Sea ice melt in the Arctic Basin leaves an area for polar bears larger than Greenland

Reposted from Dr. Susan Crockford’s Polar Bear Science

Posted on August 29, 2019

Sea ice melt in the Arctic Basin leaves an area for polar bears larger than Greenland

Most polar bears that spend the spring feeding in the peripheral seas of the Arctic Basin (such as the Beaufort, Chukchi, Kara, and Barents Seas) remain on the persistent pack ice of the central Arctic during the summer and this August, that refugium is still larger than Greenland. Most of these bears do not use this July-September Arctic Basin ice as a hunting platform unless they are very lucky: the few seals available are hard to catch. For the most part, polar bears fast or eat very little during the summer whether they are on land or on ice (see references in this post).

svalbard-polar-bear-fall-2015_aars

Since early June, sea ice experts have been wringing their hands over the melting of Arctic sea ice and offering breathless speculation that this year’s September minimum could be – gasp! – as low as or less than 2012 or even less. But now, as the graph of ice cover at 28 August shows below, that outcome is looking not just unlikely but virtually impossible (the blue line is 2019 extent, red dashed line is 2012, and the brown line is 2016):

Sea ice extent 2012 and 2016 vs 2019 with 2x deviation at 28 Aug_NSIDC interactive

As expected, the failure of the ice to remain on track to set a new record September low due to global warming is shrugged off with a reminder that summer ice extent “is sensitive to changes in daily weather conditions.”

Arctic Basin

According to NSIDC Masie ice charts shown below, there is exactly the same amount of ice in the Arctic Basin this year at the end of August – 3.0 mkm2 – as there was in 2012: it was just distributed a little differently. This makes the usual summer refugium for many polar bears larger in area than all of Greenland, which is only about 2.17 mkm2. That’s plenty of space for thousands of bears to hang out for a few months.

Sea ice in the Arctic Basin at 26 August 2019 (3.0 mkm2):

masie_all_r11_v01_2019238_4km

Sea ice in the Arctic Basin at 26 August 2012 (3.0 mkm2):

masie_all_r11_v01_2012239_4km

At 26 August 2019, sea ice was still present in the peripheral seas: packed into the Canadian Arctic Archipelago, off northeast Greenland and the northern Barents Sea as well as the northern Laptev Sea. This is lots of ice for summering polar bears:

masie_all_zoom_4km 2019 Aug 26

Barents Sea and Svalbard

In 2012, the Barents Sea was totally ice-free by late July yet when the Svalbard polar bear population survey was completed in August 2015, the population had grown by 42% – this was apparently a non-statistically significant increase but definitely not a decline. Ongoing research shows Svalbard bears are still thriving.

The low sea ice coverage in the western Arctic since early summer this year has been more than balanced out by the abundance of ice in the eastern Arctic: ice loss in the Beaufort and Chukchi Seas early in the season was the Barents Sea’s gain.

Barents Sea ice 2019 Aug 26_NIS

Barents Sea polar bears now have ice close to shore this summer but it remains to be seen if this will garner any advantage to their health and survival compared to previous years.

FullSize_CICE_combine_thick_SM_EN_20180801

Last year at the beginning of August (above), there was no ice anywhere near Svalbard but this year just days from the end of August (below) the northeast portion of Svalbard is surrounded by ice that’s 2 metres thick! However, polar bears don’t need thick ice: half a metre of ice (i.e. 50 cm) is more than enough to support a full grown bear. We know this because in the fall, bears on land head out on ice when it’s about 30 cm thick.

sea ice thickness 26 Aug 2019 note Svalbard

Svalbard ice extent this year is much higher than average:

Svalbard ice extent 2019 Aug 26 graph_NIS

Sea ice at Svalbard, 26 August 2019:

Svalbard ice extent 2019 Aug 26_NIS archive

Compare above to 27 August 2012 (below):

Svalbard ice extent 2012 Aug 27_NIS archive

Polar bear specialist Andrew Derocher claims that lots of ice this year around Svalbard is good news for polar bears but the evidence from previous years shows that no ice around Svalbard at the height of summer has not been detrimental to their health and survival (Aars 2018; Aars et al. 2017; Andersen et al. 2012; Crockford 2019a, b).

