Ketil Isaksen
@ketilisaksen.bsky.social
Senior scientist at the Norwegian Meteorological Institute.
Focusing on permafrost thermal dynamics and climate change in the Arctic and European mountain areas. Long-term permafrost monitoring
Focusing on permafrost thermal dynamics and climate change in the Arctic and European mountain areas. Long-term permafrost monitoring
Pinned
Ketil Isaksen
@ketilisaksen.bsky.social
· Aug 18
PNAS
Proceedings of the National Academy of Sciences (PNAS), a peer reviewed journal of the National Academy of Sciences (NAS) - an authoritative source of high-impact, original research that broadly spans...
www.pnas.org
Our latest research investigates the remarkable heatwave that affected part of the Arctic in the summer of 2024. It caused a 1 percent loss in Svalbard's ice, making this region one of the most significant contributors to global sea-level rise last year www.pnas.org/doi/10.1073/...
Reposted by Ketil Isaksen
Record warm conditions continue in the northernmost portions of the #Arctic Ocean, near the North Pole. This anomalous warmth is forecast to continue over the next week or so too.
More graphics: zacklabe.com/arctic-tempe...
More graphics: zacklabe.com/arctic-tempe...
October 18, 2025 at 1:59 PM
Record warm conditions continue in the northernmost portions of the #Arctic Ocean, near the North Pole. This anomalous warmth is forecast to continue over the next week or so too.
More graphics: zacklabe.com/arctic-tempe...
More graphics: zacklabe.com/arctic-tempe...
Reposted by Ketil Isaksen
Jeg tror dette er godt kjent blant alle som jobber med planlegging i Norge: Vi er verst i Europa på å bygge ned natur.
NRK avslører europeisk naturtap: Norge topper verstingliste
www.nrk.no
October 1, 2025 at 4:50 AM
Jeg tror dette er godt kjent blant alle som jobber med planlegging i Norge: Vi er verst i Europa på å bygge ned natur.
Reposted by Ketil Isaksen
Incredible ice loss measured again at #Konkordiaplatz on the #Aletsch #Glacier, home to the thickest ice in the #Alps (still about 800 m!). Yesterday’s survey revealed another –4.6 m of ice gone in just one year. :(
Measurements by @matthias-huss.bsky.social for GLAMOS
Measurements by @matthias-huss.bsky.social for GLAMOS
September 16, 2025 at 1:19 PM
Incredible ice loss measured again at #Konkordiaplatz on the #Aletsch #Glacier, home to the thickest ice in the #Alps (still about 800 m!). Yesterday’s survey revealed another –4.6 m of ice gone in just one year. :(
Measurements by @matthias-huss.bsky.social for GLAMOS
Measurements by @matthias-huss.bsky.social for GLAMOS
Witnessing the rapid and extensive thawing of permafrost in Svalbard is truly impressive but deeply concerning
August 21, 2025 at 4:17 PM
Witnessing the rapid and extensive thawing of permafrost in Svalbard is truly impressive but deeply concerning
Reposted by Ketil Isaksen
"Melting on the Arctic’s Svalbard Islands Shows the Climate Future Is Now" by @bberwyn.bsky.social for @insideclimatenews.org: insideclimatenews.org/news/1908202...
Melting on the Arctic’s Svalbard Islands Shows the Climate Future Is Now - Inside Climate News
The rapid disintegration of glaciers on the islands north of Norway foreshadows a catastrophic future for the Arctic, scientists warn.
insideclimatenews.org
August 20, 2025 at 12:46 PM
"Melting on the Arctic’s Svalbard Islands Shows the Climate Future Is Now" by @bberwyn.bsky.social for @insideclimatenews.org: insideclimatenews.org/news/1908202...
Ice melt records set in 2020 and 2022 were just marginally greater than previous years, but an extreme and long Arctic heat wave last summer, intensified by weather patterns disrupted by climate change, opened a new page in the record books
insideclimatenews.org/news/1908202...
insideclimatenews.org/news/1908202...
Melting on the Arctic’s Svalbard Islands Shows the Climate Future Is Now - Inside Climate News
The rapid disintegration of glaciers on the islands north of Norway foreshadows a catastrophic future for the Arctic, scientists warn.
insideclimatenews.org
August 20, 2025 at 6:01 AM
Ice melt records set in 2020 and 2022 were just marginally greater than previous years, but an extreme and long Arctic heat wave last summer, intensified by weather patterns disrupted by climate change, opened a new page in the record books
insideclimatenews.org/news/1908202...
insideclimatenews.org/news/1908202...
