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viddaloo

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Re: Arctic Refreeze Discussion: 2014/2015
« Reply #50 on: October 25, 2014, 03:50:42 AM »
I could look in the Melt Season thread, but does anyone know if the Gyre changed direction 2–3 times this year?
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ChrisReynolds

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Re: Arctic Refreeze Discussion: 2014/2015
« Reply #51 on: October 25, 2014, 08:15:20 AM »
I could look in the Melt Season thread, but does anyone know if the Gyre changed direction 2–3 times this year?

The Gyre is driven by winds, so you'd need to start with the atmosphere. However this summer the conditions have been largely anticyclonic which favours the gyre and retention of fresh water in the gyre. Whether transient summer lows passing over Beaufort would persist for long enough to reverse the gyre and releaase the fresh water dome I do not know.

BornFromTheVoid

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Re: Arctic Refreeze Discussion: 2014/2015
« Reply #52 on: October 28, 2014, 04:25:26 PM »
Looks like we've passed the period of maximum growth rate, topping out at 1.06million km2.



This is slightly above the long term average (81-10) of 981k, but below the average of the last 10 years, of 1.139m

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Rubikscube

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Re: Arctic Refreeze Discussion: 2014/2015
« Reply #53 on: October 28, 2014, 05:27:11 PM »
The amount of ice in Kara is really standing out at the moment, continuing this seasons trend of above normal amounts of "Atlantic ice". On the other end of the scale, the ESS is now lagging behind three out of the four years and there is still an apparent lack of export through farm. Refreeze has also begun in Baffin where the amounts of ice seems on pair with those of recent years.

In addition to 2007, 2012 and 2013, I've this week added a comparison with 2010.
« Last Edit: October 28, 2014, 05:32:52 PM by Rubikscube »

viddaloo

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Re: Arctic Refreeze Discussion: 2014/2015
« Reply #54 on: October 29, 2014, 11:05:30 PM »
This week we saw the Yearly Average Extent go from decreasing daily drops to slowly increasing gains, the last one up 234 km²/day — and weekly we're now down only 298. For the past 30 days the net change is down 18 760 km². We're still below 10.3 million km², and only 4 previous years have ever been this low. (2014 will be the 4th year with a calendar year YAE below 10.3, but the first of those to not set an Autumn all–time low.)

The current Big Descent that began on January 5th 2014 has removed 120 581 km² from yearly averages. During November we will probably pass the July 14th yearly low–point of 10.2978. Today's YAE is 49 314 km² lower than 2013 for the same day (Oct 28th), and it will be another 85 days before 2009(10) is that low compared to 2008(9), on January 21st.

The forecast has changed to October 21st 2016 as the low–point of this long descent, and a current estimate for this date of 9.4 m km² — a loss of 1.02 m km² of Arctic sea ice since the beginning of the descent, on January 5th of this year. If correct, this will be the biggest descent in IJIS history.

First graph below shows 2014 + 2009 detail. The second presents the general overview.

Next week we'll likely have the PIOMAS data for October, but estimates show the Yearly Average Volume is still up, and that no descent, small or big, has yet started for average volume. Instead, the Yearly Average Volume has interestingly gone from 3rd lowest to 5th lowest during a 2014 where Yearly Average Extent has gone the other way, from 6th lowest to 4th lowest in October.

My question to all of you is thus why average volume is rising in a year where average extent is falling and losing more than 120 000 km². And for the really adventurous out there: Will average volume follow extent and start a Big Descent (my bet), or will average extent instead turn around to follow volume and start an ascent?
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iceman

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Re: Arctic Refreeze Discussion: 2014/2015
« Reply #55 on: October 30, 2014, 01:11:50 PM »
  ....
My question to all of you is thus why average volume is rising in a year where average extent is falling ....

Good question, partially answered in Neven's latest PIOMAS blog post and elsewhere.  Most of the volume rebound has been in the central region of the ice pack, where it is not directly affected by area/extent except near the minimum.
     If you look a the volume anomaly chart, the departure from recent years' trends began in early June and persisted through mid-August.  Various explanations have been mooted that would be consistent with that time interval.  If we could unpick the causal chain among them, we'd be a lot farther toward a physical basis for predictions.

viddaloo

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Re: Arctic Refreeze Discussion: 2014/2015
« Reply #56 on: October 30, 2014, 07:23:48 PM »
You're probably right about the CAB being central to this minor paradox, but through the year the story is a bit more complex (see graph below). While average extent deltas have been around and mostly below zero (2013s data) for the entire year, volume deltas have been way over zero all year except March, April and May.

There's also a fairly recent trend that 2014 is strengthening and extending, and that is the slow July–August melt, explored in this thread.
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BornFromTheVoid

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Re: Arctic Refreeze Discussion: 2014/2015
« Reply #57 on: November 04, 2014, 04:10:49 PM »
A massive jump of 259.8k on the NSIDC extent puts 2014 up to the highest since 2001.

Don't think that's happened since the end of May last year.
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DavidR

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Re: Arctic Refreeze Discussion: 2014/2015
« Reply #58 on: November 06, 2014, 08:12:52 AM »
     If you look a the volume anomaly chart, the departure from recent years' trends began in early June and persisted through mid-August.  Various explanations have been mooted that would be consistent with that time interval.  If we could unpick the causal chain among them, we'd be a lot farther toward a physical basis for predictions.
If you look at Arctic temperatures over summer http://www.esrl.noaa.gov/psd/cgi-bin/data/timeseries/timeseries.pl?ntype=1&var=Air+Temperature&level=1000&lat1=90&lat2=67&lon1=0&lon2=360&iseas=0&mon1=0&mon2=11&iarea=0&typeout=1&Submit=Create+Timeseries its fairly  clear that a major factor was that the Arctic summer was comparatively cool.  June in particularly  cool rating at 44th warmest  in the last 66 years a full 1.5 degrees colder on average than 2012. 
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viddaloo

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Re: Arctic Refreeze Discussion: 2014/2015
« Reply #59 on: November 06, 2014, 08:47:35 AM »
Any idea as to why June was so cold? Maybe too much wildfire smoke for the sun to warm it?