Canadian Arctic Archipelago

Sea ice Canada 2019 Aug 27

Even more than a week earlier in 2012 (below, the only image I have is 19 Aug) the ice was mostly clear through the eastern approach to the northern route of the Northwest Passage. By the end of August, one small boat had made it through that tricky northern passage, which looks highly unlikely to be possible this year for vessels other than icebreakers.

Sea ice Canada_Aug 19 2012

Here is a satellite image of the route published by NASA on 2 August 2012, but note this caveat:

“According to reports from the Canadian Ice Service, ice appeared to retreat quickly from Parry Channel in late July and early August 2012, but the channel was probably not entirely open. In some cases, sea ice can be thin enough to escape detection by a satellite sensor, but still be thick enough to hamper navigation.”

Northwest Passage_NASA_labeled_tmo_2012_Aug 2

Northwest Passage routes:

Northwest_passage_wikipedia

The fact that the Royal Canadian Mounted Police schooner St. Roch was able to transit the northern passage in the summer of 1944 from east to west, encountering little ice for much of the middle portion of the journey, is evidence that ice-free conditions in Parry Channel occurred naturally even before global warming. A detailed account of the St. Roch voyages (a fascinating read with a map and lots of pictures, from Canadian Geographic 1945) is available here in pdf format.

References

Aars, J. 2018. Population changes in polar bears: protected, but quickly losing habitat. Fram Forum Newsletter 2018. Fram Centre, Tromso. Download pdf here (32 mb).

Aars, J., Marques,T.A, Lone, K., Anderson, M., Wiig, Ø., Fløystad, I.M.B., Hagen, S.B. and Buckland, S.T. 2017. The number and distribution of polar bears in the western Barents Sea. Polar Research 36:1. 1374125. doi:10.1080/17518369.2017.1374125

Andersen, M., Derocher, A.E., Wiig, Ø. and Aars, J. 2012. Polar bear (Ursus maritimus) maternity den distribution in Svalbard, Norway. Polar Biology 35:499-508.

Crockford, S.J. 2019a. State of the Polar Bear Report 2018. Global Warming Policy Foundation Report 32, London. pdf here.

Crockford, S.J. 2019b. The Polar Bear Catastrophe That Never Happened. Global Warming Policy Foundation, London. Available in paperback and ebook formats.

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52 thoughts on “Sea ice melt in the Arctic Basin leaves an area for polar bears larger than Greenland

  1. If all this weather is normal and just a part of the earths (suns influence?) natural system, then what is the end goal of stopping all fossil fuels? Rain, sun, winds, snow are things that have happened and will happen constantly, but now it seems that if it rains for more the 2m 34secs, its “climate change…. humans have only got stronger through all types of weather.

    • The end goal?

      “This is the first time in the history of mankind that we are setting ourselves the task of intentionally, within a defined period of time to change the economic development model that has been reigning for at least 150 years, since the industrial revolution. That will not happen overnight and it will not happen at a single conference on climate change, be it COP 15, 21, 40 – you choose the number. It just does not occur like that. It is a process, because of the depth of the transformation.”

      Christiana Figueres, Executive Secretary of the United Nations Framework Convention on Climate Change

      Or put more succinctly by George Orwell in his book 1984:

      “Power is not a means; it is an end. One does not establish a dictatorship in order to safeguard a revolution; one makes the revolution in order to establish the dictatorship. The object of persecution is persecution. The object of torture is torture. The object of power is power. Now do you begin to understand me?”

      • Power to push things just as we want them
        Control of people gives us such a huge rush
        Wealthy enough to buy those that we need
        These are a few of our favourite things

    • what is the end goal of stopping all fossil fuels?

      Impoverishment of the population
      Enrichment of the elite.

      Greens work for the people they warned you about.

    • The sea ice important to polar bears is land-fast shore ice in the spring, not floes in the summer.

      Ringed seal moms build lairs in the snow on land-fast ice and maintain holes to access the shallow water beneath. In these dens they give birth to pups, on which hungry bear moms snack after emerging from their winter quarters with growing cubs.

    • It’s that summer beach body/bikini body they are trying to get. Once winter sets in, the hormones change and they want to eat everything in sight…. just like people.
      Come cooler weather the Coca-Cola PBears just want snuggle up to the TV, watch sports, and drink and eat crappy comfort snack foods… like wandering baby harp seals.

