By Steve Goddard
Last month, a number of well known web sites and commenters were getting themselves worked up with comments like “Arctic ice dropping at the fastest rate in history” and “Arctic ice is dropping like a rock.” I advised repeatedly that prior to July, looking at the extent graphs is pointless.
July is here now, and the rate of ice extent decline has dropped dramatically over the last week. To put this in perspective, according to JAXA data, the June 28-July 4 rate is -53361 km²/day. In 2007 during the same period, ice was lost at -123104 km²/day.
In other words, 2007 was losing ice 2.31X faster than 2010.
This can be seen most dramatically in the DMI graph, which measures only higher concentration ice (30%.)
http://ocean.dmi.dk/arctic/icecover.uk.php
Close up image below.
So why the dramatic difference in slope? One reason is that sea ice concentration is at the highest level in the satellite record. Compare below vs. 1980, when ice was considered very “healthy.” Current concentration is considerably higher.
Ice concentration is particularly important this time of year because the sun is relatively high in the sky. When the ice concentration is low, sun shines into the water in “Swiss Cheese” holes around the ice, warms it, and corrodes away the edges of the ice. This year, ice concentration has been close to 100% in most of the Arctic – which means very little sunlight is reaching the water in the Arctic Basin. As a result melt will occur more slowly than during low concentration years.
The videos below represent an exaggerated visualization of the process. The first video shows an idealized view of future Arctic Basin melt during 2010 – i.e. a single large circle of ice surrounded by water.
The next video shows what happens in years when the concentration is lower. The sun is heating the water between circles, and because of the smaller circles a much larger surface area of ice is exposed to warm water. Warmer water and more exposed surface area causes melt to proceed faster.
Conclusion : Cold temperatures, cloudy skies, favorable winds and high concentration ice – all point to continued slow melt over the next few days.
Anu
I think we can say with a high degree of certainty that the Arctic will not be ice free in 2016, and your word games are a waste of everyone’s time.
Anu says:
July 6, 2010 at 9:53 am
Yes, but we can see no such humility on your part. We didnt expect it either.
Right, kwik.
See Dick run. See Jane run. See Anu project.
Project, project, project.
IARC-JAXA AMSR-E Sea Ice Area
Berényi Péter
Excellent link! I hadn’t seen that one before. Worthy of an article.
Berényi Péter says:
July 6, 2010 at 10:44 am
Aha! Someone’s doing science all on their own! Will probably soon be a crime.
dbleader61 says:
July 6, 2010 at 8:38 am
For those that think R Gates should be sent away, I disagree. I find that his “skepticism” and counter discussion results in additional and clearer arguments for lay people like me from Steve Goddard and others. The exchange between them seems to be in the true spirit of scientific debate (with occasional equally spirited lapses) and I applaud Anthony for permitting it to take place on his blog.
__________
There was some discussion about “sending me away”?!!! To where would I be sent? Is this coming from Anthony? Have I offended the Skeptical Gods? What pray tell have I missed?!
Very exciting, we’re finally at theory meets facts time of year. . . I’ve been a proponent of the “concentration in the central core” importance (I think the differences between Steve and I are pretty minor on theory), and look forward to seeing how that plays out.
Steven Goddard
As you say the Berenyi Peter graph is great. If you do intend to write an article perhaps you could delve a bit more into the weather circumstances in April/May where 2010 went from leader of the pack to bottom of the class.
tonyb
R Gates
It’s Ok, several of us have decided we quite like you for some strange reason and were defending you against the charge of being a troll.
tonyb
Ken Hall:
“Surely that would make it a bigger stock of oil than Saudi Arabia and Iraq combined and therefore when the relief wells get into it, it would solve all Americas foreign oil problems for decades to come?”
The average productivity from all oil wells in the United States in 2008 was less than 10 barrels of oil per day.
http://www.eia.doe.gov/aer/txt/ptb0502.html
Businesses are in business for the purpose of making profits. That this exporatory oil well is still producing the amount of crude oil (and don’t begin to forget the huge amount of natural gas which is not being captured at all. Typically, the amount of methane in producing oil wells is about 4% of the total flow, and for this well it is higher than 40%) after some 75 days is rather astounding.
The new well BP is in the process of drilling is not a “relief” well in the usual sense of the term. Rather, their new plan, as I understand it, is to drill a hole (and of course case it properly this time) near to and parallel to the existing well, and then slant it to intercept the existing well. Then they can pump like the dickens to end the flow through the existing well, and hopefully plug the existing well above the point of interception (and below the point where the existing bore hole is obviously comprimised).
Mind you, my knowledge of hydraulic flow is of water, not oil, and water wells, but the principles are the same.
No point in my stating more, other than how very interesting. Fits quite nicely with having a tiger by the tail.
Berényi Péter’s linked graph of of sea ice area, 7/05/2010
The JAXA graph of sea ice extent, 7/05/2010
JAXA’s definition of the difference between area and extent:
tonyb says:
July 6, 2010 at 11:37 am
R Gates
It’s Ok, several of us have decided we quite like you for some strange reason and were defending you against the charge of being a troll.
tonyb
_________
Thanks for the support. I honestly had to look up the term on Wiki to see what it meant in terms of internet blogging. It would appear that if I simply posted: “You’re spot on Steve. Keep up the great independent research.” I would not be a “troll” but to play the role of skeptic of the skeptic, casts me as a potential troll.
I appreciate those who see a value in me contributing my perspectives on the issues.
R Gates
You’re welcome.
For your future information, we get a lot of trolls over here who come in all guns blazing, mimic the Real Climate party line, assume we’re all idiots out to trash the planet then disappear after people have taken considerable time and effort to refute their claims.
