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1
Policy and solutions / New ideas for carbon capture
« on: July 14, 2017, 11:31:25 AM »
This thread was opened by Jontenoy in the wrong category. I wanted to move it here, but accidentally removed it. Fortunately it was still in my cache. Here's Jontenoy's text:

---

Most discussions seem to be about reducing emissions. This is all fine except it is not going to happen fast enough. I think a possible solution would be to develop a vegetable with the following attributes :
* Has deep roots
* Produces food (grains, leaves, stalks etc)
* Keeps growing downwards
* Spreads rapidly

This would produce a vast tangle of treadlike roots which would capture and store carbon. If it died, a new plant could continue and grow around the old roots. Clover fixes Nitrogen. This would fix Carbon in the soil as biomass.  Some grape vines and Olive trees have roots greater than 40 metres deep.
The same idea could be considered for the ocean whereby algae would form, reproduce and die on a continuous basis.

2
Arctic sea ice / MOVED: Fish and sea ice
« on: July 10, 2017, 02:54:02 PM »

3
Arctic sea ice / NSIDC 2017 Arctic SIE September average: July poll
« on: July 01, 2017, 12:46:08 PM »
ATTENTION: There are two polls on the ASIF. This one is for NSIDC sea ice extent monthly minimum or September average (which is also used for the SIPN sea ice outlook), the other is for JAXA sea ice extent daily minimum (provided by ADS, previously by IJIS). Make sure you are aware of the difference before voting. You can discuss various extent/area data sets in this dedicated thread.

-----

This NSIDC extent poll will run for 11 days (until July 12th). Until then you can change your vote. Here are the results for the June poll. There will be a new poll next month.

Here's how things are currently looking based on data up to June 30th:



These are the September averages for the last 12 years (in millions km2, found here):

    2005: 5.59
    2006: 5.95
    2007: 4.32
    2008: 4.74
    2009: 5.39
    2010: 4.93
    2011: 4.63
    2012: 3.63
    2013: 5.35
    2014: 5.29
    2015: 4.68
    2016: 4.72

You can use the comment thread below to motivate your choice, but discuss various SIE/SIA data sets in this dedicated thread.

5
Arctic sea ice / NSIDC 2017 Arctic SIE September average: June poll
« on: June 01, 2017, 10:39:12 PM »
ATTENTION: There are two polls on the ASIF. This one is for NSIDC sea ice extent monthly/September average minimum (which is also used for the SIPN sea ice outlook), the other is for JAXA sea ice extent daily minimum (provided by ADS, previously by IJIS). Make sure you are aware of the difference before voting. You can discuss various extent/area data sets in this dedicated thread.

-----

This NSIDC extent poll will run for 11 days (until June 12th). Until then you can change your vote. There will be a new poll next month.

Here's how things are currently looking based on data up to May 31st:



These are the September minimums for the last 12 years (in millions km2, found here):

    2005: 5.59
    2006: 5.95
    2007: 4.32
    2008: 4.74
    2009: 5.39
    2010: 4.93
    2011: 4.63
    2012: 3.63
    2013: 5.35
    2014: 5.29
    2015: 4.68
    2016: 4.72

You can use the comment thread below to motivate your choice, but discuss various SIE/SIA data sets in this dedicated thread.

7
Greenland and Arctic Circle / Greenland 2017 melt season
« on: May 22, 2017, 01:50:16 PM »





9
Science / MOVED: Real Stupid Blog-Posts
« on: April 27, 2017, 08:41:03 PM »

10
The rest / Russiagate
« on: April 22, 2017, 10:03:30 PM »
This thread is for discussing every aspect of the alleged (and allegedly successful) attempts by the Russian government to influence the last American presidential elections.

Have at it.

11
Developers Corner / MOVED: Closed forum or mailing list
« on: April 17, 2017, 10:33:45 AM »

12
The rest / The problem of Corporate Democrats and how to kick them out
« on: March 29, 2017, 10:36:31 PM »
Okay, I've been having these ongoing discussions in the Trump thread, even though I perhaps shouldn't (I'm not American and I don't have the time or the knowledge to give such a discussion the attention it deserves), but I'm just constantly frustrated to see how people fall into this groupthink that is mainly served up by mainstream media and focuses on any spectacle that turns the attention away from the real problem: The iron hold of corporations on American politics.