    • Excerpted from article:

      Polar bear specialist Andrew Derocher claims that lots of ice this year around Svalbard is good news for polar bears but the evidence from previous years shows that no ice around Svalbard at the height of summer has not been detrimental to their health and survival

      I really don’t think Polar bears “give-a-growl” as to how much sea ice or pack ice there is during the “height of summer” ….. or anytime during the summer months.

      “DUH”, I’m sure the Polar bears are just lounging around, biding their time, waiting for the “pupping” to begin, to wit:

      Female harp seals give birth to pups between late February and mid-March.

      ……. the fertilized embryo doesn’t actually implant in the uterus for about three months. This ……..– allows the resulting birth to coincide with the seasonal buildup of the pack ice essential for pupping.
      Read more @ https://sciencing.com/life-cycle-harp-seals-6735960.html

      Just like the Brown bears know when the Salmon “runs” begin, ….. the Polar bears know when the seal “pupping” (birthing) begins.

  2. On the very day last month in which NASA breathlessly predicted the second lowest Arctic sea ice minimum for this year, the melt rate slowed. Uncanny!

    What the desperately hopeful “scientists” failed to realize is that most years since 2007 have rougghly tracked 2012 during early August, so there was no reason to think that in 2019, as in most previous years, the melt rate would slow in the second half of the month and September. In the low years of 2007, 2016 and 2012, late season cyclones broke and piled up the floes, reducing the area with ice cover.

    Even should 2019 end up the second lowest, its minimu area is likely to be much higher than NASA’s low, low, wishful-thinking forecast, so close to 2012. Will be fun to see how they spin their big mistake in their report on the second half of August.

    https://nsidc.org/arcticseaicenews/

    “Is a new record minimum possible?”

    “The ASINA team conducted a revised analysis of the likely course of the 2019 Arctic summer sea ice minimum, using rates of loss from several recent years. While sea ice extent is now above extent for the same date in 2012, overall our projection for the minimum is lower than estimated in our previous post. Using the average decline rate of the past 12 years, from 2007 to 2018, the 2019 minimum is estimated to be 3.75 million square kilometers (1.45 million square miles). If the 2012 decline pattern is applied from August 14 forward, sea ice reaches 3.44 million square kilometers (1.33 million square miles). This is still above the 2012 summer minimum extent of 3.39 million square kilometers (1.31 million square miles). However, nearly all of the recent rates of sea ice loss lead to 2019 being second lowest in ice extent, surpassing 2007 and 2016.”

    At the moment, Arctic sea ice looks on track to finish fourth, fifth or sixth lowest, ie above 2012, 2016 and 2007, challenging 2011 and 2015. But I don’t want to commit the NASA’s extrapolation error. Weather could still take the ice higher or lower than this guess before the September minimum.

  3. Oh but I thought arctic sea ice was in a fee fall this year, just ask captain BS Griff. I have been listen to the same garbage since god knows when, at least 2007. The Arctic is not melting any faster if anything it has pasted the bottom and has begone a slow growth phase.

    • Since its storm-driven low in 2012, Arctic sea ice minimum extent has been gaining. The five-year average for 2013-17 was higher than for 2007-11. Then last year was almost as high as 2017. This year will probably be a little lower than 2018.

      The three lowest years, 2007, 2012 and 2016, all suffered Arctic cyclones, to include two in the latter.

      So the trend is flat since 2007 and up since 2012.

      Starting from the near century high in 1979-88, each subsequent decadal average was lower, but that trend may well reverse in 2019-28, from the low in 2009-18.

      As with so much else in climate, Arctic sea ice is cyclical.

    • Arctic sea ice minima:

      2012: 3387 (Cyclone)
      2007: 4155 (Cyclone)
      2016: 4165 (Two cyclones, super El Nino)
      2011: 4344
      2015: 4433

      2008: 4590
      2010: 4615
      2018: 4656
      2017: 4665
      2014: 5029

      2013: 5054
      2009: 5119

  4. I notice that the “Sea Ice Extent” graphs on the WUWT Sea Ice Reference Page are 2 weeks stale. Also got NOT FOUND when clicked on “JAXA data download” link.

