copenlu/druid huggingface dataset:
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 (2022-03-10): A new record minimum for Antarctic sea ice [...] Antarctic sea ice extent reached a new record low of 1.965 million km2 on 23 February 2022. This extent is approximately 32% below climatological values and might indicate a transition to new, more extreme, annual fluctuations. [...] Handcock, M. S. & Raphael, M. N. Modeling the annual cycle of daily Antarctic sea ice extent. The Cryosphere14, 2159–2172 (2020).
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 (2023-09-25): On September 10, 2023, sea ice in the Antarctic reached an annual maximum extent of 16.96 million square kilometers (6.55 million square miles), setting a record low maximum in the satellite record that began in 1979. This year’s maximum is 1.03 million square kilometers (398,000 square miles) below the previous record low set in 1986. It is also 1.75 million square kilometers below (676,000 square miles) below the 1981 to 2010 average Antarctic maximum extent. Sea ice extent is markedly below average north of Queen Maud Land and west of the Antarctic Peninsula. Other low areas include the Indian Ocean and Ross Sea. Extent is above average stretching out of the Amundsen Sea. [...] This year marks a significant record low maximum in Antarctic sea ice extent (Figure 2). Since early April 2023, sea ice maintained record low ice growth. From early to mid-August, growth slowed considerably, maintaining a difference of nearly 1.5 million square kilometers (579,000 square miles) between 2023 and 1986, the second lowest year on satellite record. After that period, ice growth quickened and narrowed the gap to about 1 million square kilometers (386,000 square miles). This is the first time that sea ice extent has not surpassed 17 million square kilometers (6.56 million square miles), falling more than one million square kilometers below the previous record low maximum extent set in 1986.
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 (2024-05-22): Winter 2023's Antarctic sea ice was at its lowest level since satellite measurements began. A new study shows how unlikely this would be without man-made factors. For decades, scientists have gathered evidence that climate change is melting sea ice in the Arctic. But Antarctica has been this weird outlier. The region's sea ice melt hasn't been so dramatic. That's because the two places are quite literally polar opposites. The Arctic up north is an ocean surrounded by land. The Antarctic in the South is land surrounded by ocean. [...] FADEL: Antarctic sea ice plummeted to the lowest point on record, but it wasn't immediately clear whether human activity caused that. There's a lot going on in the Antarctic climate, Holmes says.
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 (2023-09-13): Antarctic sea ice is a critical component of the global climate system1,2,3. Climatologically, Antarctic sea ice reaches its annual minimum in mid-February to early March. Sea ice coverage in January and February 2023 broke monthly and daily sea ice extent records for this time of year4. On 10 February 2023, sea ice coverage broke the record daily minimum of 1.91 million square kilometres set one year earlier on 21 February 20224,5. On 19 February 2023, a new minimum Antarctic sea ice extent of 1.77 million square kilometres was observed4, 1.02 million square kilometres (36%) less than the 1979-2022 average daily minimum sea ice coverage. [...] The multi-decade increase in Antarctic sea ice that peaked in 2014, identified here as a high sea ice state between mid-2007 and mid-2016, has been examined extensively, with contributions from high-latitude winds12,13 and Antarctic meltwater14,15 suggested to have played a role. Positive ocean-sea ice feedbacks may have perpetuated the high sea ice coverage16 during this period. In spring 2016, Antarctic sea ice rapidly transitioned to a new, low sea ice state.
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 (2024-10-03): Antarctic sea ice has likely reached its maximum extent for the year, at 17.16 million square kilometers (6.63 million square miles) on September 19, according to scientists at the National Snow and Ice Data Center (NSIDC) at the University of Colorado Boulder (CU Boulder). The 2024 maximum is the second lowest in the 46-year satellite record. The record low maximum occurred in 2023. "The dramatic downward step in southern winter sea ice spanning the past two years points more than ever to effects from a record-warm ocean on Antarctic climate," said senior research scientist Ted Scambos of the Cooperative Institute for Research in Environmental Sciences (CIRES) at CU Boulder. NSIDC scientists stress that the Antarctic sea ice extent number is preliminary—weather conditions could still push the ice extent higher. NSIDC will issue a full analysis in October addressing the possible causes behind this year’s ice conditions, interesting aspects of the growth season, the setup going into the austral summer melt season, and graphics comparing this year to the long-term record. There is also some uncertainty in the estimate and date because of an outage in the input source data from September 12 to 18. However, that does not affect the ranking or the long-term trends.
