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Messages - weatherdude88

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1
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: June 24, 2019, 02:09:53 PM »
UH AMSR2 data is showing more high latitude sea ice extent and area in the arctic basin, than the highest melt years.


UH AMSR2 CAB extent


UH AMSR2 CAB area

2
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: June 24, 2019, 01:58:28 PM »
Looking at the raw daily data, 2019 NSIDC sea ice area is now the fifth lowest value in the data set. For 6.23, the daily value is 7,787,023 kilometers squared. There was a loss of 102,855 kilometers squared from the previous date.

2019 now has 236,390 kilometers squared more than 2012, 32,029 kilometers squared more than 2010, 9,356 kilometers squared more than 2007, and 8,144 more than 2016.

edit: gerontocrat was able to answer my question on the Central Arctic sea disparity for the sub 2008 data set. For my posts on 2007 sea ice area, I should of been adding 310,000 kilometers squared to the final value when all seas had been added for the pole hole adjustment.

3
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: June 24, 2019, 03:36:40 AM »
Looking at the raw daily data, 2019 NSIDC sea ice area is the fourth lowest value in the data set. For 6.22, the daily value is 7,889,878 kilometers squared. There was a loss of 82,849 kilometers squared from the previous date.

2019 now has 293,437 kilometers squared more sea ice area than 2007, 259,734 kilometers squared more than 2012, 4,313 kilometers squared more than 2016. Losses continue to be below average.

The next closest year is 2010, which has a 36,358 kilometers squared lead.
If the sea ice area loss for 6.23 is less than 110,999 kilometers squared, 2019 will have the 5th lowest daily value for 6.23.

The highest melt years had significant late June area cliffs, where 2019 has had a period of below average sea ice area losses.

Why does NSIDC Central Arctic sea ice area data, show less sea ice area for the sub 2008 data set than the post 2007 data set? The data set shows 2019 has 471,675 kilometers squared more sea ice area in the CA than 2007. The only logical explanation is NSIDC redrew the sea boundaries for the post 2007 data?

4
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: June 21, 2019, 03:24:31 PM »
Looking at the raw daily data, 2019 NSIDC sea ice area is still the third lowest value in the data set. For 6.20, the daily value is 8,039,945 kilometers squared. There was a loss of 67,579 kilometers squared from the previous date.

2019 now has 142,879 kilometers squared more of sea ice area than 2007, and 264,543 kilometers squared more than 2012. Losses continue to be below average.

The next closest year is 2016, which has a 66,540 kilometers squared lead.

NSIDC sea ice extent is now the 5th lowest for 6.20, with a value of 10.427 millions of kilometers squared. 2019 has greater sea ice extent for the date, than 2010, 2011, 2012, and 2016.

5
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: June 20, 2019, 09:33:33 PM »
NSIDC Total Area as at 19 June 2019 (5 day trailing average) 8,136,524  km2
               
Total Area         
 8,136,524    km2      
-273,462    km2   <   2010's average.
-419,855    k   <   2018
-938,256    k   <   2000's average.
         
Area loss 66 k, 43 K LESS than the 2010's average loss of 109 k on this day.
Total area 2nd lowest (again) (16 k less than 2016, and 263 k greater than 2012).
2012 is still the front runner as regards area now.

Looking at the raw daily data, 2019 is now in third place with respect to sea ice area. For 6.19, NSIDC sea ice area has a daily value of 8,107,524 kilometers squared.

2019 now has more than 57,800 square kilometers of sea ice area than 2007, and 263,273 square kilometers more than 2012.

6
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: June 18, 2019, 04:44:28 PM »
NSIDC sea ice extent is now the 7th lowest value for 6.17, with a value of 10.696 millions of kilometers squared. 2019 has greater sea ice extent for the date, than 2010, 2011, 2012, 2016, 2017, and 2018.

do you just repeat numbers that we can see ourselves or do you want to tell us something with it ?

extent is not a good measurement at this time of the year IMO, area often drops like a stone while extent is dropping less or growing or vice versa. compaction at times is higher and at times is lower, so what.

if it's raining today or this week one would not suggest a trend towards rainforests. disconnected data depending on the time of the year only produce false impressions, a strategy  that is often used by liars, cheaters, scamsters & deniers.

a long winter in nova scotia made my friend who lives there say: can't see much of any warming, while it's called "global warming", neither canadian nor nova scotian warming LOL

then look at the gain in okhotsk below, it did not happen, no freezing temps around there and wam waters already.

if you want to tell us something, then say it so we can check and/or oppose false assumptions. if you only want to make disconnected buzz-word-statements or stating the obvious, i sooner or later have to see to avoid seeing it ;)

This is a thread for sea ice area and extent data. Should no one post any extent or area data in this thread? You do not seem to have an issue with other data that is posted here.

