“Steepest slope ever.”
By Steven Goddard
We have been hearing a lot about how the decline in Arctic ice is following the “steepest slope ever.” The point is largely meaningless, but we can have some fun with it. The Bremen Arctic/Antarctic maps are superimposed above, showing that ice in the Antarctic is at a record high and growing at the “steepest slope ever.” You will also note that most of the world’s sea ice is located in the Antarctic. But those are inconvenient truths when trying to frighten people into believing that “the polar ice caps are melting.”
There are several favorite lines of defense when trying to rationalize away the record Antarctic ice.
1. It is the Ozone Hole – which is also the fault of evil, American SUV drivers. That is a nice guilt trip, but sadly the Ozone Hole doesn’t form until August and is gone by December. Strike one.
The next one is to point out that some regions of the west side of the tiny Antarctic Peninsula have been warming. Never mind that the Antarctic Peninsula is an active volcanic ridge, and that the waters around it have not shown any significant warming. Strike two.
UAH shows Antarctica cooling slightly over the last 30 years.
The third favorite line of defense is to argue that “we expected Antarctica to warm more slowly because of the mass of the southern oceans.” Nice try – “slower warming” is not the same as “cooling.” Strike three.
(The AGW view of Antarctica is every bit as irrational as FIFA’s stand that not having instant replays somehow helps the referees’ reputations.)
On to the Arctic. First graph is a JAXA comparison of 2006, 2007 and 2010. Note that 2006 and 2007 were nearly identical, until early July. The main difference between 2006 (second highest in the JAXA record) and 2007 (lowest in the JAXA record) was that strong southerly winds compacted and melted the ice in 2007. As you can see below, the summer extent numbers are nearly meaningless before July/August. So far, 2010 is tracking very closely with both 2006 and 2007, and it appears the three will intersect in about a week.
Let’s take a closer look at the mechanisms using the PIPS ice and wind data. If we watch the movement of Arctic ice during the summer, we can see that when the winds blow away from the pole (i.e. from the north) the ice expands. When the wind blows from the south, the ice contracts. Some summers, the winds alternate between north and south, and the ice extent changes less during the summer – like in 2000 below.
Other years, like 2007, the summer winds blew consistently from the south, causing the ice to melt at a faster pace and compress towards the north.
So basically, it is weather (wind) rather than climate which controls the summer minimum. Of course, it is harder to compress and melt thick ice than thin ice – so the thickness of the ice is important. It is too early to determine if 2010 will see winds like 2007, or if summer winds this year will be more like 2006.
No one has demonstrated much skill at forecasting winds six weeks in the future, so it is really anybody’s guess what wil happen this summer. Before August arrives, the pattern should be clear.
The video below shows ice movement near Barrow, AK over the past 10 days.
The winds were blowing strongly and contracting the ice edge until the last few days, when they died down. Over the past two or three days, the ice edge has not moved very much.
Over the last week, almost all of the ice loss in the Arctic has been in the Hudson Bay, as seen in the modified NSIDC image below in red. The Hudson Bay is normally almost ice free in September, so the recent losses are are almost meaningless with respect to the summer minimum.
The modified NSIDCimage below shows ice loss since early April. All of the areas shown in red are normally ice free in September.
The modified NSIDC image below is a comparison of 2010 vs 2007. Areas of red had more ice in 2007. Areas of green have more ice in 2010.
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The modified NSIDC image below shows the current deficiencies in red. Again, all of those areas are normally ice free in September, so they don’t tell us much about the summer minimum.
Below is my forecast for the remainder of the summer.
But it all depends on the wind.
From the 9th century to the 13th century almost no ice was reported there. This was the period- of Norse colonization of’ Iceland and Greenland. Then, conditions worsened and the Norse colonies declined. After the Little Ice Age of 1650 to 1840 the ice began to vanish near Iceland and had almost disappeared when the trend re versed, disastrously crippling Icelandic fisheries last year.
The thick ice that has for ages covered the Arctic Ocean at the pole has turned to water, recent visitors there reported yesterday. At least for the time being, an ice-free patch of ocean about a mile wide has opened at the very top of the world, something that has presumably never before been seen by humans and is more evidence that global warming may be real and already affecting climate. The last time scientists can be certain the pole was awash in water was more than 50 million years ago.
Is it possible that the IPCC is trying to rewrite the history books?
