Jennifer Marohasy

a forum for the discussion of issues concerning the natural environment

What Drives Change in Antarctic Sea Ice Cover?

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THE modern meteorologist relies on computer models for forecasting. Coupled atmospheric-ocean models, known as general circulation models, are favoured for medium to long-range forecasting with these models forecasting an overall and quite rapid general warming at the north and south poles. In accordance with this forecast, there has been a general decline in the extent of sea ice at the Arctic. At the Antarctic, however, sea ice has increased in extent, at least over the period of the satellite record, Figure 1.[1] Sea Ice Cover

I’m interested to know what might have driven the overall decline in the sea ice at the Arctic, and increase at the Antarctic, over the last thirty or so years. According to mainstream climate science, increasing levels of atmospheric carbon dioxide would drive the melt. But what would drive the increase?

A long-range weather forecaster who relies on a knowledge of solar and lunar cycles, rather than computer models, is Kevin Long. He claims that when there is more sea ice at the Antarctic there is generally below-average rainfall and heavier late season frosts in central Victoria.[2]

In an explanation of the origins of our understanding of the Southern Oscillation, which the mainstream climate science community believes has a major affect on rainfall over eastern Australia, Donald R. Mock from the US National Oceanic and Atmospheric Administration (NOAA) suggests early researchers dismissed any direct influence of solar activity on the phases of the Southern Oscillation, but took an interest in the possibility of a connection with the polar circulation particularly the extent of sea ice at the Antarctic [4]. Nowhere in this explanation, however, is an extraterrestrial link, whether lunar, solar or planetary, offered.

A fellow I know who takes an interest in solar-terrestrial physics because his business of installing radio and television antennae depends on it, claims a relationship between the global sea ice anomaly and lunar cycles. In particular, Siliggy claims that the global sea ice anomaly goes up when the moon is new at apogee and down when the moon is full at apogee.[3] On January 1 and January 30, 2014 there was synchrony between perigee and the new moon.[3]. I can’t see a period when there is synchronoy between new or full moons at apogee until March 5, 2015, when the moon will be full at apogee.[3]

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[1] Ole Humlum Climate4You update for January 2014 http://www.climate4you.com/Text/Climate4you_January_2014.pdf
[2] Kevin Long summer forecast http://thelongview.com.au/documents/FORECAST-2014-No1-SUMMER-Kevin-Long.pdf
[3] The moon orbits the earth in an ellipse, not a circle, and so there are period when it is closer (perigee) and further away (apogee) in each one-month cycle. Also during this cycle there are periods when the moon is the same side of the earth as the sun (new moon) and on the opposite side of the earth to the sun (full moon). For new and full moon phases and perigees and apogees for 2014 see Lunar perigee and apogee calculator at https://www.fourmilab.ch/earthview/pacalc.html
[4] The Southern Oscillation: Historical Origins by Donald R. Mock, written 1981. http://www.esrl.noaa.gov/psd/enso/misc/hxsoi.html

Reader Interactions

Comments

  1. cohenite says

    “I’m interested to know what might have driven the overall decline in the sea ice at the Arctic, and increase at the Antarctic, over the last thirty or so years. According to mainstream climate science, increasing levels of atmospheric carbon dioxide would drive the melt. But what would drive the increase?”

    Polar oscillation:

    http://scrippsscholars.ucsd.edu/rkeeling/content/northern-ice-discharges-and-antarctic-warming-could-ocean-eddies-provide-link

    Discussed here:

    http://www.princeton.edu/~cmngroup/13_Science_Editors_Choice.pdf

    See also:

    http://wattsupwiththat.com/2010/03/28/skating-on-the-other-side-of-the-ice/#more-17856

    http://wattsupwiththat.com/2012/10/24/nasa-on-earths-bipolar-sea-ice-behavior/

  2. spangled drongo says

    Refreshing honesty from Prof Ian Simmonds from the U of Melbourne at the current International conference on sea ice in Hobart this week:

    “Now, to answer your question directly: we’re still trying to work out the impacts on the Southern Hemisphere continents. We can see some signals there and there are tantalising links to suggest that what’s happening around Antarctica can impact on the onset of El Niño events, which in turn impact on Australian rainfall.

    As you know, when we have an El Niño, the eastern half of the country receives much less rainfall. Now, at the moment this work is really just beginning; we’re just beginning to put the story together of these remote associations.”

  3. Another Ian says

    Jen,

    I’ll just remind Prof Ian Simonds that rainfall in our part of eastern Australia has been “seriously impacted” for the last couple of years – without an el Nino.

    So I hope his “remote associations” cater for known conditions

  4. Neville says

    Over the years the Arctic and Antarctic see saw effect is mentioned. Some scientists claim it’s always the case that the two poles are always opposite and there will always be more ice at one when the other has less. Who knows?

  5. Robert says

    Our driest decade in the record was the decade without a B0M-defined El Nino: the 1930s. As I’ve said before, the heat/drought/fire of 1938-9 occurred during a La Nina flanked by ENSO-neutral years. There was one El Nino (BoM defined) in the twenty years between 1919-20 and 1940-01 El Ninos. Yet we know how dry eastern Australia was in those decades. During our wettest decade, the 1970s, there were two El Ninos (after El Nino 1969-70).