    • Yeah, in lieu of that being fixed, I’ve been using this link:

      http://nsidc.org/arcticseaicenews/charctic-interactive-sea-ice-graph/

      It’s pretty good. I believe it’s Walt Meier’s handiwork, right? He’s always done a good job.

      I wonder if Griff would give us an explanation as to why, if he and his ilk want the Arctic to retain more sea ice in summer, they can’t hide their glee when it looks on track to be lower. Maybe Griff’s psychiatrist would be a better source.

  5. When I went to the Sea Ice Page, the several graphs showed the ice extent to be about equal with 2012. That mystifies me a bit because this winter wasn’t too warm. There was a WUWT story a while back that mentioned abnormally thick ice. IIRC the ice extent in 2012 was caused by winds that blew a lot of ice out of the arctic. It seems that the sea ice extent is a bit complicated. It also appears that the minimum ice extent has more or less plateaued.

    • As is often the case from mid-June to mid-August, ice extent was close to 2012 this year. But then it kept falling in late Aug, due to a cyclone. This year, not so much.

    • And it seems daily weather events play a more important role in their variance, wind, cloud cover, quality and frequency of light(wavelengths), air particle quality, etc.

  6. Thanks Susan. – – and ctm

    If that end to the melt holds, I think it is about 3 weeks early, maybe some smart person will give us an explanation. On the other hand, I don’t have a chart of the variation around that mean date. So, maybe this is dynamic Earth at its usual crazy self.

    For what it is worth, central Washington USA has been tracking on the slightly low side of normal for the last 2 months.
    It is summer, but the highs have been 90-ish, rather than in the low 100s. Charts here:
    https://www.wrh.noaa.gov/climate/temp_graphs.php?stn=KYKM&submit=Change+Station&wfo=pdt

    • Minimal Arctic sea ice extent can come in either half of September. I haven’t checked every year in the dedicated satellite record, but don’t think it has ever happened in August, and rarely in the first or last week of September. In the 30-year median, it’s September 17.

      The trend for Antarctic sea ice in the 40-year record remains up, with reord maximum in 2014.

  7. I still don’t understand why all the fuss about sea ice. I also don’t understand some “scientists” who think this is unprecedented in any way, apart from our incredibly myopic view that right now is somehow different.

  8. Great article Dr. Crockford, but did you mean this to come out like it did:

    “The fact that the Royal Canadian Mounted Police schooner St. Roch was able to transit the northern passage in the summer of 1944 from east to west, encountering little ice for much of the middle portion of the journey, is evidence that ice-free conditions in Parry Channel occurred naturally even before global warming.” ??

    The globe has warmed since exiting the Little Ice Age, ca. 1850. I think you may have fallen into the trap of using the alarmist parrot meme.

    • Hard facts & truth about cute Polar Bears; plus cosy slumber on good ol’ “global warming tales” pillow.

      Dichotomy of a sorrowful caring soul.

  9. Three million km2 that’s like the entire contiguous US or two Alaskas. Giving each bear 100 km2. 9r about 2 bears roaming Long Island NY. How do they even find each other? How do they reproduce? Maybe we should sponsor a dating site for them. Or we can get volunteers to drive them on dates. AOC would definitely be interested in spending money on that. /sarc

    • Polar bears have a mind-boggling olfactory sense.

      They can smell ringed seals under snow from a mile away. A sow in heat would attract boars from far and wide.

  10. From Crockford’s “10 fallacies about Arctic sea ice and polar bear survival”:

    “2. Polar bears need summer sea ice to survive. False: polar bears that have fed adequately on young seals in the early spring can live off their fat for five months or more until the fall, whether they spend the summer on land or the Arctic pack ice. Polar bears seldom catch seals in the summer because only predator-savvy adult seals are available and holes in the pack ice allow the seals many opportunities to escape ”

    They may be able to live off their fat until fall, but if warming means the ice disappears earlier and reforms later, that gives the bears less time to renew depleted fat stores for the winter.

    One of the main hunting techniques of bears is to wait at seal breathing holes, and catch them as they surface. So holes in the ice are necessary for this method of hunting, which can continue into July if conditions are right. Of course, breathing holes are only necessary in ice that is continuous; when the ice is broken up, the bears can no longer predict where the seals will surface.