One could argue NSIDC sea ice extent could be the most important data set we have, due to the historical record to compare apples to apples, and the possibility of area flashing back due to sensors counting melt ponds as open water.

This is the whole purpose of this thread. Perhaps you prefer to see certain data sets, at certain times of the year, based on your subjective point of view?

This is not the time or place for that.


7
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: June 18, 2019, 03:55:59 PM »
NSIDC sea ice extent is now the 7th lowest value for 6.17, with a value of 10.696 millions of kilometers squared. 2019 has greater sea ice extent for the date, than 2010, 2011, 2012, 2016, 2017, and 2018.

8
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: June 15, 2019, 07:46:59 PM »
For 6.14., NSIDC sea ice extent is now in 5th place with a value of 10.842 millions of kilometers squared. 2019 now has greater sea ice extent for the date than 2018, 2016, 2012, and 2010. There have now been 3 straight days of gains in the data set.

One more day of gains, or a loss of less than 27,000 kilometers squared, will put us in seventh place for 6.15.

9
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: June 14, 2019, 09:05:59 PM »
Cyclones dispersing the ice (especially in the Beaufort) also play a role, I think.

Looking at the last 3 days of NSIDC Beaufort sea ice extent and area data, there has been an area increase of 786 kilometers squared, and an extent increase of 449 kilometers squared.

10
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: June 13, 2019, 02:21:27 AM »
I think the confusion stems from the fact that a climate change denier is muddling up the threads with BS representations of how the melt season is progressing, cherry picking the most limited representations and then saying "oh this season is not bad at all". I think Neven should ban him as he is not here in good faith. I have been informed by other posters that he is indeed a denier who posts the same BS at other message boards.

It amazes me how every melting season you predict a new record minimum, and when it does not happen you go silent.

Then when I post some data and claim this season 'will not end up in the bottom 3' you act like a butt hurt baby, since you cannot process any data that does not fall in line with your wish casting of a new record arctic sea ice minimum.

If you used more of your mental capacity on learning, perhaps you would understood the context of the above area conversation, which had nothing to do with my earlier post.

11
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: June 12, 2019, 08:46:47 PM »
I think he is a denier and you are just giving him more air by responding. The graph in the previous post shows we are two weeks ahead of any other year in terms of current core extent.

Area is more telling than extent. For 6.11.2019 NSIDC sea ice area for the (Beaufort + Central Arctic + Chukchi + East Siberian Sea +  Laptev Sea) added together gives us an area of:

2016 5,890,973 square kilometers
2012 5,962,622 square kilometers
2019 5,977,631 square kilometers

2019 is currently in 3rd place for the NSIDC sea ice area.


12
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: June 12, 2019, 07:53:38 PM »
AMSR2 CAB and NSIDC CA ice area look robust. There may be a significant slow down in basin wide losses during July, when the more vulnerable areas of the ice pack have melted out.









 

13
Well then if that is what they say, the current conditions seem to be the opposite of their conclusions.

If you are referring to specific latitudes outside the polar region during northern hemisphere summer, I would concur. However, this is a forum that focuses on the cryosphere, that is indeed located at high latitudes.

14
I'll leave this thread open, for as long as the solar stuff doesn't go in the wrong direction, but given that a link is posted to a paper from 1921, I'm moving it to the Arctic Background category.

Christ! 34 years before I was born. All of the scientists involved in the research are long since dead, I presume.

The most relevant reading to help us determine a proper approach to this research would be...

"The Structure of Scientific Revolutions" by Thomas S. Kuhn

The initial source from the Journal of Geophysical Research is from 2008.

15
I also would note that both of the quotes above are related to winter conditions.  We are now in the melt season so I'm not sure what the rational behind this thread even is 🤔.

Quote
"In both the model and observations, the greatest correlations with the solar cycle during this season are in the Northern (summer) hemisphere."

16
I could not get the first link to open

It opens faster on a desktop browser. Here is another link to the same paper, to access faster on your mobile device.

https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2008JD010114

17
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: June 11, 2019, 09:21:59 PM »
NSIDC Central Arctic sea ice area is now the highest value in the data set for 6.10 with a daily value of 3,093,797 kilometers squared.

