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Comments 151 to 200 out of 208:

151. Camburn at 09:01 AM on 1 July, 2011
     Philippe: I won't go into harmonics or cycles as most folks want to dismiss them. With that said, that is what I am using to base my low ice extent on. The area, volume etc. Cryosat, along with the Gatlin team has found ice thicker than previously thought unless one examines polar 5 data. The trend is as expected based on other criteria to me. The big elephant in the room is the amount of black carbon that China continues to spew. That has lowered ice albedo, and is ingrained in the ice itself. This has added to the degree of melt in a substantial way. BC is anthro in nature, so must be added to effect and cause. Shindell
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     Response:

     [DB] I would caution you on hanging one's hat on the initial rollout of Crosat-2 data.  In software terminology, it is only a "beta".  As a test, consider that the design vertical resolution is in the millimeter range, while the product delivered to date has a horizontal granularity (it has very large pixels) in the kilometer+ range.

     Adding to the calibration issues is a highly mobile, fractured and friable ice pack that is continuously shifting, adding to the issues in stitching together data from the separate flight paths.

     A layman interpretation is that the current realization of Cryosat-2 data is that it is nearsighted, needing visual corrections to come.  Future iterations will likely have improved discrimination capability as the stitching algorhythms evolve (it's eyesight will sharpen).

