bluewave Posted November 1, 2019 Share Posted November 1, 2019 According to the NSIDC data, October 2019 beat 2012 for the lowest monthly average extent. This makes the 3rd new lowest monthly extent record for 2019. It’s also the 10th new lowest monthly extent since 2016. ftp://sidads.colorado.edu/DATASETS/NOAA/G02135/seaice_analysis/Sea_Ice_Index_Monthly_Data_with_Statistics_G02135_v3.0.xlsx 1 2019 5.66 2 2012 5.89 NSIDC lowest average monthly extents Jan...2018 Feb...2018 Mar...2017 Apr....2019 May...2016 Jun....2016 Jul.....2019 Aug...2012 Sep...2012 Oct...2019 Nov...2016 Dec...2016 2 Link to comment Share on other sites More sharing options...
csnavywx Posted November 2, 2019 Share Posted November 2, 2019 Should have a few more days of big gains from the remnant open water area in the Laptev, then a marked slowing as the Pacific side OHC remains high and the weather pattern turns hostile for growth. 1 Link to comment Share on other sites More sharing options...
bluewave Posted November 2, 2019 Share Posted November 2, 2019 9 hours ago, csnavywx said: Should have a few more days of big gains from the remnant open water area in the Laptev, then a marked slowing as the Pacific side OHC remains high and the weather pattern turns hostile for growth. Similar to the findings in this recent paper. https://advances.sciencemag.org/content/4/8/eaat6773 DISCUSSION Implications and outlook The doubling of BG halocline heat content over the past three decades appears attributable to a warming of the source waters that ventilate the layer, where this warming is due to sea ice losses in the Chukchi Sea that leave the surface ocean more exposed to incoming solar radiation in summer. The effects of an efficient local ice-albedo feedback are thus not confined to the surface ocean/sea ice heat budget but, in addition, lead to increased heat accumulation in the ocean interior that has consequences far beyond the summer season. Strong stratification and weak mechanical mixing in the BG halocline ensure that significant summertime heat remains in the halocline through the winter. With continued sea ice losses in the Chukchi Sea, additional heat may continue to be archived in the warm halocline. This underscores the far-reaching implications of changes to the dynamical ice-ocean system in the Chukchi Sea region. However, there is a limit to this: Once the source waters for the halocline become warm enough that their buoyancy is affected, ventilation can be shut off. Efficient summertime subduction relies on the lateral surface front in the NCS region between warm, salty water that is denser to the south and cooler, fresher water that is less dense to the north. For longer-duration solar warming (that is, longer-duration ice-free conditions in the region), SSTs on the south side of the front may become warm enough (around 13°C, under the assumption of a 1.5-month ice-free period dominated by solar absorption) that the lateral density gradient is eliminated [see (24)]. It remains to be seen how continued sea ice losses will fundamentally change the water column structure and dynamics of the Arctic halocline. In the coming years, however, excess BG halocline heat will give rise to enhanced upward heat fluxes year-round, creating compound effects on the system by slowing winter sea ice growth. 2 Link to comment Share on other sites More sharing options...
Typhoon Tip Posted November 3, 2019 Share Posted November 3, 2019 23 hours ago, bluewave said: Similar to the findings in this recent paper. https://advances.sciencemag.org/content/4/8/eaat6773 DISCUSSION Implications and outlook The doubling of BG halocline heat content over the past three decades appears attributable to a warming of the source waters that ventilate the layer, where this warming is due to sea ice losses in the Chukchi Sea that leave the surface ocean more exposed to incoming solar radiation in summer. The effects of an efficient local ice-albedo feedback are thus not confined to the surface ocean/sea ice heat budget but, in addition, lead to increased heat accumulation in the ocean interior that has consequences far beyond the summer season. Strong stratification and weak mechanical mixing in the BG halocline ensure that significant summertime heat remains in the halocline through the winter. With continued sea ice losses in the Chukchi Sea, additional heat may continue to be archived in the warm halocline. This underscores the far-reaching implications of changes to the dynamical ice-ocean system in the Chukchi Sea region. However, there is a limit to this: Once the source waters for the halocline become warm enough that their buoyancy is affected, ventilation can be shut off. Efficient summertime subduction relies on the lateral surface front in the NCS region between warm, salty water that is denser to the south and cooler, fresher water that is less dense to the north. For longer-duration solar warming (that is, longer-duration ice-free conditions in the region), SSTs on the south side of the front may become warm enough (around 13°C, under the assumption of a 1.5-month ice-free period dominated by solar absorption) that the lateral density gradient is eliminated [see (24)]. It remains to be seen how continued sea ice losses will fundamentally change the water column structure and dynamics of the Arctic halocline. In the coming years, however, excess BG halocline heat will give rise to enhanced upward heat fluxes year-round, creating compound effects on the system by slowing winter sea ice growth. Yeah, I believe you and I discussed this a bit over a month ago regarding the "thermal residence/memory" - this year seemed to smack of some of that if you recall, in that there was a late 'time-relative' occurrence of the 2019 numbers slipping lower than 2012 post the annual nadir. It's always nice when we see other sources corroborating our own observations. 2 Link to comment Share on other sites More sharing options...
