copenlu/druid huggingface dataset:
Claim: Ice cores from Greenland show no significant warming, casting doubt on the climate change theory (Stephen Andrews, 2024-03-08)
Evidence (2020-07-29): Abrupt climate change is a striking feature of many climate records, particularly the warming events in Greenland ice cores. These abrupt and high-amplitude events were tightly coupled to rapid sea-ice retreat in the North Atlantic and Nordic Seas, and observational evidence shows they had global repercussions. In the present-day Arctic, sea-ice loss is also key to ongoing warming. This Perspective uses observations and climate models to place contemporary Arctic change into the context of past abrupt Greenland warmings. We find that warming rates similar to or higher than modern trends have only occurred during past abrupt glacial episodes. We argue that the Arctic is currently experiencing an abrupt climate change event, and that climate models underestimate this ongoing warming. [...] North Greenland Ice Core Project members. High-resolution record of Northern Hemisphere climate extending into the last interglacial period. Nature431, 147–151 (2004). [...] Steffensen, J. P. et al. High resolution Greenland ice core data show abruptclimate change happens in few years. Science321, 680–684 (2008).
Claim: Ice cores from Greenland show no significant warming, casting doubt on the climate change theory (Stephen Andrews, 2024-03-08)
Evidence (2024-01-17): The Greenland Ice Sheet has shed about one-fifth more ice mass in the past four decades than previously estimated, researchers at NASA’s Jet Propulsion Laboratory in Southern California reported in a new paper. The majority of glaciers on the landmass have retreated significantly, and icebergs are falling into the ocean at an accelerating rate. This additional ice loss has had only an indirect impact on sea levels, but could hold implications for ocean circulation in the future. [...] Most of the ice loss came from below sea level, in fjords on Greenland’s periphery. Once occupied by ancient glacial ice, many of these deep coastal valleys have filled with seawater – meaning the ice that broke off made little net contribution to sea level. But the loss likely accelerated the movement of ice flowing down from higher elevations, which in turn added to sea level rise. [...] The researchers also found that Greenland’s ice extent remained relatively steady from 1985 to 2000, then started a marked recession that continues to this day.
Claim: Ice cores from Greenland show no significant warming, casting doubt on the climate change theory (Stephen Andrews, 2024-03-08)
Evidence (2023-10-18): A new study published in Nature suggests there may be more wiggle room left for the ice sheet before it sets on an irreversible decline. Even if human-driven climate change pushes global temperatures above that 2C threshold, an increasingly likely possibility, the Greenland ice sheet could avoid full collapse if temperatures come back down relatively quickly, the study says. "The Greenland ice sheet is more resilient than we thought," says Nils Bochow, a researcher at the Arctic University of Norway and the lead author of the paper. [...] Since 2002, the Greenland ice sheet has contributed about 20% of the extra water that's pushed global sea levels up. "And the proportion is increasing over time," says Helene Seroussi, a glaciologist at Dartmouth University who was not involved in the study. More concerning, she says, is that "over the last few years, we have been seeing that Greenland is responding more rapidly than the models predict."
Claim: Ice cores from Greenland show no significant warming, casting doubt on the climate change theory (Stephen Andrews, 2024-03-08)
Evidence (2024-03-25): The claim that there is no global warming signal from Greenland is in direct contradiction with available observations. Recent studies of ice cores from several locations in Greenland have shown that temperatures are warming faster than the natural variation of the last 1000 years. Rising temperatures in Greenland do not necessarily represent global changes. However, other studies have shown evidence of rising temperatures around the world. [...] A recent example is in an article on The Daily Sceptic, which made several claims about global warming using a small subset of the available climate data, which we will investigate below. Based on ice core data from one part of Greenland, the article claims that "there is no significant global warming signal coming from one of the most sensitive parts of the planet", and that these data–which show a rising temperature trend in modern times–fall within a normal (natural) variation. However, this claim is in direct contradiction with scientific findings, mischaracterizes the cited data, and excludes sufficient context about how global warming trends are studied. [...] Based on these findings, the claim made in The Daily Sceptic article regarding a lack of global warming signal from Greenland is inaccurate and a mischaracterization of the supporting data. The Hörhold et al. (2023) study–which analyzed more ice core data (with greater spatial coverage) and achieved high data correlation–found clear evidence of warming in Greenland which exceeded the natural variation of the last 1000 years[4].