    Surely that’s worth thinking about. Ian Simmonds is not wrong in saying El Nino spells less rain for eastern Oz. But so, obviously, do a bunch of other things.

  6. spangled drongo says

    If Antarctic sea ice in the Bellingshausen Sea has suffered a considerable melt there must have been a huge build-up around the rest of that continent to make the global anomaly ~ normal in recent times:

    http://www.climate4you.com/images/NSIDC%20GlobalArcticAntarctic%20SeaIceArea.gif

    IPCC AR5 admit they haven’t got a clue:

    “Overall we conclude that there is low confidence in the scientific understanding of the observed increase in Antarctic sea ice extent since 1979, due the larger differences between sea-ice simulations from CMIP5 models and to the incomplete and competing scientific explanations for the causes of change and low confidence in estimates of internal variability.”

    But Luke will tell us that it is all SAM’s fault and as deep ocean temperatures around Antarctic rise, they increase ice shelf melt. This meltwater is creating a cool layer near the surface of the ocean that promotes sea ice production. In addition, the meltwater is fresh, or much less salty and dense than surrounding saline ocean layers. So fresher meltwater floats upward, mixing with the cold surface layer, lowering its density. As this fresh layer expands, it forms a stable puddle on top of the ocean that makes it easier to produce and retain sea ice.

    That right, Luke?

    But Judith Curry makes a very good point:

    “Notwithstanding the simulations by climate models that reproduce the decline in Arctic sea ice, more convincing arguments regarding causes of sea ice variations requires understanding and ability to simulate sea ice variations in both hemispheres.”

    IOW if they know so little about the Antarctic sea ice, why should we believe they know any more about the Arctic sea ice?

  7. handjive of climatefraud.inc says

    E.M. Smith or ‘Chiefo’ did a post on cycles that might have some detail of relevance:

    “The earliest discovered historical record of the saros is by the Chaldeans (ancient Babylonian astronomers) in the last several centuries BC.
    But clearly “folks new” and for a very long time. This mattered to them. I think it very unlikely to have been only due to superstition. I’d point out, for example, that the PDO cycle looks to be about 3 x Saros. The “Polar See-Saw” may also be a related cycle.”

    Chiefo has a lot more detail at link:
    Lunar Cycles, more than one…
    http://chiefio.wordpress.com/2013/01/04/lunar-cycles-more-than-one/

    Why Weather has a 60 year Lunar beat
    http://chiefio.wordpress.com/2013/01/24/why-weather-has-a-60-year-lunar-beat/

    A good read anyway.

  9. Avatar photojennifer says

    Just filing this note from Kevin Long here:

    “It is my understanding that the Arctic sea ice up to about 5 years ago was declining at a slightly faster rate than the Antarctic was gaining sea ice on average.

    But during the last five years Arctic sea ice has been becoming more stable, and during the last Arctic summer a 50% increase was recorded in the summer minimum.

    At present the winter maximum is about to be reached at about 4% below the 34 year Mean.

    Whereas on the 20th Feb the Antarctic reached it summer minimum at 25.6% above the 34 year mean. And since that date a rapid growth has started again, about 10 days earlier than usual.

    This gives a global average of 1% above the 34 year mean at present, which indicates the global sea ice extent has recovered from the melting episode that was brought about by the recent highest solar radiation levels for 8000 YEARS (1940 to 1980) Ocean heat storage provides about a 15 year delay before full effects are recorded.

    During the times of high solar radiation the greater land area of the NH absorbs more heat energy and melts more ice.

    Whereas in the SH with only about a third of the land area to absorb the heat, much lower average temperatures are recorded, resulting in a faster sea ice growth. And slower melt rates

    A second reason why Antarctic ice can grow so quickly is it is not contained, it has an almost unlimited area to spread into, only the rate of melt at the perimeter controls it’s spread.

    If you take a look at the SSTsourounding the antarctic this year you will see very little sea that is above average, in fact world wide there is very little above average SST, whereas about 4 years ago when the antarctic sea ice was melting down to a 34 year minimum, the southern oceans were mostly well above average. Which was part of the season why 2010/11 recorded the wettest two years in the BOM’s records.

    The Arctic sea ice once it reaches about 14 million sq klms runs out of space to grow into, and can only grow in limited area’s that are much further away from the north pole, hence the potential maximum sea ice area is reduced by the land area in the Arctic circle and beyond.
    When the summer HEAT returns the extra heat from the warmer land in the region helps to melt the sea ice quicker.

    There is good correlation that the years close to the minimum lunar stand still are years of above average sea ice both in the NH and the SH.

    The strongest and wettest La Nina years of the 18.6 year lunar cycle occur, when;

    1 the moon is coming down from maximum stand still (25 degrees declination) and reaches 23 degs south of the Equator on the new moon phase. With the sun is also close to 23 degs south position,
    With the moon directly between the sun and earth, King tides in the sea, King tides in the land (LARGE EARTH QUAKES and King TIDES in the AIR, producing flood rain events like those that occurred in Brisbane two years in a row at that stage of the cycle.

