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Messages - Juan C. García

Pages: 1 ... 35 36 [37] 38 39
1801
Arctic sea ice / Re: 2016 sea ice area and extent data
« on: April 03, 2016, 02:47:06 AM »
Leap years (like 2004, 2008 and 2012) have an extra day at the end of the graph. So, on the Charctic, NSIDC compares day 92 with day 92, but it does not adjust the graph to compare April 1st., 2006 (not leap year) with April 1st., 2016 (leap year).

Edit: Being April 1st April fools, It is ok that 2006 and 2016 look even, but their are not.  ;D

1802
Arctic sea ice / Re: 2016 sea ice area and extent data
« on: April 03, 2016, 01:33:51 AM »
One courious thing about NSIDC Charctic graph is that it is comparing April 2, 2006 with April 1, 2016. I would say that this happens because 2016 is a leap year.

The spring equinox fell on March 20th in both 2006 and 2016.  2016's vernal equinox fell about 14 hours earlier than 2006's - so leap year should have little effect

If you make a table by the day of the year, April 2, 2006 and April 1, 2016 will be day 92 of the year. 2006 will have 365 days and 2016 will have 366 days.
I haven´t check it, but it is posible that graphs like Charctic will only use the first 365 days in any year, so it will disregard Dic 31 on all leap years. I will check it later.

1803
Arctic sea ice / Re: 2016 sea ice area and extent data
« on: April 02, 2016, 10:58:10 PM »
One courious thing about NSIDC Charctic graph is that it is comparing April 2, 2006 with April 1, 2016. I would say that this happens because 2016 is a leap year. So today it looks that 2006 and 2016 are even. With this tendency, I believe that for NSIDC, tomorrow 2016 will be first on record.

Year          Apr 1     Apr 2      Apr 3
2006      14,232  14,241   14,235
2016      14,241


1804
Arctic sea ice / Re: The 2016 melting season
« on: March 31, 2016, 01:23:08 PM »
The bald fact is that after detrending, there is no correlation between the winter maximum and the summer minimum.  Everything beyond that is numerology.

I see a correlation between the winter minimum and the summer minimum. The low SIE years in winter had been 2005, 2006, 2007, 2011, 2015 and 2016.
The ASI melt crisis starts clearly in 2005. You can argue that other years -like 2002- were bad, but the tendency to lose ice on an accelerated speed, I believe it started at 2005.
2006 was a bad year and it had the possibility of break 2005 record on september. At the end it didn't happen, but it was bad enough to be noticed by NSIDC:

Quote
The relatively cool and stormy conditions that characterized August (see reports below) may have averted a repeat of the extreme ice losses of 2005.
http://nsidc.org/arcticseaicenews/2006/10/
   

Besides 2012, the worst years have been 2007, 2011 and 2015, all with low winter max.
So the only year that had a huge winter max and a very low summer minimum was 2012. All the other years that had a low winter record, had a significant summer minimum. Edit: So, looking at the years with september minimum, only 2012 had a huge winter max and a very low summer minimum. But all the years that had a low winter max, had a significant summer minimum.

Of course, we will have to wait to see what will happen in 2016, but from my point of view, the start of 2016 is really a bad sign, not to be underestimated.

1805
Arctic sea ice / Re: 2016 sea ice area and extent data
« on: March 29, 2016, 04:55:58 PM »
According to NSIDC, the latest on record is April 2,2010:

"The date of the maximum has varied considerably over the years, occurring as early as February 24 in 1996 and as late as April 2 in 2010."

http://nsidc.org/arcticseaicenews/2015/03/

Yes, but that's for NSIDC SIE. We were talking about CT SIA.

It's interesting to note that, despite occurring a full 40 days after last year's maximum, 2016 nevertheless has roughly 200,000 square kilometers less area today than on the same day last year.

That's why I 'wanted' it to be latest. Lowest and latest is a cool combination, as in freaky.

Thanks for the image. Very nice.

Thanks for the clarification. It is true, this year had a very interesting ASI freezing season.

1806
Arctic sea ice / Re: 2016 sea ice area and extent data
« on: March 29, 2016, 04:45:05 PM »
A big century drop almost certainly ends the march to the top, and starts the race to the bottom.