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Rob R says:
June 28, 2010 at 4:34 pm
So perhaps the state of sea ice cover in the Arctic is not as bad as we have been led to believe?
Yes. That’s what always happens when someone checks in to global warming for themselves: they find it’s not what we’ve been told.
David says:
June 28, 2010 at 3:16 pm
I don’t think I’ve seen anyone claim that there hasn’t been ice loss over the past 30 years. Much of the discussion has revolved around how much can be read into short term ice loss trends and how they’re likely to relate to the potential September mininum. In this context I find your comment a little disingenuous Anu.
Let me check if I quoted the article above correctly:
Yup, that’s what it said.
Perhaps stevengoddard “meant” it is some combination of climate changing, plus hard-to-predict “weather” on top of that trend of disappearing Arctic summer sea ice?
Nope, sounds like he’s arguing it’s the “weather”.
So basically, it is weather (wind) rather than climate which controls the summer minimum.
Ah, it is the wind which controls the summer minimum. Good to know:
http://nsidc.org/images/arcticseaicenews/20090917_Figure2.png
Then why not 7.5 million sq. km. this summer minimum ? Is the wind incapable of duplicating what it did in 1980’s or 1990’s anymore ? Why ?
Perhaps David would like to explain how 40 years of changing “weather” has nothing to do with a changing climate:
http://iup.physik.uni-bremen.de:8084/amsr/ice_ext_n.png
Here is a quote with no attribution. Has a scientist actually said this – using the present tense? I doubt it, partly because ‘ice cap’ refers to ice covering land, and partly because I’ve nowhere read a scientific assessment that Antarctic ice as a whole is currently melting. IOW, isn’t this a straw man?
This hyperbole is definitely a straw man. Ozone depleting gases are not associated with SUVs. Of course, CFCs and the like are hardly limited to the US.
Steig’s paper agrees that Antarctica has cooled very slightly in the last 30 years. But it has warmed slightly if the record is extended to the last 50 – 60 – with strong caveats.
How? The scientific view is that most of the Antarctic is relatively thermally isolated from the rest of the world, and that a warming world will begin to influence the region more precipitously in a few decades. Those areas not isolated by the polar winds (peninsula), have warmed significantly. How is any of this irrational? Isn’t it, alternatively, irrational to imply that every region of the world should march in lock-step with every other? It would be easier to imagine the earth as a featureless billiard ball where regional change conforms all over, but the truth is more complex.
Steve Goddard says:
June 28, 2010 at 4:51 pm
Geoflynx
Using your logic we should be able to ignore the summer minimum.
GeoFlynx –
Why? I think I just said the Northern Hemisphere ice was the more important issue at this time and that the apparent balance mechanism in global sea ice that you cited was due to the seasons. I believe the indications, given by the state and trend of the cryosphere, should not be ignored.
Is there such a thing as an Atlantic La Nina?
Like a 3.4 off the African coast.
SouthAmericanGirls says: June 28, 2010 at 3:40 pm
“Excellent post. But I still do not know what PIPS mean.”
PIPS in the U. S. Navy’s Polar Ice Prediction System. PIPS 2.0 is the current version that’s publicly available:
http://www7320.nrlssc.navy.mil/pips2/index.html
PIPS 3.o is “The most recent upgrade to the Navy’s ice prediction capability is the development of the next generation forecast system: PIPS 3.0. Improvements to this new forecast system include higher horizontal resolution, a more sophisticated ocean model, improved data assimilation and perhaps most important, an improved sea ice model, based on the Los Alamos CICE model. This sea ice model will include a Lagrangian formulation for calculating a multi-category ice thickness distribution, a snow layer, a brine pocket parameterization, non-linear profiles of temperature and salinity (Bitz and Lipscomb, 1999). The CICE model is presently being tested by NRL with Navy Atmospheric forcing from the Navy Operational Global Atmospheric Prediction System (NOGAPS). This model will be coupled to Navy Operational global ocean models. These improvements are geared towards providing better forecasts of formation and lead orientation. The PIPS 3.0 is presently going through its final development.”
Here is the PIPS 3.0 website, which doesn’t appear to have been modified since “01 August 2003”:
http://www.oc.nps.edu/~pips3/
Anu says:
June 28, 2010 at 2:39 pm
Hey, it’s just the wind, and nobody can predict that, right ? The planet has been “cooling” for 15 years, and PIPS 2.0 shows “thick” ice all over the Arctic Basin. The Arctic sea ice will be partying like it’s 1989 this September, no doubt.