Here's June compared to the 1979–1999 average:
« Last Edit: November 06, 2014, 09:17:30 AM by viddaloo »
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Wipneus

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Re: Arctic Refreeze Discussion: 2014/2015
« Reply #60 on: November 06, 2014, 09:08:40 AM »
A massive jump of 259.8k on the NSIDC extent puts 2014 up to the highest since 2001.

Don't think that's happened since the end of May last year.

Lots of false ice in Sea of Okhotsk (Nuri?). Some has disappeared again in yesterdays update, with a drop in total extent of -22k, Okhotsk contribution -75k.

jdallen

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Re: Arctic Refreeze Discussion: 2014/2015
« Reply #61 on: November 06, 2014, 06:08:59 PM »
Any idea as to why June was so cold? Maybe too much wildfire smoke for the sun to warm it?

Here's June compared to the 1979–1999 average:

Cloud cover more likely, IIRC.

Tangent - does the Refreeze of the Hudson and central/southern Baffin bays seem behind schedule?  Seems a lot of open water approaching mid November.
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BornFromTheVoid

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Re: Arctic Refreeze Discussion: 2014/2015
« Reply #62 on: November 07, 2014, 02:11:17 PM »
A massive jump of 259.8k on the NSIDC extent puts 2014 up to the highest since 2001.

Don't think that's happened since the end of May last year.

Lots of false ice in Sea of Okhotsk (Nuri?). Some has disappeared again in yesterdays update, with a drop in total extent of -22k, Okhotsk contribution -75k.

I hadn't considered Nuri. Yeah, it's grown to a 2 day pause now and the 5 day mean remains below 2008.
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Michael Hauber

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Re: Arctic Refreeze Discussion: 2014/2015
« Reply #63 on: November 07, 2014, 11:14:33 PM »
Wow at the latest GFS.  +4 850hp temps in the Beaufort sea?  It may not yet be officially winter yet, but DMI 80n shows that average temps this year are about 80% of the way towards

The worst of it is at the end of the 7 day run, but even with significant downgrades we could see near freezing temps along the Beaufort coast, and a week of offshore winds could open up some noticeable water.

Climate change:  Prepare for the worst, hope for the best, expect the middle.

jdallen

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Re: Arctic Refreeze Discussion: 2014/2015
« Reply #64 on: November 08, 2014, 08:29:05 AM »
Wow at the latest GFS.  +4 850hp temps in the Beaufort sea?  It may not yet be officially winter yet, but DMI 80n shows that average temps this year are about 80% of the way towards

The worst of it is at the end of the 7 day run, but even with significant downgrades we could see near freezing temps along the Beaufort coast, and a week of offshore winds could open up some noticeable water.
I'm not following you Michael.  What are you getting at?
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JayW

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Re: Arctic Refreeze Discussion: 2014/2015
« Reply #65 on: November 08, 2014, 11:17:57 AM »
Wow at the latest GFS.  +4 850hp temps in the Beaufort sea?  It may not yet be officially winter yet, but DMI 80n shows that average temps this year are about 80% of the way towards

The worst of it is at the end of the 7 day run, but even with significant downgrades we could see near freezing temps along the Beaufort coast, and a week of offshore winds could open up some noticeable water.
I'm not following you Michael.  What are you getting at?

I don't want to speak for Michael, but I do watch weather models a lot because I like snowstorms  :)

I I think he's suggesting the north shore of Alaska could get above freezing.  I've been curious about this too.
 
The flow over north America is expected to become very blocky with a large amount of warm air forced into Alaska and north.  Coinciding with the large chill over the central-eastern US. Lasting a week+

GFS ensembles 850mb temp anomalies


850 temp std. dev.


http://www.esrl.noaa.gov/psd/map/images/ens/t850anom_f144_nh.html




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Rubikscube

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Re: Arctic Refreeze Discussion: 2014/2015
« Reply #66 on: November 08, 2014, 11:53:14 AM »
The euro is also quite harsh, it seens that an initial wave of warm air from the masive bering storm eventually will result in a cutoff system over Alaska, (120-144h range), then in the 168h+ range this cutoff high meanders deep into the arctic, basically pushing all the cold down Canada and Siberia. The Pacific refreeze will certainly be delayed quite a bit, and if the forecast go all the way (which is of course a bit unlikely), some seriously high 80N temps should be expected.

jdallen

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Re: Arctic Refreeze Discussion: 2014/2015
« Reply #67 on: November 08, 2014, 06:54:05 PM »
The euro is also quite harsh, it seens that an initial wave of warm air from the masive bering storm eventually will result in a cutoff system over Alaska, (120-144h range), then in the 168h+ range this cutoff high meanders deep into the arctic, basically pushing all the cold down Canada and Siberia. The Pacific refreeze will certainly be delayed quite a bit, and if the forecast go all the way (which is of course a bit unlikely), some seriously high 80N temps should be expected.

Thank you Jay and Rubic.

That makes sense, considering the huge volume of "warm" moist air Nuri is dragging along.  It is in line with what I've been imagining; nice to have that thinking confirmed.

