MASIE: “high-resolution, accurate charts of ice conditions”
Walt Meier, NSIDC, October 2015 article in Annals of Glaciology.

Something strange is happening in the reporting of sea ice extents in the Arctic. I am not suggesting that “Something is rotten in the state of Denmark.” That issue about a Danish graph seems to be subsiding, though there are unresolved questions. What if the 30% DMI graph is overestimating and the 15% DMI graph is underestimating?

The MASIE record from NIC shows an average year in progress, with new highs occurring well above the 2015 maximum:

Meanwhile from NOAA’s Sea Ice Index (SII) dataset we get this:
The monthly average January 2016 sea ice extent was the lowest in the satellite record, 90,000 square kilometers (35,000 square miles) below the previous record low in 2011.

Why the Discrepancy between SII and MASIE?

The issue also concerns Walter Meier who is in charge of SII, and as a true scientist, he is looking to get the best measurements possible. He and several colleagues compared SII and MASIE and published their findings last October. The purpose of the analysis was stated thus:

Our comparison is not meant to be an extensive validation of either product, but to illustrate as guidance for future use how the two products behave in different regimes.

The Abstract says:
Passive microwave sensors have produced a 35 year record of sea-ice concentration variability and change. Operational analyses combine a variety of remote-sensing inputs and other sources via manual integration to create high-resolution, accurate charts of ice conditions in support of navigation and operational forecast models. One such product is the daily Multisensor Analyzed Sea Ice Extent (MASIE). The higher spatial resolution along with multiple input data and manual analysis potentially provide more precise mapping of the ice edge than passive microwave estimates. However, since MASIE is based on an operational product, estimates may be inconsistent over time due to variations in input data quality and availability. Comparisons indicate that MASIE shows higher Arctic-wide extent values throughout most of the year, largely because of the limitations of passive microwave sensors in some conditions (e.g. surface melt). However, during some parts of the year, MASIE tends to indicate less ice than estimated by passive microwave sensors. These comparisons yield a better understanding of operational and research sea-ice data products; this in turn has important implications for their use in climate and weather models.

http://www.igsoc.org/annals/56/69/a69a694.pdf

The whole document is informative and worth the read.
For instance MASIE is described thus:

Human analysis of all available input imagery, including visible/infrared, SAR, scatterometer and passive microwave, yields a daily map of sea-ice extent at a 4 km gridded resolution, with a 40% concentration threshold for the presence of sea ice. In other words, if a gridcell is judged by an analyst to have >40% of its area covered with ice, it is classified as ice; if a cell has <40% ice, it is classified as open water.

The fact that MASIE employs human judgment is discomforting to climatologists as a potential source of error, so Meier and others prefer that the analysis be done by computer algorithms. Yet, as we shall see, the computer programs are themselves human inventions and when applied uncritically by machines produce errors of their own.

The passive microwave sea-ice algorithms are capable of distinguishing three surface types (one water and two ice), and the standard algorithms are calibrated for thick first-year and multi-year ice (Cavalieri, 1994). When thin ice is present, the algorithms underestimate the concentration of new and thin ice, and when such ice is present in lower concentrations they may detect only open water. The underestimation of concentration and extent of thin-ice regions has been noted in several evaluation studies. . .Melt is another well-known cause of underestimation of sea ice by passive microwave sensors.

The paper by Meier et al. is a good analysis, as far as it goes. In this post I will show the gory details and bring the comparison up to date.

Detailed Comparison between SII and MASIE

Here is a graph comparing SII and MASIE over the last decade and in the last year:

 

The green line shows the SII deficit to MASIE each month averaged over the last 10 years. The red line shows a cumulative surplus of ice reported by MASIE running through the 12 months, averaged over the last 10 years. Clearly, the graph shows SII underestimates ice extent most of the year, but by September the discrepancy is minimal. Then a huge surplus of ice is reported by SII each October, which results in SII reporting a higher annual extent than MASIE.

