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Messages - grixm

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1
Arctic sea ice / Re: The 2019 melting season
« on: August 21, 2019, 09:30:09 AM »
PIOMAS data is out, see separate thread.

Melt momentum still looks strong and we're barely behind 2012 even post-GAC. A record low may still be possible depending on weather

2
Arctic sea ice / Re: The 2019 melting season
« on: August 17, 2019, 09:18:26 AM »

3
Arctic sea ice / Re: The 2019 melting season
« on: August 17, 2019, 07:59:50 AM »
It looks, very tentatively, like "normal" flow (clockwise, leading to south export) is trying to reassert itself in the PGAS, but I'm not going to make any definitive proclamations on one day of satellite images.

On the other hand, I will make proclamations about Massey Sound, which is just a brutal place for the ice to die right now.

What is the PGAS? It's not in the glossary thread and I find nothing by googling it.

4
Glaciers / Re: Barnes Ice Cap / Penney Ice Cap
« on: August 13, 2019, 10:03:50 PM »
Think it will disappear in next 45 years? Or any other estimates for when it will disappear?

No way. This study suggests anywhere from 150 - 530 years: https://www.researchgate.net/publication/315457852_The_projected_demise_of_Barnes_Ice_Cap_Evidence_of_an_unusually_warm_21st_century_Arctic

5
Science / Re: 2019 Mauna Loa CO2 levels
« on: August 11, 2019, 09:33:07 PM »
July came in at 411.77 ppm.  That's a growth rate of 3.06 ppm.  Running 12-month growth rate average is now ~2.80 ppm/year and above the trend.  The rate of the growth rate (acceleration) is about 0.70 ppm/decade².

It looks like a wave with a very regular period, but it's not seasonal as the period is longer than a year.. What's up with that?

6
Arctic sea ice / Re: The 2019 melting season
« on: August 11, 2019, 05:09:19 PM »
You can see the effect of the blowtorch on the asian side on the island ice caps. Melting like crazy compared to 4 days ago.

7
Arctic sea ice / Re: The 2019 melting season
« on: August 11, 2019, 05:04:45 PM »
NSIDC for the 10 th puts sea ice extent at 5.093 M km^2 a drop of 166K km^2. 

Lowest on record!!!  2012 was lowest for just 2 days!.

2012 has lost its big chance to pull away and now its going to be a nail biting ride to the finish.

I don't understand. Looking at the Charctic chart 2012 hasn't been the lowest for some time.

Charctic uses 5-day averages. On daily values posted in the area and extent data thread it was lowest.

8
Arctic sea ice / Re: The 2019 melting season
« on: August 10, 2019, 07:59:29 AM »
August 5-9.
<gif>

Looks like we're starting to see the effects of the incoming heat around Bolshevik Island.

9
The forum / Re: WHY THE CRAZY QUESTIONS TO POST AND ENTER SITE
« on: August 09, 2019, 10:06:50 PM »
In all fairness, some of these questions are quite difficult to answer unless you have been lurking and reading the forum for a long while. I think they are filtering good potential users that have been sent off at the gate.
I think a fair solution would be to add a hint in the question, that a spambot will not be able to use.
What causes the ice to melt, 3 letters? (Hint: starts with Anthropogenic)
What was the name of the 2012 Arctic storm, 3 letters? (Hint: read the Arctic Sea Ice Blog post of date X 2012)
And so on.

Indeed. I never figured out that first one, I had never heard that acronym before I joined here. Had to refresh the page until I got a different question. The only fitting acronym I could think of was GHG (Greenhouse gases).

Another difficult one is "Which river flows into the Laptev Sea (4 letters)"? I'm guessing Lena is the actual answer, but Yana would in fact also be correct, in fact that's what shows up when I try to google "laptev sea river", like many would do when faced with this question: https://i.imgur.com/nICeGUX.png


10
Arctic sea ice / Re: meaningless freezingseason/melting season chatter.
« on: August 09, 2019, 08:44:46 AM »
Eye of a hurricane? No, this strange looking cloud is located in Baffin Bay!