Most people who experience arctic breakouts don't think as deeply about them as to realize the air that came from the arctic, had to be *replaced* in the arctic.  In this case, the replacement will be air as much above normal as the arctic breakout is below. 

Time to start tracking freezing degree days, I think.  I also think I may want to see what I can find about precipitation over the pack.  Significant snowfall on it this early is not likely to be good for later thickening.
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flyoverice

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Re: Arctic Refreeze Discussion: 2014/2015
« Reply #68 on: November 09, 2014, 02:40:39 AM »
In watching the nsidc SIE data I just noticed that total NH and SH area is as high as 1984 for day 311 of 2014. Is this a sign of recovery of sea ice globally? Arctic being 380k sq km below 1984 and the Antarctic being 420k sq km above 1984 level. Or is the volume still extremely depleted at the Arctic?

OSweetMrMath

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Re: Arctic Refreeze Discussion: 2014/2015
« Reply #69 on: November 09, 2014, 05:12:23 AM »
I have been posting regular updates on my predictions for the minimum NSIDC extent and PIOMAS volume on the appropriate prediction threads. Since we've passed this year's minimum, I've started predicting maximum values. In the absence of another obvious place to post, I'm posting my predictions here.

Last month's prediction for the October average PIOMAS volume was 8000 cubic km. The reported value was 8159 cubic km, high but inside my confidence interval. This increases my prediction for the April average volume to 23,800 cubic km, with 95% confidence interval of 22,100-25,600 cubic km.

Last month's prediction for the October average NSIDC extent was 7.8 million sq km. The reported value was 8.06 million sq km, again high but inside my confidence interval. This increases my prediction for the March average extent to 14.8 million sq km, with 95% confidence interval of 14.1-15.5 million sq km.

JayW

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Re: Arctic Refreeze Discussion: 2014/2015
« Reply #70 on: November 09, 2014, 02:09:14 PM »
The euro is also quite harsh, it seens that an initial wave of warm air from the masive bering storm eventually will result in a cutoff system over Alaska, (120-144h range), then in the 168h+ range this cutoff high meanders deep into the arctic, basically pushing all the cold down Canada and Siberia. The Pacific refreeze will certainly be delayed quite a bit, and if the forecast go all the way (which is of course a bit unlikely), some seriously high 80N temps should be expected.

Thank you Jay and Rubic.

That makes sense, considering the huge volume of "warm" moist air Nuri is dragging along.  It is in line with what I've been imagining; nice to have that thinking confirmed.

Most people who experience arctic breakouts don't think as deeply about them as to realize the air that came from the arctic, had to be *replaced* in the arctic.  In this case, the replacement will be air as much above normal as the arctic breakout is below. 

Time to start tracking freezing degree days, I think.  I also think I may want to see what I can find about precipitation over the pack.  Significant snowfall on it this early is not likely to be good for later thickening.

I have seen a lot of talk about the Siberian snow cover and the SAI and OPI causing the Arctic oscillation to tank this winter, making it a cold winter. And I will note that this is different than last year which featured a predominately positive AO .

As a Mainer, these Teleconnections often don't line up with the rest of the east coast.  ;)

Attached are the temperature linear correlations with regard to AO for DJF

http://www.esrl.noaa.gov/psd/data/usclimdivs/correlation/
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Michael Hauber

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Re: Arctic Refreeze Discussion: 2014/2015
« Reply #71 on: November 09, 2014, 08:11:57 PM »


I I think he's suggesting the north shore of Alaska could get above freezing.  I've been curious about this too.
 
The flow over north America is expected to become very blocky with a large amount of warm air forced into Alaska and north.  Coinciding with the large chill over the central-eastern US. Lasting a week+


Its not just the warmth, but the offshore wind which will push ice away from the Alaskan coast.  With the temps close to freezing - even if its not high enough to melt ice I doubt it will be cold enough to freeze back over until the pattern ends.
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JayW

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Re: Arctic Refreeze Discussion: 2014/2015
« Reply #72 on: November 10, 2014, 12:01:22 PM »

Its not just the warmth, but the offshore wind which will push ice away from the Alaskan coast.  With the temps close to freezing - even if its not high enough to melt ice I doubt it will be cold enough to freeze back over until the pattern ends.

When does the pattern end?  This block is looking tough. And, you are right about the winds. Also, with the AO going negative, and likely to remain there, won't Fram export be on the increase.  Looking at Wipneus' PIOMAS update for October, a decent fraction of areas that increased in thickening from 2013-2014 is in close proximity to the Fram.

I know these forecasts are for 10 days out, so the normal caveats apply, but it's quite a blocky pattern, it should persist.

Attachment 1 GFS ensemble 850hpa temp anomalies hr 240
http://www.esrl.noaa.gov/psd/map/images/ens/t850anom_f240_nh.html

Attachment 2 EURO ensembles 850hpa temp anomalies hr 240 (the deterministic has 20°C+ anoms north of Alaska)
http://www.meteociel.fr/modeles/ecmwf.php?ech=240&mode=100&map=1&type=1&archive=0
« Last Edit: November 10, 2014, 12:31:40 PM by JayW »
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viddaloo

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Re: Arctic Refreeze Discussion: 2014/2015
« Reply #73 on: November 10, 2014, 05:34:35 PM »
Don't think Nuri is the only one to blame here: Notice the sharp increase in mean CH4, and the subsequent decrease in refreeze (both extent and volume). Also note the sharp fall in 2013 extent and volume, following a 2600 ppb CH4 event last year.
« Last Edit: November 10, 2014, 05:40:10 PM by viddaloo »
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ChrisReynolds

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Re: Arctic Refreeze Discussion: 2014/2015
« Reply #74 on: November 10, 2014, 09:27:30 PM »
A relevant October/November blog post is now available.

http://dosbat.blogspot.co.uk/2014/11/mid-november-status.html

jdallen

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Re: Arctic Refreeze Discussion: 2014/2015
« Reply #75 on: November 10, 2014, 09:38:30 PM »
Don't think Nuri is the only one to blame here: Notice the sharp increase in mean CH4, and the subsequent decrease in refreeze (both extent and volume). Also note the sharp fall in 2013 extent and volume, following a 2600 ppb CH4[/url] event last year.

