps and charts below, based on data from the Polar Portal. The blue line in the upper chart shows the day-to-day SMB. Large snowfall events become visible as “spikes”. The blue line in the lower chart depicts the accumulated SMB, counted from the beginning of the “mass balance year” on 1 September 2022. In grey, the long-term average and its variability are shown. The red line shows the record low year of 2011-12 for comparison.
The map shows the geographic spread of SMB gains (blue) and losses (red) for 2022-23, compared to the long-term average.
Heat over North America and Europe, cool over Greenland
A closer look at the weather and ice sheet changes through the past 12 months reveals some interesting developments.
Early winter began with above-average snowfall on several occasions in September, October, November and December. In late winter, a rather dry period followed, so that the accumulated SMB was close to – and then slightly below – average as melting began.
The most remarkable feature in the evolution of the SMB in 2023 was the extended period of growth in June. At the end of that month, the accumulated SMB was almost 150Gt above average.
The effect of this extra snow meant that the onset of the melt – or “ablation” season was on 29 June – 16 days later than the 1981-2022 median. The ablation season is defined as the first day of three days in a row with an SMB below -1Gt.
As in previous summer seasons, the reason for the comparatively wet and cool spells over the Greenland ice sheet can be found quite far away from Greenland in “blocking” weather patterns.
These high-pressure weather systems have a huge impact on weather extremes. Strong persistent blocks over North America and Europe were present in the end of May and the first decade of June and at the end of August. The last of these caused catastrophic rainfall in Greece and Libya.
In such a blocked flow, the jet stream is shaped like the Greek capital letter Omega (Ω). Research suggests that such patterns in recent years have been stronger and more persistent. With the jet stream bulging up to the north over Canada and northern Europe, troughs of low pressure are found at each “foot” of the omega – including over Greenland.
The map below shows an example of the recurring circulation patterns, bringing cool weather over Greenland (blue shading) along with high temperatures over Canada and Europe (red shading).
The melt season that followed was stronger than average – even comparable with the record years of 2012 and 2019 – with melting over more than 50% of the ice sheet for 29 days in a row, from 27 June to 25 July.
And while the world was rightly focused on other extreme weather events this summer, the Greenland summer also saw its own record-breaking conditions.
The station at the summit of Greenland – about 3,000 metres above sea level – recorded a new average temperature record of -7.3C, almost 2C warmer than the previous record of -9.2C set in 2012 and 4C warmer than the long-term average at summit station.
Melt season
There were two main melting periods of the ablation season. Despite the cool start, as the melt season got underway there was a period of very high temperatures at the end of July. This brought intense melt all around the ice sheet that led to very large ice losses over a few days.
The map on the left side shows the area of ice melt on 10 July when the maximum melt extent (67%) of this summer (shaded in red) was reached. The centre map shows the second melt maximum (50%), which peaked on 23 August, and finally the map on the right depicts the situation at the end of the season on 31 August. Melting was above average from 21 June through to – and beyond – the end of the season.
Components of the mass balance
The SMB is just one component of the “total” mass mass balance (TMB) of the Greenland ice sheet:
TMB = SMB + MMB + BMB
Here, MMB is the “marine” mass balance, consisting of the breaking off – or “calving” – of icebergs and the melting of the front of glaciers where they meet the warm sea water. BMB is the “basal” mass balance, which refers to ice losses from the base of the ice sheet. This makes a small, but non-zero, contribution to the TMB and mainly consists of frictional effects and the ground heat flux.
The figure below shows the components of the TMB (red) going back to 1987, which includes the SMB (blue), MMB (green) and BMB (orange). These estimates are based on the modelling approach set out in Mankoff et al in 2021.
For the past year, the TMB clocked in at a loss of 196Gt of ice. This means that 2022-23 was the 27th year in a row where the Greenland ice sheet has lost mass overall. As the chart shows, Greenland last saw an annual net gain of ice in 1996.
The only way for the ice sheet to gain ice is via the SMB – that is, through snowfall. The other components, MMB and BMB, are always negative, so the surplus of snowfall over runoff and the two other components needs to be large enough to compensate.
Using data from the GRACE satellites, we can estimate the TMB independently. The distance of these twin satellites changes slightly due to tiny gravity differences caused by mass changes. Expressing these distance differences as mass changes is not straightforward, however, which is the reason why GRACE data are only made available a few months later.