Isn't the good area in central arctic caused by the fact ice is deported towards Greenland and Barents seas, filling areas where ice usually melts ?

Sure, there is more ice that is being exported towards the Greenland and Barents seas. However, there is also more ice compacted at higher latitudes that will be difficult to melt as a result of the anticyclonic weather pattern the arctic has been in.

There are multiple different aspects from this weather event. Both positive and negative as it relates to the upcoming minimum. To achieve a historic minimum you need different weather patterns at specific times throughout the melt season, that coincide with different events in the arctic. It is not as simple as we had this weather pattern for x time, so it will only produce this one effect, and we will now hit a record minimum.

18
Let's discuss differences in barometric pressure at polar latitudes, during different stages of the solar cycle.

Quote
"The magnitude of the change in the troposphere is large enough to
alter sea level pressure fields such that a more positive
winter Southern Annual Mode (lower pressure at higher
latitudes) is produced in about 70% of the cases (especially
with climatological and historical SST). The sea level
pressure differences are on the order of 4 mb at high
southern latitudes"

Quote
"This effect, as well as the winter zonal
wind change descending into the troposphere, is more
consistent in the Southern Hemisphere during June –August
then in the Northern Hemisphere for December–February,
most likely owing to the greater planetary wave forcing and
inherent variability during Northern Hemisphere winter"

https://pubs.giss.nasa.gov/docs/2008/2008_Rind_ri07700f.pdf


Page 166 starts "Variations In Air Pressure And In Solar Activity"

https://books.google.com/books?id=yV81i_hopSwC&printsec=frontcover&source=gbs_ge_summary_r&cad=0#v=onepage&q&f=false



19
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: June 11, 2019, 07:02:47 PM »
Is this going to be a record year for sea ice retention dude88 ? b.c.

No, sea ice extent and area values will not be in the bottom 3 for the minimum either. The constant anticyclonic weather pattern has compacted sea ice at high latitudes.

This will become especially evident, as sea ice extent and area losses will stall later this melt season when the lower latitude sea ice has melted out.

It should come as no surprise that this early spring and start of summer has been dominated by anticyclone, considering we are at the start of the solar minimum.

There has been research that concludes during the solar minimum, the summer melting season at polar latitudes ‘barometric pressure is higher’ than during other intervals of the solar cycle.
It appears we will now switch to a regime of low pressure over the arctic. I am skeptical it will last longer than several weeks.

I started a new thread, so we do not continue off topic.

https://forum.arctic-sea-ice.net/index.php/topic,2755.0.html

20
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: June 11, 2019, 06:08:44 PM »
NSIDC Central Arctic sea ice area is now the highest value in the data set for 6.10 with a daily value of 3,093,797 kilometers squared.


21
Arctic sea ice / Re: The 2019 melting season
« on: June 11, 2019, 01:15:08 AM »
Hi res Arctic Basin extent looks as though its heading into uncharted territory.

It still does. What's more Basin area seems poised to do likewise:


Central Arctic Basin area, the most important region for the upcoming sea ice minimum, is breaking away from the post 2012 pack. Just not in the direction most on here thought it would.






22
Arctic sea ice / Re: The 2018/2019 freezing season
« on: September 28, 2018, 08:42:24 PM »
Profuse assumptions are being made. We cannot assume the atmospheric temperature profile under areas of high pressure at 850 MB or 500 MB, will correlate to the surface being as anomalously warm, as it would during northern hemisphere summer.





It is probable, there will be a layer of closer to average temperatures near the surface, than at higher altitudes, due to less solar isolation (less surface heating) and a cooler surface.

I predict northern hemisphere sea ice extent and area will continue to increase, albeit with a slower increase than average. The 850 MB and 500 MB anomalies are not indicative of the actual surface anomaly after northern hemisphere summer.

The decrease in cloud thickness / coverage under high pressure, should also allow for more heat energy to radiate into space. This could also increase the heat anomaly at 850 MB and 500 MB.


23
Arctic sea ice / Re: 2018 sea ice area and extent data
« on: June 29, 2018, 01:44:53 PM »
The NSIDC northern hemisphere arctic sea ice extent value for 6.28.2018 is 10.031 millions of square kilometers. This places 2018 northern hemisphere sea ice extent in 8th place for the date.

ftp://sidads.colorado.edu/DATASETS/NOAA/G02135/seaice_analysis/

24
Arctic sea ice / Re: 2018 sea ice area and extent data
« on: June 27, 2018, 01:46:00 PM »
The NSIDC northern hemisphere arctic sea ice extent value for 6.26.2018 is 10.297 millions of square kilometers (gain of 56 thousand square kilometers). This places 2018 northern hemisphere sea ice extent in 8th place for the date.