11
Arctic sea ice / Re: The 2019 melting season
« on: August 07, 2019, 04:06:56 PM »

12
A calving? Today's view is not available on sentinel yet, but on worldview it looks like it:


13
Greenland and Arctic Circle / Re: Greenland 2019 Melt Season
« on: August 05, 2019, 04:05:49 PM »
Thanks G. In all honesty, I could never figure out the quirk with limiting the number of repetitions. I often find myself staring at a gif several times in a row, focusing each time on a different part. This is even more so when I use my phone. If it stops after a few, I usually need to reload it again, wasting bandwidth and energy.
It was all because some of the ASIF members have really lousy connections and even lousier limits on download limits.

So one of those things when some are going to be hacked off no matter what you do.

But how does limiting the number of playbacks help with this? After you've watched the animation one time, you don't have to download it again to watch it again, it can loop forever for free.

14
Arctic sea ice / Re: The 2019 melting season
« on: August 04, 2019, 07:23:56 PM »
Except for an area of the northern Barents sea between Svalbard and FJI which has been cooled by advection of ice into the waters, SSTs are anomalously high on the Atlantic side.<snip>

Yes, SST anomalies have gone crazy recently, on both the atlantic and the pacific side. Animation below for the past 6 weeks.


My naive reaction is that those anomalies around the CAA suggest that a complete melt out is possible there.

The thickness in most of the CAA is already very low according to PIOMAS, so I agree.

15
Arctic sea ice / Re: Latest PIOMAS update (August 2019)
« on: August 04, 2019, 02:43:16 PM »
If PIOMAS is calculated by what we see on Wip's first Animation-
then the Reality must be much worse:
no sign of the Break- up above CAA & Greenland, no Rubble in the ESS either.

That sloppy Resolution is just a Joke.

The animation is showing thickness only. The area data which is combined with thickness to produce volume, is separate.

16
Arctic sea ice / Re: The 2019 melting season
« on: August 03, 2019, 09:59:46 PM »
Both GFS and Euro predicts a huge intrusion of heat from the russian side starting at T+5 days.


17
Arctic sea ice / Re: The 2019 melting season
« on: August 03, 2019, 06:58:30 PM »
Anything other than the Parry Channel is cheating.

I see...  ???
Yeah, I mean the southern route (bottom line on the map).
Parry Channel will be more than a week... :)



Is it not also possible to go through here?

18
The rest / Re: Climate change activists should not fly
« on: August 02, 2019, 12:54:37 PM »
This subject is just silly.  Climate activists would not be able to get to meetings if they could not fly.

People have to work.  I fly a lot for my job.  People need to take vacations and often flying is the only way to do that.

We have this wonderful technology today that is video conferencing. Physical meetings are not really necessary anymore, people are just unwilling to change their habits.

People also don't *need* to take faraway vacations. That is an extravagant luxury that 90% of the world's population almost never does.

B.S. , human interaction and reading of nonverbal cues are as important pieces of information as ever. I agree trips should be minimized, but some work cannot be done from afar. 

Ok let's put aws in place to cage people in their 100 mile radius...your proposal will go very well...

You get 95% of all nonverbal cues through video. It is enough for pretty much all work-related purposes.

And yes, I think that would in fact go well. People would be mad, like a child being taken away his toys, but long term it would probably be best for humanity. It is an extreme measure, but the situation calls for extreme measures, because chances are the alternative is extinction. Of course this is all hypothetical, as people will never let such regulations happen, but I think that is a shortsighted, irrational and greedy decision.

19
Walking the walk / Re: When was the last flight you took?
« on: August 02, 2019, 10:17:01 AM »
Quote from: grixm
For one, airplane emissions contributes to the greenhouse effect around 2-4 times as much as emissions on the ground.

Source??

https://en.wikipedia.org/wiki/Environmental_impact_of_aviation#Total_climate_effects

And they give this as the primary source for that specific statement: http://www.grida.no/climate/ipcc/aviation/index.htm

20
The rest / Re: Climate change activists should not fly
« on: August 02, 2019, 10:11:22 AM »
This subject is just silly.  Climate activists would not be able to get to meetings if they could not fly.

People have to work.  I fly a lot for my job.  People need to take vacations and often flying is the only way to do that.

We have this wonderful technology today that is video conferencing. Physical meetings are not really necessary anymore, people are just unwilling to change their habits.

People also don't *need* to take faraway vacations. That is an extravagant luxury that 90% of the world's population almost never does.