But look at what is happening recently.

The blue line shows the SII monthly deficit to MASIE in 2015, while the purple line shows the MASIE surplus during 2015. SII last year underestimated extents more than previously, and with a smaller correction in October, MASIE shows an annual surplus, the cumulative divergence for 2015 is about 2M km2 above the 10 year average.

And in 2016, SII results are increasingly untrustworthy. January 2016 is 450k km2 down, and February (so far) is 600k km2 less than MASIE.

Conclusions

It is unwise to rely on NOAA’s Sea Ice Index as a sole measurement of Arctic ice extent.

The October SII readings are unbelievable, and resemble an adjustment applied to bring the annual results into line.

The MASIE record is good enough for Walter Meier to analyze it with the objective of making SII closer to MASIE’s accuracy.

 

Addendum:

Here are the tables so you can see the numbers:

2006-2015	2006-2015	2006-2015	2006-2015	MASIE Surplus
Averages	MASIE	SII	SII Deficit
January	13.87	13.78	-0.09	0.09
February	14.79	14.63	-0.15	0.25
March	15.01	14.89	-0.12	0.37
April	14.31	14.31	0.00	0.37
May	12.77	12.96	0.19	0.17
June	10.95	11.19	0.24	-0.07
July	8.40	8.42	0.02	-0.08
August	6.07	5.84	-0.23	0.14
September	4.79	4.88	0.09	0.05
October	6.74	7.69	0.94	-0.89
November	9.98	10.12	0.15	-1.04
December	12.24	12.35	0.11	-1.15
12 month Ave.	10.83	10.92	-0.10

	2015	2015	2015	MASIE Surplus
Averages	MASIE	SII	SIIDeficit
January	13.94	13.62	-0.32	0.32
February	14.68	14.43	-0.25	0.57
March	14.67	14.39	-0.28	0.85
April	14.12	13.96	-0.16	1.01
May	12.65	12.65	0.00	1.01
June	10.84	10.97	0.13	0.88
July	8.71	8.77	0.06	0.82
August	5.96	5.61	-0.35	1.17
September	4.68	4.63	-0.05	1.22
October	7.05	7.72	0.67	0.55
November	10.34	10.06	-0.28	0.83
December	12.43	12.27	-0.16	0.99
12 month Ave.	10.84	10.757	0.08

	2016	2016	2016
	MASIE	SII	MASIE-SII
January	13.92	13.47	0.45
February	14.77	14.17	0.60

Recently when accessing MASIE for the daily ice extent update, I noticed this statement in the left margin of the home page:

NSIDC has received support to develop MASIE ice extent but not to maintain MASIE. We are actively seeking support to maintain the product over the long term. If you find MASIE helpful, please let us know with a quick message to NSIDC User Services.

So I sent them a message of appreciation:

To: nsidc@nsidc.org<nsidc@nsidc.org>;

Update below February 22, 2016

Needless to say, “Ice Free” never happened.  It is true that in the last ten years, August and September monthly extents declined slightly, but the other ten months have increased more than twice as much.  So the over all trend has been slightly upward.

Here is the current image from NASA:

 

For comparison, here is the ice chart from MASIE:

 

 

The comparable MASIE image is showing about 500k km2 more ice than the NASA image. Through mid February, 2016 is following the average winter ice growth over the last ten years, and is greater than 2015 which had a maximum below average. The NSIDC Ice Index is running behind MASIE by about 600k km2.

It remains to be seen in March how this year’s maximum will compare to other years.

Update February 22, 2016

Some additional information on the MASIE ice product:

MASIE: Human analysis of all available input imagery, including visible/infrared, SAR, scatterometer and passive microwave, yields a daily map of sea-ice extent at a 4 km gridded resolution, with a 40% concentration threshold for the presence of sea ice. In other words, if a gridcell is judged by an analyst to have >40% of its area covered with ice, it is classified as ice; if a cell has <40% ice, it is classified as open water.