Typhoon Tip Posted November 6, 2019 Share Posted November 6, 2019 Fwiw - https://climate.nasa.gov/news/2913/2019-arctic-sea-ice-minimum-tied-for-second-lowest-on-record/ 1 Link to comment Share on other sites More sharing options...
bluewave Posted November 6, 2019 Share Posted November 6, 2019 Every month since April has featured top 3 warmth in the Arctic. This is a first for April through October. https://www.esrl.noaa.gov/psd/data/timeseries/ 3 Link to comment Share on other sites More sharing options...
Typhoon Tip Posted November 12, 2019 Share Posted November 12, 2019 https://phys.org/news/2019-11-arctic-ice-refuge.html 1 Link to comment Share on other sites More sharing options...
Typhoon Tip Posted November 15, 2019 Share Posted November 15, 2019 https://phys.org/news/2019-11-arctic-ocean-ice-free-year.html 2 Link to comment Share on other sites More sharing options...
banshee8 Posted November 20, 2019 Share Posted November 20, 2019 On 11/15/2019 at 6:09 AM, Typhoon Tip said: https://phys.org/news/2019-11-arctic-ocean-ice-free-year.html Keeps getting pushed back... https://nsidc.org/news/inthenews/arctic-could-be-ice-free-2020-scientists-say https://nsidc.org/news/inthenews/arctic-could-be-free-summer-sea-ice-2030 Link to comment Share on other sites More sharing options...
bdgwx Posted November 20, 2019 Share Posted November 20, 2019 44 minutes ago, banshee8 said: Keeps getting pushed back... https://nsidc.org/news/inthenews/arctic-could-be-ice-free-2020-scientists-say https://nsidc.org/news/inthenews/arctic-could-be-free-summer-sea-ice-2030 Broadly speaking the first "ice-free" year has been getting pushed up. You'll find select studies here and there that have really aggressive predictions, but those are either few in number or not well received enough to influence the consensus much. In the 1990's the prevailing prediction was around 2100 or thereafter. And in the IPCC's AR3 report from 2001 it was stated (via a chart) that the first annual mean extent of 10.5e6 km^2 would not occur until about 2040. In reality it actually occurred in 2007. Even today many sea-ice models continue to struggle with the rapid pace of sea ice declines in both the NH and SH. Today it seems as though the consensus lands somewhere in the 2040-2060 range. So we still have a good wait ahead of us before we see < 1e6 km^2 of extent at the minimum. It's certainly possible that it could occur prior to 2040. Some on this forum and the ASIF believe we'll be lucky to make it to 2040. I'm in the more conservative camp and believe it will be after 2040. I'm prepared to be proven wrong though. 1 Link to comment Share on other sites More sharing options...
banshee8 Posted November 20, 2019 Share Posted November 20, 2019 2 hours ago, bdgwx said: Broadly speaking the first "ice-free" year has been getting pushed up. You'll find select studies here and there that have really aggressive predictions, but those are either few in number or not well received enough to influence the consensus much. In the 1990's the prevailing prediction was around 2100 or thereafter. And in the IPCC's AR3 report from 2001 it was stated (via a chart) that the first annual mean extent of 10.5e6 km^2 would not occur until about 2040. In reality it actually occurred in 2007. Even today many sea-ice models continue to struggle with the rapid pace of sea ice declines in both the NH and SH. Today it seems as though the consensus lands somewhere in the 2040-2060 range. So we still have a good wait ahead of us before we see < 1e6 km^2 of extent at the minimum. It's certainly possible that it could occur prior to 2040. Some on this forum and the ASIF believe we'll be lucky to make it to 2040. I'm in the more conservative camp and believe it will be after 2040. I'm prepared to be proven wrong though. I mean, the NSIDC is a pretty mainstream source. I think some predictions got a lot more aggressive after 2007, but most toned it down after about 2013. Link to comment Share on other sites More sharing options...
