Support the Arctic Sea Ice Forum and Blog

Author Topic: "Stupid" Questions :o  (Read 553829 times)

sidd

  • Young ice
  • Posts: 4980
    • View Profile
  • Liked: 383
  • Likes Given: 0
Re: "Stupid" Questions :o
« Reply #1850 on: May 20, 2019, 11:09:02 PM »
Re: Do melt ponds have any mechanical effect on sea ice

If they get deep enuf the pressure can form a crevasse all the way to the bottom (hydrofracture)

sidd
 

Tor Bejnar

  • Young ice
  • Posts: 3108
    • View Profile
  • Liked: 402
  • Likes Given: 198
Re: "Stupid" Questions :o
« Reply #1851 on: May 21, 2019, 05:17:18 AM »
Melt ponds, given they are made of water, are affected by wind, and little waves eat away at the edges.  We watched images from a camera-ed buoy a few years ago (e.g., see the pages of comments around this What the Buoys are telling post). 
Arctic ice is healthy for children and other living things.

b_lumenkraft

  • Guest
Re: "Stupid" Questions :o
« Reply #1852 on: May 21, 2019, 06:58:26 AM »
Something wrong with https://www.polarview.aq ??
No more new radar shots since 18th early morning for both, Antarctic and Arctic.
It happens for a couple of days every two months or so. I don't know why.

Thanks, man. It's back now. :)

binntho

  • Nilas ice
  • Posts: 1095
    • View Profile
  • Liked: 282
  • Likes Given: 76
Re: "Stupid" Questions :o
« Reply #1853 on: May 21, 2019, 09:11:46 AM »
Do melt ponds have any mechanical effect on sea ice or are they strictly important due to albedo change?

I seem to remember research that showed that the fresh water in the melt pond seeps into cracks in the ice and refreezes there, effectively creating it's own impermeable layer rather than just seeping out through the bottom of the ice (as would otherwise happen, since water is denser than ice, and the ice is often highly fractured).
because a thing is eloquently expressed it should not be taken to be as necessarily true
St. Augustine, Confessions V, 6

Jim Hunt

  • Young ice
  • Posts: 4289
    • View Profile
    • The Arctic sea ice Great White Con
  • Liked: 274
  • Likes Given: 27
Re: "Stupid" Questions :o
« Reply #1854 on: May 21, 2019, 02:21:07 PM »
I seem to remember research that showed that the fresh water in the melt pond seeps into cracks in the ice and refreezes there, effectively creating it's own impermeable layer rather than just seeping out through the bottom of the ice (as would otherwise happen, since water is denser than ice, and the ice is often highly fractured).

Quite so. See also the "North Pole Lake" of 2013:

http://psc.apl.washington.edu/northpole/NPEO2013_webcams.html



Quote
When the top surface of a melt pond reaches above the freeboard of the ice floe floating in sea water, melting from both above and below will often penetrate the bottom of the pond at the thinnest point, causing the pond above the ocean line to drain, often quite abruptly.
Reality is merely an illusion, albeit a very persistent one - Albert Einstein

Darvince

  • Frazil ice
  • Posts: 287
    • View Profile
    • NSIDC Daily
  • Liked: 19
  • Likes Given: 6
Re: "Stupid" Questions :o
« Reply #1855 on: May 24, 2019, 01:40:47 AM »
Here is my stupid question:
What is CO2e now?
I don't mean the definition, I mean the number. Searching I find an implication that it is still below 500 ppm but will reach it BAU within a decade of 2016:
https://forum.arctic-sea-ice.net/index.php/topic,1762.msg92315.html#msg92315
or by 2025:
https://forum.arctic-sea-ice.net/index.php/topic,1056.msg39615.html#msg39615
and an implication that it is about 720 ppm "near term":
https://forum.arctic-sea-ice.net/index.php/topic,143.msg196439.html#msg196439
Either I am misreading the messages, or they substantially disagree.
Can anyone give me current CO2e?
As an addendum: I have noticed that much of the discourse over this has been because of fighting over the correct timeframe to use for all the methane at once. Could it be possible, but moreso physically justifiable, to do a calculation that uses the CO2e of one year for atmospheric methane increase in 2018, 2 years for 2017, etc, and thereby get around this fight and arrive at a new number people can agree on?

