Sea ice news Volume 5, # 5 NSIDC: ‘the expansion in Antarctic sea ice is confirmed’

From NSIDC: Sled dog days of summer

NSIDC reports near record Antarctic sea ice extent in July

Arctic sea ice extent declined at a fairly rapid rate through the first three weeks of July, but the loss rate then slowed due to a shift in weather patterns. In Antarctica, the advance of sea ice nearly halted for about a week in early July, and then resumed. At the end of the month, Antarctic extent was at or near a record high for this time of year.

Overview of conditions

Antarctic sea ice extent map

July 2014 average ice extent was 8.25 million square kilometers (3.19 million square miles). This is 1.85 million square kilometers (714,000 square miles) below the 1981 to 2010 average for the month.

Ice extent is below average in nearly all sectors of the Arctic. Open water continued to grow in the Laptev and Beaufort Seas, reaching well north of 80oN in the Laptev Sea. By the end of the month, the Alaskan Coast was essentially free of ice except for small patches of very diffuse ice off Barrow. The Barents Sea, Hudson Bay, and Baffin Bay/Davis Strait are now essentially ice free. Large areas of low concentration ice in the central Beaufort Sea are likely to melt out in coming weeks. The Northwest Passage through the channels of the Canadian Arctic Archipelago remains choked with ice. Parts of the Northern Sea Route are still difficult to traverse because of high-concentration, near-shore ice between the Laptev and East Siberian seas and also north of the Taymyr Peninsula.

Conditions in context

sea ice extent graph

For July 2014 as a whole, ice extent declined at an average rate of 86,900 square kilometers (33,600 square miles) per day, close to the 1981 to 2010 average July rate of 86,500 square kilometers (33,400 square miles) per day. However, this averages together a fairly fast rate of decline over the first three weeks of the month with a slower rate of decline over the remainder of the month.

The slower ice loss later in the month reflects a shift in weather patterns. For much of the month, high pressure at sea level dominated the central Arctic Ocean and the Barents Sea. However, this pattern broke down and was replaced by lower-than-average pressure over the central Arctic Ocean. A low pressure pattern tends to bring cool conditions and the counterclockwise winds associated with this pattern also tend to spread the ice out.

July 2014 compared to previous years

sea ice trend graph

July 2014 is the 4th lowest Arctic sea ice extent in the satellite record, 340,000 square kilometers (131,000 square miles) above the previous record lows in July 2011, 2012, and 2007. The monthly linear rate of decline for July is 7.4% per decade.

More news on the Antarctic

Antarctic sea ice map

Antarctic sea ice graph

In our previous post, we noted that on July 1, Antarctic sea ice extent was growing rapidly, and could surpass the September 2013 record high extent (over the period of satellite observations). During early July, the advance of Antarctic sea ice extent nearly halted, but toward the end of the month, there was another period of rapid ice growth. Maximum extent is usually reached in September or October, at the end of the austral summer.

Many readers may be familiar with NSIDC’s Charctic interactive sea ice graph that allows one to plot daily Arctic ice extent for any year in the satellite record (1979 to present) and make quick comparisons with average conditions and between different years. NSIDC has recently added an Antarctic option to Charctic. We have done so in response to growing interest in Antarctic sea ice conditions and the very different behavior of Arctic and Antarctic sea ice. Just go to the Charctic site and click the button marked “Antarctic.”

Questions about data processing

algorithm comparison graph

A recent paper investigated the processing of Antarctic sea ice data and how this affects the interpretation of Antarctic ice extent trends. While their findings do not affect NSIDC’s analysis of Antarctic sea ice extent, as we use a different data set, it is an interesting example of scientific rigor regarding data, and it does affect other reports of Antarctic sea ice trends.

The paper studied the Bootstrap algorithm, which has been used in several published reports of Antarctic trends, including the last two IPCC Assessment Reports. These reports suggested that the Antarctic sea ice extent shifted from a small, statistically insignificant upward trend in the early 2000s to a more substantial, and statistically significant upward trend in recent years. (NSIDC uses a different algorithm, called NASA Team, to estimate sea ice extent.)

The paper found that following an update to the algorithm in 2007, using the newer Version 2 of the Bootstrap algorithm produced Antarctic sea ice extent trends that were approximately two times larger than those derived using Version 1. Closer examination of the data showed a noticeable step change in extent at the point of transition to a new satellite sensor in 1991. This step change appeared to be related to an error in calibration between the sensors, rather than actually being an abrupt shift in Antarctic sea ice.

