ORH_wxman

2016 looks like it had a lot more easy pickings after 8/10 for losses than this year. If parry stait melts out then that could add some to 2019 but 2016 looked easier:

Why do we think 2019 will act more like 2016 than 2012 after August 10th?

We've fallen 350k behind 2012 on area despite extent still being very close. We're probably going to need a big compaction pattern to keep extent in the running through the end of this month.

2017 was decently snowy...though not excessive. But we haven't had a snowy Niño December since 2009. Were kind of due for one even though they are typically not favored. We've gone 3 horrendous Niño Decembers in a row since '09....maybe the excessive blocking we've seen recently will be able to manifest itself early this winter. That's typically a requirement for a snowy Niño December. In La Niña, we often can get away with less blocking in December. Not in El Niño. Of course, it could be warm neutral too. We'd be less reliant on blocking if it was but we'd still want to see it.

Seems like we're favorites for either warm-neutral or weak Niño. Obviously things can change but the subsurface doesn't look overly impressive and the model forecasts seem to agree.

2012 has expanded it's area lead to 210k....the best chance for 2019 is if the Laptev can retreat further than 2012. That's the weak spot when comparing year over year.

Extent definitely has a better chance to beating 2012 than area. We're 170K behind in area now and 2012 doesn't slow down any time soon. We'll need some breathtaking losses to keep pace. If we have enough compression of the pack though, extent could still challenge even if area does not.

On extent or area? I think 2007 both extent and area are very good chances to be surpassed by 2019...2016 has a good chance on extent but not as good for area. Prob like a 50/50 chance or less to pass 2016 area.

I agree with the low chance of beating 2012 at this point. I wanted to see a pretty good sized lead heading into late July/early August. I might go higher than 3% on extent but not by a lot. Maybe 10-20%. For area I probably wouldn't go higher though as we slightly trail 2012 in area.

I mentioned before that Atlantic and CAA may prevent us from getting a new record. Much more ice there this year than 2012. But we still have a chance if ESS/Laptev can melt back far enough. We're tied for area right now. 2012 has some epic losses in early August though which is why I'm still a bit skeptical in addition to just looking at the individual regional concentration maps.

Still a chance, but pretty low odds IMHO. We'll need some very warm August weather. Atlantic and CAA are a problem further out in time. We'll need the ESS/Laptev sectors to melt toward the pole further than 2012 did to have a chance because the ATL and CAA are going to finish higher than 2012.

Yes, most likely....we've already seen some slowing the last few days. I'm not sure this year will be able to keep pace with 2012 going forward with that pattern. But we'll see.

Here's an animation comparing 2019 to 2012 on this date. I think the key to getting a new record is clearly going to be the Laptev/ESS side of the ice. The CAA are Atlantic side of the CAB are running way behind 2012 and those are going to be problems in sustaining the big losses. Click to animate....

I don't hope for catastrophic warming. But a record low extent makes it a more interesting season to track. I don't think there is some massive catastrophe that happens either if we break a record min. It didn't happen in 2012. We actually ended up rebounding in a big way the following season. Anyways, 2019 is off to a strong start in July so if we can build a couple hundred thousand lead on 2012, then we may have a chance. 2012's losses are so breathtaking later in the month and early August that we'll need to build up some more momentum. June didn't quite do the trick but if early July is hostile enough, maybe it can make up for it.

He's not wrong that there were probably some pretty low ice extents in the late 1930s or 1940s akin to perhaps the late 1990s or early 2000s but that definitely doesn't matter in the larger picture. The best data starts in 1979 so that is the natural starting point for most ice related graphs. It's not some conspiracy.