The passive microwave sea-ice algorithms are capable of distinguishing three surface types (one water and two ice), and the standard algorithms are calibrated for thick first-year and multi-year ice (Cavalieri, 1994). When thin ice is present, the algorithms underestimate the concentration of new and thin ice, and when such ice is present in lower concentrations they may detect only open water. The underestimation of concentration and extent of thin-ice regions has been noted in several evaluation studies

Melt is another well-known cause of underestimation of sea ice by passive microwave sensors.

Meier et al. How do sea-ice concentrations from operational data compare with passive microwave estimates? Implications for improved model evaluations and forecasting

Click to access a69a694.pdf

 

 

 

 

 

People are duped by false alarms about Arctic sea ice because they have (subliminally) bought into the notion likening the Arctic to their home refrigerator. This post is to dissuade you from taking on board that false analogy.

Inside Your Fridge
When you put liquid water into your fridge, it releases heat, both sensible and latent, the air in the compartment warms and the heat engine extracts the warming to maintain a constant temperature.

The energy is substantial: it takes 417 kj per kilogram of water to go from room temperature (20C) to ice or vice-versa. The math from Wikipedia is:

To heat ice from 273.15 K to water at 293.15 K (0 °C to 20 °C) requires:

(1) 333.55 J/g (heat of fusion of ice) = 333.55 kJ/kg = 333.55 kJ for 1 kg of ice to melt
PLUS
(2) 4.18 J/(g·K) × 20K = 4.18 kJ/(kg·K) × 20K = 83.6 kJ for 1 kg of water to increase in temperature by 20 K
= 417.15 kJ

And of course if you leave the door open, the refrigeration unit is unable to remove the heat efficiently, the freezing process slows and less ice is produced. Also when electric power is lost, everything frozen starts melting and perishable food spoils.

Alarmists sometimes say that when the jet stream wanders south from the Arctic (“the polar vortex”), it is like leaving the fridge door open and sea ice will be lost as a result. This is upside down and backwards, since the Arctic does not at all resemble a refrigerator.

Inside the Arctic
In the Arctic (and also at the South Pole), the air is in direct contact with an infinite heat sink: outer space. The tropopause (where radiative loss upward is optimized) is only 7 km above the surface at the poles in winter, compared to 20 km at the equator. There is no door to open or close; the air is constantly convecting any and all energy away from the surface for radiation into space.

Instead of an open door, Arctic ice melts when the sun climbs over the horizon. Both the water and air are warmed, and the ice cover retreats until sundown in Autumn.

Most people fail to appreciate the huge heat losses at the Arctic pole. Mark Brandon has an excellent post on this at his wonderful blog, Mallemaroking.

By his calculations the sensible heat loss in Arctic winter ranges 200-400 Wm2.

As the diagram clearly shows, except for a short time in high summer, the energy flow is from the water heating the air.

“Then the heat loss over the 2×109 m2 of open water in that image is a massive 600 GW – yes that is Giga Watts – 600 x 109 Watts.

If you want to be really inappropriate then in 2 hours, that part of the ocean lost more energy than it takes to run the London Underground for one year.

Remember that is just one component and not the full heat budget – which is partially why it is inappropriate. For the full budget we have to include latent heat flux, long wave radiation, short wave radiation, energy changes through state changes when ice grows and decays, and so on. Also large heat fluxes lead to rapid sea ice growth which then insulates the ocean from further heat loss.”