Trends derived from both versions for time periods either before or after the sensor transition are similar. However, the two algorithms produce different results when trends that span the 1991 sensor transition are calculated. Using Version 2 of the algorithm produces a markedly higher trend.

Using the newer version of the algorithm, Antarctic extent trends agree much more closely with the trends from the NASA Team algorithm used by NSIDC. Regardless, the expansion in Antarctic sea ice is confirmed by other groups using different techniques.

References

Eisenman, I., W. N. Meier, and R. J. Norris. 2014. A spurious jump in the satellite record: has Antarctic sea ice expansion been overestimated?, The Cryosphere 8, 1289-1296, doi:10.5194/tc-8-1289-2014.

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For comlete up to date data, graphs, and images, see the WUWT Sea Ice Reference Page

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44 thoughts on “Sea ice news Volume 5, # 5 NSIDC: ‘the expansion in Antarctic sea ice is confirmed’

  1. Arctic sea ice extent declined at a fairly rapid rate…

    the old normal is now “fairly rapid”…..what agenda driven BS

  2. “Maximum extent is usually reached in September or October, at the end of the austral summer”

    ====================================

    Facepalm.
    .

  3. The real worry is if these people (AGW) simply do not accept what is happening and shut down the sites for public viewing. In my estimation this is almost a certainty in the coming months.
    http://ocean.dmi.dk/arctic/icecover.uk.php Watch this one VERY CAREFULLY as attempts will be made to force them to shut down or change the baseline

  4. Oh My Gaaad! how can this BS be published
    “July 2014 is the 4th lowest Arctic sea ice extent in the satellite record, 340,000 square kilometers (131,000 square miles) above the previous record lows in July 2011, 2012, and 2007. The monthly linear rate of decline for July is 7.4% per decade.”
    http://ocean.dmi.dk/arctic/icecover.uk.php Absolute trype!

  5. Eliza says:
    August 7, 2014 at 10:34 am
    ======================

    I screencapped it for posterity here.

    Almost touching the 1979 – 2000 average:

  6. Eliza and PhilinCalifornia – this is not an area I have followed much; help me understand what you are saying and why the differences in the various plots. Thanks.

  7. Very low daily melt rates in the Arctic since the mid-July. For a period of time in the third week of July, the 5 day melt rate was the lowest on record in my database going back to 1972.

    Jaxa and NSIDC daily melt rates.

    NSIDC’s September average minimum is coming in at 5.38M km2 versus 5.25M in last year’s recovery and 3.58M in 2012.

  8. Arctic sea ice extent declined at a fairly rapid rate through the first three weeks of July, but the loss rate then slowed due to a shift in weather patterns. 

    The main reason for the high, recovering summer Arctic ice minimum in September will be thick multi-year ice, not weather. However expect weather to be deployed increasingly as a fig leaf to hide embarrassment at the robust health of the ice, as we near the minimum.

  9. RE: Eric Simpson says:
    August 7, 2014 at 10:19 am

    Thanks for the compliment, Eric. Usually when I check my obscure site at lunch, and notice a flurry of visitors, I can trace it back to you.

    NSIDC has to put a brave face on the embarrassing situation they are in. It must be hard to work under Mark Serreze, and have to cover for his “death spiral” statements, and the fact he suggested the Pole would be ice free this summer.

    They fail to mention a few ways of noting the increase in the quality of the ice. Few are calling it “rotton ice” this year. If you compare “area” to “extent,” you note it is more densely packed, and if you check out the PIOMAS data for July you see the average thickness is 1.91 meters, thickest in five years, and the decrease since June was only 0.07 meters, which is the smallest July decrease in the past five years. In many ways we are heading back to pre-2010 levels.

    What the ice is teaching us is how swiftly it responds to the “cold” phase of the AMO. The AMO is not scheduled to turn officially cold for another five to ten years (as if the weather ever obeys human schedules) but it has had what most think is a temporary cold-spike the past ten months or so. If the AMO switches back to “warm” and the ice immediately starts shrinking on the Atlantic side, I think it will demonstrate the ice responds to oceanic cycles, not CO2.

  10. And in other Arctic news, DMI is still showing temps N80 still have not reached the average from 1958-2002.

  11. ‘A low pressure pattern tends to bring cool conditions and the counterclockwise winds associated with this pattern also tend to spread the ice out.’