I really don't think the CH4 release would have that prompt an effect, even with a temporary 30% increase in concentration.  It's not being pumped fast enough, high enough into to the atmosphere, nor do I think it is remaining concentrated long enough to seriously impede energy exiting the atmosphere.

I'll offer an additional observation - the block of atmosphere that CH4 got injected into, most likely is no longer over the arctic.  The displacements from the storms with almost complete certainty have driven that air out of the Arctic, and over the continents in the breakouts we currently are watching.  If there is a prompt effect, it would most likely  be to ablate the severity of the breakout(s).

http://chriscolose.wordpress.com/2008/11/10/methane-and-co2/

*Long* term, as overall concentrations increase steadily, it will have more of an effect.  Physics doesn't support prompt releases over what are relatively "small" areas having a dramatic direct effect on the ice or the weather.

There are other very clear sources - tropical moisture, wind, sensible heat in direct transfer of atmosphere from temperate latitudes to the arctic - for the extra energy to produce the observed changes (or lack there of), which frankly dwarf the short term effect of a methane release.

I'll add an observation: the blocks of atmosphere which picked up that methane most likely are no longer over the arctic.  The air displaced by Nuri et. al. has no doubt driven down over the continents.  The prompt effect of the methane at most might take some of the edge off of the cold they are starting to feel over the Mississippi valley.
« Last Edit: November 10, 2014, 09:50:01 PM by jdallen »
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viddaloo

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Re: Arctic Refreeze Discussion: 2014/2015
« Reply #76 on: November 10, 2014, 09:45:49 PM »
For sure, the graph doesn't say CH4 caused the slow refreeze (in November 2013 or this year), there could just as well be a common cause of both the CH4 release and the refreeze change (eg wind, waves).
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viddaloo

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Re: Arctic Refreeze Discussion: 2014/2015
« Reply #77 on: November 11, 2014, 01:46:04 AM »
However, CH4 from submarine permafrost is also transformed by bacteria into CO2, which we do know has a blanket effect, even in Winter. So parts of the hydrates cause spikes in the measured CH4 levels, while other parts cause increased CO2, that melts ice, or prohibits ice refreeze.

The Arctic Ocean also emits CO2 these days, as verified by eg the Swerus expedition this summer. I know warmer oceans emit more CO2, but I don't know to what extent warmer Winter waters or Autumn storms in Arctic will actually put out more CO2?
« Last Edit: November 11, 2014, 02:10:21 AM by viddaloo »
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jdallen

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Re: Arctic Refreeze Discussion: 2014/2015
« Reply #78 on: November 11, 2014, 05:22:22 AM »
However, CH4 from submarine permafrost is also transformed by bacteria into CO2, which we do know has a blanket effect, even in Winter. So parts of the hydrates cause spikes in the measured CH4 levels, while other parts cause increased CO2, that melts ice, or prohibits ice refreeze.

The Arctic Ocean also emits CO2 these days, as verified by eg the Swerus expedition this summer. I know warmer oceans emit more CO2, but I don't know to what extent warmer Winter waters or Autumn storms in Arctic will actually put out more CO2?
Not enough to cause significant (greater than 0.1C) increases in local temperature.  You are starting to sound silly, or argumentative, I'm not sure which, or both.

At the very least, your sense of scale is off. CH4 release is a huge problem, but one which will evolve over a time scale of decades, not days.
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viddaloo

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Re: Arctic Refreeze Discussion: 2014/2015
« Reply #79 on: November 11, 2014, 05:34:04 AM »
JD, it's a simple yes-or-no question, so no reason to go into full personal attack mode.

With the mentioned 2600 ppb CH4 event in early November 2013, there was a first ever net melt from one day to the next. That was the only November day of net melt of Arctic sea ice in the whole 1979—2014 time series.

Silly to me would be to automatically assume this to be mere coincidence.
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Re: Arctic Refreeze Discussion: 2014/2015
« Reply #80 on: November 11, 2014, 06:41:42 AM »
JD, it's a simple yes-or-no question, so no reason to go into full personal attack mode.

With the mentioned 2600 ppb CH4 event in early November 2013, there was a first ever net melt from one day to the next. That was the only November day of net melt of Arctic sea ice in the whole 1979—2014 time series.

Silly to me would be to automatically assume this to be mere coincidence.
It is not a personal attack.  It *is* a reaction to persistent misinterpretation of facts and events. You ask a lot of good questions, and make some good connections.  Other times, even in the face of pretty clear evidence that undermines an assertion you make, you persist in digging yourself in deeper.

That's what I'm reacting to.

I assure you, you are getting nothing like what I'd deliver in "full personal attack mode".  It has been known to blister paint (never in this venue), and reserve it for those who truly deserve it.  You're not on that list.