21
Walking the walk / Re: When was the last flight you took?
« on: August 01, 2019, 09:43:00 PM »
car vs plane:

An average car runs 15000-20000 km / yr, using 1200-2000 liters of gasoline. Many families in the developed world have two cars, so an average family easily uses 2-3 or 4 thousand liters of gasoline

A family trip to Rome from London (just an example, 1500 km distance, 3000km two-way) uses cca 300-350 liters of kerosene for a family of four.

Let's say that your well of average family takes two trips like this per year, that is they use 600-700 liters of kerosene vs the 2-3-4 THOUSAND liters they use in their car(s).

I still don't see why we should bash airlines so much.

For one, airplane emissions contributes to the greenhouse effect around 2-4 times as much as emissions on the ground. That means that in your example the two trips actually likely equal the cars for a year, despite using less fuel. Secondly, I think having two cars is not as common as you make it seem, at least outside the US. Your mileage is also very high, many modern cars would only consume around 750 liters of gasoline for 15000 km, not to mention electric cars. All this means that for many families, one or two such airplane trips would equal several years of car use.

And finally, for many having a car is necessary, they can't easily get to or from work without it. But flying on a vacation is pure luxury, no one really needs it.

22
Greenland and Arctic Circle / Re: Greenland 2019 Melt Season
« on: July 31, 2019, 08:20:14 PM »
New high for the season in NSIDC melt extent too.

23
Nice animations Tor and Sterks. Note the 2017 typo.
Thanks, Ah didn't catch that, the Sentinel-hub app puts those labels. I'd swear these images are 2019

Are you sure about that? Looks to me like your pictures are indeed from 2017. Here's a gif comparison between 2017 and now (click). Notice the shape and position of the the edge, and compare to your image.

24
Greenland and Arctic Circle / Re: Greenland 2019 Melt Season
« on: July 30, 2019, 09:59:39 PM »
More melt ponds than any other day in the season so far at the Freya glacier webcam. 13.6C
 
https://www.foto-webcam.eu/webcam/freya1/

25
Arctic sea ice / Re: The 2019 melting season
« on: July 29, 2019, 10:35:46 AM »
There's no Point in posting HYCOM, as they switched from ArCc to Glb Models since about 2017. Especially when making Comparisons.
Glb seems to indicate much less thicker Ice than the previously used ArCc Model.

Interesting, that can explain the question I've had for a while on why 2012 is so far ahead of 2019, even though on PIOMAS they are roughly tied.
2019 is ahead of 2012 in PIOMAS and every other data set...

Which is precisely why it's strange that it's far behind in DMI's volume model (which uses HYCOM thickness)

26
Arctic sea ice / Re: The 2019 melting season
« on: July 29, 2019, 09:00:07 AM »
There's no Point in posting HYCOM, as they switched from ArCc to Glb Models since about 2017. Especially when making Comparisons.
Glb seems to indicate much less thicker Ice than the previously used ArCc Model.

Interesting, that can explain the question I've had for a while on why 2012 is so far ahead of 2019, even though on PIOMAS they are roughly tied.

27
Greenland and Arctic Circle / Re: Greenland 2019 Melt Season
« on: July 27, 2019, 09:51:38 PM »
NSIDC has a new interactive melt map where you can browse melt extent and temperature readings for different dates: https://greenland-measures.labs.nsidc.org/

28
Consequences / Re: Heatwaves
« on: July 27, 2019, 07:31:16 PM »
Norway's all-time record (35.6C) has been equaled: https://www.nrk.no/norge/den-norske-varmerekorden-fra-1970-er-tangert-1.14639854

And that in a relatively northern part of the country, 66⁰N

29
Arctic sea ice / Re: The 2019 melting season
« on: July 27, 2019, 08:24:16 AM »
Look at this melting in the Beaufort!

The biggest of these floes were over 10km long in the first picture, with sharp edges. Then two days later: Poof. Just unrecognizable foam.

30
Arctic sea ice / Re: The 2019 melting season
« on: July 27, 2019, 07:48:54 AM »
I value a model by its merits and if it shows 3m thick ice stay there and go to zero almost overnight, something is very very wrong.

When have the DMI thickness done that?