Not latest on record...  :'(  ;)

True...but only by a day. ...


According to NSIDC, the latest on record is April 2,2010:

"The date of the maximum has varied considerably over the years, occurring as early as February 24 in 1996 and as late as April 2 in 2010."

http://nsidc.org/arcticseaicenews/2015/03/

1807
Arctic sea ice / Re: 2016 sea ice area and extent data
« on: February 24, 2016, 08:47:55 PM »
Difficult to beleive that it is really happening...

1808
Arctic sea ice / Re: 2016 sea ice area and extent data
« on: February 16, 2016, 10:48:52 PM »
I am still waiting to see when the graph will go up, but as the days pass, I believe that we will have an end of freeze that will be the new lowest maximum record.  :o

1810
Arctic sea ice / Re: The 2015/2016 freezing season
« on: January 27, 2016, 10:31:44 PM »
The data from the weather buoys near the Pole has made it onto the web:

http://GreatWhiteCon.info/2016/01/more-heat-heading-for-north-pole/#comment-213287

The one on the Svalbard side reports that air temperatures managed to pop over "unfreezing point" briefly. Surface temperatures on the other hand, did not.

Great Charts Jim Hunt!

1811
Arctic sea ice / Re: 2016 sea ice area and extent data
« on: January 09, 2016, 04:42:18 PM »
After a "warm Arctic" at the end of 2015 and beginning of 2016, we start 2016 being the first on record. This could be for a short time frame, but from my point of view, having El Niño on 2016, we could be keeping from time to time this first lead, until the beginning of the melting season.

1812
Science / Re: Early Anthropocene
« on: January 09, 2016, 05:49:28 AM »
From my point of view, the Anthropocene should start when humanity generate a great event on the planet. Even that atomic bombs, per example, where an important event, they did not have a great effect on Earth. We can talk about the ozone hole, that is a great influence of humanity on our planet, but I believe that the greatest effect that humanity is going to make on our planet, that could change our lifestyle on very different ways, is the melt of the Arctic Sea Ice. This event can (and I believe it will) be the starting point to the melt of Greenland, to change the coastlines of the continents, it will accelerate global warming in different ways, etc.
So, from my point of view, 2007 should be considered the starting point to the Anthropocene.
I recommended you to see the following presentation of Mark Serreze on the 2007 AGU Fall Meeting and considered how he finds 2007 as a possible “point of no return” or “tipping point”, at the same time that he forecast 2030 as a year with a possible Arctic ice-free on summer. He also affirms that the Arctic sea ice will disappear abruptly, ¿so why a linear trend on all the NSIDC monthly graphs? After having 2007, 2011 and 2015 with almost the same level of ASI, and after 2012 with remarkably lower ice, shouldn´t we considerer 2007 as the year that mark the point of no return?

http://www.agu.org/webcast/fm07/Serreze/index.html

1813
Arctic sea ice / Re: 2016 sea ice area and extent data
« on: January 08, 2016, 05:13:56 PM »

My attempt at humor at Cryosphere's data glitches have evolved into something more serious and probably off topic but will add one response.


I was on focus with the topic, at the same time that I was making a statement with my signature, that appears on every post: past, present and future. Of course, I had also fun with Cryosphere's data glitches, at the same time that I enphasized my signature statement.  ;) ;D

I will remove CT from my signature, because they are not forcasting with 2D data and I will move my ASI social movement to another topic or I will create a new one.

Have a good day!

1814
Arctic sea ice / Re: 2016 sea ice area and extent data
« on: January 07, 2016, 07:42:04 PM »
I´m done with my new 2016 Forum signature, so I post an image of it, just to keep it that way. Sorry for all that changes in the last couple of days.

Here is what I think: Extent and area are great to follow the Arctic sea ice on a daily basis, but it is a huge mistake if we use them to forecast Arctic sea ice. It is the difference on talking about Arctic Ice-free on 2025 or 2100. We should push to remove this practice in institutions like the IPCC and the NSIDC, because then they underestimate the real speed of ASI change.

Have a good day and looking forward to participate on this forum on 2016!