    (Her point 10 seems just odd. Scientists say that there are 19 subpopulations that will respond differently according to the environment. Dr. Crockford says this is wrong because the scientist got their predictions of changing sea ice in different regions wrong, but that doesn’t seem to falsify the initial premise. Hard to assess, since her citation is a twitter feed.)
    ………………………………………..
    Another factor is the successful breeding of seals, which can also be weather ( and climate) dependent.

    The fact that polar bear numbers in some areas has increased is not surprising, since hunting once decreased their numbers below carrying capacity (the number of bears an environment is capable of supporting). It seems odd that Dr. Crockford doesn’t differentiate population rebound due to lower hunting pressure from general population well-being due to adequate diet – but maybe she does elsewhere.

    I don’t think it’s a major concern of scientists how many bears there are total now so much as the fact that at least one population is decreasing, and this is apparently due to warming. It’s the future that is the real concern – what would happen if the Arctic experiences multiple years in a row of very low sea ice? While there are terrestrial prey, it is not likely that they provide the necessary calories to sustain polar bear populations. It is not just the survival of individual bears, it’s how able they are to produce surviving offspring. Polar bears have a low reproduction rate, so this is important.

    Seal breeding is also dependent on weather conditions. They may be fat and healthy, and still unable to produce and raise offspring if there is too much or too little snow, or too much rain.

    (Killer whales have begun hunting in the Arctic, something that didn’t happen often in the past. It is clear that the ecosystem is changing.)

    “But now, as the graph of ice cover at 28 August shows below, that outcome is looking not just unlikely but virtually impossible”

    I don’t understand this comment at all. How can Dr. Crockford forecast the weather so well that she can be that confident? Regardless, it’s not a matter of record-setting, it’s a matter of the long-term trend, and that has been toward declining sea ice extent.

    To be clear, I have not read Dr. Crockford’s book. I have no emotional investment in polar bears, but as top predators they are keystone species in the Arctic environment, and their populations are important. I am certainly no expert on their biology or ecology. However, I don’t see any reason to consider her more of an expert on polar bear population status and future threat than the many others who study them and have produced more original peer-reviewed research on them, especially when I find her arguments unconvincing. To me, expressing a minority opinion is not automatically a sign of greater understanding. But that’s just me.

    • Kristi R Silber,

      For decades alarmists have been claiming reducing Arctic ice cover threatens survival of polar bears. Meanwhile, in reality polar bear numbers have been increasing.

      In other words, reality is observed to have been – and to still be – the opposite of the alarmists’ claims.

      One scientist, Susan Crockford, whose work consists of studying polar bears has persistently explained why reality has been the opposite of the alarmists’ claims. She has published a book in which she spells out her research and how that research indicates the alarmists’ claims are not likely to ever become true.

      You say you have not read her book but say you “don’t see any reason to consider her more of an expert on polar bear population status and future threat than the many others” (all of whom continue to be shown to be wrong by observations of reality).

      I think only a fool would assert the alarmists have as much credibility as Susan Crockford while admitting to not having her book. But as someone said, “that’s just me”.

      Richard

    • Kristi.
      It is good to be skeptical
      Most folks just accept what susan says.
      Looking at here choices in data, I would be suspect.
      I’m unconvinced by either side.
      like a good skeptic

      • Really YOU, skeptical these days?

        I know I don’t have to read her book to know that her case, that Polar Bears are doing well in part BECAUSE of the thinner and less ice cover in the Spring time is a valid observation,
        because she has repeatedly in a number of blog postings showed using a LOT of published research, including Dr. Armstrup’s research, that Polar Bears are thriving despite the greatly reduced Summer ice cover, in part because by then the Bears have eaten the majority of calories for the year by early July.

        I don’t think you are being honest here because you don’t actually visit and read her postings on this.

    • Killer whales have hunted in the Arctic for as long as there have been Western observers there to see them.

      Whether an apparent increase since c. AD 1850 is real or an artifact of more Western and indigenous observers is debatable. It’s also possible that more killer whales enter the Arctic during warm cycles, or that there are simply more of them in recent centuries, for whatever reasons.

      They certainly like the cold, icy waters of the Southern Ocean and Antarctic.

  11. “According to NSIDC Masie ice charts shown below, there is exactly the same amount of ice in the Arctic Basin this year at the end of August – 3.0 mkm2 – as there was in 2012: ”

    MASIE is not suitable for year to year comparisons.