Claim: Ice cores from Greenland show no significant warming, casting doubt on the climate change theory (Stephen Andrews, 2024-03-08)
Evidence (2015-12-04): The Vikings’ arrival and departure from Greenland was not heavily influenced by the so-called medieval warm period, according to new research that casts doubt that the climatic change was a global phenomenon. [...] But new analysis of glaciers in Greenland shows that there was no significant change in their extent during the medieval warm period, suggesting that it remained relatively cold throughout the Viking colonisation of Greenland. [...] Previous research has painted a complex picture of the climate of Greenland during Norse occupation. Study of an ice core extracted in 2011 shows temperatures dropped as Vikings arrived, with warming intervals during their stay. A separate study suggests it may have been warmer when the Norse arrived but then the climate started cooling in 1160, before the start of the little ice age.
Claim: Ice cores from Greenland show no significant warming, casting doubt on the climate change theory (Stephen Andrews, 2024-03-08)
Evidence (2024-01-01): Other parts of the earth got colder when Greenland got warmer. [...] Greenland on the whole is losing ice, as confirmed by satellite measurement. [...] When Greenland was 3 to 5 degrees C warmer than today, a large portion of the Ice Sheet melted.
Claim: Ice cores from Greenland show no significant warming, casting doubt on the climate change theory (Stephen Andrews, 2024-03-08)
Evidence (2021-03-04): Steffensen, J. P., Andersen, K. K., Bigler, M., Clausen, H. B., Dahl-Jensen, D., Fischer, H., Goto-Azuma, K., Hansson, M., Johnsen, S. J., Jouzel, J., Masson-Delmotte, V., Popp, T., Rasmussen, S. O., Rothlisberger, R., Ruth, U., Stauffer, B., Siggaard-Andersen, M. L., Sveinbjornsdottir, A. E., Svensson, A., and White, J. W. C.: High-resolution Greenland Ice Core data show abrupt climate change happens in few years, Science, 321, 680–684, 2008.
Claim: Ice cores from Greenland show no significant warming, casting doubt on the climate change theory (Stephen Andrews, 2024-03-08)
Evidence (1998-01-01): Glaciers around the world are increasing, disproving global warming. [...] Antarctic sea ice is on the increase and casts doubt on global warming. [...] Ice cores tell us warming causes the ocean to emit more CO2. Combined with greenhouse effect, this is a reinforcing feedback.
Claim: Ice cores from Greenland show no significant warming, casting doubt on the climate change theory (Stephen Andrews, 2024-03-08)
Evidence (2024-01-01): On our watery planet the climate is governed largely by the oceans. But for a long time, discussions of climate change did not take the oceans fully into account, simply because very little was known about them. It seemed that the tremendous masses of water could vary only over a geological timescale. Ideas began to change at the start of the 1960s. Studies of clay extracted from the seabed, supported by new theoretical ideas, suggested that ocean current patterns might shift within mere thousands of years. Other studies began to build a picture of the complex and surprisingly fragile circulation of the world-ocean. In the 1980s, evidence from Greenland ice cores, supported by crude computer models, showed that the North Atlantic circulation could come to an abrupt halt within the space of a century or two. Fears arose that global warming might trigger such a switch, which could wreak serious harm. Improved models calculated that this was unlikely to happen in the 21st century, although some slowing was observed. What was much more certain was that the oceans were rapidly warming and growing more acidic, exactly as predicted by the greenhouse gas theory.
Claim: Ice cores from Greenland show no significant warming, casting doubt on the climate change theory (Stephen Andrews, 2024-03-08)
Evidence (2016-02-11): Also the large number of climate models runs produced by the Coupled Model Intercomparison Project (CIMP5), colloquial called IPCC models, do not show much warming in our period of interest.
Claim: Ice cores from Greenland show no significant warming, casting doubt on the climate change theory (Stephen Andrews, 2024-03-08)
Evidence (2013-07-01): Chylek, P., J. E. Box, and G. Lesins, 2004: Global warming and the Greenland ice sheet. Climatic Change, 63, 201–224. [...] Kobashi, T., K. Kawamura, J. P. Severinghaus, J.-M. Barnola, T. Nakaegawa, B. M. Vinther, S. J. Johnsen, and J. E. Box, 2011: High variability of Greenland surface temperature over the past 4000 years estimated from trapped air in an ice core. Geophys. Res. Lett., 38, L21501, doi:10.1029/2011GL049444. [...] Zwally, H. J., and Coauthors, 2011: Greenland ice sheet mass balance: Distribution of increased mass loss with climate warming; 2003–07 versus 1992–2002. J. Glaciol., 57, 88–102.