Reposted by Ketil Isaksen
During the summer of 2024, six weeks of record-smashing heat led to a record-obliterating amount of ice melting on the islands of Svalbard in the Arctic.
Unprecedented Arctic heatwave melted 1 per cent of Svalbard's ice
A six-week period of extraordinary heat in 2024 melted 62 gigatonnes of ice on the Arctic archipelago of Svalbard, obliterating all previous melt records
www.newscientist.com
August 19, 2025 at 9:19 AM
During the summer of 2024, six weeks of record-smashing heat led to a record-obliterating amount of ice melting on the islands of Svalbard in the Arctic.
Reposted by Ketil Isaksen
Summer 2024 featured unprecedented warmth in the European Arctic, causing melting of 1 % of the total ice volume on Svalbard.
Bad news is that in 2100 and even in the optimistic SSP1-2.6 emission scenario, 50% of the future summers will be warmer than 2024.
www.pnas.org/doi/10.1073/...
Bad news is that in 2100 and even in the optimistic SSP1-2.6 emission scenario, 50% of the future summers will be warmer than 2024.
www.pnas.org/doi/10.1073/...
August 19, 2025 at 6:21 AM
Summer 2024 featured unprecedented warmth in the European Arctic, causing melting of 1 % of the total ice volume on Svalbard.
Bad news is that in 2100 and even in the optimistic SSP1-2.6 emission scenario, 50% of the future summers will be warmer than 2024.
www.pnas.org/doi/10.1073/...
Bad news is that in 2100 and even in the optimistic SSP1-2.6 emission scenario, 50% of the future summers will be warmer than 2024.
www.pnas.org/doi/10.1073/...
Reposted by Ketil Isaksen
Shocking stats from this paper on the extreme 2024 summer heat in Arctic Svalbard, which lost 1% of its total ice volume in just ~6 weeks. 🔥
In fact, Svalbard's 2024 glacier mass loss actually exceeded that of the Greenland Ice Sheet, which is 50 times larger!!! 😱
www.pnas.org/doi/10.1073/...
❄️🧪🌊
In fact, Svalbard's 2024 glacier mass loss actually exceeded that of the Greenland Ice Sheet, which is 50 times larger!!! 😱
www.pnas.org/doi/10.1073/...
❄️🧪🌊
August 19, 2025 at 10:26 AM
Shocking stats from this paper on the extreme 2024 summer heat in Arctic Svalbard, which lost 1% of its total ice volume in just ~6 weeks. 🔥
In fact, Svalbard's 2024 glacier mass loss actually exceeded that of the Greenland Ice Sheet, which is 50 times larger!!! 😱
www.pnas.org/doi/10.1073/...
❄️🧪🌊
In fact, Svalbard's 2024 glacier mass loss actually exceeded that of the Greenland Ice Sheet, which is 50 times larger!!! 😱
www.pnas.org/doi/10.1073/...
❄️🧪🌊
Reposted by Ketil Isaksen
2024 glacier loss in Svalbard was beyond imagination! 😱
- Anomaly of up to 4 SD!
- Amounts to ~61.7 Gt => 1% of the total ice volume
- Comparable to that of the Greenland ice sheet (55 Gt), which is 50 x larger!
... Otherworldly! 🪐
www.pnas.org/doi/10.1073/...
- Anomaly of up to 4 SD!
- Amounts to ~61.7 Gt => 1% of the total ice volume
- Comparable to that of the Greenland ice sheet (55 Gt), which is 50 x larger!
... Otherworldly! 🪐
www.pnas.org/doi/10.1073/...
Svalbard’s 2024 record summer: An early view of Arctic glacier meltdown? | PNAS
A record-breaking melt season affected the Arctic glaciers of Svalbard in summer 2024
by a substantial margin. Across the entire archipelago, glaci...
www.pnas.org
August 19, 2025 at 9:57 AM
2024 glacier loss in Svalbard was beyond imagination! 😱
- Anomaly of up to 4 SD!
- Amounts to ~61.7 Gt => 1% of the total ice volume
- Comparable to that of the Greenland ice sheet (55 Gt), which is 50 x larger!
... Otherworldly! 🪐
www.pnas.org/doi/10.1073/...
- Anomaly of up to 4 SD!
- Amounts to ~61.7 Gt => 1% of the total ice volume
- Comparable to that of the Greenland ice sheet (55 Gt), which is 50 x larger!