VaughnAn

  • New ice
  • Posts: 64
    • View Profile
  • Liked: 33
  • Likes Given: 325
Re: "Stupid" Questions :o
« Reply #1856 on: May 24, 2019, 07:12:34 AM »
Darvince, see the "Toward Improved Discussions of Methane and Climate" Thread.  There is a discussion about your musings there.

https://forum.arctic-sea-ice.net/index.php/topic,480.msg198609.html#msg198609

petm

  • Grease ice
  • Posts: 675
    • View Profile
  • Liked: 335
  • Likes Given: 27
Re: "Stupid" Questions :o
« Reply #1857 on: May 26, 2019, 05:13:28 AM »
http://lmgtfy.com/?q=entitled

Sorry for the OT, couldn't resist. This is a stupid comment rather than a stupid question.

oren

  • Young ice
  • Posts: 4532
    • View Profile
  • Liked: 910
  • Likes Given: 1305
Re: "Stupid" Questions :o
« Reply #1858 on: May 26, 2019, 12:19:26 PM »
Welcome petm. Perhaps not the best strategy to start off with a cryptic message... but if you have real questions feel free to ask.

Shared Humanity

  • Young ice
  • Posts: 3979
    • View Profile
  • Liked: 429
  • Likes Given: 52
Re: "Stupid" Questions :o
« Reply #1859 on: May 26, 2019, 02:32:56 PM »
http://lmgtfy.com/?q=entitled

Sorry for the OT, couldn't resist. This is a stupid comment rather than a stupid question.

HM! Zat you?

b_lumenkraft

  • Guest
Re: "Stupid" Questions :o
« Reply #1860 on: May 26, 2019, 02:52:43 PM »
I'm so lost here...  :-[

I don't even get the cryptical message.

gerontocrat

  • First-year ice
  • Posts: 6784
    • View Profile
  • Liked: 1686
  • Likes Given: 22
Re: "Stupid" Questions :o
« Reply #1861 on: May 26, 2019, 03:07:40 PM »
Here is my stupid question:
What is CO2e now?
I don't mean the definition, I mean the number. Searching I find an implication that it is still below 500 ppm but will reach it BAU within a decade of 2016:

The latest CO2e figure from NOAA is for 2018, and is 496. That means it is probably just on 500 now (one year after the average for 2018) - more methane, higher CO2 ppm.

Read all about it and NOAA's  ANNUAL GREENHOUSE GAS INDEX (AGGI) at https://www.esrl.noaa.gov/gmd/aggi/aggi.html

At the end of the webpage a simple download if you want the data.
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
"Damn, I wanted to see what happened next" (Epitaph)

petm

  • Grease ice
  • Posts: 675
    • View Profile
  • Liked: 335
  • Likes Given: 27
Re: "Stupid" Questions :o
« Reply #1862 on: May 27, 2019, 12:42:48 AM »
Welcome petm. Perhaps not the best strategy to start off with a cryptic message... but if you have real questions feel free to ask.
Whoops. Tried to post a link to it on the melting season thread but it was too late and got vetoed. @SH nope but close; it was in response to their insanely entitled attitude.

petm

  • Grease ice
  • Posts: 675
    • View Profile
  • Liked: 335
  • Likes Given: 27
Re: "Stupid" Questions :o
« Reply #1863 on: May 27, 2019, 12:49:47 AM »
I'm so lost here...  :-[

I don't even get the cryptical message.
I'm sorry to disappoint you, but to get this straight, HelloMeteor called people assholes, who answered their question in good faith and correctly.
It was about the same thing as your post above.
« Last Edit: May 27, 2019, 12:58:56 AM by petm »

Glen Koehler

  • Frazil ice
  • Posts: 123
    • View Profile
  • Liked: 119
  • Likes Given: 161
Re: "Stupid" Questions :o
« Reply #1864 on: May 27, 2019, 06:04:31 AM »
With dramatic loss of old thick sea ice since 2010, I would expect that PIOMAS Sept. minimum would show stronger downward trend for 2010-2019, but while the long term trend is obvious, the last 10 years have been fairly flat.  Why doesn't loss of old thick ice show up more in PIOMAS Sept. minimum volume?

Jim Hunt

  • Young ice
  • Posts: 4289
    • View Profile
    • The Arctic sea ice Great White Con
  • Liked: 274
  • Likes Given: 27
Re: "Stupid" Questions :o
« Reply #1865 on: May 27, 2019, 11:57:33 AM »
http://lmgtfy.com/?q=entitled

Sorry for the OT, couldn't resist. This is a stupid comment rather than a stupid question.