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 (2023-09-16): The sea-ice surrounding Antarctica is well below any previous recorded winter level, satellite data shows, a worrying new benchmark for a region that once seemed resistant to global warming. [...] Sea-ice forms in the continent's winter (March to October) before largely melting in summer, and is part of an interconnected system that also consists of icebergs, land ice and huge ice shelves - floating extensions of land ice jutting out from the coast. [...] Sea-ice has broken record minimums in summer for three of the past seven years, including February 2023.
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 (2023-10-27): On September 10th, Antarctica's sea ice reached its largest extent of the year, but it was far smaller than average sea ice in decades past. In fact, it was nearly 350,000 square miles smaller than the previous record smallest amount, measured in 1986, according to a recent analysis by the National Snow and Ice Data Center, a research center at the University of Colorado, Boulder that is also affiliated with the federal government. Disappearing sea ice is a problem for lots of reasons. While it doesn't directly add any extra water to the ocean, missing sea ice does contribute to global sea level rise in other ways. The sea ice around Antarctica shields glaciers on land, and massive ice shelves that extend out into the water, from storms and above-freezing ocean water. Without that protection, that ice can melt more quickly, and that leads to more sea level rise. [...] "There is growing evidence that the Antarctic sea ice system has entered a new regime, featuring a much stronger influence of warm ocean waters limiting ice growth," scientists at the National Snow and Ice Data Center write in their analysis of this year's record-shattering low sea ice extent.
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. Cherry-picking Antarctic sea-ice extent reached a record high in 2014, but that was not the sign of a long term trend of expansion since a precipitous decline followed, with the sea ice extent reaching its lowest value in 40 years. [...] Former climatologist Judith Curry, who called into question the fact that humans are the dominant cause of recent climate change in Congressional Testimony, first claims that "Antarctica sea ice extent is increasing to record levels". Sea ice extent refers to the cumulative area of all ocean surfaces where water is covered with ice. On the other hand, the terms ice cap and ice sheet refer to ice covering terrain such as land or bedrock. In order to understand the trends in sea ice extent, scientists study its area in February and September, respectively the periods in which the ice cover retreats and peaks.
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 (2016-09-16): Since 1979, the total annual Antarctic sea ice extent has increased about 1 percent per decade. Compared to the Arctic, the signal has been a "noisy" one, with wide year–to-year fluctuations. For three consecutive Septembers (2012 to 2014), satellites observed new record highs for winter sea ice extent around Antarctica. The largest of those occurred in September 2014, when the ice reached 20.14 million square kilometers (7.78 million square miles). Still, increases in Antarctic sea ice are exceeded by decreases in the Arctic. That is to say, global sea ice is decreasing even as Antarctic sea ice is increasing slightly. [...] Antarctic sea ice trends are smaller and more complex. Relative to the average from 1981 to 2010, the Antarctic sea ice extent increased about 1 percent per decade, but the trends were not consistent for all areas or all seasons. The variability in Antarctic sea ice patterns makes it harder for scientists to explain Antarctic sea ice trends and to predict how Southern Hemisphere sea ice may change as greenhouse gases continue to warm the Earth. Climate models do predict that Antarctic sea ice will respond more slowly than Arctic sea ice to warming, but as temperatures continue to rise, a long-term decline is expected.
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 (2020-11-30): Antarctic sea ice has grown somewhat over the past 10 years. Between 2012 to 2014, it reached record-high extents each year during the winter. It topped 7.78 million square miles in September 2014, the largest extent since satellites started keeping accurate measurements in 1979. [...] The Antarctic freezing trend has not been captured well by climate models. So scientists have been trying to understand why planetary warming has not melted Antarctic sea ice like it has in the Arctic. In the new study, Son Nghiem, a researcher with NASA’s Jet Propulsion Laboratory, evaluated satellite data to zero in on an answer. [...] As the Antarctic sea ice reached record levels, scientists floated several hypotheses, including possible changes in the ozone hole over Antarctica, or increased amounts of fresh water—which freezes more easily—on the surface of the ocean around Antarctica. At the same time, they said it’s important to remember the big differences between the poles. Assessing sea ice dynamics at opposite ends of the Earth is not an apples-to-apples proposition.