Furthermore, using satellites, we can measure the speed at which ice flows through control points on the ice sheet where we know the thickness and shape of the ice. Thus, we can estimate MMB, the amount of ice being lost by the process of calving and submarine melting. This data is openly available, allowing us to monitor the whole ice sheet budget.
The map and graph below show the gain (blue) and loss (red) in the mass of ice. The difference in these mass changes over a glaciological year (September-August) is the TMB of the ice sheet for that particular year.
The map shows that most of the loss of ice occurs along the edge of the ice sheet, where independent observations also indicate that the ice is thinning. High up in central Greenland, there is a small increase in the mass of the ice – most likely due to a small increase in snowfall, as we would also expect in a warming climate.
The graph illustrates the month-by-month development in changes of mass measured in gigatonnes, relative to April 2002. The left axis on the graph shows how this ice mass loss translates into a sea level rise contribution, where 100Gt corresponds to 0.28mm of global sea level rise.
The two approaches to calculating TMB have a common period of 1 April 2002 to 31 March 2023. These estimates suggest that the Greenland ice sheet lost around 4,578Gt (Mankoff et al.) to 4,745Gt (GRACE) of ice over this time. Note that the two methods are completely independent.
The result from both datasets is equivalent to around 13mm of global average sea level rise. Recent research suggests that the imbalance of the Greenland ice sheet caused by climate change means it is committed to contributing at least 274mm to global sea levels in future, regardless of 21st-century climate pathways.
The post Guest post: How the Greenland ice sheet fared in 2023 appeared first on Carbon Brief.
Climate Change
‘Ride the wave of momentum’: Australia announces once-in-a-decade Marine Parks Network review
In response to the federal government announcing its once-in-a-decade review of Australia’s Marine Parks Network, the following lines can be attributed to Elle Lawless, Senior Campaigner at Greenpeace Australia Pacific:
“Greenpeace Australia Pacific welcomes today’s announcement that the Albanese Government will review Australia’s Commonwealth Marine Parks Network. This is a rare, once-in-a-decade opportunity to strengthen our marine parks and ban industrial fishing in Australia’s marine protected areas.
“Australians would be appalled to know that more than half of Australia’s Marine Parks Network currently allows for extractive industries, like longlining, bottom trawling and oil and gas mining. These so-called ‘protected’ areas were designed to safeguard our beloved ocean wildlife and underwater ecosystems – that is what Australians expect. Damaging industrial industries should not be given a free pass to trawl, fish, drill or extract from our marine parks.”
“With the first Ocean COP just around the corner, and off the back of Australia’s move to ratify the Global Ocean Treaty earlier this year, the Australian government has a unique opportunity to ride the wave of this momentum and solidify itself as a true global ocean leader.
“Greenpeace Australia Pacific is calling for industrial activities to be banned from our protected waters and for at least 30% of Australia’s ocean to be protected as ocean sanctuaries. This review presents a rare opportunity to create more ocean sanctuaries, true blue havens where ocean life can recover, thrive and repopulate the surrounding waters.”
—ENDS—
‘Ride the wave of momentum’: Australia announces once-in-a-decade Marine Parks Network review
In recent days, prominent climate sceptics and rightwing commentators have shared charts on social media incorrectly implying that Europe is having its “quietest” year for wildfires in 2026.
These include Dr Matthew Wielicki, a former University of Alabama geochemist and self-described “professor in exile”, who was recently appointed by the Trump administration to lead the US Global Change Research Program.
However, these charts paint a misleading picture as they are skewed by encompassing the entirety of Russia in the data – including the vast plains of Siberia.
These charts also use data that include fires that are deliberately lit to manage cropland, which is a declining practice across much of Europe.
In this factcheck, Carbon Brief shows that the area burned by wildfires across the European Union in 2026 is second only to 2022 for this time of year.
The latest data from the European Forest Fire Information System (EFFIS) also shows that France has set a new modern record for area burned and Spain’s wildfire season is among the worst on record.
The fires have displaced more than a third of a million people across south-western Europe, while an impending heatwave has also raised fears of the fires worsening in the coming days.