25
Arctic sea ice / Re: 2018 sea ice area and extent data
« on: June 26, 2018, 06:54:16 PM »
The NSIDC northern hemisphere arctic sea ice extent value for 6.25.2018 is 10.241 millions of square kilometers. This places 2018 northern hemisphere sea ice extent in 7th place for the date.

ftp://sidads.colorado.edu/DATASETS/NOAA/G02135/seaice_analysis/

26
Arctic sea ice / Re: The 2017 freezing season
« on: August 29, 2017, 01:52:04 PM »
NSIDC northern hemisphere sea ice extent had another uptick today. we are now 102000 Kilometers squared above 8.25.2017. 8.28.2017 is now the highest value in the last 5 days.

27
Arctic sea ice / Re: The 2017 freezing season
« on: August 28, 2017, 01:36:11 PM »
Our first candidate for NSIDC arctic sea ice extent minimum is 8.25.2017. The NSIDC arctic sea ice extent metric is up 92 thousand Kilometers squared the past two days. The JAXA sea ice extent metric also recorded an increase today. 

ftp://sidads.colorado.edu/DATASETS/NOAA/G02135/north/daily/data/N_seaice_extent_daily_v2.1.csv

28
Arctic sea ice / Re: IJIS
« on: August 21, 2017, 05:04:03 PM »
We are currently in an unprecedented slow down in this melting season. Looking at JAXA sea ice extent data for the past 5 days (8.14-8.20), here is how this year compares to previous years. All of this in a time frame were weather was considered unfavorable by some. Where is the heat? 




78499  Kilometers Squared (2017)    
250806 Kilometers Squared (2016)
271380 Kilometers Squared (2015)    
201212 Kilometers Squared (2014)
170241 Kilometers Squared (2013)
323143 Kilometers Squared (2012)    
214782 Kilometers Squared (2011)    
171913 Kilometers Squared (2010)    
242082 Kilometers Squared (2009)    
235464 Kilometers Squared (2008)
209292 Kilometers Squared (2007)    
236247 Kilometers Squared (2006)    
174575 Kilometers Squared (2005)    
294866 Kilometers Squared (2004)    
125356 Kilometers Squared (2003)    
223099 Kilometers Squared (2002)    
207152 Kilometers Squared (2000's Average)
141827 Kilometers Squared (1990's Average)    
106000 Kilometers Squared (1980's Average)

29
Arctic sea ice / Re: The 2017 melting season
« on: August 15, 2017, 06:14:21 PM »

Neven wrote in his post that we dodged a cannonball this year, which I agree. But this luck can't go on forever, sooner or later we'll get a brutally bad melting season.

I would argue the arctic got hit by Curlin's Proverbial "cannonball" this past winter. So if we had below average winter temperatures, with above average summer temperatures, would we have dodged the "cannonball"? I hypothesize the warm winter temperatures and their corresponding cooler summers over the last decade are a result of the same mechanisms. Weather patterns do not get stuck months let alone a year at a time. Classifying this as "luck" is nothing more than wishful thinking.

30
Arctic sea ice / Re: Home brew AMSR2 extent & area calculation
« on: August 15, 2017, 05:16:21 AM »
Significant area gains today (50K+). Extent looks to be a wash.


31
June I went for 2.75-3.25. then I wimped out and went up to 3.00-3.50 for July. As we reach the end of August voting I am going back to my original vote. 2.75-3.35 at the end of the day the facts still remain that the year started with very thin ice. There is still time for a huge area to go from being fractured spread out ice to being open water. Everything left to play for. MASIE has been lower than 2012 right up until a few weeks back then it went high but only a few 100 thousand sq km. Now that has all gone again and 2017 is back in the lead.

2006-6914858.83 Kilometers Squared
2007-5658628.48 Kilometers Squared
2008-6957847.31 Kilometers Squared
2009-6649893.15 Kilometers Squared
2010-6326294.13 Kilometers Squared
2011-6230654.16 Kilometers Squared
2012-6308909.23 Kilometers Squared
2013-6528327.55 Kilometers Squared
2014-6815819.12 Kilometers Squared
2015-6446197.31 Kilometers Squared
2016-6335948.88 Kilometers Squared
2017-6301329.71 Kilometers Squared

For day 221 (day 222 will update today), the MASIE value is currently third place (ahead of 2007 and 2011).

ftp://sidads.colorado.edu/DATASETS/NOAA/G02186/masie_4km_allyears_extent_sqkm.csv

I find your illogical reasoning for a record JAXA sea ice extent minimum value using MASIE data underwhelming.