    If this occurs within an active monsoon season, with planets producing a close perigee moon, 300 to 400% of monthly rain usually results.

    2 if the synodic cycle of Jupiter and Saturn is also closely synchronised with the lunar cycle at the same time a theoretical 297 year flood extreme is produced. (the 2010/11 floods)

    3 Nine years later a theoretical one in 297 drought year is very likely. That year should be dryer on average than 1982, the direst year on record in CENTRAL VIC, so far. Two cycles previous.

    4 When the Bicentennial solar Minimum cycle is close to it’s lowest point an extended drought lasting decades is likely to be produced.

    Low solar radiation = cooler sea’s, cooler sea’s = more sea ice, cooler sea’s = less humidity = less rain more sea ice = cooler drier southern weather systems.
    More sea ice = more frosts. The higher the average sea ice, the less average rain falls in the MDB.

    Ends.

  11. siliggy says

    Hi Jennifer
    Thanks for mentioning the EMR effects of the sun.
    Here are two goverment links that give a lot of info in a quick viewing for those who are curious (one U.S and. one Aussie). For more info ask nearly any ham radio operator to tell you about skip and the sun (then try to stop them talking).
    http://www.ips.gov.au/HF_Systems/1/1/1
    http://www.fcc.gov/encyclopedia/why-am-radio-stations-must-reduce-power-change-operations-or-cease-broadcasting-night
    I think the sun modulates via the changing angle and efficiency of ionospheric refraction, the amount of both natural and man made HF and VHF EMR that enters and leaves the planet.
    More on the sea ice moon thing later but it does not seem to be radio related but rather simple optical reflection.

  12. Glen Michel says

    Antarctic sea ice variability versus Antarctic continental ice loss ; strange ,incongruent whatever .I’ll take any explanation and consider all but will be not convinced necessarily;viccisitudes of Erda and its celestial accompiances I suppose.Fact or fiction?

  13. Neville says

    I suppose we should link to the Pages 2K study again and highlight some of the differences for earlier Antarctic warming compared to today.
    As I’ve noted before Antarctic was warmer from 141 AD to 1250 AD and a warm spike from 1671 to 1700 and was coldest in the study in the middle of the 20th century.

    http://web.science.unsw.edu.au/~sjphipps/publications/pages_2k_consortium2013.pdf

    But even the Arctic and Europe had warmer periods earlier in this study. The warmest period for the Arctic was in the earlier 20th century 1941 to 1970 and cooler from 1971 to 2000.
    So before co2 could have had an impact ( IPCC before 1950) we find that the Arctic temp was higher and 1971 to 2000 was lower.
    This just backs up the Jones, Vinther and Briffa Greenland temp study. In South America the 1971 to 2000 temp was similar to 1250 to 1271. Europe temps were higher from 741 to 770 AD and from 21 to 80 AD than today. See page 342 of the study.

  14. Siliggy says

    How the moon effect theory goes.
    The moon reflects light at us from the sun. The amount we get via the moon is way way lower than the amount we get straight from the sun but it is not zero. If it were zero or even close to it we would not be able to see it nor would we see the difference between a bright moonlit night and a pitch black moonless night. During the night the light from the moon is the most significant amount we do get. The Arctic and Antarctic nights are long and it only takes a very small variation over this long time to change the temperature from freezing to not freezing when it is right at the threshold. At the edges of the ice it is right at the threshold. So it is only simple logic that says on a night when the moon is both full and close it will be slightly warmer than on a night when there is no or little moonlight. Also a close moon should be brighter and therefore warmer than a far away moon.

  15. Neville says

    Jennifer asks what drives Antarctic sea ice cover? What we can say for sure is it isn’t increased emissions of co2, because there is just no evidence this is the case.

    But we still have Henry, Garnaut etc telling the OZ electorate that our reduction of 5% of 1.2% of the planet’s emissions is the best way to fight climate change. Of course this is just in time to help Labor and the Greens in the re-run of the WA senate election. Big surprise NOT.
    But we now have the latest RS and NAS report telling us that even if we could cease ALL human emissions of co2 today it still couldn’t alter the climate for thousands of years.

    As the Bolter points out Abbott’s direct action plan is the better by far of the twin evils offered to the electorate and it would be far better for business and jobs into the future.

  19. Neville says

    This extra accumulation above could be another reason why SLR as measured by the gauges has been decelerating recently in a number of studies.

  20. Neville says

    Ten years ago a Schmidt and Shindell study informed us that Antarctica had been cooling since the 1970s, but some of the temp record shows no warming since the 1950s.
    But don’t worry because C/models show this COULD turn around in the coming decades and it MAY warm again.
    Yet all the models show Antarctica will be negative for SLR for the next 300 years. So take your pick.

    http://web.archive.org/web/20041015162038/http://www.giss.nasa.gov/research/news/20041006/