‘Quietest year’
On 27 July, as wildfires raged across multiple European countries, former Conservative peer and climate-sceptic commentator Matt Ridley posted on Twitter that “2026 is the quietest year for wildfires in Europe by some distance”.
Ridley, who sits on the academic advisory council of the Global Warming Policy Foundation (GWPF), a UK-based climate-sceptic lobby group that refuses to reveal the sources of its funding, was responding to an article by Daily Telegraph columnist Tim Stanley.
Stanley’s column, headlined: “Climate change is real – and the right needs to get serious about it”, warned:
“This is no longer a matter of speculation: the wildfires of Europe, pitiless and persistent, are the way we live now.”
Ridley included a chart from Our World In Data, showing the cumulative area burned by wildfires by week for Europe. The chart puts 2026 as having the smallest area for this time of year in a dataset going back to 2012.
Ridley’s post was widely shared by prominent rightwing figures – including Richard Tice, deputy leader of the hard-right, climate-sceptic Reform UK party, former Conservative cabinet minister Jacob Rees-Mogg and multiple commentators.
Separately, Wielicki also shared a chart on Twitter to imply that wildfires in Europe are declining. Wielicki has previously claimed that the “science is not settled on climate change”.
The charts posted by Ridley and Wielicki both use data from the Global Wildfire Information System (GWIS). The GWIS category for “Europe” encompasses all the countries on the continent and includes the whole of Russia.
As a result, Russia accounts for about 74% of the area included in the GWIS definition of “Europe”.
Wildfires in Russia typically account for 80-90% of the burned area in the GWIS Europe dataset. In 2026, fires in Russia are substantially below average. Therefore, including Russia in this comparison creates the false impression that wildfire activity across Europe is unusually low.
Dr Calum Cunningham, a research fellow at the University of Tasmania’s Fire Centre, says that such claims are “highly misleading”, noting that “they rely on aggregating fire activity across an enormous and climatically diverse region”. He tells Carbon Brief:
“A relatively quiet season in Russia can easily mask an exceptionally active season in France or Spain. If the analysis is focused on the regions actually experiencing the current fires, the picture is very different.
“The reality is that western Europe has experienced an extraordinary sequence of climate conditions this year.”
In contrast, the EFFIS provides a subset of wildfire data specifically for the area covered by the 27 nations of the EU, which, therefore, excludes Russia.
Another difference between the two datasets is that GWIS monitors all fires – including those on agricultural land that are intentionally set alight. The burned area as measured by GWIS contains significant cropland area.
By contrast, EFFIS uses land-cover data and other information to filter specifically for forest fires.
Looking at the EU-only data from EFFIS reveals that Europe is far from having its “quietest” year. The bloc’s burned area, as of 29 July, is almost 435,000 hectares (ha) – second only to 2022 for this time of year.
Notably, Wielicki has actually continued to post charts based on GWIS data, even after acknowledging that “includ[ing] all of Russia, including vast areas of Siberia…isn’t a good proxy for Europe”.
French fires
Even looking at EU-wide data misses the scale of this year’s wildfires for some individual countries.
The chart below shows the surge in burned area in France since mid-July.
For much of the first half of the year, the country was having a wildfire season that was only slightly above average in terms of total burned area. However, a notable uptick began in the first week of July.
The third week of the month saw France break its previous cumulative annual record by more than 19,000ha. That gap has widened as the fires continue to burn; as of 29 July, the cumulative burned area in France during 2026 was nearly 24,700ha above the previous record.
The fires in France follow a record-breaking June heatwave that “dried out vegetation across the region, allowing fires to spread quickly”, wrote the New York Times.
On 27 July, French president Emmanuel Macron called a “crisis cabinet meeting” in order to address the fires “ravaging several areas of south-west France”, said France 24.
More than 220,000 people have been evacuated due to the Gironde fire, west of Bordeaux, in “what may be France’s largest peacetime evacuation”, reported the Associated Press.
In the Conversation, Cunningham and two other University of Tasmania researchers write that evacuation orders “protec[t] human lives, but makes it more likely houses and other structures will burn if there’s no one to defend them”. They add:
“There is little doubt climate change has made France and Spain’s wildfires worse. They represent yet another reason to redouble our efforts to tackle climate change and stabilise our climate.”