Claim: Ice cores from Greenland show no significant warming, casting doubt on the climate change theory (Stephen Andrews, 2024-03-08)
Evidence (2018-04-24): The ca. 1100-year-long cold period is typically explained by an abrupt shift to a weaker state of the Atlantic Meridional Overturning Circulation (AMOC)19,20,21,22 in combination with atmosphere–sea-ice–ocean feedbacks8,9. The reason for the abrupt slowdown of the AMOC has been attributed to the excess freshwater fluxes into the North Atlantic Ocean in response to melting ice sheets9,21,22. Coupled atmosphere–ocean models, simulating a strong AMOC reduction during the YD11,21,23,24,25,26, generally reproduce the winter-dominated annual cooling signal in Greenland ice cores4,27 but fail to reproduce the European summer cooling11,28. It was hence suggested that forcings other than the AMOC slowdown and the associated cooling of the North Atlantic Ocean are required to explain the YD such as a reduction in solar activity28, a change in wind patterns29 or ice sheets30,31, or possibly a combination of an AMOC slowdown with lower solar activity11. As evidence for such a ~1100-long negative forcing is lacking, the mechanisms and/or regional climatic impacts of the YD remain elusive. [...] Steffensen, J. P. et al. High-resolution greenland ice core data show abrupt climate change happens in few years. Science321, 680–684 (2008). [...] Rasmussen, S. O. et al. A new Greenland ice core chronology for the last glacial termination. J. Geophys. Res. Atmos.111, D06102 (2006).
Claim: Ice cores from Greenland show no significant warming, casting doubt on the climate change theory (Stephen Andrews, 2024-03-08)
Evidence (2017-06-18): Euan Mearns, who runs a blog called Energy Matters, had a post in 2014 about The Vostok ice core: Temperature CO2 and CH4. This post has apparently had 8000 reads, is probably one of the most read texts on the subject, and yet, according to this post, the Climate Science community continues to ignore the fairly profound implications of what the data actually shows. [...] Eric Steig (who is one of the PIs of the WAIS Divide Ice Core) has highlighted a couple of other papers in this comment. In particular, Pedro et al. (2012), which says:
Claim: Ice cores from Greenland show no significant warming, casting doubt on the climate change theory (Stephen Andrews, 2024-03-08)
Evidence (2024-03-08): Ice cores pulled from ice sheets, such as that atop Greenland, offer some of the most telling insights for understanding past climate change. Each year snow falls atop the ice and compresses into a fresh layer of ice representing climate conditions at the time it formed. The abundance of certain forms, or isotopes, of oxygen and hydrogen in the ice allows scientists to calculate the temperature at which it formed, and air bubbles trapped within the ice reveal how much carbon dioxide and other greenhouse gases were in the atmosphere at that time. So drilling down into an ice sheet is like reading the pages of a history book that go back in time the deeper you go. [...] Together with other sources of information, such as sediment cores drilled from the seafloor and molecules preserved in ancient rocks, the ice cores allowed scientists to reconstruct past temperature changes in extraordinary detail. Many of those changes happened alarmingly fast. For instance, the climate in Greenland warmed abruptly more than 20 times in the last 80,000 years, with the changes occurring in a matter of decades. More recently, a cold spell that set in around 13,000 years ago suddenly came to an end around 11,500 years ago — and temperatures in Greenland rose 10 degrees Celsius in a decade.
Claim: Antarctic sea-ice extent is increasing to record levels. Antarctica is getting colder; its sea ice and ice cap are not melting (Judith Curry and Don Easterbrook, 2023-04-28)
Evidence (2023-04-28): Despite a period of slight growth between 1979 and 2014, Antarctic sea ice cover is not increasing to record levels. The trend reversed in 2014 and ice cover started to decrease vigorously. Many long-term measurements from Antarctic research stations show no significant warming or cooling trends over the whole continent, but parts of the continent are among the regions experiencing the fastest warming in the world, and the ice cap is losing mass.