    Isn’t this counter-intuitive as winds will tend to blow inwards towards an area of low pressure?

  12. I ran across Biomagnetism today in search of a geo-magneitic gestalt.

    Dipole is a muse micro and macro and logically the concern ‘Climate’?

  13. “The Northwest Passage through the channels of the Canadian Arctic Archipelago remains choked with ice.”

    This is setting up for Ship of Fools II.

  14. Surely they can show us the huge line of commercial ships about to ply the Northwest Passage sea lane in the ice free Arctic. /sarc

  15. “This step change appeared to be related to an error in calibration between the sensors, rather than actually being an abrupt shift in Antarctic sea ice.”

    Stupid is as Stupid does!

    Nothing to see here, move along.

  16. Caleb says at 11:24 am: …when I check my obscure site…

    Obscure site? That’s modesty for you. Lol. Everyone seems to have the highest of praise for the quality of your very detailed play by play reporting on the Arctic situation. And now it’s coming down to the wire as far as what the ice extent minimum is going to end up being. Time for people to tune in to your site.

  17. NSIDC: ” Using the newer version of the algorithm, Antarctic extent trends agree much more closely with the trends from the NASA Team algorithm used by NSIDC. Regardless, the expansion in Antarctic sea ice is confirmed by other groups using different techniques.”

    Which is of course the first thing that Eisenman et al should have done before publishing a speculative yet inconclusive paper casting doubt on the reliability of the Antarctic sea ice data.

    They were well aware that “Bootstrap” was not the only algorithm yet chose not look at ( or at least not to publish ) what would have taken very little effort to check.

  18. No problem , due to the ‘magic’ of C02 , both cold and hot can be caused by it , therefore both losses in ice cover and growth in are cover are both due to AGW.

  19. Caleb: “…. and if you check out the PIOMAS data for July you see …”

    PIOMAS is not data it is model output. A fairly broken model that did not give a hint of what happended to ice volume last year.

    Until they have NEW version that can at least reproduce 2013, there is little point in referring to PIOMAS output for anything.

  20. And if the ice grows too much, they can issue a press-release scare that the increase (caused by AGW) will lead to polar bear overpopulation and Malthusian starvation.

  21. For a science that has been so solidly settled as is climate change we’re certainly seeing an awful lot of new stuff lately. They must have turned up the government disinformation machine.

  22. “Maximum extent is usually reached in September or October, at the end of the austral summer.”

    Did NSIDC redefine the meaning of either “austral” or “summer”?

  23. Anything is possible says:
    August 7, 2014 at 10:31 am (quoting the original article)

    “Maximum extent is usually reached in September or October, at the end of the austral summer”

    Facepalm.

    Taphonomic says:
    August 7, 2014 at 1:26 pm (again quoting the original article)

    “Maximum extent is usually reached in September or October, at the end of the austral summer.”

    Did NSIDC redefine the meaning of either “austral” or “summer”?

    ====================================

    Odd statements. Why the questions (sarcastic rejoinders ?) at this claim?

    You’re reading a statement about the Antarctic sea ice extents, which DID set an all-time record high of over 2.05 million square kilometers of “excess” sea ice this past June. Antarctic sea ice hits its annual minimum in late February each year (just before Arctic sea ice reaches its yearly maximum in early April each year). Antarctic sea ice maximums hit their yearly high right in early October, right after the Arctic sea ice hits its yearly low in mid-September.

    The Antarctic winter is mid-season right now across the entire southern hemisphere, obviously exactly opposite the northern hemisphere summer. In fact, Australia has been setting record breaking cold temperatures in their July winter weathers as well.

    At minimum Antarctic sea ice extents, the yearly low has been steadily increasing – and is now right at 3.0 – 4.0 million sq kilometers. BUT….!

    Antarctic sea ice minimums occurs at latitude 68 south (on average) because the Antarctic sea ice extents surrounds the 14.0 Mkm^2 of antarctic land mass and the 3.5 Mkm^2 of fixed Antarctic shelf ice. The total Antarctic ice area then includes a “beanie cap” extending from the pole at 90 degrees south all the way to 68 south: In the northern hemisphere, this would be a line through the middle of Greenland, across all of Canada, below Alaska, across all of Siberia and north Russia, across Scandinavia, and back to the middle of Greenland. At the MINIMUM Antarctic sea ice extent.