VILLABOLO SAYS:
Hey Anu, I’ll bring the beer for the PARTY. You can bring some of the “thick ice” to chill it. Hope it’s not rotten!
This is the time the summer extent can be predicted. Right now the slope looks moderate but we’ll have to wait until the extent reaches 8sqkm. If the slope of the extent is highly negative then, it will be a small extent. If it flattens out, it will be a large extent. Let’s just wait.
Mauibrad says:
June 28, 2010 at 5:18 pm
“American Physicist Joins Attack on Global Warming Theory”
http://news.suite101.com/article.cfm/american-physicist-joins-attack-on-global-warming-theory-a255036
Dr. Charles R. Anderson makes his announcement on his website (June 28, 2010) in joining a growing band of professional scientists, international academics and climate experts prepared to put their reputations on the line and denounce the orthodox views held by an influential clique of discredited government climatologists.
The catalyst for the sudden willingness to speak out against the once widely accepted theory of global warming may be an impressive new online publication, ‘A Greenhouse Effect on the Moon?’ by Dr. Martin Hertzberg, Alan Siddons and Hans Schreuder.
This looks very important (I navigated to the paper on the moon – not being a black body) and points to a component in global heat budget that has been ignored – heat storage of the land surface. OK there is more sea surface and water has more heat capacity. But land surface heating / cooling and storage / re-release of heat cannot be ignored. (The fact that temperature in caves is taken as an integrator of recent climate temperature – thus stalagtites can be used as climate proxies, tells us this also.)
http://wattsupwiththat.com/2010/05/26/in-which-i-go-spelunking/
Land is where people live and where ice ages happen. The earth just like the moon is nowhere near being a black body. Land contributes (with the sea) to global thermal inertia and also to earth temperature being much higher than predicted by black body calculations – no need for CO2 to exclusively explain this.
Waiting for the necessary data to actually make informed conclusions about ice and climate is like watching two snails race.
Oh well .. at least I won’t miss much while I go to the concession stand. :-p
At a presentation within the last couple of years, His Goreness claimed that *both* polar ice caps would be completely melted away within five years or so.
Hey Al, how many polar ice caps are there? Answer: There’s only one, and it’s in Antarctica. Although there’s a lot of sea ice at the N Pole, there is no ice cap there. There are ice caps at relatively high latitudes in the N hemisphere: a big one in Greenland, and a small one in the S half of Iceland.
the trolls are about
Mike says: June 28, 2010 at 4:09 pm
“See http://www.guardian.co.uk/environment/2009/jan/21/global-warming-antarctica
Scientists have solved the enigma of the Antarctic apparently getting cooler, while the rest of the world heats up.”
It’s very hard to take this article seriously as it is clearly Warmist propaganda, e.g. “Research ‘kills off’ climate sceptic argument” “Scientists have solved the enigma” “it is the final piece in the jigsaw.” etc. Furthermore the study cited within is by Eric Steig, a Geochemist at the University of Washington and a member of the Real Climate team:
http://www.realclimate.org/index.php/archives/2004/12/eric-steig/
http://www.realclimate.org/index.php/archives/category/extras/contributor-bios/
I am however pleased that we are getting to some of the sources of the ignore Antarctica meme. Can anyone cite a study supporting the Warmist position on Antarctica that wasn’t penned by someone from the University of Washington;
http://psc.apl.washington.edu/zhang/Pubs/Zhang_Antarctic_20-11-2515.pdf
and who isn’t also responsible for this;
http://psc.apl.washington.edu/ArcticSeaiceVolume/IceVolume.php
garbage model?
Google search for “the polar ice caps are melting” (in quotes) returns about 81,900 results
GeoFlynx
The anomaly data is normalised. The fact that the global anomaly data has remained constant has absolutely nothing to do with seasons. That is one reason why people normalise data – to remove cyclical behaviour.
GeoFlynx says: June 28, 2010 at 3:23 pm
“A good mechanism for the above observation would be: it’s winter in the Antarctic when it’s summer in the Arctic. Climatologists claim that Northern Hemisphere ice cover and extent has a greater effect on global temperature than ice in the Southern Hemisphere. The sum of both ice fields may not be a good indicator of climate change.”