31
Arctic sea ice / Re: The 2019 melting season
« on: July 26, 2019, 10:10:56 PM »
For the first time in a long time we have a cloud-free view of the western CAA:


32
Greenland and Arctic Circle / Re: Greenland 2019 Melt Season
« on: July 26, 2019, 07:54:31 PM »
I was surprised to see that the upcoming potential greenland melt event made the top of my national news site NRK.no: https://i.imgur.com/e4Y4doz.jpg

I thought keeping up with this stuff was a bit too niche for mainstream media

33
Consequences / Re: Heatwaves
« on: July 26, 2019, 03:40:33 PM »
Several cities here in Norway, including my own, has broken their all-time records.
But temperatures are starting to plateau, and an all-time national record is still over 2C away. Not too late yet (and temps will stay high for the next 2-3 days) but it's not as likely as yesterday's forecast suggested, anymore.

EDIT: Peaked today 1.4C below national record.

34
Arctic sea ice / Re: The 2019 melting season
« on: July 26, 2019, 11:12:09 AM »
Well the edge of the Beaufort ice is melting rapidly. Lots of area of slush simply vanished in 24 hours: https://go.nasa.gov/2K4kowV

35
Consequences / Re: Heatwaves
« on: July 25, 2019, 06:21:07 PM »
Now Norway is forecast to break the all-time national record too. Record is currently 35.6C, while at least Voss may reach 37C tomorrow.

https://www.yr.no/en/forecast/daily-table/1-109644/Norway/Hordaland/Voss/Voss

36
Arctic sea ice / Re: The 2019 melting season
« on: July 25, 2019, 01:36:39 PM »

Therefore it is totally meaningless to look at 2m temp-anomalies over the CAB and conclude from a minor positive anomaly that there is no massive heat influx into the CAB. Even a +1°C anomaly can mean a lot of heat/insolation.

So what evidence would you look for to prove that a massive heat influx is actually taking place?


850 / 925 hPa temperatures.

37
Greenland and Arctic Circle / Re: Greenland 2019 Melt Season
« on: July 25, 2019, 08:18:10 AM »
If the 0z GFS verifies, Greenland will see an extreme melt event starting at +120h. At daytime 90% of the island will have above freezing surface air temperature and the coast will reach 20C+, all lasting several days!


38
Consequences / Re: Heatwaves
« on: July 24, 2019, 08:38:23 AM »
We're looking at potential records here in Scandinavia too. In Bergen, western Norway, it is currently forecast to reach 34 C on Friday. That would smash the previous all-time record of around 32C (which was set just last year).

39
Arctic sea ice / Re: Arctic Image of the Day
« on: July 23, 2019, 07:14:03 PM »
Baffin Bay full of scattered icebergs looks like the starry night sky. Quite beautiful.

https://i.redd.it/1zaxpynw53c31.jpg


40
Arctic sea ice / Re: The 2019 melting season
« on: July 22, 2019, 09:00:57 PM »
GFS max 2m temps for the next 10 days are 2-3C where most of the ice is located. Average temps are obviously lower. Enough to keep melt going steadily, but nothing epic as far as I can tell.

Wouldn't the ice peg the surface temperature to around that level regardless of how much melt is going on? Since melting ice absorbs heat energy from the surroundings. I think something like 850hpa temps are more indicative of the actual stress the ice experiences.

41
Arctic sea ice / Re: The 2019 melting season
« on: July 21, 2019, 08:09:44 PM »
12z euro running now. Matching the GFS so far at 72h

42
Arctic sea ice / Re: The 2019 melting season
« on: July 21, 2019, 06:56:27 PM »
GFS 12z doesn't mess around... A huge high pressure area spanning the entire arctic sea starts forming at around +72h, and stays the entire rest of the run (at least up to the 312h processed so far).

I think this is what the kids would describe as "whack".


43
Arctic sea ice / Re: The 2019 melting season
« on: July 20, 2019, 09:53:50 AM »
There's a pretty cool contrast in the Nares strait between the previously fast ice that has nearly melted through, and the exported ice floes that are still pretty thick:


44
Arctic sea ice / Re: The 2019 melting season
« on: July 19, 2019, 03:44:22 PM »
How does DMI see ice that is over 2 and 3 meters thick in the region I circled?
Its all rubble...