bdgwx Posted November 20, 2019 Share Posted November 20, 2019 45 minutes ago, banshee8 said: I mean, the NSIDC is a pretty mainstream source. I think some predictions got a lot more aggressive after 2007, but most toned it down after about 2013. NSIDC isn't the source though. Their "NSIDC in the News" section is just links to various articles and blogs that mention NSIDC. They have hundreds of links in this section every year. It's not even clear if these articles (which are dead links now) were in reference to a bona-fide peer reviewed study or some random blogger's opinion. Note the disclaimer in the section. The following items link to media coverage of NSIDC in various news outlets, online magazines, editorial pieces, and blogs. The content of these articles and blog posts does not necessarily reflect the views of NSIDC, our collaborators, or our funding agencies. Like I said, I can't see the articles anymore so I have no idea what the details of these "predictions" are. But based on the timing of when the articles appear I can speculate a bit. There were two fellows during this period that made some very aggressive predictions that got widespread media attention. The first was Maslowski and the second was Wadhams. Neither was characterized by broad acceptance in the academic community. In Wadham's case he was pretty much entirely ignored. Maslowski was a legit researcher but in his defense his work was frequently taken out of context. His 2016±3 date (which was often erroneously cited as 2013) was statistical and appeared in a publication that I believe used many methods to arrive at many different estimates with 2016 being the lowest therefore making a cherry pick and really bad at that. Masklowski even warned against taking his work out of context and specifically chided Al Gore for doing just that. The point...be careful about linking media popularity with the mainstream views of bona-fide scientists. They are often at odds with each other. 1 Link to comment Share on other sites More sharing options...
Fantom X Posted November 21, 2019 Share Posted November 21, 2019 Latest extent. 2 Link to comment Share on other sites More sharing options...
lookingnorth Posted December 5, 2019 Share Posted December 5, 2019 The 5-day mean is still in third place for lowest extent, but it's near a lot of other years. 1 Link to comment Share on other sites More sharing options...
bluewave Posted December 5, 2019 Share Posted December 5, 2019 The record amount of open water for the Chukchi Sea continues to be one of the big stories this year. 2 Link to comment Share on other sites More sharing options...
donsutherland1 Posted December 8, 2019 Share Posted December 8, 2019 On 12/5/2019 at 3:04 PM, bluewave said: The record amount of open water for the Chukchi Sea continues to be one of the big stories this year. Utqiagvik is easily on course for its warmest year on record. It is all but improbable that the record will fall. Further, that city will likely finish with its first annual mean temperature of 20.0 degrees or above. 2 Link to comment Share on other sites More sharing options...
WarmNose Posted December 20, 2019 Share Posted December 20, 2019 Curious to see where this leads. Looks like a major arctic ice addition is in the cards for the end of the year. Healthy PV Link to comment Share on other sites More sharing options...
nycwinter Posted December 20, 2019 Share Posted December 20, 2019 funny how many talk about sea ice extent loss only in the summer and early fall, but not the sea ice gains in winter.. hmm... 1 1 Link to comment Share on other sites More sharing options...
LibertyBell Posted December 21, 2019 Share Posted December 21, 2019 18 hours ago, nycwinter said: funny how many talk about sea ice extent loss only in the summer and early fall, but not the sea ice gains in winter.. hmm... it's all about net.... if the losses in the summer outnumber the gains in the winter year after year it wont matter. You're seeing the effects of that now with parts of the Keys going permanently under water. The King Tide came in a few months ago and never left. 1 Link to comment Share on other sites More sharing options...
donsutherland1 Posted December 22, 2019 Share Posted December 22, 2019 On 12/20/2019 at 1:11 PM, nycwinter said: funny how many talk about sea ice extent loss only in the summer and early fall, but not the sea ice gains in winter.. hmm... Young ice melts fairly fast. It's the ice melt over the summer that has a large influence over how much of the incoming solar radiation is reflected and how much is not. Declining summer sea ice is playing a large role in Arctic amplification (as it is a feedback that amplifies the ongoing warming already underway). That's a major reason why Arctic warming has exceeded the rate of global warming, especially in recent decades. Link to comment Share on other sites More sharing options...
donsutherland1 Posted December 22, 2019 Share Posted December 22, 2019 12 hours ago, LibertyBell said: it's all about net.... if the losses in the summer outnumber the gains in the winter year after year it wont matter. You're seeing the effects of that now with parts of the Keys going permanently under water. The King Tide came in a few months ago and never left. Sea ice melt doesn't raise the sea level by itself. It does make an indirect contribution as a feedback mechanism that is accelerating Arctic warming. That warming affects the Greenland ice sheet. Greenland's melt, which has accelerated greatly over the past few decades, has been a key driver in rising sea levels. 2 Link to comment Share on other sites More sharing options...