Of course, we all know how effed up the Republican Party and how they lie and cheat people, while serving the interests of the military-industrial complex, Big Fossil, Big Agro, and so on.  The problem is that the Democratic Party isn't any better. In fact, I would say it's even worse, because these Corporate Democrats act as if they represent the opposite of the Republican Party and are the party of the (working) people, whereas in fact, they too mostly serve the interests of Wall Street, Big Pharma and the military-industrial complex and so on.

And that's how you get Trump. First, he ate the Republican presidential candidates' lunch and won the primaries (with the help, as it turned out, from Clinton and her mainstream media network) and then he clinched victory away from the vastly unpopular Clinton who paid millions and millions for ads, outspending Trump 2:1, mostly smearing Trump instead of presenting ideas and inspiring people to come and vote for her. It was an absolute strategic disaster, so bad that I sometimes think they did it on purpose.

The problem is now that everyone is so anti-Trump that they're unwilling to look at how all this came about, and unwilling to try and change that, while taking on Trump at the same time. It's all Trump, Trump, Trump. That's the current message from the Democratic Party: We're not Trump. No ideas, no vision, no values, just 'We're not Trump'.

By constantly focussing on Trump's character and things like Russian influences (McCarthyism all over again, never mind the beam in thine eye) things are probably set up in such a way that Trump stays firmly in power and the Republicans keep their majority. And even if they don't, it's the Corporate Democrats that get some power back again to serve special interests again. So, corporations and rich people win either way.

What I and others have tried to make clear in the Trump thread is that some of that energy channeled towards Trump, needs to be use to either start a third party (which is very difficult) or sweep the Democratic Party clean, and get some true progressives in that can win back the trust of the people.

And so I've opened this separate thread to try and discuss with others to see if they agree, and if not, why not and what should happen instead. Why choose to die from the lesser poison, if the end result is the same?

15
The rest / MOVED: Baltic Images
« on: March 19, 2017, 01:01:34 PM »

16
Arctic Background / MOVED: Validation of GCM Models.
« on: March 18, 2017, 12:23:36 AM »

17
The rest / MOVED: Ocean Temps
« on: March 11, 2017, 09:22:05 AM »

18
The rest / MOVED: What is Off Topic and What is Not?
« on: March 11, 2017, 09:21:14 AM »
This is clearly about the Forum, and hence the automatic notification:

This topic has been moved to The forum.

http://forum.arctic-sea-ice.net/index.php?topic=1907.0

19
Arctic sea ice / MOVED: Barneo 2017
« on: March 09, 2017, 10:19:55 PM »

20
The forum / Moderation
« on: March 09, 2017, 09:34:03 PM »
The Forum keeps growing, which is great news, but there are some downsides as well, the most conspicuous of course being off-topic comments and rants in the wrong threads, especially the ones with most readers, such as the freezing/melting threads, and the IJIS and PIOMAS threads. Lately this has been really getting out of hand.

I've decided to do two things:

1. Delete those off-topic comments for a while, to see if that helps. It entails extra work, but so do the moderator reports, warning people and PM-ing back and forth.
2. Forum member and long time ASIB commenter Jim Pettit has offered to help out, and so I've decided to assign him the role of General Moderator, which allows him to intervene with all kinds of things, like approving comments from new members, moving threads, modifying polls when necessary, etc.

That should get us through the coming melting season.  ;)

21
Arctic sea ice / MOVED: 2017 open thread
« on: March 04, 2017, 08:57:43 PM »

22
Arctic sea ice / MOVED: Ice-free Arctic
« on: February 23, 2017, 02:14:32 PM »

24
Arctic sea ice / Arctic temperature layers and inversions
« on: February 18, 2017, 10:43:25 PM »
Over on the 2016/2017 freezing season thread, commenter Aslan is providing lots of information that shouldn't get lost in the mire of comments. And so I open this thread to make it easier to find.

Below is Aslan's post:

---------

Using the reanalysis, we can calculate also the mean of the downward radiation flux. Of course, it is the reanalysis, with a coarse resolution and its own limitations (especially discontinuities due to inclusion of varying kinds of data), but I think it is quite good nonetheless, if we look at the values after 1981 (start of the satellite era). So, the downward radiation flux, or the infrared emitted by the atmosphere toward Earth surface (one funny thing when you have some knowledge in physics, you know you are a being of light and that you are shining :D ). Data are for the whole above 69°N (radiation data are along a Gauss grid, I take values up to 69.5217°N, cell index 11), averaged according to surface (hoping I make no mistakes), for each day from 1st January, 1981 :



It is looking quite like the graph of the temperature according to the DNMI, which is not unexpected by the way. We are tempted to say, a warmer atmosphere radiates more energy, so what is the point?