The Key Difference
The really big paradigm shift is to understand that the sea ice extent itself regulates the periods of warming and cooling air temperatures, and not the other way around. Of course, there is a considerable lag, on the order of several decades, as you would expect in any system with massive capacity and momentum. Zakharov (here) shows how Arctic ice functions as a self-oscillating system:

Summary: Why the Arctic is not a Refrigerator

1.  A fridge makes ice by keeping the air below freezing.
The Arctic makes ice by keeping warmer water away.

2.  Ice melts in a fridge when warmer air is allowed in.
Ice melts in the Arctic when the sun shines.

3. The fridge is regulated by an air temperature sensor.
The Arctic is regulated by the ice extent itself.

 

The media and warmists ignore Arctic ice in wintertime because they are obsessed with the summer melt, and hoping for lots of open water.  In fact, ice extent trends are basically driven by the freezing this time of year, while Sept. extents vary greatly due to summer weather events, not climate change.

The press has been reporting some storm activity in the North Atlantic, and tossing words like “unprecedented” into the stories.  But keeping things in perspective, we can say that the freezing is going normally with the usual day to day fluctuations.

January and February show an average year in progress:

 

Conclusion:

Do not trust mass media for unbiased reporting of climate news.

Some people don’t like the unalarming patterns of ice extents displayed by MASIE, and hang onto obsolete comments about times in the past when ice charts were inconsistent.  Today’s MASIE dataset is accurate and reliable, according to NSIDC who expressed confidence when releasing it in 2015.

About MASIE produced by NIC (from NSIDC)

The NSIDC Sea Ice Index ice extent is widely used, but the edge position can be off by 10s or in some cases 100s of kilometers. NIC produces a better ice edge product, but it does not reach the same audience as the Sea Ice Index.

In June 2014, we decided to make the MASIE product available back to 2006. This was done in response to user requests, and because the IMS product output, upon which MASIE is based, appeared to be reasonably consistent.
Note:  Presently, NSIDC Sea Ice Index is showing ~700,000 km2 less ice extent than MASIE.

We are currently treated to another expose of the Climate Scare Machine doing its job. Perhaps you’ve seen these eyeball-grabbing headlines in the last week.

Freak storm in North Atlantic to lash UK, may push temperatures over 50 degrees above normal at North Pole @Washington Post

Arctic ‘heatwave’ hits the North Pole: Storm Frank causes temperatures to soar by 60°F taking the icy region close to melting point @Daily Mail

Arctic ‘heat wave’ sets new record low for sea ice @The Weather Network

These rumor mills start with a factoid, in this case an unusual weather event. Then some know-nothing “journalists” look for quotes from scientists who should know better, but want to grab attention with a sound-bite. Then the editors are off to the races making up headlines to raise circulations and advertising rates.

So, there was a storm called Frank, and it did push warm, moist air toward the North Pole.  From NSIDC (here)

The event was linked to the combination of a very strong low pressure system near Iceland and a somewhat less intense low pressure system located near the North Pole. . . This created a strong, deep inflow of warm, moist air into the Arctic Ocean’s high latitudes. The low near Iceland strengthened rapidly in the last days of December, reaching a minimum pressure of 935 millibars, equivalent to a hurricane. While the event was remarkable and may account for the slow ice growth during the first few days of January 2016, it was short lived and is unlikely to have any long-term effects on the sea ice cover.

And yes, there was a pause in the rate of ice growth in December.

Here is MASIE data for the last 16 days (Dec. 21 through Jan. 5) compared to averages for the last decade. You can see the pause, and then the acceleration of ice growth in 2016, moving almost 400k km2 above average.

Conclusion:

Do not trust mass media for unbiased reporting of climate news.

And they are pulling the same trick, hoping to melt the Greenland ice sheet by blowing hot air over it.  What you need to know:  Greenland is Melting! Really?

About MASIE produced by NIC (from NSIDC)

The NSIDC Sea Ice Index ice extent is widely used, but the edge position can be off by 10s or in some cases 100s of kilometers. NIC produces a better ice edge product, but it does not reach the same audience as the Sea Ice Index.

In June 2014, we decided to make the MASIE product available back to 2006. This was done in response to user requests, and because the IMS product output, upon which MASIE is based, appeared to be reasonably consistent.