1815
Arctic sea ice / Re: 2016 sea ice area and extent data
« on: January 07, 2016, 04:41:41 PM »
The recent above freezing temperature in the Arctic obviously had a disastrous effect...

We are in deep trouble ;-)

I'm feeling powerful! I'm sure that they read my new Forum signature and they made the correction!

Let's wait a couple of days and IPCC will do the same  ;) :D

1816
Arctic sea ice / Re: 2016 sea ice area and extent data
« on: January 06, 2016, 03:30:02 AM »
Becoming worst (or better, depending of the person that is writing). Too early for conclusions, but impressive. 1st. lowest on record.

1817
Consequences / Re: Weird Weather and anecdotal stories about climate change
« on: September 05, 2015, 05:34:33 AM »
This is climate change: Alaskan villagers struggle as island is chewed up by the sea:

http://www.latimes.com/nation/la-na-arctic-obama-20150830-story.html


1818
Arctic sea ice / Re: IJIS
« on: August 29, 2015, 12:00:59 AM »
This is amazing. I wonder when CT SIA is going to follow, because the combination of CT SIA stalling and IJIS/JAXA SIE dropping like a rock covered with armed concrete, is causing CAPIE to do crazy

From my point of view, this is distortion that could be related to satellite resolution and other ways to measure ice on NSIDC. With Wipneus comments, I understand that CT SIA is based on NSIDC figures. NSIDC SIE is 5.1 million km2 today (August 27) while IJIS/JAXA SIE is around 4.6 million km2. So, could we have the same distortion in NSIDC SIA, like we have it in SIE?

A small correction, Juan C, SIE of NSIDC stands at about 4.847 Millions of kilometers sq. (Aug 27)

I did not revised the daily figure, just the NSIDC Charctic graph that surely is based on the 5-day average, so you are right, maybe the difference is not that much.
Even so, there is around 250,000 km2 difference in NSIDC and IJIS/JAXA, looking at the 4.847 number. I want to ask if some knows why there is that difference. I think that it is related to satellite resolution, but is there another reason?

1819
Arctic sea ice / Re: IJIS
« on: August 28, 2015, 10:23:36 PM »
This is amazing. I wonder when CT SIA is going to follow, because the combination of CT SIA stalling and IJIS/JAXA SIE dropping like a rock covered with armed concrete, is causing CAPIE to do crazy stuff:



From my point of view, this is distortion that could be related to satellite resolution and other ways to measure ice on NSIDC. With Wipneus comments, I understand that CT SIA is based on NSIDC figures. NSIDC SIE is 5.1 million km2 today (August 27) while IJIS/JAXA SIE is around 4.6 million km2. So, could we have the same distortion in NSIDC SIA, like we have it in SIE?

1820
Arctic background / Re: Peter Wadhams in Murder Mystery?
« on: August 06, 2015, 03:39:48 PM »
1. how exactly there is a "hope" of "solving" (=preventing) big blue Arctic happening quite soon "anyways" - let's be generous and say within next 3 decades, - and then persisting (for increasingly large portion of summer/autumn times) in the Arctic? I mean, no matter whether things you said above are true or not, - isn't it that the hope is dead already, anyways? For me, it quite is; please enlighten me, if you may!

2. do we not have much over 550 ppm CO2e in the athmosphere right now, with no signs of stopping further growth?

3. is there any doubt that 500+ ppm CO2e in the athmosphere causes Blue Arctic, given sufficient time for the new equilibrium to set in?

Forecasting is like trying to know what is ahead of us, when we are driving looking at the rear view mirror. It is a good exercise and humanity should do it the best it can. But the true is that we can not known what will happen in the future.
So let's do our best and hope that the future will resolve this, even that we do not have hope now, looking at the rear view mirror.

1821
The forum / Re: Thanks for setting up the forum
« on: July 28, 2015, 02:38:54 PM »
for the first time, on July 2015 seems that it will reach the 1 million page views in one month!

You may want to check out July 2014.

congratulations for the great Forum success anyway

Woww! You are right. Seems that this year we will have a new record on July, but the 1 million mark was established last year.