Actually there is more in this. The mean level of radiation for Earth is around 5 - 6 km, so around 500 hPa, take or given a couple of hPa. Relationship between temperature and radiation is not linear, so we can calculate the flux of a black-body with our old friend, the equation of a black-body :

Flux = 5.67e-8 * T^4

The grid for the temperatures are not the same as the one for the radiation data, but I didn't care about this. The precision of the reanalysis is probably far worse than the small difference induced by averaging over a slightly different area. So I used the region above 67.5°N for the temperatures, calculate the radiation flux from the temperature and compare with DWLR, and averaged for the three months from November to January (February is still ongoing un 2017). The year of reference is that of January (ie., NDJ 2017 is the average of ND 2016 and J 2017) :



Values are roughly the same, so yeah 500 hPa is a good level. But correlation is not looking good actually... I look to other levels, but the correlation is not significantly better. As a side-note, the temperatures at 500 hPa :



So, what if we try with the precipitable water?



It looks way better...

So I detrend the series, to compare the cross-correlation. Anomalies of the downward radiation flux, explained by the anomalies of the black-body emmision :



Anomalies of the downward radiation flux, explained by the anomalies of the precipitable water :



Anomalies of the anomalies of the precipitable water, explained by the temperature at 500 hPa :



I will not try an argument about chickens and eggs. It is of course difficult to disentangled all the mechanisms ongoing. But at least the increasing of water vapor, linked to warming of the temperatures but also to the decrease of Arctic sea ice, is increasing downward radiations.

The major point is that a warming of 20°C or 30°C is not impossible at surface is thus not impossible. With global warming, the "thin" -a 2 km thick and 20°C inversion is massive for an inversion in the absolute, but compared to the whole atmosphere this it is not so thick nor so cold- the "thin" layer of permanent inversion is set to be destroyed, with only marginal warming above. Usually there is around 5 to 10°C between surface and 850 hPa. Even a 7-8°C lapse rate with a 850 hPa layer around 250K would imply a mean surface temperature a bit below 260K, around -15°C, barely enough cold for sea ice. This graph shows the warming of the Arctic layers :



The surface 1000 hPa is warming fast and is now warmer than the 850 hPa for the first time since 1981 (and probably since many millenniums...). And the strength of the inversion (or of the now non-inversion) taken as the difference between the 850 hPa and 1000 hPa temperatures :





I will post the spreadsheet with the data a bit latter ;)

P.S. : THe spreadsheet www.climatvisu.fr/Neven_ASIF/dlwr_out_2.ods

26
Arctic sea ice / MOVED: Milankovich Cycle doubts
« on: January 31, 2017, 09:17:01 PM »

29
Arctic sea ice / MOVED: NVM
« on: January 16, 2017, 07:42:15 PM »

30
Arctic sea ice / Updating the ASIG
« on: January 04, 2017, 10:40:41 PM »
It's time for another bi-annual update of the Arctic Sea Ice Graphs website. Unfortunately and sadly, I will have to remove Andrew Slater's excellent graphs. As Cryosphere Today's graphs haven't been updated since the problems with DSMP satellite F-17 (and no one has responded to my queries), I will have to remove them too. Furthermore, Climate Reanalyzer have again changed a couple of things on their side, so I need to update the links on the Forecasts page. I'll try and update the Long-term Graphs page as well. I'll probably do the Concentration maps page next month or so, as that is a lot of manual work.

Does anyone know of replacement graphs, or perhaps new graphs altogether? I've seen some precipitable water and vapour stuff pass by on several threads, but never followed them to see if they're useful.

Mind you, I prefer links to graphs that are automatically updated (so they're updated on the ASIG as well), not static images that change extension, as I don't know how to write scripts to automatically update those on the ASIG.

Thanks in advance for any suggestions/ideas.

31
Arctic sea ice / 2017 sea ice area and extent data
« on: January 03, 2017, 01:14:06 PM »
Someone told me a new year has started, so here's a new thread to replace the 2016 version.