Footnote:

Maybe if all that hot air could be captured, it could be useful, like this:

But wait!  That hot air appears to be rising, rather descending to melt the ice. Hmmm.

Update January 3, below.

This year end report shows there is no reason to worry about Arctic ice melting. Against the odds, 2015 recovered from:
The blob melted Bering Sea a month early; it’s now well ahead of 2014.
An August storm pushed extent down for 28 days; it now nearly matches 2014.

MASIE measurements show that 2007 ice extent was lower than any year since. It is now confirmed that 2015 average annual extent exceeds 2007 by about 400,000 km2. That difference arises from comparing 2007 annual average of 10.414 M km2 with 2015 average through day 365 of 10.808. That makes 2015 virtually tied with 2009 for fourth place in the last ten years.

Summary:

Arctic ice declined in the decade prior to 2007, but has not declined since.

Alarmists chafe at the words “growing” and “recovery”, and I use them poetically to counter “death spiral” terminology. What we have seen in the last decade is a plateau in Arctic ice extent, analogous to the plateau in surface temperatures. The rise since 2007 is slight and not statistically important, just as the loss of ice from 1979 to 1994 in the NOAA dataset was too slight to count as a decline.

Note:   Something unusual happened in the MASIE record.  After increasing ice extent steadily at a rate of 87k km2 per day after Dec. 10, MASIE stopped showing growth and declined a bit after Dec. 23.  Ice extent was lost in Kara, Barents and Greenland Seas.  That allowed NOAA extent to catch up and reduce its deficit.  Previously, NOAA showed ~400k km2 less than MASIE, that difference being typical historically.  For the year NOAA shows about 200k km2 less than MASIE, both at year end and for the annual average.

MASIE Comparison 2014 and 2015 Day 365

Ice Extents			Ice Extent
Region	2014365	2015365	km2 Diff.
(0) Northern_Hemisphere	13330376	13027597	-302778
(1) Beaufort_Sea	1070445	1070445	0
(2) Chukchi_Sea	966006	965989	-17
(3) East_Siberian_Sea	1087137	1087120	-17
(4) Laptev_Sea	897845	897809	-36
(5) Kara_Sea	935023	876266	-58757
(6) Barents_Sea	641686	342398	-299288
(7) Greenland_Sea	619029	557954	-61075
(8) Baffin_Bay_Gulf_of_St._Lawrence	1023477	1181297	157820
(9) Canadian_Archipelago	853214	853178	-36
(10) Hudson_Bay	1260903	1260723	-181
(11) Central_Arctic	3245389	3202967	-42422
(12) Bering_Sea	255711	373594	117883
(13) Baltic_Sea	7527	2850	-4677
(14) Sea_of_Okhotsk	454321	345063	-109258
(15) Yellow_Sea	4475	4312	-163
(16) Cook_Inlet	130	4490	4360

The small overall difference between 2014 and 2015 at this point matches the deficit in Barents Sea. The major basins have recovered: Central Arctic,  BCE (Beaufort, Chukchi, East Siberian), Canadian Archipelago.  Bering Sea is freezing well ahead of last year, as is Baffin Bay, offsetting deficits elsewhere except for Barents.

Technical Note:  Changes in Ocean Water Structure drive changes in Arctic Ice Extent, and air temperature varies as a result, not the cause.

https://rclutz.wordpress.com/2015/12/23/arctic-sea-ice-self-oscillating-system/

 

 

Update January 3, 2015

Neven is the first to attack this post in comments below, followed by a post at his own blog in which he says:

“misleading and embarrassing statements”
“older gentleman”
“mind set in concrete”
“taken apart by Tamino”
“data misrepresentation”

And on cue Tamino’s (Foster’s) attack dogs are coming here.  Now I responded to all of Neven’s and Foster’s bogus objections in Sept. (here). Since they either did not read or did not understand, I will repeat the salient points again.