... Otherworldly! 🪐
www.pnas.org/doi/10.1073/...
Our latest research investigates the remarkable heatwave that affected part of the Arctic in the summer of 2024. It caused a 1 percent loss in Svalbard's ice, making this region one of the most significant contributors to global sea-level rise last year www.pnas.org/doi/10.1073/...
PNAS
Proceedings of the National Academy of Sciences (PNAS), a peer reviewed journal of the National Academy of Sciences (NAS) - an authoritative source of high-impact, original research that broadly spans...
www.pnas.org
August 18, 2025 at 10:59 PM
Our latest research investigates the remarkable heatwave that affected part of the Arctic in the summer of 2024. It caused a 1 percent loss in Svalbard's ice, making this region one of the most significant contributors to global sea-level rise last year www.pnas.org/doi/10.1073/...
This July reminded us that in the north, heat is not a distant threat but is seeping into hospitals, care facilities & homes. Our infrastructure was not built to withstand these extreme temperatures and our population is increasingly susceptible to dangerous heat www.theguardian.com/environment/...
‘No country is safe’: deadly Nordic heatwave supercharged by climate crisis, scientists say
Historically cool nations saw hospitals overheating and surge in drownings, wildfires and toxic algal blooms
www.theguardian.com
August 14, 2025 at 7:47 AM
This July reminded us that in the north, heat is not a distant threat but is seeping into hospitals, care facilities & homes. Our infrastructure was not built to withstand these extreme temperatures and our population is increasingly susceptible to dangerous heat www.theguardian.com/environment/...
Reposted by Ketil Isaksen
Getting used to this image: #glaciers almost completely naked - unprotected by the white snow - in August...
While July was good for glaciers after record-melt in June, the new heat wave again results in major ice loss
@vaw-glaciology.bsky.social
While July was good for glaciers after record-melt in June, the new heat wave again results in major ice loss
@vaw-glaciology.bsky.social
August 11, 2025 at 1:21 PM
Getting used to this image: #glaciers almost completely naked - unprotected by the white snow - in August...
While July was good for glaciers after record-melt in June, the new heat wave again results in major ice loss
@vaw-glaciology.bsky.social
While July was good for glaciers after record-melt in June, the new heat wave again results in major ice loss
@vaw-glaciology.bsky.social
Reposted by Ketil Isaksen
This is unbelievable.
The high temperature at one of Finland’s northernmost weather stations, in the municipality of Sodankylä (Lapland region) within the Arctic Circle at latitude 67.3°N, reached at least 25°C for 26 days in a row.
Records date back to 1908.
The high temperature at one of Finland’s northernmost weather stations, in the municipality of Sodankylä (Lapland region) within the Arctic Circle at latitude 67.3°N, reached at least 25°C for 26 days in a row.
Records date back to 1908.
August 6, 2025 at 4:45 PM
This is unbelievable.
The high temperature at one of Finland’s northernmost weather stations, in the municipality of Sodankylä (Lapland region) within the Arctic Circle at latitude 67.3°N, reached at least 25°C for 26 days in a row.
Records date back to 1908.
The high temperature at one of Finland’s northernmost weather stations, in the municipality of Sodankylä (Lapland region) within the Arctic Circle at latitude 67.3°N, reached at least 25°C for 26 days in a row.
Records date back to 1908.
Reposted by Ketil Isaksen
Inspired by @ketilisaksen.bsky.social post, I did the same analysis for Finland.
In terms of 14-day average temperatures, the 2025 heatwave in Finland did not quite surpass the well-known 1972 and 2018 heatwaves.
This is based on 10 km gridded observations.
In terms of 14-day average temperatures, the 2025 heatwave in Finland did not quite surpass the well-known 1972 and 2018 heatwaves.
This is based on 10 km gridded observations.
August 4, 2025 at 11:18 AM
Inspired by @ketilisaksen.bsky.social post, I did the same analysis for Finland.
In terms of 14-day average temperatures, the 2025 heatwave in Finland did not quite surpass the well-known 1972 and 2018 heatwaves.
This is based on 10 km gridded observations.
In terms of 14-day average temperatures, the 2025 heatwave in Finland did not quite surpass the well-known 1972 and 2018 heatwaves.
This is based on 10 km gridded observations.
Melting glaciers threaten to wipe out European villages - is the steep cost to protect them worth it? www.bbc.com/news/article...