You state that, “Climatologists claim that Northern Hemisphere ice cover and extent has a greater effect on global temperature than ice in the Southern Hemisphere.” Can you please cite these climatologists and supply links to the relevant studies supporting your assertion?
The point being that winter ice extent, well you could put that where the sun don’t shine. The extent during the summer tho, that has a significant effect on the albedo, and thus the heat input into the region since the absorption of water for solar radiation is considerably higher than that of ice. The ice extent in the south during summer has been falling, and the extent during summer in the north, well that has fallen off the cliff.
Now I have to ask are you just trolling Anu?
Do you assert that in any given year that localised weather conditions are not likely to have a significant impact on the September minimum ice extent. Do you really assert this?
Have you ever seen me argue anywhere on any thread that climate will not change?
Let me make a few points clear so you cannot misinterpret Anu.
Yes, I do believe our climate has changed over the past 30 years just has it has over the entire history of this planet.
Yes I do believe we have seen some degree of warming over the past 30 years in that a predominantly positive PDO has lead to a higher frequency of el-nino conditions leading to a very strong 98 el-nino and this has contributed to a gradual loss of multi-year ice in the Arctic.
No I don’t believe the entire blame for this is atributable to man-made CO2 emissions nor do I believe them to be the main driver although I do accept that CO2 has contributed to a minimal degree.
Yes I do believe natural climate cycle variations have been the main driver of ice loss over the past 30 years.
Yes, I do believe that in a given year, localised wind and ocean currents play a significant role in determining the September minimum extent. Although I would highly suspect the average over the past 10 years has been lower due mainly to the previously mentioned 30 years of warming and the after effects of the very strong 98 el-nino which I believe was the main driver in the current lack of multi-year Arctic Ice.
Finally and most importantly, I would argue that large differences in the degree of ice loss from month to month are more likely to be attributable to localised conditions rather than trying to argue they demonstrate any sort of long term trend.
When you look at the 2007 result it is clear the massive extent of the ice loss was not the norm and was more due to an unusual confluence of localised Arctic conditions. Sure the warming of the past 30 years made the ice more vulnerable and exacerbated things but how often do those localised conditions that caused the actual ice loss in 2007 occur? The recoveries of 2008 and 2009 I think clearly demonstrate this. No death spiral.
So there’s more ice in the Antarctic and less in the Arctic. Total volume at the poles is a wash.
I wish someone could explain to me what’s the downside of less arctic ice and more antarctic ice. Seems to me it would be great to have the high northern latitudes warmer. Every little bit extends growing seasons and expands total arable acreage. It would be great to have a reliable NW Passage too. Save a lot of time and fuel in intercontinental shipping. Colder at the south pole – who cares? That’s a good place for the ice. Not like the Anarctic continent is ever going to be warm enough to grow corn or apples.
http://en.wikipedia.org/wiki/Polar_ice_cap
Larry Fields,
The terminology is problematic, but according to wikipedia there are two polar ice caps on Earth. If Gore claimed that both would melt away within five years or so, he is/was wrong. Where did he make that claim? Is it documented?
Does anybody know when we will see data from cryo sat 2?
http://www.esa.int/esaLP/ESAOMH1VMOC_LPcryosat_0.html
From the 9th century to the 13th century almost no ice was reported there.
It was even warmer on earth 6000 years ago than then.
The Wet Sahara:
Southern sea ice has more impact on earth’s albedo than northern hemisphere ice, because Antarctic ice forms at lower latitudes.
Also, the southern peak positive anomaly occurs at the summer solstice, whereas the northern hemisphere peak negative anomaly occurs at the equinox, when it has no effect on the earth’s radiative budget.
Claims that Arctic ice is somehow more important than Antarctic ice are simply incorrect.
stevengoddard says:
June 28, 2010 at 6:57 pm
Google search for “the polar ice caps are melting” (in quotes) returns about 81,900 results
And Google search for ‘climate skeptics are crazy’ returns about 163,000 results.
What’s your point ?
That Google sure does search all kinds of sites ?
Bob Tisdale in his latest post points out that the North Atlantic and Arctic ocean heat content has been rapidly falling since 2005. In fact it is responsible for most of the rise and decline in global OHC over the last 30 years. The previous rapid rise from 1998 to 2005 correlates with the accelerated decline in arctic sea ice extent and volume.
http://bobtisdale.blogspot.com/
Bob speculates that the OHC decline may continue for twenty more years. This should make the warmists nervous.