Warmists fail to see that having two different tracking methods for a climate phenomenon is a good thing.  With temperatures they favor the land surface record and abhor the satellite temps.  With Sea Ice they like the satellite reports and abhor the navigational observations.  JAXA, DMI, NORSEX and NOAA (or NSIDC) are all using data from passive microwave sensors on satellites to estimate ice extents.  Some  differences arise from differing algorithms at each center.

Naval authorities have for centuries prepared ice charts for the safety of ships operating in the Arctic.  There are Russian, Danish, Norwegian, and Canadian charts, in addition to MASIE, the US version.  These estimates rely on multiple sources of data, including the NASA reports.  Charts are made with no climate ax to grind, only to get accurate locations and extents of Arctic ice each day.

MASIE is not the only dataset to show this lull in Arctic ice decline. It is also obvious in Foster’s final graph.  I showed how the same pattern appears in the NOAA (technically NOAA@NSIDC) dataset (here).  Those who object that a decade is too short to claim a recovery were quick to claim a decline (even a “death spiral”) based on a decade-long loss of ice ending in 2007.

Some were upset that I used the MASIE data, despite NSIDC cautions against it.  For the record, the NSIDC Background cites as support a study by Partington et al (2003).  Reading that study, one finds that the authors preferred the MASIE data and said this:
“This analysis has been based on ice chart data rather than the more commonly analyzed passive microwave derived ice concentrations. Differences between the NIC ice chart sea ice record and the passive microwave sea ice record are highly significant despite the fact that the NIC charts are semi-dependent on the passive microwave data, and it is worth noting these differences. . .In summer, the difference between the two sources of data rises to a maximum of 23% peaking in early August, equivalent to ice coverage the size of Greenland.” (my bold)  For clarity: the ice chart data show higher extents than passive microwave data.

http://digitalcommons.unl.edu/cgi/viewcontent.cgi?article=1058&context=usdeptcommercepub

In any case, NSIDC’s last word was this:  “In June 2014, we decided to make the MASIE product available back to 2006. This was done in response to user requests, and because the IMS product output, upon which MASIE is based, appeared to be reasonably consistent.”  And thus, the data appeared this September.

 

 

Every winter day across the Northern Hemisphere millions of cross-country skiers rely on the settled science of snowflakes. The practical application involves the use of wax in order to “stride and glide” across the snow.

How does it work? You glide on the tips and tails of the skis, so you put on those spots a very hard wax, like paraffin, that makes little friction with the snow. When you put your foot down in order to stride forward, you need on the ski under your boot a more sticky wax that will grip the snow for traction.

The art and science of waxing means choosing the right wax for the existing snow conditions. Snow crystals have sharper points when cold and dry, and are more rounded when warm and damp. When snow is fresh, cold and dry, a harder wax will do the job. Snow that is older, warmer or damp, requires a softer, sticker wax for traction.

If you put on too soft a wax, you get a big clump of snow attached to your ski bottom, and you would do better with snowshoes. Norwegians have gotten quite expert at this and win a lot of Olympic medals racing cross-country, along with other Scandinavians and Russians.

Here in Quebec last century Cree natives were amazed to see a Norwegian flashing through the woods over the snow, and they gave him a nickname. Until recently you could still buy his waxes branded with his legendary name: “Jackrabbit Johannsen.” (In 1982, at the age of 107, Herman Smith-Johannsen (1875-1987) was inducted into the Canadian Sports Hall of Fame.)

Of course, when the snow gets deep and stays very cold as it does in the Arctic, it compacts into solid ice, part of the ebb and flow of Arctic Sea Ice extent. When the ice cover retreats, the air becomes moist from evaporation, snow falls and the ice grows. When extensive ice restricts open water, the dry air produces too little snow to replace ice melted by the sun, and the cycle begins again.

The science is described more fully in Arctic Sea Ice: Self-Oscillating System