LibertyBell Posted December 22, 2019 Share Posted December 22, 2019 7 hours ago, donsutherland1 said: Sea ice melt doesn't raise the sea level by itself. It does make an indirect contribution as a feedback mechanism that is accelerating Arctic warming. That warming affects the Greenland ice sheet. Greenland's melt, which has accelerated greatly over the past few decades, has been a key driver in rising sea levels. we'll have a huge problem if the entire ice sheet up there melts. Don did you see the new projections for NJ of 1 ft sea level rise by 2030 (over 2000 levels) and a 6 ft rise over those levels by 2100? Link to comment Share on other sites More sharing options...
donsutherland1 Posted December 22, 2019 Share Posted December 22, 2019 4 hours ago, LibertyBell said: we'll have a huge problem if the entire ice sheet up there melts. Don did you see the new projections for NJ of 1 ft sea level rise by 2030 (over 2000 levels) and a 6 ft rise over those levels by 2100? It won't melt immediately and could take centuries to do so. Nevertheless, it appears that humanity is committing itself to a course that could lead to that outcome given little or no response to the need to reduce greenhouse gas emissions (projected to have increased another 0.6% this year). The latest Arctic Report Card provides a glimpse of what is currently happening in the Arctic. https://www.arctic.noaa.gov/Portals/7/ArcticReportCard/Documents/ArcticReportCard_full_report2019.pdf 1 Link to comment Share on other sites More sharing options...
WarmNose Posted December 24, 2019 Share Posted December 24, 2019 Yowzer! The return of the Arctic. What a vortex this is forecasted to be Link to comment Share on other sites More sharing options...
WarmNose Posted December 25, 2019 Share Posted December 25, 2019 Oof. And it’s just getting started Link to comment Share on other sites More sharing options...
bdgwx Posted December 25, 2019 Share Posted December 25, 2019 According to the NSIDC the 5 day average is well outside the interdecile range and just barely inside the 2σ envelope. It is 870,000 sq km below the 1981-2010 mean. Also, I counted 6 other times in which sea ice extent increase from 12/1 to 12/23 was higher. Link to comment Share on other sites More sharing options...
psv88 Posted December 26, 2019 Share Posted December 26, 2019 20 hours ago, WarmNose said: Oof. And it’s just getting started Nope 1 1 Link to comment Share on other sites More sharing options...
donsutherland1 Posted December 26, 2019 Share Posted December 26, 2019 17 hours ago, psv88 said: Nope One shouldn't be surprised that Heller, who has no scientific background, would imply that the winter freeze suggests a healthy Arctic sea ice situation. The difference between the 12/23 extent and minimum extent is largely the result of a very low minimum figure. According to Heller's logic, 2012 would have been seen as a fantastic year, as sea ice extent increased by nearly 8.7 million square kilometers by December 23. Of course, 2012 saw a record low minimum extent figure of just under 3.2 million square kilometers. In fact, the 12/1-23 average of 11.144 million square kilometers is the 3rd lowest on record and is nearly 3% below the 2000-19 average. This is not a healthy Arctic sea ice situation. If multi-year "old" ice were increasing, that would be newsworthy. The annual refreeze in 2019 is not. 3 Link to comment Share on other sites More sharing options...
BillT Posted December 26, 2019 Share Posted December 26, 2019 multi year old ice IS increasing.......https://stevengoddard.wordpress.com/2015/02/18/huge-increase-in-oldthick-arctic-sea-ice/ 1 1 Link to comment Share on other sites More sharing options...
psv88 Posted December 26, 2019 Share Posted December 26, 2019 1 hour ago, BillT said: multi year old ice IS increasing.......https://stevengoddard.wordpress.com/2015/02/18/huge-increase-in-oldthick-arctic-sea-ice/ Article is 5 years old 3 Link to comment Share on other sites More sharing options...
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