152. Camburn at 09:06 AM on 1 July, 2011
     michael: I would suggest that you get a copy of Capt Henry Larson's log on his voyage traversing the NW passage in 1944. I cannot post a link to his log as it is not available on the web and the museum, the owner of said log, has not given me permission to scan and post it.
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153. Camburn at 09:17 AM on 1 July, 2011
     This paper is one that examines long term Arctic Ice via the use of bowhead whale fossils. Dyke, Hooper, Savelle
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154. michael sweet at 09:22 AM on 1 July, 2011
     Camburn: includes observations from Capt. Larson's passage. You will have to provide actual data and not a reference to anecdotal evidence that you cannot show ("pay no attention to the man behind the curtain Dorothy"). If you cannot provide evidence to support your position you should go over to WUWT where you will be welcome. Here we want to see data. Rhis graph does not show the minimum, but it is clear what the trend is. Where do you see "harmonic trends" with your eyecormeter? I see flat before 1955 and unrelenting, exponentially increasing decline since then.
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155. michael sweet at 09:23 AM on 1 July, 2011
     My graph was from Cryosphere Today (linked in the main post).
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156. Camburn at 09:27 AM on 1 July, 2011
     michael: I have given you the source of Capt Larsons logs. He made the voyage..his anecdotal is pretty good as it is observation. The RCMP is a very professional organization. You may purchase the log book from the Museum in Vancouver, British Columbia. They have an online area that allows one to have the book shipped.
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157. michael sweet at 09:32 AM on 1 July, 2011
     My computer will not open your link. Please copy the relevant data (as I did) and post it here. Please point out what you think is important, a link without description is against the comments policy. I will not think cycles that are more than 1,000 years old are important without substantial evidence. I have provided strong evidence of a change in the Arctic Sea ice over the past centuary, please provide similar evidence to support your wild claims.
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158. michael sweet at 09:34 AM on 1 July, 2011
     Your anecdotal evidence is included in my graph. You will need to find data that supports your position. I cannot be responsible for your inability to support your position. In any case, anecdotal evidence is unscientific compared to the summary graph I have provided.
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159. Eric the Red at 09:41 AM on 1 July, 2011
     Phillipe, Sorry for the rant. Yes, 2007 saw an accelerated decline in June which has not occurred this year. Remember, the North Atlantic is particularly cold this year, and will not provide warm waters to increase melt. Michael, How did Cryosphere Today obtain its sea ice values? The sea ice off Iceland appears to be much more variable. http://www.arctichost.net/ICASS_VI/images/01.11.09.pdf
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160. michael sweet at 10:00 AM on 1 July, 2011
     Eric, The Cryosphere Today graph has no attribution on their page. They are often referred to as the experts on this data by other experts like the NSIDC. I presume the graph is their own summary of their data. They carefully take all the records that are available and compile them into their graph. Places like Pond Inlet, Barrow and many other locations have long records. Data from explorers like Scott and whalers are also inlcuded. Ice in any local area will of course be more variable than ice in the entire Arctic Basin. (Iceland is not even in the Arctic Basin). It is common for there to be a lot of ice in Alaska when there is less ice in Svalbard and visa versa.
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161. michael sweet at 10:07 AM on 1 July, 2011
     Eric, It is incredible to see how you can find optomism in this data! You should write a post for WUWT. Neven has done a much more through analysis than your unsupported eyecrometer and he thinks the sea temperature is warmer in the Kara Sea than 2007, and comparable elsewhere. We will have to wait a week for the NSIDC report to come out, they will have the true word. Why are you skeptical of the Cryopshere Today data, you rarely provide data of any type yourself.
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162. Camburn at 10:12 AM on 1 July, 2011
     Bowhead Whale Study: http://pubs.aina.ucalgary.ca/arctic/Arctic49-3-235.pdf Michael: Here is the website where you can order the book. Funny how a voyage done in 1944 through the northern northwest passage, logged and completed isn't evidence. Vancouver Maritime Museum
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163. michael sweet at 10:14 AM on 1 July, 2011
     Camburn, You have not summarized the data at all. I have provided you the data and summarized it for you. You link to a paper that does not even talk about the last 100 years when AGW has started its influence (since Bowhead whales were hunted out in 1910). You have not even said what you think is important in the paper you linked or how it applies to our discussion. What should I look for when I read it? Where is their graph showing "harmonic cycles" that apply on a yearly scale? You have brought nothing but gibberish to the table. We all know the indigeneous people will be severly affected. You are the one minimizing those effects. Your paper supports my position that the change is unprecedented. Try to find a paper that actually supports your position and not mine, it will be difficult.
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164. michael sweet at 10:17 AM on 1 July, 2011
     Camburn, You have not even produced a single line from your book as evidence to support your wild claims. You tell me to buy and read an entire book without even citing a page that supports your position??? If you have no data to support your position you should admit it and stop wasting everyones time.
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165. Camburn at 10:25 AM on 1 July, 2011
     Michael: I called the librarian at the museum to get permission to do what you asked. That permission was denied. Part of their revenue is sales of the logs. They want people to buy the book. I will not go against their wishes as I respect law. The book is worth the money and a very nice addition to any library. I gave you my reasons for my prediction, as crazy as you must think it is, of approx 3.5 for the low this year. We will see how close I come. I provided you links to published literature showing the varation in the Arctic Ice on a historical scale. We know it was not variation in TSI that caused the variation in the ice.
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166. Camburn at 10:28 AM on 1 July, 2011
     Michael: One thing I have learned in all my years is to present evidence, and not inflict my interpretation of the evidence until the other person has read the paper. I do not want to taint your understanding. Once it has been read and digested by someone else, then we can have a good gentleman's discussion about what each understands. You are a smart feller, you don't need me to tell you what you should think of a link that I post for your knowledge.
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167. michael sweet at 10:46 AM on 1 July, 2011
     Camden, the University of Calgary here summarizes Larsons expedition. It took him 86 days to make the passage in an icebreaker that had been equipped with a larger engine that year. At the end of July ice forced him to run up the coast of Greenland and not Baffin Island. He could run up Baffin Island today, a full month earlier. Last summer a fiberglass daysailer that was incapable of breaking 1 cm of ice made the passage in only about 21 days, after making the North east passage the same summer. The St Roch (Larson's vessel) was reported almost crushed by ice at Tuktoyaktuk and in the Bearing Sea in September. The Corsair 31 would have been destroyed by any ice at all. Find a reference that supports your posititon. The reference you have provided shows that there was much, much, much more ice in 1944 than there is today. If you cannot support your position with data stop posting gibberish.
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168. scaddenp at 10:49 AM on 1 July, 2011
     Eric, well its good to see you do have some guidelines even if you would wait 26 years for the result. Wouldn't that be rather embarassing because if the theory is right, and we wait 26 years before doing something about it, then we would be rather up the creek by then and leaving a terrible legacy behind. As to what would convince me that something was seriously wrong (or more to the point,missing) in climate theory, well that is straight forward. Climate theory makes a large no. of predictions with varying degrees of robustness concerning a large no. of variables. A breech of any robust prediction means model fixing at very least. I would want to discover an unknown natural forcing before I started betting on it. The truly convincing step would be an alternative theory for climate, consistent with all known physics, that makes a better job of accounting for observations that our present one.
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169. scaddenp at 11:00 AM on 1 July, 2011
     Michael, I dont think there is any issue with fact the Larson was able to do an 86 day crossing of NW passage in 1944, in remarkably ice free conditions (especially compared to his 1940 crossing). What is of issue is that somehow this is evidence that arctic then had less ice than now.
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170. scaddenp at 11:06 AM on 1 July, 2011
     Eric, it also looks like the Argo network may be the most sensitive instrument for climate measure that we have around. Should its measurements fail to show a signal consistent with climate theory in even 5 years would give me serious pause. Would you wait 26 years of warming on that too?
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171. Camburn at 11:10 AM on 1 July, 2011
     Michael: You don't seem to understand what I post, but that is ok. In the eye of the beholder. Scaddenp does, as no where have I asserted that the current ice is more than past ice. However, you might want to check what route the thin skinned vessels used. I believe you will find it is the southern NW passage, which has been low ice for decades. The Canadian Coast Guard makes an annual run in Sept to restock the northern settlements. Has been doing this for decades and decades. With that said, the conditions in the southern passage have become virtually ice free, which in the past was not a normal occurance. The voyage of Capt Larson was extremely remarkable when done, it would still be remarkable today on the path that he took. To give Cryostat full validty I would want to examine it's proxy material for conditions prior to 1979. Just because it is at that site does not give its proxy data credibility.
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172. Camburn at 11:12 AM on 1 July, 2011
     scaddenp: I agree with you that ARGO is an extremely important development. The step jump in OHC is now well known and accepted as a splice problem. The data from ARGO should be much more robust than the XBT etc sets from the past.
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     Response:

     [DB] Time to reel this thread in.  As a reminder, this thread is about Websites for Watching the Arctic Sea Ice Melt.  Other threads exist for the other topics.  Thanks to all for your understanding.
     

173. Camburn at 11:19 AM on 1 July, 2011
     Correction: Not Cryostat.......but Cryosphere today as to validity.
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174. Camburn at 11:19 AM on 1 July, 2011
     thanks for your patience db.
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     Response:

     [DB] As long as discussions are productive, tangential to the thread post and comply with the Comments Policy, the moderators prefer to "let it ride".

175. adelady at 11:42 AM on 1 July, 2011
     Eric "...the North Atlantic is particularly cold this year, and will not provide warm waters to increase melt." But the far North Atlantic is not so congenial. Check out this animation of DMI/COI SST anomalies for June as shown at the Arctic Sea Ice blog mentioned in the post.
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176. michael sweet at 11:50 AM on 1 July, 2011
     Camburn, I posted a response here.
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177. skywatcher at 13:55 PM on 1 July, 2011
     #149 Philippe,, #159 Eric - interesting that 2011 does not show the same sharp decline in June, yet at the end of June, 2011 lies below 2007 on the IJIS graph. Whether it remains so will depend on the melt rate and wind patterns in July. The data for ocean temperatures do not look encouraging for ice retention this year, and when put together with this recent article by Peter Sinclair, it's not encouraging news. #166 Camburn, it's helpful if you want to link to something, especially if it's behind a paywall/a book, that you either summarise the source or provide a quote, or else we have no idea why you have linked to a source, or if the source is relevant at all. As you have not even provided a page reference, let alone any material with which we could evaluate the source (despite repeated requests), I am forced to conclude you don't have much evidence to support your point of view. I can assure you you won't taint my understanding by actually providing information that supports your point!
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     Response:

     [DB] To further your point, comments consisting of links without a demonstration of an understanding of the materiel linked to as well as a sharing of why the information therein is important (GUTFC: give us some context as to why its important) simply beg for deletion.