Claim: Antarctic sea-ice extent is increasing to record levels. Antarctica is getting colder; its sea ice and ice cap are not melting (Judith Curry and Don Easterbrook, 2023-04-28)
Evidence (2023-09-11): Something strange is happening to the Antarctic’s sea ice. The areal expanse of floating ice fringing the continent is not only at a record low for this time of year — surpassing a record just set in 2022 — but ice extent has been hitting record lows throughout the year. [...] The amount of ocean around Antarctica covered in sea ice in 2023 (red) has stayed well below the average from 1981 to 2010 (black). Sea ice expanse hit a record low in late February — surpassing a record set just in 2022 (blue). The sea ice expanse for every year from 1981 to 2021 is shown in gray. Even as the Southern Hemisphere shifted into winter, Antarctic sea ice remained at record low levels. On June 27, the ice was dotted across about 11.7 million square kilometers of ocean. That’s about 2.6 million square kilometers below the 1981–2010 average, and about 1.2 million square kilometers below the previous lowest extent on record for June 27, set in 2022.
Claim: Antarctic sea-ice extent is increasing to record levels. Antarctica is getting colder; its sea ice and ice cap are not melting (Judith Curry and Don Easterbrook, 2023-04-28)
Evidence (2024-05-10): J. C. Comiso, A. C. Bliss, R. Gersten, C. L. Parkinson, and T. Markus Background The sea ice cover is one of the key components of the polar climate system. It has been a focus of attention in recent years, largely because of a strong decrease in the Arctic sea ice cover and modeling results that indicate that global warming is amplified in the Arctic on account of ice-albedo feedback. This results from the high reflectivity (albedo) of the sea ice compared to ice-free waters. A satellite-based data record starting in late 1978 shows that indeed rapid changes have been occurring in the Arctic, where the ice coverage has been declining at a substantial rate. In contrast, in the Antarctic the sea ice coverage has been increasing although at a lesser rate than the decreases in the Arctic. Shown below are up-to-date satellite observations of the sea ice covers of both the Arctic and the Antarctic, along with comparisons with the historical satellite record of more than 4 decades.
Claim: Antarctic sea-ice extent is increasing to record levels. Antarctica is getting colder; its sea ice and ice cap are not melting (Judith Curry and Don Easterbrook, 2023-04-28)
Evidence (2024-02-11): Sea-ice extent around the frozen continent was measured at 1.99 million square kilometres, with scientists suggesting a ‘regime shift’ could be underway. [...] On September 10, 2023, Antarctica’s maximum winter sea-ice extent dipped to a new record low of 16.96 million square kilometres. Above graph: Daily observations of overall Antarctic sea-ice extent [SIE] reveal 2023 (dark green line) as the lowest winter extent since records began in 1979. The light green line shows 2014 data, with the record high (winter) Antarctic SIE of 20.12 million square kilometres. The dark green line shows the 2023 data, with the current record low summer and winter Antarctic SIE. The black line shows the long-term mean SIE based on 1981–2010, with grey traces showing the remaining observations for each year since 1979. Credit A. Steketee and P. Heil using data from NSIDC (data from 11 February 2024).
Claim: Antarctic sea-ice extent is increasing to record levels. Antarctica is getting colder; its sea ice and ice cap are not melting (Judith Curry and Don Easterbrook, 2023-04-28)
Evidence (2024-04-16): Historically, the area of sea ice surrounding the Antarctic continent has fluctuated dramatically from year to year while averages over decades have been relatively stable. In recent years, though, sea ice cover around Antarctica has plummeted. "In 2016, we saw what some people are calling a regime shift," said sea ice scientist Walt Meier of the National Snow and Ice Data Center at the University of Colorado, Boulder. "The Antarctic sea ice coverage dropped and has largely remained lower than normal. Over the past seven years, we’ve had three record lows." This year, Antarctic sea ice reached its lowest annual extent on Feb. 20 with a total of 768,000 square miles (1.99 million square kilometers). That’s 30% below the 1981 to 2010 end-of-summer average. The difference in ice cover spans an area about the size of Texas. Sea ice extent is defined as the total area of the ocean in which the ice cover fraction is at least 15%.