Have at it, spread the data.

33
The forum / 1000 members
« on: August 06, 2016, 11:08:46 AM »
The forum is about to have 1000 members. Maybe there are a few inactive spambots in there, but I generally block/ban all of them.

34
Arctic sea ice / NSIDC 2016 Arctic SIE September minimum: August poll
« on: August 01, 2016, 01:04:49 PM »
ATTENTION: There are two polls on the ASIF. One is for NSIDC sea ice extent monthly/September average minimum (the one that is used for the SIPN sea ice outlook), the other is for JAXA sea ice extent daily minimum (provided by ADS, previously by IJIS). Make sure you are aware of the difference before voting. You can discuss various extent/area data sets in this dedicated thread.

-----

This NSIDC extent poll will run for 10 days (until August 11th). Until then you can change your vote. This is the last poll for this melting season.

Here's how things are currently looking based on data up to July 31st:



These are the September minimums for the last 11 years (in millions km2, found here):

    2005: 5.57
    2006: 5.92
    2007: 4.30
    2008: 4.73
    2009: 5.39
    2010: 4.93
    2011: 4.63
    2012: 3.63
    2013: 5.35
    2014: 5.28
    2015: 4.63

You can use the comment thread below to motivate your choice, but discuss various SIE/SIA data sets in this dedicated thread.

35
Arctic sea ice / NSIDC 2016 Arctic SIE September minimum: July poll
« on: July 02, 2016, 10:28:55 PM »
ATTENTION: There are two polls on the ASIF. One is for NSIDC sea ice extent monthly/September average minimum (the one that is used for the SIPN sea ice outlook), the other is for JAXA sea ice extent daily minimum (provided by ADS, previously by IJIS). Make sure you are aware of the difference before voting. You can discuss various extent/area data sets in this dedicated thread.

-----

This NSIDC extent poll will run for 10 days (until July 12th). Until then you can change your vote. There will be a new poll next month.

Here's how things are currently looking based on data up to June 30th:



These are the September minimums for the last 11 years (in millions km2, found here):

    2005: 5.57
    2006: 5.92
    2007: 4.30
    2008: 4.73
    2009: 5.39
    2010: 4.93
    2011: 4.63
    2012: 3.63
    2013: 5.35
    2014: 5.28
    2015: 4.63

You can use the comment thread below to motivate your choice, but discuss various SIE/SIA data sets in this dedicated thread.

36
The rest / MOVED: Cycling
« on: June 23, 2016, 09:54:57 PM »

37
Arctic sea ice / NSIDC 2016 Arctic SIE September minimum: June poll
« on: June 13, 2016, 11:44:17 PM »
ATTENTION: There are two polls on the ASIF. One is for NSIDC sea ice extent monthly/September average minimum (the one that is used for the SIPN sea ice outlook), the other is for JAXA sea ice extent daily minimum (provided by ADS, previously by IJIS). Make sure you are aware of the difference before voting. You can discuss various extent/area data sets in this dedicated thread.

-----

This NSIDC extent poll will run for 7 days (until June 20th). Until then you can change your vote. There will be a new poll next month.

Here's how things are currently looking based on data up to June 12th:



These are the September minimums for the last 11 years (in millions km2, found here):

    2005: 5.57
    2006: 5.92
    2007: 4.30
    2008: 4.73
    2009: 5.39
    2010: 4.93
    2011: 4.63
    2012: 3.63
    2013: 5.35
    2014: 5.28
    2015: 4.63

You can use the comment thread below to motivate your choice, but discuss various SIE/SIA data sets in this dedicated thread.

38
Arctic sea ice / MOVED: Forum Decorum
« on: May 26, 2016, 05:06:08 PM »

41
Arctic sea ice / 2016 sea ice area and extent data
« on: January 06, 2016, 12:01:15 AM »
This thread replaces the 2015 version.

Last comment:

Update for the week to January 2nd

The current 5 day mean is on 12,797,800km2 while the 1 day extent is at 12,811,000km2.

The daily anomaly (compared to 81-10) is at -921,490km2, an increase from -775,320km2 last week. The anomaly compared to the 07, 11 and 12 average is at -206,470km2, an increase from -70,13km2 last week. We're currently 2nd lowest on record, up from 4th lowest last week.