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 (2023-09-26): Sea ice around Antarctica reached its lowest winter maximum extent on Sept. 10, 2023, at 6.5 million square miles (16.96 million square kilometers). That’s 398,000 square miles (1.03 million square kilometers) below the previous record-low reached in 1986 – a difference that equates to roughly the size of Texas and California combined. The average maximum extent between 1981 and 2010 was 7.22 million square miles (18.71 million square kilometers). "It’s a record-smashing sea ice low in the Antarctic," said Walt Meier, a sea ice scientist at NSIDC. "Sea ice growth appears low around nearly the whole continent as opposed to any one region." [...] This record-low extent so far in 2023 is a continuation of a downward trend in Antarctic sea ice that started after a record high in 2014. Prior to 2014, ice surrounding the continent was increasing slightly by about 1% per 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 (2023-11-07): UNIVERSITY PARK, Pa. — As the world continues to warm, Antarctica is losing ice at an increasing pace, but the loss of sea ice may lead to more snowfall over the ice sheets, partially offsetting contributions to sea level rise, according to Penn State scientists. [...] The findings, researchers said, suggest that as global temperatures inch upwards and Antarctica warms, shrinking sea ice levels will amplify oceanic evaporation and consequent precipitation over Antarctica. This increased snowfall can momentarily stave off rising sea levels. However, sea levels will still rise overall. [...] "While Arctic sea ice has been rapidly declining over the satellite record, the Antarctic experienced a slight increase until 2015, followed by a sharp decline in 2016," Kromer said. "In 2022, we witnessed a new record low, and this year's levels are even lower, significantly below previous observations. These recent rapid changes in Antarctic sea ice highlight the urgency of understanding their causes and their potential impact on the Antarctic ice sheet."
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 (2021-07-13): - Be aware that the ice in the water will melt faster than the ice on the "land." [...] Icebergs and frozen seawater also melt in warm temperatures but are not significant contributors to sea level rise. This is because they are already in the water. The volume of water they displace as ice is about the same as the volume of water they add to the ocean when they melt. As a result, sea level does not rise when sea ice melts. While density differences between salt water and freshwater result in a difference between the volume of salty sea water being displaced by sea ice and the freshwater that would result from the melting of that sea ice, it is minimal and beyond the scope of this lesson. Another contributor to sea-level rise is the increase in volume that occurs when water is heated, called thermal expansion. Both thermal expansion and ice melt are the results of the rise in global average temperatures on land and sea known as 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 (2022-02-11): Sea ice covers the ocean surrounding Antarctica, forming a key component of the coupled ocean-atmosphere-cryosphere system in southern high latitudes that helps regulate climate, ocean circulation, and marine ecosystems. The extent of Antarctic sea ice varies greatly from year to year, but 40 years of satellite records show a long-term trend. Although some Antarctic regions have experienced reductions in sea ice extent, the overall trend since 1979 shows increased ice. The increase in Antarctic sea ice extent stands in stark contrast to conditions in the Arctic, where sea ice extent has declined significantly—by about 2 million square kilometers, or about 20%, over the past 40 years. Much of the observed loss of Arctic sea ice, which is in general agreement with expectations from climate models, has been attributed to anthropogenic global warming. [...] Antarctic sea ice is bordered by the ice-free Southern Ocean, which itself has experienced cooling SSTs over recent decades. This cooling trend is partly due to natural variability and partly due to upwelling currents that bring to the surface deep waters that have not yet warmed because of anthropogenic climate change [e.g., Armour et al., 2016].
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 (2023-05-11): Glaciers and ice sheets, large land-based formations of ice, are melting as global temperatures rise. That meltwater drains into the sea, increasing the ocean's water volume and global sea level. Melting ice has caused about two-thirds of the rise in sea level to date, one-third from land ice in Greenland and Antarctica and one third from melting ice on mountains. Ice sheets and glaciers in Greenland and Antarctica melt three ways: from above due to warming air, from the sides as they break off into the sea, and from below due to warming ocean water where the ice extends over the sea. Because of this, the rate of ice melt varies from place to place as conditions change. The Arctic is warming more quickly than the Antarctic, which explains why the ice there is thinning more quickly. However, recent research suggests that the melting of Antarctica’s ice shelves may be unstoppable—although the process may take centuries.