178. scaddenp at 14:05 PM on 1 July, 2011
     #172 - Camburn, I have responded here
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179. Tom Curtis at 14:38 PM on 1 July, 2011
     Camburn @171, the following map shows the routes took in his two transits of the North West Passage: As you can see, in his east to west passage he took a northerly rout between Victoria Island and Parry Island, before diverting into the strait between Victoria Island and Banks Island. Below is the September sea ice extent in 2010: As you can see, the passage between Victoria Island and Melville Island is entirely clear of ice, as are the waters just north of Banks Island. Ironically, a thin hulled boat could not retrace Larson's route precisely because of ice in the strait between Victoria and Banks Island, but could easily traverse the more northerly rout. Larson traversed these waters during September, exiting Bering Strait on September 27th, so the ice record is directly comparable, and clearly there is much less ice than in 1944. To put that into perspective, the following is the route taken by "Northern Passage" when it circumnavigated the Arctic in a single season in 2010, one of two sail boats to do so: The entire trip took 115 days, and just 26 days to transit the North West Passage. The other boat to complete the trip, the St Peter just beat them for the record of being first to complete the double transit in a single season. (And yes, I did notice that they in fact took the southern rout, I assume out of caution. But the ice would have permitted the northern passage.)
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180. Camburn at 14:56 PM on 1 July, 2011
     Thank you Tom. I have tried posting pictures, but have not had success at that yet. I do not dispute that there is less ice now than in 1944. What I was trying, and apparantly failing to present, was that in 1944 the ice extent had to be substantially less than say 10 years later. And for the St Roch to make the passage in 1944 was a feat unto itself. I read the link to Tamino's post. I have a couple of problems with how the data for ice conditions in the past was assembled, but nothing that would change the overall trend. Thank you again for posting the above.
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181. Dikran Marsupial at 18:19 PM on 1 July, 2011
     Camburn wrote: "One of the main reasons for this is the sine components within the measured and proxy temp record." Human beings are very good at detecting patterns where no pattern exists. Just because there appears to be a cyclical pattern in the data, doesn't mean that it is indicatve of some underlying physical process. This is especially true where the quantity of interest is affected by a number of different independent processes. In this case, temperature is affected by solar forcing, CO2 radiative forcing, aerosol cooling, ... and on top of that you have the effects of the various feedbacks. So if there is an apparent cycle, how can you tell whether there really is some underlying cyclical physical process. Just looking at the data can't tell you that; statistics can't tell you that (correlation is not causation); what you need is physics. Climatologists call this sort of work an "attribution study", for instance the IPCC attribute the warming of the first half of the 20th century to solar forcing, aerosol cooling cusing a levelling of of temperatures mid-century and CO2 radiative forcing dominant from 1970 or so. These three independent events give the appearance of a centenial scale cycle, but that is entirely spurious. As a statistician, I know that physics trumps stats, so I go with the climatologists who have explanations of why the climate record looks like it does, rather than statisticians/eye-ballers who attribute the climate record to unexplained "climate cycles".
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182. Eric the Red at 22:53 PM on 1 July, 2011
     Dikran, While your summary is plausible based on the data, Camburn's theory is also plausible based on the same data. It could just be coincidence that the two previous warming cycles aligned in both magnitude and duration, while the cooling cylces align in duration, but differ slightly in magnitidue. Both theories are on based on physics, but are using different principles. The physics in Canburn's sine component tells us that temperatures should decline in the next decade or two, while in Dikran's explanation, temperatures should resume a large warming trend. That is where the data enters. The data will tell us whether the temperature changes were cyclic or spurious. As a fellow statistician, I can say that three cycles (if they were to occur) have a large improbability of being due to chance alone.
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     Response:

     [DB] To further Dikran's point, a focus on mystical cycles without a grounding in the physical principles underlying and explaining the cycles is termed mathturbation.  It is the statistical version of saying "I see Dead People", and little removed from poking at chicken entrails with a stick.

     This post is on Websites for Watching the Arctic Sea Ice Melt.  Other threads here at SkS deal with cycles and such can be located via the Search function.