Reasoned scientific (or historic) debate is what its all about and personally I like to hear another perspective. Having said that we’ve yet to see this 25% scepticism you claim to have 🙂
tonyb
Pamela Gray says:
July 6, 2010 at 9:24 am
Another good one is “thanks for sharing”.
I keep thinking that a data display of the sea ice extent, concentration, or volume by concentric areas (like every 2 1/2 degrees) around the pole and extending southward to ~50N would tell you much more what the arctic and sea ice is actually doing day by day.
However, to do such an analysis you would need up-to-date and fine cell-by-cell data such as the historic data found on NSIDC site for concentration with 1/10th of a percent per cell and by the day.
Have you ever considered that if the data is actually available?
stevengoddard says:
July 6, 2010 at 7:09 am
“I have no idea what will happen in future years and have never made any claims otherwise.”
Steven, dont be shy! I think you can make a prediction for next summer;
http://www.accuweather.com/video/68856143001/global-warmth-getting-ready-to-collapse.asp?channel=vblog_bastardi
What about a minimum of not less than 6.5 pluss-minus 0.5 in summer 2011?
It seems possible.
tonyb says:
July 6, 2010 at 9:18 am
Nice graphs. Presumably it was a power point presentation but it goes much too fast for me and I can seee no way to go through each frame individually. Can you point me to the means to do that so I can examine each graph and keep as necessary?
Hi Tony,
You can find simple plots in the original put up by Antony :
http://wattsupwiththat.com/2009/12/12/historical-video-perspective-our-current-unprecedented-global-warming-in-the-context-of-scale/
It is a .gif animation and I think if you have photoshop you could save the animation and manipulate it but the individual plots exist in the link above.
I find it a very useful set for general and scientific audiences. It really gives a rational perspective and goes over well in lectures.
R Gates:
There was some discussion about “sending me away”?!!! To where would I be sent? Is this coming from Anthony? Have I offended the Skeptical Gods? What pray tell have I missed?!
_______________________________________________________________
This:
And it got squashed in a hurry.
A Hat tip to the good moderators here at WUWT, I wish all blogs were run this well.
_____________________________________________________________________
This:
Stephan says:
July 5, 2010 at 11:08 pm
I think R gates is one of many AGW trolls who has been instructed to try to “overcome” the Climategate problem by “appearing” to really know what he is talking about LOL but the answers here are not helping his cause so let him continue please…LOL. As I mentioned in previous posting some warmistas are going to be very surprised at NH minima this summer,
[REPLY – I don’t think he is being “instructed” by anyone. I just think he’s probably wrong. If Brother Gates wishes to argue climategate, he’s welcome to; most of us here have actually read the emails, anyway. He’s duking it out in “enemy territory”, which I can respect. Of course when we try that we tend to get censored rather heavily. #B^1 But Anthony and we mods here allow a free and open debate inasmuch as we can. We snip every now and then, but we do so at a minimum and tend to confine it to what we consider to be unduly abusive posts. ~ Evan]
ice area and ice extent in one page:
http://arctic-roos.org/observations/satellite-data/sea-ice/ice-area-and-extent-in-arctic
NSIDC July update is up, and offers some support to Steve’s ideas:
“However, it would not be surprising to see the rate of ice loss slow in coming weeks as the melt process starts to encounter thicker, second and third year ice in the central Arctic Ocean. Loss of ice has already slowed in the Beaufort and Chukchi Seas due to the tongue of thicker, older ice in the region noted in our April update.”
But really their July update reads to me as a “have it all ways” update, rather than them having enough confidence to stick a pin in a graph and say “here’s our best guess from what we’re seeing up to today”. But, if they don’t feel it, they shouldn’t say it, so I respect that.
As I read them, however, it would be leaning a little bit more than 51% towards the 2006 model without being willing to rule out the 2007 model just yet.
kwik
Given the current wind and temperature forecasts, it seems possible that this summer will come in at higher extent than I forecast. I am going to wait a week or two before updating my predictions though.
geo
Last month NSIDC was pushing PIOMAS, and this month seems to be headed in the opposite direction. I wonder if Julienne’s time over here influenced her thinking?
Anna v
Thanks for the link
tonyb
A note of caution on comparing sea ice concentrations from one day to another: it is well known that weather effects can bias the sea ice concentration, so picking a day from two different years may not reflect “true” changes in ice concentration. In addition, the differences in ice concentration may simply imply a change in surface melt rather than any real change in ice concentration. This is why NSIDC reports on changes in ice extent rather than ice concentration.
I am not surprised that the rate of decline has slowed a bit during the last week. In the Beaufort and Chukchi seas, the ice has essentially melted back to the lobe of old ice that was transported there over the winter (under the negative AO phase). Thus, this is slowing the ice loss in this region. In the Kara Sea, temperatures have been colder than normal and the winds are causing ice divergence (also helping to slow loss of ice extent in that region).
There has been a lot of talk that the fast rate of ice loss in June was a result of Hudson Bay melting out. Well, here are ice loss rates for the month for different regions and recent years:
Region 2007 2008 2009 2010 (1979-2000)
Chukchi -7,380 -3,310 -4,830 -6,430 -1,370 sq-km/day
Beaufort -1,900 -7,230 -3,450 -6,760 -670
E. Siberian -5,280 0 -1,220 0 0
Laptev -2,330 -410 -5,160 -3,810 -660
Kara -7,130 -5,610 -3,380 -8,920 -6,910
As you can see from the above regions in the Arctic basin, ice loss rates have been faster than normal everywhere except the E. Siberian Sea in 2010 and for the Beaufort, Laptev and Kara seas, ice loss rates in 2010 were faster than in 2007, and for the Kara Sea, this year shows the fastest ice loss rates in the last few years.