Central Spain scorched
While Spain’s fire season has not broken records in the same way that France’s has, it is on track to be among the worst since EFFIS began reporting data in 2006.
The chart below shows the rapid increase in burned area in Spain since 8 July. The latest data from EFFIS reveal that, as of 29 July, Spain has almost matched its previous record at this point in the year. It is also nearly five times the average area burned for this time of year.
In Spain, the wildfires have been concentrated in the central part of the country, near Madrid.
BBC News reported that the fires outside the capital have burned “an area more than twice as large as the city itself”.
Nearly 90,000 people were forced from their homes in central Spain by the fires, said the Associated Press.
Pedro Sánchez, Spain’s prime minister, called the fires a “painful expression” of climate change.
Meanwhile, the UK, French and Spanish governments have issued joint statements this week in response to the fires. The UK/Spain statement begins:
“This summer’s wildfires demonstrated that climate change was now a national security emergency facing Europe and threatening our way of life.”
Related
The post Factcheck: No, Europe is not having its ‘quietest’ year for wildfires appeared first on Carbon Brief.
Factcheck: No, Europe is not having its ‘quietest’ year for wildfires
The general public often underestimate support for climate action, while overestimating the real-world actions taken by other people to address the problem, according to new research.
The study, published in Nature Climate Change, explores the differences between people’s support for climate change, their behaviour and their assumptions about other people’s behaviour.
It is based on multiple surveys of more than 5,000 people across Germany and the US.
The study expands on previous research on how the general public systematically underestimate the climate commitment of their peers.
The difference between actual and perceived support for climate action among the public is sometimes known as a “perception gap”.
The surveys tested how people’s perceptions of climate attitudes and behaviours relate to their own willingness to contribute and undertake “climate-friendly” actions.
One of the authors tells Carbon Brief that this perception gap is not due to “ignorance or bias”, but because “people are just not good at making good estimations”.
The research also reveals that people’s opinions and behaviours are more “nuanced than previously assumed” and suggests that simply “correcting misperceptions” does not automatically lead to greater climate action.
Measuring climate actions
The study notes that correcting the perception gap is often seen as a “cost-effective” way to promote public engagement and drive action to reduce the intensification and impacts of climate change.
Most studies that explore the perception gap have primarily focused on surveys that have asked people to report their willingness to support climate change.
In other words, researchers have relied upon people saying they would support efforts to tackle climate change, rather than measuring people’s real-world actions, such as financial donations, attending protests or changing their behaviour.
To fill this gap, the researchers behind the new study surveyed a total of more than 5,000 people in Germany and the US over 2024-25. Surveys were split across five different experiments, each focused on public perceptions of climate attitudes and how they relate to individuals’ actual behaviour:
| Experiment | What they did |
| Survey one | Participants were asked if they were willing to donate 1% of their household income to WWF – and then were given the chance to do so. Follow-up questions asked participants to predict how many of their peers said “yes” and how many actually donated to the charity. |
| Survey two | Participants read a constitutional complaint against the German government, led by Greenpeace, which demands for stricter climate policies. They were asked if they were willing to participate as a claimant and/or donate to the cause – and then were given the chance to do so. Follow-up questions asked participants to predict how many of their peers said “yes” and how many went on to support the complaint. |
| Survey three | Participants were requested to complete an online “work for environmental protection task” where the more “pages” they completed resulted in more donations to WWF. They then predicted how many pages their peers completed. Participants also rated their individual behaviours and support for eight climate policies and then estimated the same for other people. |
| Surveys four and five | Participants were split into three groups that were either informed that 4% of participants had donated 1% of their household income to WWF, that “68% were willing to contribute” or given no information. They then had to state whether they were willing to support WWF and then were given the opportunity to do so. |
The authors note that Germany and the US are two of the “top 10 CO2 emitters” and are places where climate action is “especially necessary”. However, they add that the two countries are not reflective of “diverse cultural contexts” and further research is needed across the world.
The perception gap
The researchers find that most of their participants supported climate action, but much fewer actually performed verifiable behaviours.
For example, survey one finds that 37% of participants said they were willing to donate to WWF, yet just 4% did when given the opportunity.
Participants generally overestimated the climate actions of their peers, predicting that 23% of other people donated. Willingness, on the other hand, was slightly underestimated with respondents averaging around 34%.