Why glaciers are threatening to wipe out more mountain villages
Switzerland spends almost $500m a year on protective structures. Is it worth it - or, as some suggest, should people move away from the mountain villages at risk?
www.bbc.com
August 3, 2025 at 6:57 AM
Melting glaciers threaten to wipe out European villages - is the steep cost to protect them worth it? www.bbc.com/news/article...
En sommer med ekstremvær www.nrk.no/klima/ekstre...
Ekstremværsommeren 2025
www.nrk.no
August 2, 2025 at 3:06 PM
En sommer med ekstremvær www.nrk.no/klima/ekstre...
Reposted by Ketil Isaksen
Disregarding the extreme and record-low sea-ice extent in Antarctic the last two years, this year's July extent is exceptionally low, ranking as the 3rd lowest on record.
The July extent over the last four years differs significantly from that of the previous four decades.
@osi-saf.eumetsat.int
The July extent over the last four years differs significantly from that of the previous four decades.
@osi-saf.eumetsat.int
August 2, 2025 at 12:15 PM
Disregarding the extreme and record-low sea-ice extent in Antarctic the last two years, this year's July extent is exceptionally low, ranking as the 3rd lowest on record.
The July extent over the last four years differs significantly from that of the previous four decades.
@osi-saf.eumetsat.int
The July extent over the last four years differs significantly from that of the previous four decades.
@osi-saf.eumetsat.int
Nordic countries hit by ‘truly unprecedented’ heatwave www.theguardian.com/environment/...
Nordic countries hit by ‘truly unprecedented’ heatwave
Scientists record longest streak of temperatures higher than 30C in region in records going back to 1961
www.theguardian.com
August 2, 2025 at 2:35 PM
Nordic countries hit by ‘truly unprecedented’ heatwave www.theguardian.com/environment/...
Reposted by Ketil Isaksen
20 straight days with 30 °C in Finland! Truly unprecedented heatwave still in full swing with maximum today about 32-33 degrees.
Even the Arctic regions (e.g. Sodankylä Tähtelä) have seen three weeks above 25 °C, and may rival tomorrow their August heat records.
Even the Arctic regions (e.g. Sodankylä Tähtelä) have seen three weeks above 25 °C, and may rival tomorrow their August heat records.
July 31, 2025 at 8:24 AM
20 straight days with 30 °C in Finland! Truly unprecedented heatwave still in full swing with maximum today about 32-33 degrees.
Even the Arctic regions (e.g. Sodankylä Tähtelä) have seen three weeks above 25 °C, and may rival tomorrow their August heat records.
Even the Arctic regions (e.g. Sodankylä Tähtelä) have seen three weeks above 25 °C, and may rival tomorrow their August heat records.
Reposted by Ketil Isaksen
The heatwave in Finland could last another week or so as the Omega pattern strengthens over northeast Europe.
The persistence of the heatwave will make it definitely one of the strongest on record in Finland, if not the strongest.
The persistence of the heatwave will make it definitely one of the strongest on record in Finland, if not the strongest.
July 27, 2025 at 10:37 AM
The heatwave in Finland could last another week or so as the Omega pattern strengthens over northeast Europe.
The persistence of the heatwave will make it definitely one of the strongest on record in Finland, if not the strongest.
The persistence of the heatwave will make it definitely one of the strongest on record in Finland, if not the strongest.
Temperaturen under den varmeste 14-dagers perioden i juli 2025 er den desidert høyeste som er registrert for Norge
July 30, 2025 at 1:26 PM
Temperaturen under den varmeste 14-dagers perioden i juli 2025 er den desidert høyeste som er registrert for Norge
Reposted by Ketil Isaksen
Melting over 80.6% of the area of the Greenland Ice Sheet. This is the highest value in our data set, which starts in 1981.
@polarportal.bsky.social
@polarportal.bsky.social
July 25, 2025 at 7:58 PM
Melting over 80.6% of the area of the Greenland Ice Sheet. This is the highest value in our data set, which starts in 1981.
@polarportal.bsky.social
@polarportal.bsky.social
Reposted by Ketil Isaksen
Great piece in today's NYTimes on the recent acceleration of global warming (and its impacts), featuring comments from Kate Marvel, Daniel Swain, Cecilia Bitz, and me: www.nytimes.com/2025...
June 26, 2025 at 6:50 PM
Great piece in today's NYTimes on the recent acceleration of global warming (and its impacts), featuring comments from Kate Marvel, Daniel Swain, Cecilia Bitz, and me: www.nytimes.com/2025...