The average daily change over the last 7 days was +33.2k/day, compared to the long term average of +54.1k/day, and the 07, 11 and 12 average of +52.7k/day.
The average long term change over the next week is +53.8k/day, with the 07, 11, and 12 average being +51.8k/day.



The increase so far this January is the smallest on record. To achieve the smallest monthly gain, an increase of less than 28.1k/day is required, while the largest monthly gain requires an increase of at least 61.6k/day and an average gain requires an increase of 45.0k/day.



The increase this December was the 18th largest on record, while the average extent was the 5th smallest on record.






Have at it.

43
Glaciers / Himalayan glaciers
« on: November 26, 2015, 04:29:37 PM »
There wasn't a topic yet for this specific subject (I think), and this work that has just been published might be a good topic opener:

Revealing glacier flow and surge dynamics from animated satellite image sequences: examples from the Karakoram

F. Paul
Department of Geography, University of Zurich, Zurich, Switzerland

Abstract. Although animated images are very popular on the internet, they have so far found only limited use for glaciological applications. With long time series of satellite images becoming increasingly available and glaciers being well recognized for their rapid changes and variable flow dynamics, animated sequences of multiple satellite images reveal glacier dynamics in a time-lapse mode, making the otherwise slow changes of glacier movement visible and understandable to the wider public. For this study, animated image sequences were created for four regions in the central Karakoram mountain range over a 25-year time period (1990–2015) from freely available image quick-looks of orthorectified Landsat scenes. The animations play automatically in a web browser and reveal highly complex patterns of glacier flow and surge dynamics that are difficult to obtain by other methods. In contrast to other regions, surging glaciers in the Karakoram are often small (10 km2 or less), steep, debris-free, and advance for several years to decades at relatively low annual rates (about 100 m a−1). These characteristics overlap with those of non-surge-type glaciers, making a clear identification difficult. However, as in other regions, the surging glaciers in the central Karakoram also show sudden increases of flow velocity and mass waves travelling down glacier. The surges of individual glaciers are generally out of phase, indicating a limited climatic control on their dynamics. On the other hand, nearly all other glaciers in the region are either stable or slightly advancing, indicating balanced or even positive mass budgets over the past few decades.


The Cryosphere

And EGU press release here (where the animations can be viewed)

47
Policy and solutions / MOVED: The Great Victorian Weather Wars
« on: August 09, 2015, 09:04:56 PM »
Thanks OLN, this topic has been moved to Science.

http://forum.arctic-sea-ice.net/index.php?topic=1357.0

48
ATTENTION: There are two polls on the ASIF. One is for NSIDC sea ice extent monthly/September average minimum, the other is for Cryosphere Today sea ice area daily minimum. Make sure you are aware of the difference before voting. You can discuss various extent/area data sets in this dedicated thread.

-----

This CT SIA poll will run for 12 days (until August 13th). Until then you can change your vote. This is this year's last poll.

Here's how things are currently looking based on data up to July 31st:



These are the daily minimums for the last 7 years (in millions km2):

    2005: 4.092
    2006: 4.030
    2007: 2.919
    2008: 3.004
    2009: 3.425
    2010: 3.072
    2011: 2.905
    2012: 2.234
    2013: 3.554
    2014: 3.483

You can use the comment thread below to motivate your choice, but discuss various SIE/SIA data sets in this dedicated thread.

49
Arctic sea ice / NSIDC 2015 Arctic SIE September minimum: August poll
« on: August 01, 2015, 11:24:06 AM »
ATTENTION: There are two polls on the ASIF. One is for NSIDC sea ice extent monthly/September average minimum, the other is for Cryosphere Today sea ice area daily minimum. Make sure you are aware of the difference before voting. You can discuss various extent/area data sets in this dedicated thread.

-----

This NSIDC extent poll will run for 12 days (until August 13th). Until then you can change your vote. This is this year's last poll.

Here's how things are currently looking based on data up to July 30th:



These are the September minimums for the last 8 years (in millions km2, found here):

    2005: 5.57
    2006: 5.92
    2007: 4.30
    2008: 4.73
    2009: 5.39
    2010: 4.93
    2011: 4.63
    2012: 3.63
    2013: 5.35
    2014: 5.28

You can use the comment thread below to motivate your choice, but discuss various SIE/SIA data sets in this dedicated thread.

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