32
Arctic sea ice / Re: The 2017 melting season
« on: August 10, 2017, 05:09:17 PM »
From Extent Numbers and arctic.io images, the Trend seems to be that Ice is being dispersed by the Storms, thus keeping Extent Decline (relatively) lower, than expected.
But Jetstream Collapse & crossing the Equator plus Extreme Summer Events should give us the whole Picture about the State of the Ice (Slush).

Quite the Contrary.


33
The rest / Re: Do you understand the Enthalpy of Fusion of ice?
« on: September 15, 2016, 07:42:08 PM »
Since we are discussing the Enthalpy of Fusion, it is only fair we also discuss the Mpemba effect. Warm/hot water under certain conditions freezes faster than colder water.


34
Arctic sea ice / Re: 2016 sea ice area and extent data
« on: September 14, 2016, 03:00:31 PM »
I was aware of the 5 day trailing mean, however unaware it was used for the NSIDC minimum northern hemisphere sea ice extent value. It appears NSIDC does calculate their minimum/maximum values form a 5 day trailing mean. My apologies BornFromTheVoid, I  am expecting NSIDC to shortly release a press release with a minimum of  4.14*10^6 KM^2.

35
Arctic sea ice / Re: 2016 sea ice area and extent data
« on: September 14, 2016, 12:59:06 AM »
5 day NSIDC extent crept upward by 2k yesterday, so the likely minimum will be 4.137 million km2 from September 10th.

The NSIDC northern hemisphere sea ice extent minimum was September 7th, 2016 with a value of 4.083*10^6 KM^2.

ftp://sidads.colorado.edu/DATASETS/NOAA/G02135/north/daily/data/NH_seaice_extent_nrt_v2.csv

The 4.137 million KM^2 value was on September 9th, 2016. 4.083 is less than 4.137, and September 7th is before September 9th. Therefore the minimum was on the 7th.


36
Seems like many competing effects.  And thus anyone who proclaims the result is obvious, without citing precedent over a range of similar predicates, is claiming more knowledge than I would be willing to trust.

One thing it shows pretty clearly is that we have no SST's currently across the central arctic below -5C.  That indicates pretty definitively that the transfer of heat is not yet high enough to support a refreeze. 

My -5C claim is in part historical, in part from work presented elsewhere by others on these forums, and actually is shaded on the conservative side.  I've read from others here that the threshold may actually be a bit lower, at -10C. 

No need to be conservative because we have never had liquid water surface temps across the arctic at -5C as suggested by your first post. The initial map posted shows a large area of uniform 2 meter surface temperatures.

37
Arctic sea ice / Re: Home brew AMSR2 extent & area calculation
« on: August 24, 2016, 09:29:33 PM »
Find an Arctic SST map from September/October with -5 Celsius water temperature. Better yet find any map where there is arctic sea water at -5 Celsius or even an example in nature. You might be looking for a while since it does not exist.
OK, this is exactly what I was talking about  - a Troll. 

You are trying to imply that I was suggesting water wouldn't freeze at -5C or -10C.  Nonsense.  That's nothing like what I was saying.

You appear to be posting this to accomplish two things (1) distract the audience by attacking my credibility and (2) disrupt the discussion.

Just stop.

Show me any example where the liquid water temperature in the arctic is -5 Celcius?

My -5C claim is in part historical, in part from work presented elsewhere by others on these forums, and actually is shaded on the conservative side.  I've read from others here that the threshold may actually be a bit lower, at -10C. 

Show me this historical claim. Perhaps rather than continuous ad-hominems, you can address with an example or provide some scientific evidence? 

One thing it shows pretty clearly is that we have no SST's currently across the central arctic below -5C.  That indicates pretty definitively that the transfer of heat is not yet high enough to support a refreeze. 

We have never had liquid water surface temps across the arctic at -5C.


38
Arctic sea ice / Re: Home brew AMSR2 extent & area calculation
« on: August 24, 2016, 09:20:25 PM »
y, would not mean new ice, would mean melt pond freeze. Very normal on this time in the year.