1822
The forum / Re: Thanks for setting up the forum
« on: July 26, 2015, 06:04:35 PM »
It could be overrated, but anyway, it is the best measure we have of the activity of the Forum and for the first time, on July 2015 seems that it will reach the 1 million page views in one month! So congratulations for the great Forum success and thank you all for the effort that you have been making!

1823
Arctic sea ice / Re: The 2015 melting season
« on: July 22, 2015, 05:08:09 AM »
I'm impressed with the way it has deteriorated the Arctic sea ice on the Pacific Ocean side in just one week.

1824
Arctic sea ice / Re: Cyclones and ice-free Arctic
« on: June 26, 2015, 02:23:50 PM »
The issue is getting the energy to the ice in a way such that the ice melts. "cyclone merely speeds up the melt" downplays the impacts. I agree that the ice may have melted anyway but the speed up means that there is more time for other processes to occur (insolation, mixing of the cool 'just melted' water with warmer incoming water,increased contact area of ice to water etc.).  The above would be much clearer if upper ocean and ice were treated independently. In the (simple!) model in my head I treat them as separate systems. The problem then becomes getting the energy in the upper ocean to the ice. Cyclones are very effective at doing this.

I agree 100%. That's why I asked on this poll for a cyclone in June, July or August.
I believe that a cyclone of the same intensity than the GAC 2012, but in July, will collaborate to establish an ice-free Arctic in September, measure in CT area on a daily basis.

1825

On June 3th, the difference between 2010 and 2015 is 200,000 km2. So lets forecast 10.67 million km2 +/- 100,000 km2, as the 2015 NSIDC June Average.

I find hard to believe that I forecasted that NSIDC 2015 June average will be less than NSIDC 2010 June average!
In less than two weeks we will see if it is true.

1826
Arctic sea ice / Re: Cyclones and ice-free Arctic
« on: June 26, 2015, 05:11:02 AM »
Thank you for your comments!  ;) Some of them are very interesting.
Just one day left to make your vote!
Have a good day!

1827
Arctic sea ice / Re: Cyclones and ice-free Arctic
« on: June 24, 2015, 04:10:00 AM »
"Did GAC 2012 really just cause 0.15M km^2 of loss? It's not a rigorously scientific position, evidence from a reliable model counters it, but when I look at what happened in terms of anomalies of sea ice extent, it is too much for me to swallow that the Great Arctic Cyclone of 2012 had little impact."
Chris Reynolds: http://dosbat.blogspot.co.uk/2015/06/what-role-did-gac-of-2012-play-in-2012.html

For me it is also very dificult to accept that the 2012 Great Arctic Cyclone only caused 0.15M km2 of SIE lost. It was the first Arctic cyclone that I followed and the way Neven announced it1 and the way it divided the Arctic Sea Ice in two, was really impresive.

I don´t hope to see another cyclone like that one (seems apocalyptical to me) but I believe that it will happen again  in the following 10 years.

1 http://neven1.typepad.com/blog/2012/08/cyclone-warning.html

1828
Greenland and Arctic Circle / Re: Greenland 2015 Melt Season
« on: June 23, 2015, 09:34:06 PM »
We are now having our first "big" melting event for the year:

The melting increase in only two days:

1829
Arctic sea ice / Re: Arctic Image of the Day
« on: June 20, 2015, 11:07:18 PM »

1830
Arctic sea ice / Re: Cyclones and ice-free Arctic
« on: June 20, 2015, 06:15:51 AM »
The small cyclone is better organized today than yesterday. It has moved away from the Asian coast, but it is still bringing heat to the Arctic.
Most of the Arctic has the air at surface with temperature more than 0ºC.
A crack is appearing on the East Siberian Sea.


1831
Arctic sea ice / Re: Cyclones and ice-free Arctic
« on: June 19, 2015, 08:42:05 AM »
It is interesting the form in which this small cyclone is bringing heat from Asia to the East Siberian Sea (ESS).
I wonder how much time the ESS and the Beaufort Sea will stay with healthy sea ice.

1832
Arctic sea ice / Re: The 2015 melting season
« on: June 18, 2015, 04:22:44 AM »
Nullschool uses GFS, so it ostensibly has similar reliability.