    WHY?

    1. Different data sources are used day to day, month to month, year to year.
    2. The ice extent is estimated by a HUMAN IN THE LOOP.
    3. The human in the loop makes subjective decisions and year to year the human decider can change.

    The data documentations makes this clear. DO NOT use MASIE for year to year comparision.

    next up you use DMI Thickness. This is not data. This is a model output.
    If you actually go to the trouble of comparing this model with a live view of the arctic you
    will see how wrong it it. Hint? the modelling product has not been calibrated against
    newer observations (in feild and satellite) of thickness. Even though it shows a near
    record low volume, I would not use it.

    try PIOMASS

    http://psc.apl.washington.edu/research/projects/arctic-sea-ice-volume-anomaly/

  12. This really won’t do: arctic sea ice area and extent are around second/third lowest in the satellite record and likely to finish there in a few weeks time… in other words arctic sea ice has not ‘recovered’ and is still in decline and the area in the CAB area of the arctic is about as low as it has ever been…

    Plus you just have to look at the state of that ice: there isn’t a solid slab of it anywhere…

    https://seaice.uni-bremen.de/data/amsr2/today/Arctic_AMSR2_visual.png

    another factor is the rapid retreat in the early part of the year from (e.g) the Alaskan coast…more bears than ever are getting stranded on land, hence the many news reports of them interacting with human settlement.

    I would say that since there is (just about) ice linking Svalbard to the main ice, for the first time at minimum in several years, bears will at least be able to reach Svalbard denning areas – something they have struggled to do in many recent years.

    • Ha ha, as usual Griff continues to ignore plenty of evidence of INCREASED Polar Bear numbers in the last 20+ years.

      He also ignores the well supported research science that for most of the Interglacial period, the Summer Arctic Ice pack was lower than now and even little to none for centuries, in the early Holocene. Yet Polar Bears are still here and so are their main food choice.

      You have been repeatedly shown several published science papers on this, you keep ignoring it, because you are a profoundly dishonest man.

      • Arctic Ocean sea ice cover during the penultimate glacial and the last interglacial

        https://www.nature.com/articles/s41467-017-00552-1

        “(The) last interglacial (Marine Isotope Stage 5e)…is a time interval when the high latitudes were significantly warmer than today. We document that even under such warmer climate conditions, sea ice existed in the central Arctic Ocean during summer, whereas sea ice was significantly reduced along the Barents Sea continental margin influenced by Atlantic Water inflow. Our proxy reconstruction of the last interglacial sea ice cover is supported by climate simulations, although some proxy data/model inconsistencies still exist.”

        Proxy data show problems with models. What a surprise!

    • Griff,

      As of yesterday, this year was third lowest for Sept 1. As with all lower years, 2019 was plagued by cyclones, the last of which hit on August 26. It’s just WX, not CO2. If an fourth molecule of plant food per 10,000 dry air molecules since 1850 is to blame, then why did Antarctic sea ice grow from 1979 to its maximum in 2014, while Arctic fell until 2012?

      Where this year will end up deepends on WX between now and whenever the minimum is observed. Here is how it stood yesterday, in 000 sq km, according to the NSIDC:

      2012: 3867
      2016: 4453
      2019: 4567
      2015: 4593
      2007: 4600
      2011: 4668.

      The rank for minima ended up:

      2012: 3387
      2007: 4155
      2016: 4165
      2011: 4344
      2015: 4433

      2008: 4590
      2010: 4615
      2018: 4656
      2017: 4665

      2014: 5029
      2013: 5054
      2009: 5119

      So the median for the past 12 years is about 4.6 million sq km. This year will come in under that, but that doesn’t indicate a down trend. The fact is that 2012 remains the low. Arctic sea ice hasn’t made a new, lower low since then, whereas from 1979 to 2012, it did so at least every five years. The trend will remain flat since 2007 and up since 2012.

      This year could finish second, third, fourth, fifth or sixth, depending upon WX, without affecting those trends.

      Sea ice is cyclic. For most of the Holocene, summer minimum was lower than now. The dedicated satellite record began near the high for the 20th century.

  13. “ice-free conditions in Parry Channel occurred naturally even before global warming” hasn’t there always been global warming? Oh, I know the author means “Global Warming”

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