Melt pond freeze over contributes to an increase in area. The argument here is "is CAB area increasing?" I am not going to get into an argument based on how much of the CAB increase is melt pond freeze over VS. new sea ice formation. These regions received significant increases the last several days based on AMSR2 from U Bremen sea ice concentration map images.

39
Arctic sea ice / Re: Home brew AMSR2 extent & area calculation
« on: August 24, 2016, 09:02:57 PM »
If so, then there was refreeze of melt ponds on the site to greenland, or what area do you mean?

The coldest regions of the arctic ocean had an extended period of anomalous cold surface temperatures based on the long term mean which is already well below freezing for 80 north and above. Here are the last three AMSR2 from U Bremen sea ice concentration map images. Look near the pole where we had anomalies. There is a significant increase in ice concentration in the last two days in this region.










40
Arctic sea ice / Re: Home brew AMSR2 extent & area calculation
« on: August 24, 2016, 08:40:51 PM »
@ weatherdude88

You make it to simple, you have to look where it was cold, not only if its be cold enough, here the past 7 days resolution anomaly: http://www.karstenhaustein.com/reanalysis/gfs0p5/ANOM2m_arctic/ANOM2m_past07_arctic.html

the cold was on the side, where ice is not open and already frozen, also is to note, that winds are also play a role by refreeze and we saw often very middle to strong winds, so therefore between the ice should be small ekman-pumping

Therefore its seem very unlikly that there was any kind of refreeze

You are proving my point. Go back and look at the sea ice area concentration maps. Some of those areas with the coldest anomalies saw an increase in concentration. Additionally, these anomalies are based on the long term mean.

41
Arctic sea ice / Re: Home brew AMSR2 extent & area calculation
« on: August 24, 2016, 08:35:32 PM »
My -5C claim is in part historical, in part from work presented elsewhere by others on these forums, and actually is shaded on the conservative side.  I've read from others here that the threshold may actually be a bit lower, at -10C.  However, I will do some additional research on it specifically.

Find an Arctic SST map from September/October with -5 Celsius water temperature. Better yet find any map where there is arctic sea water at -5 Celsius or even an example in nature. You might be looking for a while since it does not exist.

42
Arctic sea ice / Re: Home brew AMSR2 extent & area calculation
« on: August 24, 2016, 08:03:05 PM »
AMSR2 will "flip" on a daily basis.  It fails mightily when used to assert massive changes - melt or freeze - have taken place on a day to day basis.  Its best and effective use it over longer time scales. Using it as you have, you are indulging your confirmation bias and doing bad science.
 

Update 20160820.
Regional area in the CAB increased: +31k. The Laptev regions went the other way: -23k.

Update 20160821.
Same for CAB area: +63k.

The CAB area has been increasing for a number of days now according to the Home brew AMSR2 extent & area calculation. So anomalously cold below freezing temperatures at the surface for an extended period at 80 degrees north cannot cause a several day freeze up? The adjacent water that is near its freezing point cannot have a small amount of heat removed to form ice? Why do the other regions show losses under similar weather conditions? The scenario of a temporary refreezes or clouds causing false losses are more logical than false gains. This is the scenario that makes the most sense using thermodynamics/physics.


 
As one example, consider the attached DMI 2 meter temperature map for today below.  One thing it shows pretty clearly is that we have no SST's
2 meter temperature anomaly maps are for surface temperatures and are indeed not SST's.

At a fundamental level, your posts fail to demonstrate a cogent understanding at the forces in play. 

As one example, consider the attached DMI 2 meter temperature map for today below.  One thing it shows pretty clearly is that we have no SST's currently across the central arctic below -5C. 

It is well known arctic sea water freezes at around -1.8 Celsius. (Yes, this changes with salt concentration) If SST’s were -5C we would have ice at the surface. (not arctic sea water) Please elaborate on your -5 SST Celsius claim.

43
I really don't know how to get through to you. The increase is measured from AMSR2 which does not account for all clouds.

Comparing MODIS today and yesterday clearly shows why there was a sudden apparent increase in area across the CAB. Clouds increased dramatically.

I am telling you the clouds are the reason the area increased and you are telling me the area increased... you are just full of non-sequiturs today!

Update 20160820.
Regional area in the CAB increased: +31k. The Laptev regions went the other way: -23k.

Update 20160821.
Same for CAB area: +63k.