    Thus, even at its minimum, the Antarctic sea ice reflects much. much more sunlight than the Arctic sea ice does at its yearly minimum. At its maximum in mid-September through through mid-October each year, the Antarctic sea ice edge receives (is able to reflect) 5 TIMES the solar energy that the edge of the Arctic sea ice up at 79-80 north latitude does.

    Because so much more solar energy hits the Antarctic sea ice edge than hits the Arctic sea ice edge, you cannot directly compare Arctic sea ice area to Antarctic sea ice area. even a “world total sea ice area” is misleading. Rather you need to multiply the Antarctic sea ice anomaly by a factor of 0.3 to 5.0, THEN add it to the Arctic sea ice anomaly to compare the total energy reflected from the sea ice between the two. That multiplication factor varies by day-of-year and hour-of-day (solar elevation angle, the earth’s axial tilt, solar top-of-atmosphere radiation values, and the sea ice edge vary by each hour of each of the year. Bottom line, seven months of the year, the Antarctic sea ice receives more energy than the Arctic sea ice does, and seven months of the year each square meter of Antarctic sea ice reflects more energy than does the Arctic sea ice.

    Making things worse: the Arctic sea ice is often multy-year ice, and thus is much dirtier than the “new” Antarctic sea ice. Judith Curry measured sea ice in the Arctic through the summer up there, and found than the mid-summer Arctic sea ice has an albedo of only 0.46 – 0.42 June-July-August. (Fresh snow and fresh sea ice as in the Antarctic is much higher at 0.85 – 0.90 albedo. ) By early September, the Arctic ocean at the edge of the Arctic sea ice at latitude 79-80-81 north that the Arctic ocean loses more energy by increased evaporation, increased conduction, increased convection and increased longwave radiation from the newly exposed arctic ocean than it gains by increased sunlight.

    Arctic sea ice extents hit their yearly minimum in mid-September – it is a date of celebration for the climate community because only arctic sea ice loss is “following the script” of catastrophic global warming these days. Every other one of their predictions has been proved wrong by the numbers, so receding Arctic sea ice is the only thing left that their religion can cling to.

    But as usual, they are missing the bigger story.

  24. Owen says:
    August 7, 2014 at 12:49 pm

    And if the ice grows too much, they can issue a press-release scare that the increase (caused by AGW) will lead to polar bear overpopulation and Malthusian starvation.

    Nah.

    At the last 4 years rate of growth, the Antarctic sea ice will block the Strait of Magellan and Cape Horn (up at 56-57 south latitude) within 8-12 years.

    Now, the edge of the Antarctic sea ice maximums “only” get as far north as latitude 58-59 south.

  25. RACookPE1978 says:
    August 7, 2014 at 1:46 pm

    Anything is possible says:
    August 7, 2014 at 10:31 am (quoting the original article)

    “Maximum extent is usually reached in September or October, at the end of the austral summer”

    Facepalm.

    Taphonomic says:
    August 7, 2014 at 1:26 pm (again quoting the original article)

    “Maximum extent is usually reached in September or October, at the end of the austral summer.”

    Did NSIDC redefine the meaning of either “austral” or “summer”?

    ====================================

    Odd statements. Why the questions (sarcastic rejoinders ?) at this claim?
    ************************************************************************

    Because it should read “at the end of the austral WINTER”

    SteveT

  26. “Arctic sea ice extent declined at a fairly rapid rate.” Really? As compared to…what? How many years have been measured to get an “average rate”? I don’t know the answer, but is it really an average considering the earth is over 4 billion years old?

  27. Am TOTALLY confused. And I am probably an idiot since I am having trouble sifting between the sarcasm and the science in these posts. Someone please help out here – using 3rd grade language that I can (probably) understand.

    What’s actually happening in the Arctic this summer? Posts on other sites show a dramatic SLOWING in the summer ice melt that brings us back very near the average ice extent for the past 20 years or so. (Danish scientists?) That is VERY different than the post above/

    What gives?

  28. Patrick B says:
    August 7, 2014 at 11:02 am
    Eliza and PhilinCalifornia – this is not an area I have followed much; help me understand what you are saying and why the differences in the various plots. Thanks.
    ===========================
    I’m not sure I totally understand the question, but the reason I screen captured the graph earlier today was to freeze (ha ha yes, pun intended) today’s data on this thread.

    Eliza’s links are to a “live” site that is updated, usually daily so, if you look at it on August 8th, 9th etc., it will be different from today (it’s still the 7th here in California).