;)

Best regards...
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viddaloo

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Re: Arctic Refreeze Discussion: 2014/2015
« Reply #81 on: November 11, 2014, 06:53:30 AM »
I just believe we all learn more if we can think out loud and ask questions without the fear of ridicule and recreational comments about certain questions being silly. I come from a (mainly) non–religious family and culture and don't particularly appreciate taboos or dogmas when physics and chemistry are involved. To me you can believe whatever you want happens to the CH4 molecules before they 'go to heaven', but please keep it to yourself if it's only based in some sort of organized religion.
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ChrisReynolds

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Re: Arctic Refreeze Discussion: 2014/2015
« Reply #82 on: November 11, 2014, 06:48:56 PM »
I just believe we all learn more if we can think out loud and ask questions without the fear of ridicule and recreational comments about certain questions being silly. I come from a (mainly) non–religious family and culture and don't particularly appreciate taboos or dogmas when physics and chemistry are involved. To me you can believe whatever you want happens to the CH4 molecules before they 'go to heaven', but please keep it to yourself if it's only based in some sort of organized religion.

Requiring you to present a substantive case is not dogma.

1) November? One Day melt? Was this really melt?

2) Given temperatures at that time, is it reasonable to suspect actual melt of ice? i.e. was temperature significantly above zero degC.

3) Where did the reduction in extent/area occur? Can this be supposed to be linked to a localised methane source?

4) What is the probability of these two events occurring simultaneously (by random chance)?
« Last Edit: November 11, 2014, 09:23:05 PM by ChrisReynolds »

ChrisReynolds

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Re: Arctic Refreeze Discussion: 2014/2015
« Reply #83 on: November 11, 2014, 09:48:56 PM »
NSIDC Extent, number of days from 1979 to 2013 in November that have a decline in extent from preceding day.

01-Nov   0
02-Nov   1
03-Nov   4
04-Nov   3
05-Nov   6
06-Nov   4
07-Nov   8
08-Nov   4
09-Nov   5
10-Nov   4
11-Nov   3
12-Nov   5
13-Nov   3
14-Nov   4
15-Nov   2
16-Nov   3
17-Nov   4
18-Nov   5
19-Nov   4
20-Nov   3
21-Nov   5
22-Nov   1
23-Nov   2
24-Nov   1
25-Nov   1
26-Nov   1
27-Nov   6
28-Nov   2
29-Nov   2
30-Nov   0
   
Sum   96
Count   1050
Prob   9%

Probability of 9% of any day in November showing a decline in volume.

PIOMAS is more monotonic. Only 7 November 2013 shows a decline on previous day, but the decline is so small (-0.004k km^3) that considering PIOMAS uncertainty the most favourable conclusion is that it is a levelling. The next four days have an average decline of 0.060k km^3, average decline from 1979 to 2013 being 0.090k km^3 for those four days (8 to 11 Nov).

viddaloo

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Re: Arctic Refreeze Discussion: 2014/2015
« Reply #84 on: November 12, 2014, 01:08:10 AM »
PIOMAS volume is what we're talking about, so I can only guess why you choose to list the extent deltas instead. Is it really melt if it melts? Well, yes. Even if it's a small melt, it's still a melt, and singular in this case. It was the only November day that had a decline in volume from the previous day, and it happened during a period of high methane.

As I already pointed out it is a single day, so listing the following days and saying they had no melt, surprises no–one, really.

You see dogmas and taboos when someone is fighting rigorously against even the notion that two phenomena could be related, and when words are intentionally twisted beyond recognition («Requiring you to present a substantive case is not dogma.»). Dogmatic religion or group–think is then to be assumed, if not outright hatred of the messenger, for whatever reason. The important function of the attacks is to prevent others reading them from thinking undogmatically, inducing in them the fear of getting a similar response from dogmatic haters.

This is basic psychology, folks.

«1) November? One Day melt? Was this really melt?»

Yes, November is a month, the 11th in the year, yet I can see the need for even questioning this, given the level of taboo here. And yes, there was melt one day. Yes, really melt. Why is it so hard to accept?

«2) Given temperatures at that time, is it reasonable to suspect actual melt of ice? i.e. was temperature significantly above zero degC.»

Feel free to suggest other ways of making ice disappear other than through melting, if it's that important to you.

«3) Where did the reduction in extent/area occur? Can this be supposed to be linked to a localized methane source?»

Again, if you read my actual words, I'm not saying CH4 caused it directly, only that it happened simultaneously. There are a number of ways in which this may happen.

«4) What is the probability of these two events occurring simultaneously (by random chance)?»

Very close to zero. You have 35*30+10 = 1060 days and it happened once. That once was in a high CH4 period.

Basically, your attacks are strawman attacks, challenging a notion that was never actually suggested. They're also anti–scientific in the sense that you wish to limit — through ridicule etc — the scope of scientific investigation using whatever recreational pseudo–arguments that come to mind («CH4 release is a huge problem, but one which will evolve over a time scale of decades, not days.»).

The lady doth protest too much, methinks.

In any case, here is todays graph. Go nuts! :)
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jdallen

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Re: Arctic Refreeze Discussion: 2014/2015
« Reply #85 on: November 12, 2014, 06:03:21 PM »
Don't think Nuri is the only one to blame here: Notice the sharp increase in mean CH4, and the subsequent decrease in refreeze (both extent and volume). Also note the sharp fall in 2013 extent and volume, following a 2600 ppb CH4 event last year.
It seems pretty clear to me from this, that is exactly what you are saying - that prompt release of CH4 had an immediate effect on the pack.  We are not mistaking you. No taboo nonsense.
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Peter Ellis

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Re: Arctic Refreeze Discussion: 2014/2015
« Reply #86 on: November 12, 2014, 06:28:24 PM »
«1) November? One Day melt? Was this really melt?»

Yes, November is a month, the 11th in the year, yet I can see the need for even questioning this, given the level of taboo here. And yes, there was melt one day. Yes, really melt.
How do you know?  What is your evidence?