CAB area has been increasing for several days now according to the Home brew AMSR2 extent & area calculation. When did the cloud cover dramatically increase? In your above post you claim a dramatic increase comparing today and yesterday? Disregarding, comparing day to day images the cloud cover does not vary much.

https://lance.modaps.eosdis.nasa.gov/imagery/subsets/?mosaic=Arctic.2016236.terra.4km

I am still also trying to understand why we are not experiencing the same "bbr2314 phenomenon" in the other regions with similar cloud cover?


44
The CAB isn't increasing in area.

Regional area increased in the CAB : +53k. Area declined in Laptev (-26), Chukchi (-18k) and ESS (-16k).

In layman's, if the CAB really is decreasing and the satellites are "tricked" by cloud cover, why are we not seeing this same phenomenon the last several days in the above regions where there is currently the same or thicker cloud cover?


45
I would argue that cloud cover has more of an impact the less sea ice we have, but this becomes especially pronounced as area decreases relative to extent (i.e., as compactness goes down).

Consider; in 2012, things were bad, but the main pack was still cohesive. Whether or not this area was covered by clouds, it appeared entirely (or almost entirely) white to the satellites, with the uniformity in concentration aiding "steadiness" in observations. Cloud cover over open ocean is easier to reduce than cloud cover over a background that is the same color.

This year, with structure of the pack completely shattered, you have -- for the very first time -- only a small area of ice that is structurally intact. While this small triangle of area N of the CAA/Greenland falls into the same category as 2012's ice, the remainder most certainly does not.

With ice that is very dispersed, as in this year, cloud cover -- especially of the low sort -- masks much of the open water in between the ice, and the satellites have a much harder time distinguishing what is real vs. what isn't, at least when clouds are overhead. Additionally, I think open water *encourages* cloud cover this far N, especially as it gives up its latent heat from the summertime, further reducing accuracy as clouds have been nearly continuous over much of the Arctic this summer.

Again, the key is the overall structural integrity of the ice.

Updates of 2012 AMSR2 data seem to have been completed. We have complete data from the first of August to 30th September. Thanks for that.

Update 20160823.

Extent: -81.4 (-123k vs 2015, -733k vs 2014, -706k vs 2013, +784k vs 2012)
Area: -8.3 (-296k vs 2015, -976k vs 2014, -946k vs 2013, +484k vs 2012)
 
You will find the updated graphs in the top post

Regional extent declined in the CAB (-32k) and Laptev (-19k).

Regional area increased in the CAB : +53k. Area declined in Laptev (-26), Chukchi (-18k) and ESS (-16k).

The attached delta map is of the Beaufort-Chukchi-ESS corner. Lots of reds and blues confirm there is a lot of ice moving around. The detachment of the Wrangek ice progresses further.

bbr2314,

Please explain why the CAB is increasing in area, whereas the ESS and Chukchi lost area. Are you hypothesizing the ice is in better shape in these region than the CAB? (Or is there even any ice there if it is in worse shape?) Additionally, with the storminess on the Russian side surely there is thicker cloud cover currently in the Laptev. So why does the Laptev also show loses? Please help me understand your "theory" works with respect to the above regions?

46
Arctic sea ice / Re: Home brew AMSR2 extent & area calculation
« on: August 24, 2016, 03:45:43 PM »
Regardless,  AMSR2 from U Bremen sea ice concentration map shows a significant gain in ice area in the CAB. Our cyclone is long gone from the Canadian side of the arctic. 




47
Arctic sea ice / Re: Home brew AMSR2 extent & area calculation
« on: August 24, 2016, 01:27:34 AM »
MODIS shows an inordinate amount of very thick clouds today. Once those clear I would think the CAB flashes back to major red and we have a "false" drop of 150K+ to account for the "gains" that weren't really there.

Quote
A key feature of these AMSR instruments is the ability to see through clouds, thereby providing an uninterrupted view of ocean measurements

http://www.remss.com/missions/amsr

Please provide scientific evidence on where AMSR instruments show "false gains" due  to cloud cover to support your claim. If you do not provide any, most in this forum including myself will conclude this is another Dunning-Kruger-Esque statement.

If you ever followed concentration maps closely than you would have noticed plently of false sea ice detection.

Today there is ice detected in the Sea of Okhotsk and around northern Japan. These areas are probably masked out in August, but false detection remains in the Arctic basin.

Its possible that there are plenty of ice crystals in the clouds, but defenitly none in the sea.

Quote
this approach only detects the first appearance of open water so potential refill of ice is not accounted for.