183. michael sweet at 23:23 PM on 1 July, 2011
     A brief recap of June for those who do not follow sea ice: IJIS Graph for June 30, 2011 2011 ran neck and neck with 2010 for the lowest amount of sea ice for the entire month of June. The last two days of June 2011 fell off a little so 2010 is ahead. 2007 started its amazing two week drop at the end of June. Everyone expects 2007 to be in lowest place in a few days. 2010 fades a little in July. The weather in July will determine which year is lowest at the end of July. Even WUWT has stopped claiming that the ice is recovering this year. Where will 2011 end up?? Place your bets. The NSIDC monthly report should be out by next Friday. They always have insightful reporting. Hopefully it will be a long summary. Antarctic sea ice is running slightly below average.
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184. skywatcher at 23:24 PM on 1 July, 2011
     #182 Eric: What physics was in Camburn's statement? The, ah, physics of the sine wave? I prefer the physics that tells us about the absorbtion of infrared radiation by particular kinds of small molecules, like CO2 and CH4. Pattern matching tells us nothing about the underlying processes. On one hand here, we have a good pattern match (using solar, GHG, aerosol and volcanic forcing) that is underpinned by sound physics, of the kind that allows mobile phones, microwave ovens and CO2 lasers to work, and is verified by a large amount of observation. On the other hand, we have an apparent pattern less than two cycles long with no predictive power whatsoever. People see patterns and sine waves everywhere but, without a sound physical basis, they're garbage.
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185. les at 23:29 PM on 1 July, 2011
     184 skywatcher - Tamino has a good phrase for that, as used in his recent chaos thread.
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186. Dikran Marsupial at 23:31 PM on 1 July, 2011
     Eric@182 "sine components" is not a theory. There is no physical explanation of why there should be a sine component, just a suggestion that one exists (which could be used to make a prediction). History tells us that when predictions are made that are not based on physics, all that happens when the data refute the prediction is that the prediction is altered (e.g. epicycles in Ptolmaic astronomy) until it fits again. In this case, all that will happen when the data refutes the current view of cycles is that some new natural cycle will be introduced acting on a longer time scale to "explain" the discrepancy. If you want an example of that, just look at the "no warming since 1998, no err 2002" canard. Skeptics were claiming that the lack of warming since 1998 was the start of the cooling trend. When it was clear that wasn't happening, they just shifted the start point and made the same claims all over again. Those of us who look at the physics understood why the claim was bogus in the first place. I would venture to suggest that like many statisticians you are paying too much time to the data and too little to the data generating process (the whole point of statistics is to learn about the data generating process). If there is a plausible physical model for the last cycle and a half, it is bogus to claim that there is three cycles and hence a low probability that it ocurred by chance alone (nobody is claiming it was chance alone BTW, but due to physics). However, if you want to give a formal statistical analysis of the cycles, then go ahead, I for one would be interested in discussing it (although this is probably not the right thread).
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187. Eric the Red at 00:14 AM on 2 July, 2011
     michael, Sounds like a fun bet. I believe that the 2007 record is safe for another year. All the other years cluster together near the end of July before separation during September. A stronger than average melt could bring 2011 to 2nd lowest, but a weaker melt could land it at 6th. Therefore, I will bet on 4th lowest coming in somewhere between 2009 and 2010.
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188. Riccardo at 00:59 AM on 2 July, 2011
     Dikran Marsupial no doubt that just two purported cycles do not make a real pattern, more so when an arbitrary underlying trend is added. We've already seen this a while ago. No physics no party, I'd say as a physicist ;)
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     Moderator Response: [Dikran Marsupial] Absolutely, statistics can be very helpful in trying to identify the data generating process, but at the end of the day, the data generating process is what we want to understand, rather than the data. For that you need physics.
189. Philippe Chantreau at 02:36 AM on 2 July, 2011
     Eric, Warm waters are not nearly as much of a factor for determining the minumum extent as weather patterns. The extent drops when ice is fragmented and exported South. Winds and currents do that.
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190. Camburn at 03:11 AM on 2 July, 2011
     Probably the largest change in the Arctic in the past 15 years has been the amount of black carbon intertwined in the ice as a result of China's dramatic increase in coal powered power plants with what looks like no pollution controls in place. See the Shinell link I have posted. The increase in albedo means ice melting in place, or becoming so weak that it fragments very easily. As the Catlin expidition noted, the dynamics of melting ice in place changes the dynamics of water temperature as well.
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191. Bob Lacatena at 10:31 AM on 9 July, 2011
     Has anyone else noticed the huge meltpool that's recently developed seemingly right under north pole cam 2?
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192. Albatross at 10:40 AM on 9 July, 2011
     Sphaerica @191, Good grief! I wonder if its proximity tot he lead has anything to do with that? The researcher must be nervous about losing their equipment... 2011 is now tracking below 2007, the next few weeks will be telling. If I am looking at the ECMWF data correctly, the Arctic dipole is expected to set up. Other guidance is suggesting above average temperatures and sunshine over much of the Arctic basin in the next week or so. All this does not bode well for the beleaguered Arctic sea ice...
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193. Daniel Bailey at 23:44 PM on 9 July, 2011
     Meltcam #1 seems to have passed perihelion and is already heading towards The Door of Night:
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194. Bob Lacatena at 01:41 AM on 10 July, 2011
     193, DB, I'm very surprised this would happen. I've always assumed that the melt pools are shallow and just near the surface. This implies deeper melting than that. By the way, have you ever seen the photos of the U.S. submarines that surfaced at the North Pole in the fifties and sixties? This has been a common denier tool to claim the pole has melted like this before (hah!). I've never seen an explanation of that, but I've always suspected that what looks like open water is in fact just shallow melt pools on the surface, with ice underneath that is much thicker (as well as being a rare thin area that was specifically located to be able to surface). Does anyone know the facts, or know how to find out?
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     Moderator Response: (DB) There's a recent paper out quantifying the increased transmission of the sun's energy through melt pools; Patrick Lockerby did a takedown of the NP submarine denier meme on his blog some time back. Not at a PC for a while but I'll put up the links when I can.
195. Camburn at 02:35 AM on 10 July, 2011
     The subs use sonar to look for leads in the ice. Any ice greater than 1 meter results in structural damage if they tried to surface. There is always thin ice at the poles because of the currents. The melt pools/leads shown in the photograph are a normal occurance, even in May.
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     Moderator Response: (DB) Please substantiate your claim about thin ice always being found at the pole with a link to a credible source; I have personally seen sub logs that belie your claim.
196. michael sweet at 03:37 AM on 10 July, 2011
     Sphaerica, If you look beyond the pools you will see wide leads in the ice. These have been visible for several weeks and vary in width day to day. A sub could come up in one of the leads. Camburn: If you read the background information on the web cam page you will find out that: "In 2010, the snow became soft Jun 25, similar to many other years, but widespread meltponds formed by Jun 27, earlier than in any of the other years observed by the webcams." This year melt ponds formed earlier than in 2010 (at the end of June), although they refroze for a few days. Your claim of pond formation in May is incorrect. Please try to be more accurate in the future. According to the Barrow Sea Ice Oservatory (linked through Neven's web site), melt ponds have been observed at Barrow at the end of May. Perhaps you are confusing Barrow with the North Pole.
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197. Bob Lacatena at 03:56 AM on 10 July, 2011
     194, DB (inline), I did find this link: Nonsense On Ice. Is that the one you're talking about?
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     Moderator Response: [DB] Yes. See also JMurphy's comment below.
198. JMurphy at 04:24 AM on 10 July, 2011
     That first USS Skate photo has also been discussed at Arctic Sea-Ice Blog - Patrick Lockerby joins in there too. In fact, Neven (whose site it is) uses the picture as his avatar. Basically, it has been used by so-called skeptics, to claim that the Arctic has been ice-free lots of times in the past. I first saw it used on WUWT (no surprise there) but some of the comments on WUWT (from real sceptics, of course) about the photo show that it cannot be proven to be at the place and time often suggested, i.e. March 17, 1959. Patrick Lockerby shows that also. In fact, there is no official original for that photo - the link at NavSource.org (where the copy is held) goes to a web-hosting service called Tripod.com.
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     Response:

     [DB] Also correct.  The discussion begins in that thread here.

199. CBDunkerson at 05:23 AM on 10 July, 2011
     In any case, the 'Nonsense On Ice' link Sphaerica provided in #197 above includes several photos showing the Skate having broken through the ice, people standing on the ice next to the sub, et cetera... all on exactly the same date (March 17, 1959) when it was supposedly in 'open water' at the North Pole.
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200. Daniel Bailey at 14:48 PM on 10 July, 2011
     Here's that paper on ponded ice: From Itoh et al 2011:

     "Sea-ice melting processes were inferred from in situ sea-ice and ocean condition data obtained in the Arctic in summer 2006 and 2007. The relationship between ice concentration observed by on-board ice watches and water temperature showed negative correlations. This implies that as ice concentration decreases, the upper ocean becomes warmer due to greater absorption of solar radiation into open water, which promotes ice melting. However, heating of surface water is significant even in regions that were almost completely ice-covered, suggesting that transmitted solar radiation through the ice is also effective at melting sea ice. A simplified ice–upper-ocean coupled model was applied to examine the effect of heat input from open water, thick ice and thin ice. The ponded thin ice is estimated to transmit approximately three times more solar radiation than ponded thick ice. Model results suggest that transmission of solar radiation through ponded ice amplified the ice-albedo feedback mechanism, particularly in thin ice regions. Recently, the extent of old and thick multi-year ice in the Arctic Ocean has been rapidly reduced. As a result, heat input to the upper ocean through the ice is enhanced and ice melt is further accelerated."

     Emphasis added.
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