Final June NSIDC-adjusted area numbers are in, and we're currently 2nd lowest on record behind 2012 though 2007 and 2010 were very close to 2019 as well. What this means is that this year has an excellent chance to finish in the top 3 lowest extent/areas on record. Here are the top 5 lowest: 2012 (6.53 million sq km) 2019 (6.76 million) 2010 (6.77 million) 2007 (6.81 million) 2016 (6.94 million) Does this year have enough of a good start to set a new record? Most likely not. The numbers do not support it. That doesn't mean 0 chance though like more recent years. But we will have to set a new record for area loss between now and the minimum to get there...however, we don't have to set it by much....only about 40k. If we melt 40k more area than 2016 from here on out, we'll set a new minimum area record. The average 2007-2018 loss from July 1st onward was 4.13 million sq km. That would leave 2019 at 2.63 million sq km of ice at the minimum for area. The 2012 record sits at 2.22 million sq km of ice which means in order to set a new recrod, we need to lose 4.56 million sq km of ice area. 2016 is the current record of ice area loss from this point forward losing 4.52 million sq km. So as stated above, we will need to beat this by about 40k or more to pass 2012 at the minimum. That is going to be about 2 standard deviations or even a little more for losses. So I'd put the chances of setting a new record at about 5%. Again, this is for area only. Not extent. Extent is a little tougher since things like compaction can occur that affect extent a lot more than it affects area. Still, it will be hard to set the extent record as well. We might have a slightly greater than 5% chance at setting the extent record since 2012 wasn't extremely compacted. Getting back to area, below is a histogram of what would happen to 2019 if we followed all area losses from previous years....so for example, if we followed 2018 area losses from this point forward, we would finish with an area minimum of just over 2.50 million sqkm: So given the information above, I am going to predict a minimum area of 2.60 million sq km +/- 200k (2.4-2.8 for a range). I will set a minimum NSIDC extent of 3.8 million sq km +/- 200k (3.6-4.0 as a range). Neither of these ranges include the 2012 record...I don't believe we will quite make it. But this year at least has an outside shot unlike previous recent years, so at least there is a reason to track closely.

2010 (not listed on the graph) was actually the leader right now....but then it stalled starting tomorrow. But I think this year def has a better chance than 2010 since the weather forecast remains favorable for big ice losses over the next week.

I think "ice-free" has been defined as less than a million sq km of ice extent. I'm not sure if blue ocean event is the same thing but I'd assume it is. 100% ice free will never happen in this century because there will always be some residual ice clinging to northern Greenland or chunks of ice breaking off the Greenland glaciers.

The chance of a blue ocean event this year is 0%.

2019 is still in the running, but will need a strong finish to June: 2016: +70k 2012: -190k 2010: -300k 2007: +5k You can see how 2010 was actually running ahead of 2012 here for melting, but it then stalled near the end of the month and it continued into early July....putting an end to any chance of a nuclear finish like 2012 had. The guidance this year has a very impressive dipole to finish the month of June...so we might have a legit shot here. The big question will be if we can turn that into a big blocking high over the CAB or if it retreats more to the Asian side and becomes a reverse dipole, which would probably put an end to our chances at a record....the guidance is kind of split on that idea for the longer term. This melt season might finally have some drama after the colder early summers we've seen in recent years.

Area already takes into account lower concentration. So if the pack is very fragmented, we will get lower area readings. I don't see any clear evidence why we should treat area as different than we normally do. This year is already quite low on area, so it isn't like area is showing something drastically different than what we'd expect given the very warm conditions thus far. If we get very hostile weather from here on out, we could still see a new record low this year. Right now, I'd bet against it, and settle on something in the top 3 or 4 instead. But there is still time for things to change.

The thing is....NSIDC area is measured by SSMI/S and that particular satellite gets "tricked" by melt ponds into thinking it is water. It's been measuring like this for decades so we have a consistent database. So if we are a few hundred thousand sq km behind 2012 on this measurement, it's likely because we have less melt ponding than that year. Since melt ponding in June is the best predictor of final extent/area, we closely monitor the SSMI/S area numbers.

Area is basically in a dead heat with 2016 right now. We'll see if it can pull ahead before the end of the month. Extent is harder to predict. It's a lot easier to predict final area. Extent obviously has the nuances of compaction...take 2015 vs 2010 for example. 2015 finished with greater area but far less extent since 2015 had an epic compaction occur in August/early September. That's probably why they missed the extent prediction the most of any of their forecasts. They correctly saw that there would likely be more ice area than some other years at the minimum but had no way of knowing how compacted it would be.

This is in line with area numbers...which is a proxy for melt ponds.

Here's the current breakdown of how other years compare to 2019 right now......i.e, 2018 had 370k sq km more ice than 2019 at this point. 2018: +370k 2017: +300k 2016: -20k 2015: +170k 2014: +390k 2013: +350k 2012: -280k 2011: +70k 2010: +50k 2009: +1.1 million 2008: +450k 2007: -20k What sticks out here is how closely bunched 2019 is with 2016, 2011, 2010, and 2007 (and how much more ice 2009 had at this point than the others). Those are big melt years, so this one is on track for a big year. But we're still clearly lagging 2012 and that gap probably will need to be closed significantly before the end of the month to have a chance at a new record. 2012 loses about 1.2 million sq km of area between now and 6/30, so we're gonna need to lose more than that....which is hard to do. Only 2010 and 2007 lost more between 6/19 and the end of the month than 2012 did. The pattern beyond D6-7 on the euro shows a very hostile setup for the ice....I think we'll need this to verify in order to keep within striking distance of 2012.