There's some helpful info on the "about" page: http://earth.nullschool.net/about.html

Thank you sedziobs  ;)

1833
Arctic sea ice / Re: The 2015 melting season
« on: June 18, 2015, 03:04:35 AM »
Nullschool says that temperature at the Arctic is from 0.1ºC to 4.9ºC
How much reliable is nullschool?
Where I can learn to use it?

1834
Well, 9 hours to make your vote (or change it if you want to...).

1835
Well, 9 hours to make your vote (or change it if you want to...).

1836
Arctic sea ice / Re: Cyclones and ice-free Arctic
« on: June 12, 2015, 05:40:53 AM »
I am just guessing, but I think that it is moving ice from Kara Sea and the Arctic Basin to Barents Sea. This sea ice movement will make open water on Kara Sea and the sea ice will melt on Barents Sea on a couple of weeks (maybe 3 weeks).

1837
Arctic sea ice / Re: Cyclones and ice-free Arctic
« on: June 12, 2015, 05:25:54 AM »
Now we have an Arctic Storm (I can´t say that it is a 67 km/hr "tropical" storm ;) ) at Barents Sea. How do you believe it is going to affect the melt season?

Thanks for your answers.

http://earth.nullschool.net/#current/wind/surface/level/orthographic=-59.41,92.76,1295


1838
Arctic sea ice / Re: Cyclones and ice-free Arctic
« on: June 08, 2015, 06:25:34 AM »
Thank you Vergent, Gray-Wolf and Nick_Naylor for your comments.

Just to follow the answer of Vergent to Nick_Naylor question:



The arctic albedo is at least 20% below 2012. The area is the same. That corresponds to 100 watts in full sunlight. Discounting it to 50 watts for cloud cover, that will still melt 0.8 meters of ice over 60 days. Over 9 M km^2, that corresponds to 8 kkm^3. Eyeballing PIOMAS, that would put us in negative numbers. The poll didn't have negative numbers, so I picked the bottom bucket.

Verg

1839
Arctic sea ice / Cyclones and ice-free Arctic
« on: June 07, 2015, 12:18:16 AM »
We define ice-free Arctic as a day in which there is less than 1 million km2 of Arctic sea ice area, measure by Cryosphere Today

1840
At this moment it is difficult for me to understand why the NSIDC 2012 June Average is below the 2011 June Average. But anyway, I already made my forecast...  ;D

1841
Thank you, Oren, Paddy and ChrisReynolds for your comments.

NSIDC has already published the May figures and "May 2015 averaged 12.65 million square kilometers (4.88 million square miles), the third lowest May ice extent in the satellite record."

But what it is interesting is if we can forecast the breaking record that we should have on June 2015, that is competing with 2010, 2011 and 2012, being 2010 the smallest figure with 10.87 million square kilometers.

The 2015 NSIDC June Average will depend on ice concentration (Charctic shows extent but no concentration) and ice movement. But lets ignore those two components.

On June 3th, the difference between 2010 and 2015 is 200,000 km2. So lets forecast 10.67 million km2 +/- 100,000 km2, as the 2015 NSIDC June Average.


1842
Juan,
I wondered what you meant (on May 29) when you wrote "NSIDC June average is defined the first 7 days of June".  Now I know.  Thanks for the explanation.

You are welcome Tor Bejnar.
Regarding the 2015 May average, I do not expect that we will have a new record on 2015, but it could be. The true is that the ice that is moving on the second part of the month also plays some role.
If we see only the NSIDC Charctic Graph and we concentrate on the begining of May, then 2004 should be above 2006 May Average. But 2006 May average was above 2004 May Average.
My bet is that on May 2015 we will not break the record, but we will do it on June 2015.
Let's wait and see.