Quote
Conversely, the better agreement with AMSR-E and IMS compared to QuikSCAT and IMS is likely due to the reduced sensitivity to transient weather events that can affect QuikSCAT (Howell et al., 2010 and Yu et al., 2009).

http://www.sciencedirect.com/science/article/pii/S0034425714000649

At variance with:

Quote
False ice concentrations can occur due to bad weather systems.

http://www.iup.uni-bremen.de:8084/amsr2/regions-amsr2.php

However, if we take a look at the other sea ice area models, and when we experienced moderate to strong loses the first several days of cyclonic weather, why did ASMR instruments not show "false gains"? Even though we had anomalously cold weather with snowfall? Why do the other sea ice metrics correlate closely with ASMR2 even though they use different algorithms?

Speak for yourself Weatherdude, and the others will speak for themselves. I could be wrong, but I think most will disagree with you.

Why would ASMR instruments show a 87.7 thousand square kilometers gain over 2 days with similar atmospheric conditions to the previous several days? It seems more likely from a scientific point of view that "false loses" were reality when areas were refreezing.   

I am still waiting for scientific proof that ASMR instruments show large scale "false gains" over multiple days above 70 degrees north.


48
Arctic sea ice / Re: Home brew AMSR2 extent & area calculation
« on: August 23, 2016, 11:24:10 PM »
MODIS shows an inordinate amount of very thick clouds today. Once those clear I would think the CAB flashes back to major red and we have a "false" drop of 150K+ to account for the "gains" that weren't really there.

Quote
A key feature of these AMSR instruments is the ability to see through clouds, thereby providing an uninterrupted view of ocean measurements

http://www.remss.com/missions/amsr

Please provide scientific evidence on where AMSR instruments show "false gains" due  to cloud cover to support your claim. If you do not provide any, most in this forum including myself will conclude this is another Dunning-Kruger-Esque statement.

49
Arctic sea ice / Re: The 2016 melting season
« on: August 16, 2016, 01:01:22 AM »
Plot the same graph from each source if you want to show differences, not one thing from DMI and something different from PIOMAS.

I'll leave that as an exercise for the interested reader. FTB for example?

Jim, thank you for your presentation of the US Navy HYCOM/CICE implementation against the DMI HYCOM/CICE presentation. It seems to me that in this particular case (2016 versus 2012) the US Navy HYCOM/CICE model is consistent with PIOMAS and Cryosat 2 observations, and DMI is NOT.

For example, as early as June 23, DMI still showed 3 - 4 meter ice in the Pacific section of the CAB :


None of the other ice volume product (US Navy HYCOM/CICE nor PIOMAS nor Cryosat 2) show that thick ice in that area.
 
And may I add that Richard Rathbone provides only unfounded criticism of your work, and fails to provide ANY evidence in this comparison.

PIOMAS clearly shows thicker ice than 2010,2011,2012, and 2013.



Since the last PIOMAS update was in July and weather conditions have remained favorable for slower than average ice melt, it is no surprise DMI's updated sea ice thickness shows thicker ice than 2012. (Keep in mind, in 2012 the GAC already did most of its damage in relationship to ice volume as demonstrated by the various papers posted here). Furthermore, DMI's sea ice thickness model is based on HYCOM-CICE. Lastly, your posted graph is from 2015.

50
Arctic sea ice / Re: The 2016 melting season
« on: August 12, 2016, 05:02:09 PM »
Temperatures remain anomalously cold in the arctic.
...
The upcoming storm will serve to reinforce/intensify these anomalies. A fifth place finish in sea ice extent is looking likely, with an early minimum.
...

Considering your assessment same time last year using the 925 hpa plots, when you predicted a "significant slowdown" that might lead 2015 be above 2013 and 2014,

http://forum.arctic-sea-ice.net/index.php/topic,1149.msg59717.html#msg59717

I should put all my chips this year finish record low.

might

Quote
The rapid pace of daily ice loss seen in late July 2015 slowed somewhat in August.
http://nsidc.org/arcticseaicenews/2015/09/steady-decline-summer-minimum-approaching/

Considering members here were predicting 2015 would beat 2012 I rest my case. Seaicesailor, how about you make a prediction we can judge your accuracy? (We can see who is closer and we will find out in 45 days or less) The anomalously cold weather, cloud cover, and physical forces of low pressure with regards to ice dispersion will be extremely favorable for ice preservation. 2012 featured anomalously warm weather leading up to and following the storm. (This is nothing like the 2012 GAC)

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