Claim: Antarctic sea-ice extent is increasing to record levels. Antarctica is getting colder; its sea ice and ice cap are not melting (Judith Curry and Don Easterbrook, 2023-04-28)
Evidence (2024-02-29): Antarctic sea ice waxes and wanes with the seasons, and is at its annual minimum in late summer. [...] In February 2023, Antarctic sea ice extent broke the record minimum, set only a year earlier in February 2022. At the time of writing, sea ice may not have yet reached its minimum for 2024, but it’s already the third-lowest sea ice summer on record. [...] Variability of Antarctic sea ice is high, making it challenging to place the current low sea ice conditions into context. The satellite observational record only began in November 1978, so it’s difficult to disentangle decadal variations in sea ice with long-term climate change.
Claim: Antarctic sea-ice extent is increasing to record levels. Antarctica is getting colder; its sea ice and ice cap are not melting (Judith Curry and Don Easterbrook, 2023-04-28)
Evidence (2023-07-25): Sea ice surrounding Antarctica reached a new record high extent this year, covering more of the southern oceans than it has since scientists began a long-term satellite record to map sea ice extent in the late 1970s. The upward trend in the Antarctic, however, is only about a third of the magnitude of the rapid loss of sea ice in the Arctic Ocean. The new Antarctic sea ice record reflects the diversity and complexity of Earth’s environments, said NASA researchers. Claire Parkinson, a senior scientist at NASA’s Goddard Space Flight Center, has referred to changes in sea ice coverage as a microcosm of global climate change. Just as the temperatures in some regions of the planet are colder than average, even in our warming world, Antarctic sea ice has been increasing and bucking the overall trend of ice loss. [...] Since the late 1970s, the Arctic has lost an average of 20,800 square miles (53,900 square kilometers) of ice a year; the Antarctic has gained an average of 7,300 square miles (18,900 sq km). On Sept. 19 this year, for the first time ever since 1979, Antarctic sea ice extent exceeded 7.72 million square miles (20 million square kilometers), according to the National Snow and Ice Data Center. The ice extent stayed above this benchmark extent for several days. The average maximum extent between 1981 and 2010 was 7.23 million square miles (18.72 million square kilometers).
Claim: Antarctic sea-ice extent is increasing to record levels. Antarctica is getting colder; its sea ice and ice cap are not melting (Judith Curry and Don Easterbrook, 2023-04-28)
Evidence (2024-01-01): Antarctic sea ice extent appears to have broken the record low set last year. With a couple more weeks likely left in the melt season, the extent is expected to drop further before reaching its annual minimum. Much of the Antarctic coast is ice free, exposing the ice shelves that fringe the ice sheet to wave action and warmer conditions. On February 13, 2023, Antarctic sea ice extent fell to 1.91 million square kilometers (737,000 square miles) (Figure 1a). This set a new record low, dropping below the previous record of 1.92 million square kilometers (741,000 square miles) set on February 25, 2022 (Figure 1b). This year represents only the second year that Antarctic extent has fallen below 2 million square kilometers (772,000 square miles). In past years, the annual minimum has occurred between February 18 and March 3, so further decline is expected. [...] Antarctic sea ice extent has been highly variable over the last several years. While 2022 and 2023 have had record low minimum extent, four out of the five highest minimums have occurred since 2008. Overall, the trend in Antarctic minimum extent over 1979 to 2023 is near zero. The current downward linear trend in the Antarctic minimum extent from 1979 to 2023 is 2,400 square kilometers (930 square miles) per year, or 0.9 percent per decade, which is currently not statistically significant. Nevertheless, the sharp decline in sea ice extent since 2016 has fueled research on potential causes and whether sea ice loss in the Southern Hemisphere is developing a significant downward trend.
Claim: Antarctic sea-ice extent is increasing to record levels. Antarctica is getting colder; its sea ice and ice cap are not melting (Judith Curry and Don Easterbrook, 2023-04-28)
Evidence (2024-01-01): Daily Sea Ice Extent Time Series The monthly Sea Ice Index provides a quick look at Antarctic-wide changes in sea ice. It is a source for consistently processed ice extent and concentration images and data values since 1979. Monthly images show sea ice extent with an outline of the 30-year (1981-2010) median extent for that month (magenta line). Other monthly images show sea ice concentration and anomalies and trends in concentration. The daily Sea Ice Index provides a quick look at Antarctic-wide changes in sea ice. It provides consistently processed daily ice extent and concentration images and data since 1979. Daily extent images show ice extent at concentrations greater than 15% for a given day with an outline of the typical extent for that day based on a 30-year (1981-2010) median (orange line).