What you've posted so far is PIOMAS figures.  PIOMAS is a an estimate of what a computer program believes the volume to be, based on numerical modelling, and informed by satellite measurements of area and extent.  It is not actual data on volume.

We already know that the area and extent measurements are noisy, particularly during stormy weather, and can show quite large fluctuations from day to day, which will then be propagated into the PIOMAS model.

So, I repeat, what is your evidence that there really has been melt, and that this is in the same area and at the same time as the methane release?  And do you have any answer to the calculations showing that a release of methane cannot possibly have any localised effect on the local heat budget that's large enough to affect sea ice melting?

The local effect of methane at these concentrations is negligible - what matters is the aggregate effect over weeks/months/years in the atmosphere, at a global scale. You are, quite literally, claiming that farting in your garden will make your pond melt.

[Back of envelope calculation: average fart volume = ~1 litre per day, ~10% of which is methane. These supposed methane events in the Arctic involve concentrations changing by a few hundred ppb in one layer of the atmosphere.  That corresponds to diluting a fart into a volume ~10m x 10m x 10m, which is near enough the surface layer above a suburban garden pond.

So, I have an experiment for you.  Some time this winter, find a friendly neighbour whose pond has frozen over and spend a day farting above it, and see if it melts.]

viddaloo

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Re: Arctic Refreeze Discussion: 2014/2015
« Reply #87 on: November 12, 2014, 07:07:02 PM »
Peter Ellis, your hateful ad hominem attacks are not appreciated.
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ChrisReynolds

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Re: Arctic Refreeze Discussion: 2014/2015
« Reply #88 on: November 12, 2014, 08:00:05 PM »
Viddaloo,

1) You have one day of actual PIOMAS volume reduction on a day to day basis. The rest you seem to base your claim of a volume loss is actually an anomaly of volume. In both graphs you present it is stated that volume is 'relative to 2002 to 2013 Volume and Extent'. So your claimed volume loss is not necessarily a loss of volume, it is actually a period where the autumn volume gain is less than the 2002 to 2013 average, and might have a real terms loss as a causal factor.

But as I show, only one day shows a day on day volume loss.

2) Meaningless.

3) You state in the above comment:
Quote
..if you read my actual words, I'm not saying CH4 caused it directly, only that it happened simultaneously.

Let me make clear what you actually said. Upthread various people were discussing cyclone Nuri. You then said:
Quote
Don't think Nuri is the only one to blame here: Notice the sharp increase in mean CH4, and the subsequent decrease in refreeze (both extent and volume). Also note the sharp fall in 2013 extent and volume, following a 2600 ppb CH4 event last year
From the available evidence it is clear that you were drawing a causal link between the CH4 and ice loss.

4) And there have never been other blips of high methane? The coincidence of two factors once is not proof.


I have made available the volume data you needed to address where the volume loss came from.
http://dosbat.blogspot.co.uk/2013/12/regional-piomas-volume-data.html
Rather than use this resource you choose to launch a barrage of insults against me. Insults I can take, but your laziness in doing the ground work for your own theory means I have to make time available to do your work, that I find very annoying.

So here it is.

Using the regional breakdown of daily PIOMAS gridded data here is the daily difference between 6th and 7th of November, in km^3.

Other   0.001
Okhotsk   -0.105
Bering   0.180
Beaufort   11.060
Chukchi   -7.784
ESS   1.846
Laptev   -9.457
Kara   -34.590
Barents   0.741
Greenland   2.550
Central   8.091
CAA   10.474
Baffin   8.826
Hudson   3.451

Most of the drop comes from Kara, at which point you're probably jumping up and down saying 'Yes I was right, it is methane!!!!' and then you'd stop.

Knowing that NCEP/NCAR data is used to drive PIOMAS I look at NCEP/NCAR data for 7th November.



And I find a warm tongue of air that is indeed warmer than freezing thus makes actual melting possible. So I have identified that export and melt through Fram or Bering is not at play, and that actual melting was involved.

Had you got this far you'd have stopped, being satisfied that the warming was due to methane. I dig deeper, because I have had my own fingers burnt before by jumping to conclusions (which doesn't guarantee that won't happen again!).

I look at that tongue of warming over Kara and immediately suspect a dipole. So I look at pressure.



And yes indeed, we see a strong dipole with high pressure over western Siberia and a low over Barents, that draws in warmer air from outside the Arctic and is a reasonable candidate as the main cause of the volume loss that is the only day to day November volume loss in the PIOMAS data record.

The irony of it all is that had you approached my list in a constructive manner, even being humble enough to ask for help, I'd have gladly given such help to the best of my meagre amateur abilities. Asking proper professional scientists for help when I need it is one of the techniques I use for learning, and it works. If I approach a scientist with questions, ideally phrased from the point of view of 'how can I sort this out', showing I am not wanting to be spoon-fed but am prepared to work for my knowledge, I have found on every occasion that help has been willingly given. And the scientists I am in regular contact with are pleased to see amateurs with enthusiasm for their work.

But were I to storm in telling them how they're wrong and I'm right, and answering every attempt to guide with beligerence and abuse I would get nowhere.

And nowhere is where you are with me. I have had enough of you. I hope the moderators don't get twitchy with the 'ban button'. Feel free to stick around here, you might learn, both about sea ice and human interaction. But please understand that my patience is now stretched beyond its limit. I have no interest in any interaction with you from now on.

viddaloo

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Re: Arctic Refreeze Discussion: 2014/2015
« Reply #89 on: November 12, 2014, 08:34:01 PM »
[Snip]

This is Neven chiming in: viddaloo, you need to read up on what an argumentum ad hominem is. It is when something says you're wrong because you're ugly, or because you travel by train, or because you work for the GWPF. Nobody has done this here. Everyone has explained why your theory is most probably wrong.