1843
NSIDC:

"2.2 Mean Concentration Fields and Median Ice Edge Position
On monthly extent images, ice ends and water begins where the concentration estimates of grid cells in the gridded average, or mean, concentration field for that month drop below 15 percent."
http://nsidc.org/data/docs/noaa/g02135_seaice_index/

NSIDC uses a method to calculate the Monthly Average, that it is different to what we usually think as an average. For NSIDC, if a grid cell has ice in 15% of the days or more, then the grid cell has ice for all the month. In May we have 31 days and 15% of 31 days is 4.65 days.
Rounding to 5 days, if a grid has 5 days with 100% ice, it means that the grid cell will have 100% ice, in order to calculate de NSIDC SIE for the month. If another grid cell has 50% of ice for 10 days in the month, that grid cell also enters with 100% ice to calculate the average.
Given this rules to calculate NSIDC Monthly Average, in months that there is SIE melting, the first 5 or 10 days of the month are the ones that "turn on" most of the grid cells that will defined the NSIDC Monthly Average.
So it is not important what happened on the last 15 days of May 2015, the May NSIDC Monthly Average will reflect what happen on the first days of May.
On the other hand, on the first days of June we are having daily records that are below to any other year. On a usual month, that will be enough to make us have a NSIDC June 2015 record. The only thing that could change that is if something very unusual happens, like a cyclon moving the ice to a region that was free of ice at the beginning of the month. If that happens and a grid cell has ice on 15% of the days, then that grid cell will also contribute to establish the NSIDC monthly average.
For me, it was interesting that I was able to predict a June record on NSIDC monthly Average, at the ending of May:

It is very interesting the form in which the NSIDC SIE has fallen apart on the last two weeks. It hasn't been seen in any other year. Knowing that the NSIDC June average is defined the first 7 days of June, we are going to have a huge record on NSIDC June SIE average, when it will be announced on July.

1844
Arctic sea ice / Re: The 2015 melting season
« on: May 31, 2015, 04:28:24 AM »
Do we have a cyclon at Barents Sea?
Will it push some Arctic sea ice to the hotter waters of the Atlantic?

1845
Arctic sea ice / Re: 2015 sea ice area and extent data
« on: May 30, 2015, 03:37:43 AM »
It is very interesting the form in which the NSIDC SIE has fallen apart on the last two weeks. It hasn't been seen in any other year. Knowing that the NSIDC June average is defined the first 7 days of June, we are going to have a huge record on NSIDC June SIE average, when it will be announced on July.


1846
Arctic sea ice / Re: Arctic Image of the Day
« on: June 12, 2014, 05:41:30 AM »
Thanks for the link, trebuh.
In a way, you show me I am right in my comment.
It is true that we had an important Laptev bite at 1990, but the sea ice at 1990 was strong, so it didn´t develop the way it is going to develop at 2014. On the other hand, if we check the other years, there was not an important Laptev bite until 2007 and 2012 (2009 has no data).
In a way, I am dissapointed that I asked for an action in this forum and some forum users answered that we should not have "we ought to..." proposals on this forum.
Surely I was not active enough. I should push harder.
Anyway, the true is that at 2013, the IPCC was critized for exagerating AWG, when my point of view is that it is the other way around.

What do you think? Do you agree that the IPCC models, as they are right now, are worthless? Would you like to make the effort to include a PIOMAS volume forecast on the USA Third Climate Assessment Report?

1847
Arctic sea ice / Re: Arctic Image of the Day
« on: June 11, 2014, 07:12:24 AM »
What do you see here?
Well, what I see is a lake (the Laptev bite), with kind of the shape and possibly the size of the United Kingdom Island, in a place that we would not dreamed ten years ago. But the Arctic sea ice is OK. At 2014 we are far from reaching the 2012 record, so we have to wait until all the Arctic sea ice is gone, in order to believe that AGW is happening. Anyway, thanks to Global Warming, we have new maritime routes at the Arctic.
Yes, I am being sarcastic. Isn't this reality bad enough? We should wait until the permafrost will melt, releasing methane and CO2? In my opinion, this waiting time until we reach another record is a waste of time. There should be a special place on this forum with the name "We ought to..."

1848
Taking into account the great fall that CT SIA had these past 7 days, I change to the next lower level:
Between 2.5 and 2.75 million km2.

1849
My prediction is that CT Area at minimum will be:

CTA - 5.311 Mkm^2 at minimum.
With bounds of +0.24Mkm^2, -0.27Mkm^2.

Where CTA is CT Area on June 20th.

But as I don't know what the area will be on June 20th, I can't make the prediction at this stage.  :P

Isn't that too high, CrisReynolds?

1850
Between 2.75 and 3.0 million km2

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