    Also, the graph in this particular link of Eliza’s looks different for the reasons stated at the bottom of the graph (related to masking of coastal zones, whatever that means technically).

    http://ocean.dmi.dk/arctic/old_icecover.uk.php

    I hope this helps.

    In general, I was pointing out that Arctic ice is clearly recovering and, when combined with Antarctic ice extent, this may be a proxy for the fabrication of global temperatures by the climate liars.

  29. Greg says:
    August 7, 2014 at 12:41 pm
    Caleb: “…. and if you check out the PIOMAS data for July you see …”

    PIOMAS is not data it is model output. A fairly broken model that did not give a hint of what happended to ice volume last year.

    Until they have NEW version that can at least reproduce 2013, there is little point in referring to PIOMAS output for anything.
    ================

    Nylo says:
    August 5, 2014 at 12:43 am

    Spectacular reduction in the sea ice volume anomaly in the arctic during the month of July, which adds support to the most optimistic predictions regarding the sea ice extent that we may have in September.

    https://sites.google.com/site/arctischepinguin/home/piomas/grf/piomas-trnd3.png

  30. Imagine no CO2 anomaly
    I wonder if you can
    No anthropogenic global warming
    a hockey stick in the bin
    Imagine all the scientists
    discovering nothing wrong
    you ,you may say I,m a dreamer
    but i,m not the only one
    and I believe the sun will warm us
    guess,we must wait for the turn.

    Imagine tropospheric weirdness,
    The way that hot things go
    Those crazy molecules flying
    just as high as they can go
    Imagine just how cold it gets there
    50 miles above the sea
    You can call me a denier
    but its logic as far as i can see
    negating laws of thermodynamics
    and telling lies to all you see.

    Stratospheric influence is neglected
    lonely photons running free
    down welling forces hyperactive
    reaching for an equilibrium
    beyond the earth and the sea
    Imagine other theories
    El Nino and the AMDO ooo oo
    You ,may say i,m a denier
    Insolation does not heat
    Earth is frozen -18
    and its CO2 that causes heat .

    humble apologies to JL

  31. RACookPE1978 says:
    August 7, 2014 at 1:46 pm
    “Odd statements. Why the questions (sarcastic rejoinders ?) at this claim?”
    [regarding comments on NSIDC’s statement: “Maximum extent is usually reached in September or October, at the end of the austral summer.”]

    Note NSIDC’s use of the phrase “austral summer” and the time period to which it refers. You note in your extensive reply that it is currently winter down under as everyone except NSIDC seems to understand. Austral summer is commonly defined as December-February, rather than a period ending in October (which is commonly noted as the end of austral winter). One would think that NSIDC would be able to get such a simple concept straight.

  32. RE: polarbearscience says:
    August 7, 2014 at 12:30 pm

    That is a very nice overlay of the two Canadian Ice Service maps on you site, Susan.

    I don’t like to see any ice in Hudson Bay this late. Even if it melts soon, the water in the bay will be cold and off to an early start, when refreezing begins in October. Although many do not appreciate the fact, the waters of Hudson Bay keep New England warmer in the winter, until they freeze over. (We are also protected by the Great Lakes to our west.) Once Hudson Bay freezes over, a big nor’easter roaring up the coast and then stalling over Labrador can result in a direct discharge of the coldest arctic air straight south, and, because Hudson Bay no longer warms that north to south flow, New England gets the “Montreal Express,” and we see our coldest, record-setting temperatures, down near minus-thirty Fahrenheit, (and colder to the north.)

  33. The Earth has been Expanding for millions of years and this on going expansion has caused seas to recede constantly. The Earth Expansion phenomenon has evidently been mistaken for Post Glacial Rebound. Earth Expansion has been ongoing for millions of years. The Isostatic Rebound Theory was formulated less than 200 years ago. It is evident, therefore, that Earth Expansion is the reality and Post Glacial Rebound is a mistaken concept. It all started when Charles Darwin observed what he termed to be “Raised Beaches”. He thought that the land was rising from the sea. Darwin was wrong and his error was compounded by the likes of Jameison and Agassiz. Following on Darwin’s mistaken deduction they stated. “The reason that the land is rising from the sea is because it is rebounding from the weight of the last Ice Age.” There is no truth in the Isostatic Rebound Theory and therefore the Ice age is also suspect. For confirmation on the reality of receding seas contact the State of New Jersey and ask them what lessons they have learned about the receding seas. See all my videos on “The Mysterious Receding Seas” on youtube. I am Richard Guy

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