Can I safely assume that the stupid question refers to the recent antics of GoodbyeMeteor?
« Last Edit: May 27, 2019, 12:32:27 PM by Jim Hunt »
Reality is merely an illusion, albeit a very persistent one - Albert Einstein

Jim Hunt

  • Young ice
  • Posts: 4289
    • View Profile
    • The Arctic sea ice Great White Con
  • Liked: 274
  • Likes Given: 27
Re: "Stupid" Questions :o
« Reply #1866 on: May 27, 2019, 12:01:20 PM »
Why doesn't loss of old thick ice show up more in PIOMAS Sept. minimum volume?

Because thermodynamics means the new ice grows to 2 meters plus thick across the Arctic Basin over every winter?

See the "Slow Transition" thread for more details.
Reality is merely an illusion, albeit a very persistent one - Albert Einstein

Glen Koehler

  • Frazil ice
  • Posts: 123
    • View Profile
  • Liked: 119
  • Likes Given: 161
Re: "Stupid" Questions :o
« Reply #1867 on: May 28, 2019, 02:14:00 AM »
RE #1866 "Because thermodynamics means the new ice grows to 2 meters plus thick across the Arctic Basin over every winter?"

   But that 2 meter new ice growth happens with or without old thick ice.  So it seems that a year with less returning old thick ice from previous year + summer freezing/thickening would result in less volume than an earlier year that had more returning old thick ice and gets the same amount of  summer freezing/thickening.

   The only way I can figure it is that with lower portion of old thick ice, the young ice that replaces it allows faster thickening.  Perhaps the thinner ice cover over water allows more heat loss and thus more thickening, whereas old thick ice is a better insulator and is less dynamic.

oren

  • Young ice
  • Posts: 4532
    • View Profile
  • Liked: 910
  • Likes Given: 1305
Re: "Stupid" Questions :o
« Reply #1868 on: May 28, 2019, 02:59:39 AM »
   But that 2 meter new ice growth happens with or without old thick ice.  So it seems that a year with less returning old thick ice from previous year + summer freezing/thickening would result in less volume than an earlier year that had more returning old thick ice and gets the same amount of  summer freezing/thickening.
And indeed that has been the behavior. When old ice is lost, it is replaced with FYI and the result is a lower winter maximum volume trend. However the winter maximum also depends on the preceding summer minimum and on the effectiveness of autumn freezing. A look at the attached graph (day 120) shows how winter maximum volume has continued on a downward trend, with winter 2017 having an extreme record low. It also shows the correlation between summer minimum (day 260) and the following winter volume. The summer minimum result depends more heavily on weather and is more volatile.

Note: the data includes CAB, Beaufort, Chukchi, ESS, Laptev, Kara, CAA, Greenland Sea - the regions where MYI actually exists.

Note 2: do read the "slow transition" thread, very interesting.

Tor Bejnar

  • Young ice
  • Posts: 3108
    • View Profile
  • Liked: 402
  • Likes Given: 198
Re: "Stupid" Questions :o
« Reply #1869 on: May 28, 2019, 03:01:00 AM »
Thick ice (of any age - rafting, etc. can make thick year old ice) will not grow 2 meters thicker during the winter when nearby thin ice will.  Attached chart shows an example for lake ice - how it grows less as thickness increases.  Ice, basically, is an insulator.

Decades ago, with much of the Arctic covered in MYI (multiyear ice), there was less volume increase in the central Arctic than during recent winters.
Arctic ice is healthy for children and other living things.

Jim Hunt

  • Young ice
  • Posts: 4289
    • View Profile
    • The Arctic sea ice Great White Con
  • Liked: 274
  • Likes Given: 27
Re: "Stupid" Questions :o
« Reply #1870 on: May 28, 2019, 10:14:40 AM »
RE #1866 "Because thermodynamics means the new ice grows to 2 meters plus thick across the Arctic Basin over every winter?"

I've taken the liberty of copying a few recent comments over to a new thread dedicated to this topic. Please see:

"Basic questions about melting physics"
Reality is merely an illusion, albeit a very persistent one - Albert Einstein