I try an explanation, and I stop with DMI on this topic.
I think it IS 2 and 3 meters thick in Beaufort now, but indeed, in rubbles. But DMI fails to see spaces between floes.
So, where there are thick floes, it seas thick whole area, and overestimates volume. And in Beaufort now, it particularly overestimates volume because floes are thick.

I suppose when ice is covering smoothly all the area, DMI doesn't overestimate volume.
It could explain why it didn't overestimate volume in 2008, ice was thin in some important areas, but surface concentration was good.

The map only shows thickness, not concentration, and DMI uses concentration data combined with the thickness to estimate volume. So it doesn't overestimate or underestimate volume based on how concentrated the ice is.

45
Greenland and Arctic Circle / Re: Greenland 2019 Melt Season
« on: July 18, 2019, 06:03:37 PM »
Next few days will be hot in Greenland. Will probably see another spike in melt. Some precip too though, so don't know how the SMB will end up.

46
Arctic sea ice / Re: The 2019 melting season
« on: July 18, 2019, 08:30:08 AM »
The DMI volume chart is hopeless, at best a week or 2 out of date. It's showing a ice over half a meter in open water in the Laptev bite today, and great swathes of ice in Baffin Bay in these 2 maps dated 16 July from Bremen and DMI - though what date the DMI really refers to, who knows

I've attached the comparison as both a gif(click to and an mp4. The MP4 plays fine locally but its been a bit of a lottery trying to get them to play on the forum, at least in my browser

I think maybe the DMI map is not trying to show exact extent, merely the estimated thickness if there had been any ice there, and then when calculating volume it combines that with separate data for area, to get volume. This means that where the ice area/extent is near zero, volume will also be near zero, even if the thickness map shows a significant thickness there.

For this reason I think it is also exaggerating the extent in which it does thickness modeling, to cover absolutely everything, even scattered rubble. You can f.ex. see in worldview that there is still ice in the middle of the Baffin bay, floes several kilometers wide. These may be old ice floes exported through the Nares strait, which started out many meters thick, so it's fair to assume they still have some significant thickness left, like the model estimates. It's just that they are so few that they are below the 10% extent cutoff that Bremen/NSIDC etc uses.

47
Arctic sea ice / Re: The 2019 melting season
« on: July 17, 2019, 06:42:15 PM »
The polynya north of Greenland keeps growing, and fast ice is shattering.
Also lots of cracks that weren't there yesterday, in the ice to the west, outside the Nares strait.

https://go.nasa.gov/2JABGmq



48
Arctic sea ice / Re: 2019 vs 2012
« on: July 16, 2019, 08:35:43 AM »
DMI's thickness model shows pretty different results to PIOMAS. Where PIOMAS has 2012 and 2019 pretty much tied for volume at this point, 2019 is lagging pretty far behind according to DMI: (click to play)

I asked what the difference between these models are in the PIMOAS thread and why no one seems to talk about DMI, didn't get a response.

49
Greenland and Arctic Circle / Re: Greenland 2019 Melt Season
« on: July 15, 2019, 09:17:45 AM »
So basically we are pretty much at the mean minimum accumulated SMB already, and we're just halfway through the season!

50
Arctic sea ice / Re: When will the Arctic Go Ice Free?
« on: July 14, 2019, 04:36:31 PM »

Seems like you are trusting your gut instead of the result of modelling.
Should I put my trust in a projection based on a 4 parameter Gompertz equation?
Any more than I should put my trust in the attached?

Probably not.  However the Gompertz does a better job of fitting the observation data.  Is that just coincidence?  On the other hand, is there any reason to suspect a straight line decline?  In any case, the largest rate of decline occurred over a roughly 10-year period, from 1998 - 2007.  The decades both before and after have shown much less melt.  Perhaps we are trying to apply a mathematical fit, where none exists.  I think the ice will continue to decline, but in method between the two fits; less than the straight line, but more than the Gompertz.  However, I could be just as wrong as the many others before who tried to predict the Arctic sea ice.

A 4 parameter gompertz is a far more complicated equation than the 2 parameter straight line. When allowed complexity rises the pool of possible functions that fit the observed data also rises, but the chance of such a fit being genuine and not a coincidence also falls, because of overfitting. Thus, when several equations fit the observed data reasonably, the least complex of them is more likely to be more correct, that's Occam's razor.

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