You don't like their wording (fart near a melt pond)? IT'S THE INTERNET! People aren't necessarily nice. You can't posit an extraordinary claim, and when people explain to you that there is no extraordinary evidence (because there isn't), accuse them of attacking you personally. It's childish and stifles all discussion.

When someone disagrees with you, he/she is not automatically using ad hominems to attack you. I've known everyone who has responded to you for years, and they're all courteous, intelligent people I highly respect. In other words, you're out of line. And it's the second time this happened.

There's room for almost everything here, except for this. I don't want to see it happen a third time.
« Last Edit: November 12, 2014, 09:49:35 PM by Neven »
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Peter Ellis

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Re: Arctic Refreeze Discussion: 2014/2015
« Reply #90 on: November 13, 2014, 01:06:44 AM »
That really wasn't intended to be rude.  I often find that the sheer scale of the numbers involved in the Arctic makes things hard to intuit, so I find that kind of "downscaling" thought experiment incredibly useful as a sanity check for "Is what I'm saying remotely physically plausible?"

To bring the methane scenario down to a common-or-garden day-to-day understandable scale, I needed an example of small scale localised methane release, and really only one candidate mechanism came to mind :-)

In a similar "downscaling" exercise, around the time of the Tohoku tsunami, I remember calculating that the relative thickness of sea ice compared to ocean depth is about the same as gluing Pringles to a cat - from which we can conclude that while ice may have a dampening effect on sea surface waves, it's not going to have any effect whatsoever to dampen tsunami waves that involve the whole water column

Rubikscube

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Re: Arctic Refreeze Discussion: 2014/2015
« Reply #91 on: November 13, 2014, 02:02:44 AM »
Delta maps for the 10th of November reveals that the refreeze in eastern ESS appears rather slow this year, the same also seems to be the case in Baffin. Though, as one might expect, Barents/Kara is still quite a bit ahead of most years (I'm amazed by how much 2012 refreeze was postponed in this region, didn't remember it was that bad).

The forth year of comparison this week is 2008 (in addition to 2007, 2012 and 2013 respectively). A year which in general saw abnormally much SIA and SIE around this date.

Atomant

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Re: Arctic Refreeze Discussion: 2014/2015
« Reply #92 on: November 13, 2014, 12:19:56 PM »


It is not a personal attack.  It *is* a reaction to persistent misinterpretation of facts and events. You ask a lot of good questions, and make some good connections.  Other times, even in the face of pretty clear evidence that undermines an assertion you make, you persist in digging yourself in deeper.

That's what I'm reacting to.

I assure you, you are getting nothing like what I'd deliver in "full personal attack mode".  It has been known to blister paint (never in this venue), and reserve it for those who truly deserve it.  You're not on that list.

;)

Best regards...

Well, I think you're dismissing and underestimating CH4 in the Polar atmosphere

CH4 can, and does hang around the Arctic atmosphere throughout the winter, and only with the return of sunlight does some CH4 'washed' away. Hydroxyl radicals get to work with UV and as a result of this process Noctilucent Clouds make their appearance from May. Of course other chemicals result from the process but to prove how certain I am about CH4 and  NLC's, I will predict here and now, based on the CH4 readings we're seeing, that 2015 will bring another spectacular show, more intense (and perhaps for longer) that 2014. :)

jdallen

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Re: Arctic Refreeze Discussion: 2014/2015
« Reply #93 on: November 13, 2014, 07:49:10 PM »

Well, I think you're dismissing and underestimating CH4 in the Polar atmosphere

CH4 can, and does hang around the Arctic atmosphere throughout the winter, and only with the return of sunlight does some CH4 'washed' away. Hydroxyl radicals get to work with UV and as a result of this process Noctilucent Clouds make their appearance from May. Of course other chemicals result from the process but to prove how certain I am about CH4 and  NLC's, I will predict here and now, based on the CH4 readings we're seeing, that 2015 will bring another spectacular show, more intense (and perhaps for longer) that 2014. :)
A not unreasonable challenge, which can be evaluated.

So, key factors to examine..

Starting CH4 and distribution
Modified CH4 and distribution

Challenges to getting apples-to-apples includes
- Differences in heat input
   - inflow via weather
   - humidity changes
   - thermal transfer from the ocean
   - insolation input (or lack thereof)

Key elements to capture
- heat transfer between layers of atmosphere
- heat exiting the troposphere
- heat exiting the stratosphere

These would need to be normalized for the differences in heat input.

I'd say there's probably an even dozen scientific papers waiting to be written in that list...
« Last Edit: November 13, 2014, 07:55:15 PM by jdallen »
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viddaloo

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Re: Arctic Refreeze Discussion: 2014/2015
« Reply #94 on: November 14, 2014, 01:05:19 PM »
So, key factors to examine..

Starting CH4 and distribution
Modified CH4 and distribution

Challenges to getting apples-to-apples includes
- Differences in heat input
   - inflow via weather
   - humidity changes
   - thermal transfer from the ocean
   - insolation input (or lack thereof)

Key elements to capture
- heat transfer between layers of atmosphere
- heat exiting the troposphere
- heat exiting the stratosphere

These would need to be normalized for the differences in heat input.

I'd say there's probably an even dozen scientific papers waiting to be written in that list...

Cool! I'll go ahead and do that work plus write those scientific papers (seems quicker and easier, anyway, than explaining to certain people what a "common cause" means and not means).