The results from survey three suggest that this perception gap is likely due to general cognitive processes within the human brain that make accurate estimations about large groups difficult, say the authors.
The chart below shows the actual percentage of people who supported different environmental policies and performed climate-friendly behaviours (blue dots) compared to average predictions from the surveys (red dots).
They reveal a “consistent pattern” where “small proportions were overestimated and large ones were underestimated”, the authors say, driving predictions towards the middle. This phenomenon is known as “regression to the mean”.
In other words, where public support for a policy was high, participants in the survey estimated it was lower than it was. When the support was lower, estimates would be higher.
The study finds that individual and environmental factors played a role in shaping people’s perceptions of their peers’ climate actions, which were distinct from general misestimations.
For example, people who were already involved in climate action, had more frequent climate discussions and consumed more climate-focused news and media predicted a higher proportion of climate support “across the board”.
The results from the fourth and fifth surveys show that knowing the context of other people’s beliefs and behaviour in surveys can impact the attitudes of participants.
Participants that were told that 68% of people were willing to donate 1% of their household income to the WWF were more willing to donate.
In contrast, participants that were told that 4% of people actually donated did not report more willingness to “discuss climate change, sign petitions or donate” than the control group.
However, there was no obvious impact on actual donations for any of the three groups, the study notes.
Lead study author Dr Kevin Tiede, scientific managing director of the Institute for Planetary Health Behaviour at the University of Erfurt, tells Carbon Brief that the findings suggest that “just telling people how many people support climate action is likely not enough to really change something”.
However, Tiede adds that “direct comparability” between people saying they would donate and actually donating is “limited” and that giving people more time to answer and autonomy over where to donate might result in more people taking action.
‘Pluralistic ignorance’
Tiede explains that the study findings demonstrate the existence of “pluralistic ignorance”, where a person believes their own views differ from the majority.
For climate change, this means that the “vast majority of people around the world support climate action, but people considerably underestimate the extent of this support”, the study says.
However, the surveys reveal that pluralistic ignorance “in the climate domain” is more nuanced than previously thought, say the authors.
Prof Madalina Vascleanu, an assistant professor at Stanford University’s Doerr School of Sustainability, who was not involved in the study, tells Carbon Brief that encouraging climate action is complex.
It may take multiple and repeated “attempts” at effective communication, or for people to directly “experience” the “norm” that climate change is widely supported, she says, rather than simply being told.
“Observable” behaviours, such as “identity signalling” – which could involve anything from protesting to vegetarianism – might have more of an impact on encouraging climate action among peers than “private behaviours like donations”, she adds.
The study is a “great addition to the literature”, Vascleanu says, because “correcting” the perception gap did not have an effect on climate-friendly behaviour, as “scholars had previously assumed”. She adds that it has “sparked several new hypotheses” that her “lab is now working on”.
Prof Mauro Bertolotti, associate professor of social psychology at the Università Cattolica del Sacro Cuore, explains that the “attitude-behaviour gap” revealed by the research is a “rather common finding”.
However, he is “sceptical” of the “simplified and abstract” measures, warning that experiment environments often come with “assumptions and expectations” that are different from real life.
As a result, they might not “replicate” the process people go through when choosing to “make a donation to an environmental cause”, he says.
‘Targeted’ communication strategies
The researchers argue that it is more effective to focus on “targeted” communication strategies – encouraging climate-friendly behaviours that aim to reach the majority who already support climate action, rather than trying to convert climate sceptics.
They call for attention to be paid to the attitude-behaviour gap between people saying they support efforts to tackle climate change and following up with real-world climate actions.
The study suggests strategies for decision-makers to reduce the attitude-behaviour gap, such as “facilitating climate-friendly behaviour” with “convenience and subsidies”. They also recommend ensuring environmental policy prioritises fairness to gain visible and widespread public support.
They add that the public would benefit from understanding the “effectiveness and co-benefits” of climate action.
Tiede, K.E. et al. (2026) People systematically under- and overestimate public engagement in climate action, Nature Climate Change, https://doi.org/10.1038/s41558-026-02668-z
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The post Correcting climate ‘misperceptions’ may not boost climate action appeared first on Carbon Brief.
Correcting climate ‘misperceptions’ may not boost climate action
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