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 (2024-01-31): Between 1979 and 2015, average Antarctic sea ice extent – the area of ocean with at least 15% sea ice cover – increased slightly, but fairly steadily. This is in stark contrast to the Arctic, where sea ice at the minimum summer extent plummeted by nearly 12% per decade. Then, after a record high year in 2014, Antarctic sea ice extent dropped to a record low in 2017. Several years of low sea ice came after that, with the summer minimum record smashed in 2022, when it fell below 2m square kilometres for the first time. [...] Antarctic daily sea ice extent from the US National Snow and Ice Data Center. The bold lines show daily 2023 values, the shaded area indicates the two standard deviation range in historical values between 1979 and 2010. The dotted line shows the record low. Chart by Carbon Brief.As the chart shows, 2023 was an exceptional year in the satellite record, remaining well below average for the entire year.
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): One major concern is that of declining sea ice in the Arctic and Antarctic. During the winter months in each hemisphere, the polar regions gain sea ice as seawater freezes. That total amount has been shrinking steadily in recent decades. Sea ice is critical habitat for a variety of animals, including polar bears, seals, and penguins. In addition to having effects on wildlife, declining sea ice accelerates the rate of ocean warming. Sea ice reflects sunlight, providing a buffer to the effects of warmer temperatures. When sea ice is lost and the darker ocean surface is exposed, more warmth is absorbed by the sea, exacerbating the effects of climate change. This is known as the ice-albedo feedback. [...] - Scripps Scientists Return from Year-Long Polar Drift Experiment - Satellite Record Gives Unprecedented View of Antarctic Ice Sheet Melt Pattern Over 25 Years - First Results From NASA’s IceSAT-2 Mission Map 16 Years of Melting Ice Sheets - Listen Up: Scripps Scientists Use Underwater Microphones to Study Calving Arctic Glacier - New Research is the First to Relate Antarctic Sea Ice Melt to Weather Change in the Tropics - Researchers Find New Reason Why Arctic is Warming So Fast - Tethered for Months to Floating Sea Ice, Scripps Researchers Join Largest Ever International Arctic Expedition
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 (2023-03-13): Usually, glaciers move at a glacial pace. The speedy collapse of the Conger's ice shelf came after some of the most dramatically warm weather ever observed in Antarctica. For the first time since satellite monitoring began in 1979, the sea ice extent around Antarctica dropped below 2 million sq km (770,000 sq miles). Less sea ice means more waves battering the ice shelves in front of the glaciers. Massive fields of sea ice off of Adelie Land, Wilkes Land and Princess Elizabeth Land in East Antarctica completely disappeared. The lack of ice startled scientists. Unlike in the Arctic, Antarctic sea ice had been slightly increasing over the period that satellites had been able to monitor it, and some suggested that circumpolar winds and ocean currents were isolating it from global warming. A study later blamed the 2022 sea ice low on ocean heating, as well as intense winds driven by La Niña and other weather patterns. [...] "If you're going to apply a really sophisticated model over a topography that's just flat because you've got no data, it's pointless," Siegert says. Antarctica's ice is melting not from above but from below. As relatively warm ocean water eats away at the sloping underside of an ice shelf, the grounding line where it meets the seafloor recedes. That process should stop at the coast – unless the bottom of the glacier there is below sea level. The Icecap planes' ice-penetrating radars helped discover a "weak underbelly" below East Antarctica's largest glacier Totten, which holds about as much potential sea level rise as all of West Antarctica.
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 (2024-10-03): Charctic Interactive Sea Ice Graphing Tool [...] Sea ice extent spatial comparison tool [...] Since 2007, this site has been a go-to source for blog-like insights, analysis, and data visualization tools that communicate how sea ice has been changing from year to year. We receive over two million page visits a year and our content is used by a wide range of users including journalists, the general public, academics, and scientists alike. Our analyses focus primarily on sea ice extent, which is a measurement of the area of ocean where there is at least some sea ice. In the Arctic, the annual minimum sea ice extent occurs in September and the annual sea ice maximum extent occurs in March. In the Antarctic, the minimum extent occurs in February and the maximum occurs in September. When compared with previous years and decadal averages, these periods when the annal extremes occur are particularly important indicators of how much ice is being lost over time.