A happens. B and C follows from A. <-- This does *NOT* mean C follows from B. Only that B and C appeared at the same time.

In other words: I'm not saying what you all think I'm saying. I'm not as stupid as I would be if I was saying what you all think I was saying. Because I never said that, I'm smarter than stupid.

(I know, you were in a hurry and read it wrong and you don't feel like going back to reread because you've decided I'm stupid and said that anyway. Feel free to go on thinking about me as stupid and correcting stupid things I did *NOT* say.)

PS: I guess *I* should apologize. Because the social world is not a logical place.
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viddaloo

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Re: Arctic Refreeze Discussion: 2014/2015
« Reply #95 on: November 14, 2014, 01:20:20 PM »
«1) November? One Day melt? Was this really melt?»

Yes, November is a month, the 11th in the year, yet I can see the need for even questioning this, given the level of taboo here. And yes, there was melt one day. Yes, really melt.
How do you know?  What is your evidence?

Well, Chris confirmed (eventually) that there was a melt.

What you've posted so far is PIOMAS figures.  PIOMAS is a an estimate of what a computer program believes the volume to be, based on numerical modelling, and informed by satellite measurements of area and extent.  It is not actual data on volume.

How do you suggest I get actual data on volume, Peter Ellis?
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viddaloo

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Re: Arctic Refreeze Discussion: 2014/2015
« Reply #96 on: November 14, 2014, 01:40:57 PM »
Most of the drop comes from Kara, at which point you're probably jumping up and down saying 'Yes I was right, it is methane!!!!' and then you'd stop.

No. I don't care where in the Arctic the November 2013 melt was. I just said there was a one–day melt in the totals. I don't have to know where that melt was to know that there was a one–day melt. Finding where that was was your idea, and thus you felt you had to do your own work for yourself.

People mostly think of CH4 and ice–loss as a one–way street: Ice melts, and CH4 is released from hydrates. As already pointed out, it can go the other way. Hydrate thaws will release potent greenhouse gases like CH4 and CO2, and these *will* warm the Arctic Ocean area — probably CO2 more than CH4, at least in Winter. In a few rare examples we've had midwinter volume setbacks — melts — and finding the cause of these is *interesting*.

In no way does that mean one should be «jumping up and down saying 'Yes I was right, it is methane!!!!'». But finding the CH4 levels around those events is key to understanding whether hydrates were melted because of ice–loss or the other way around (or, of course, if other causes were more likely, eg storms, heatwaves).
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jdallen

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Re: Arctic Refreeze Discussion: 2014/2015
« Reply #97 on: November 14, 2014, 06:22:37 PM »
Viddaloo;

You cut off the top of my quote, which was..
Quote
A not unreasonable challenge, which can be evaluated.
The rest is a highly abbreviated list of requirements which not just you, but any researcher would need to address in order to support the assertion it appeared you were making - that prompt increases of CH4 have an immediate visible effect on Arctic Sea ice via changes in heat transfer.

It perhaps would benefit us to reflect briefly on two facets of argument here.

First is burden of proof. When drawing a conclusion, the quality of your conclusion is directly related to the quality and reliability of your supporting evidence.

Second is Hitchen's Razor - what is asserted without evidence can be dismissed without evidence.

Guided by these, it is pretty clear what you were doing was speculating about the impact of CH4.  Where you went off the rails and found yourself being challenged was when you tried to use that speculation as the foundation for further argument.

It is fine, actually encouraged, for people to speculate here. That mechanism leads us to all sorts of interesting avenues of investigation and understandings. Where you will draw criticism here (as most of us have on occasion) is when you let your arguments get ahead of fact. That includes persisting in defending speculation in view of fact which provides reasonable, supportable counter to that speculation. 

Counter fact in an argument does not preclude a hypothesis. Rather it sets the bar which must be reached in order to support it.  I just gave you a list you could use to prove yours.
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ChrisReynolds

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Re: Arctic Refreeze Discussion: 2014/2015
« Reply #98 on: November 14, 2014, 06:32:18 PM »
«1) November? One Day melt? Was this really melt?»

Yes, November is a month, the 11th in the year, yet I can see the need for even questioning this, given the level of taboo here. And yes, there was melt one day. Yes, really melt.
How do you know?  What is your evidence?

Well, Chris confirmed (eventually) that there was a melt.

In the interests of accuracy. I did the work you couldn't be bothered to do, so don't go crowing over others about your inadequacies.

Absolutely unbelievable.  ::)

viddaloo

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Re: Arctic Refreeze Discussion: 2014/2015
« Reply #99 on: November 14, 2014, 06:43:53 PM »
«1) November? One Day melt? Was this really melt?»

Yes, November is a month, the 11th in the year, yet I can see the need for even questioning this, given the level of taboo here. And yes, there was melt one day. Yes, really melt.
How do you know?  What is your evidence?

Well, Chris confirmed (eventually) that there was a melt.

In the interests of accuracy. I did the work you couldn't be bothered to do, so don't go crowing over others about your inadequacies.

Absolutely unbelievable.  ::)

I'm not saying you confirming it amounts to evidence, Chris. The good Peter Ellis here rejects PIOMAS as actual data, and what I did was to look for volume reductions in the (whole Arctic) PIOMAS data, before you went ahead and did exactly the same in the regional PIOMAS data.

For a guy who rejects PIOMAS altogether as not actual data, this isn't good enough, but I figured «appeal to authority» might work in this case (your name rather than what you're saying).

As we all know, you don't have to go to the regional data to prove there was overall net melt from a day to the next. That is absolutely redundant, but no–one can stop you from doing it, of course.
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