Tom_Mazanec

  • Nilas ice
  • Posts: 1708
    • View Profile
    • Planet Mazanec
  • Liked: 392
  • Likes Given: 67
Re: "Stupid" Questions :o
« Reply #1871 on: May 28, 2019, 12:45:30 PM »
According to the Wikipedia infobox, CO2 in the Paleogene period was 500 ppm...which we are now reaching the equivalent of, according to the above.
In the Paleogene, the poles were almost ice free, IIRC.
SHARKS (CROSSED OUT) MONGEESE (SIC) WITH FRICKIN LASER BEAMS ATTACHED TO THEIR HEADS

petm

  • Grease ice
  • Posts: 675
    • View Profile
  • Liked: 335
  • Likes Given: 27
Re: "Stupid" Questions :o
« Reply #1872 on: May 28, 2019, 02:08:31 PM »
In the Paleogene, the poles were almost ice free, IIRC.
Indeed, for most of it: https://en.wikipedia.org/wiki/File:65_Myr_Climate_Change.png

johnm33

  • Nilas ice
  • Posts: 1292
    • View Profile
  • Liked: 86
  • Likes Given: 43
Re: "Stupid" Questions :o
« Reply #1873 on: May 28, 2019, 02:32:26 PM »
According to Tilak there was a permanent springtime climate until very recently.

kassy

  • Grease ice
  • Posts: 861
    • View Profile
  • Liked: 364
  • Likes Given: 378
Re: "Stupid" Questions :o
« Reply #1874 on: May 28, 2019, 04:08:24 PM »
It propounded the theory that North Pole was the original home of Aryans during pre-glacial period which they had to leave due to the ice deluge around 8000 B.C. and had to migrate to the Northern parts of Europe and Asia in search of lands for new settlements.

So this is all BS.
Þetta minnismerki er til vitnis um að við vitum hvað er að gerast og hvað þarf að gera. Aðeins þú veist hvort við gerðum eitthvað.

gerontocrat

  • First-year ice
  • Posts: 6784
    • View Profile
  • Liked: 1686
  • Likes Given: 22
Re: "Stupid" Questions :o
« Reply #1875 on: May 28, 2019, 04:14:02 PM »
It propounded the theory that North Pole was the original home of Aryans during pre-glacial period which they had to leave due to the ice deluge around 8000 B.C. and had to migrate to the Northern parts of Europe and Asia in search of lands for new settlements.

So this is all BS.
Lokmanya Bal Gangadhar Tilak, a mathematician turned astronomer, historian, journalist, philosopher and political leader of India during 1880 to 1920. He propounded the theory that North Pole was the original home of Aryans....balh blah...

Required reading at "The Berghof" on the Obersalzberg, the house of Adolf Hitler.
« Last Edit: May 28, 2019, 04:44:14 PM by gerontocrat »
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
"Damn, I wanted to see what happened next" (Epitaph)

Tor Bejnar

  • Young ice
  • Posts: 3108
    • View Profile
  • Liked: 402
  • Likes Given: 198
Re: "Stupid" Questions :o
« Reply #1876 on: May 28, 2019, 05:14:47 PM »
Good decision!  (Even if some of the early discussion is about "freezing physics"!  :)
RE #1866 "Because thermodynamics means the new ice grows to 2 meters plus thick across the Arctic Basin over every winter?"

I've taken the liberty of copying a few recent comments over to a new thread dedicated to this topic. Please see:

"Basic questions about melting physics"
Arctic ice is healthy for children and other living things.

nanning

  • Nilas ice
  • Posts: 1073
  • 0Kg CO2, 35 KWh/wk,130L H2O/wk, No heating
    • View Profile
  • Liked: 159
  • Likes Given: 6978
Re: "Stupid" Questions :o
« Reply #1877 on: May 28, 2019, 05:24:55 PM »
Can someone please explain what '+ve' and '-ve' mean?
"It is preoccupation with possessions, more than anything else, that prevents us from living freely and nobly" - Bertrand Russell
   Simple: minimize your possessions and be free and kind    It's just a mindset.       Refugees welcome

Jim Hunt

  • Young ice
  • Posts: 4289
    • View Profile
    • The Arctic sea ice Great White Con
  • Liked: 274
  • Likes Given: 27
Re: "Stupid" Questions :o
« Reply #1878 on: May 28, 2019, 05:45:27 PM »
Can someone please explain what '+ve' and '-ve' mean?

Positive and negative I believe.
Reality is merely an illusion, albeit a very persistent one - Albert Einstein

gerontocrat

  • First-year ice
  • Posts: 6784
    • View Profile
  • Liked: 1686
  • Likes Given: 22
Re: "Stupid" Questions :o
« Reply #1879 on: May 28, 2019, 06:03:29 PM »
Can someone please explain what '+ve' and '-ve' mean?

Positive and negative I believe.
And not meaning "good" and "bad", but mathematically, i.e. more of something or less of something. So  a "-ve feedback" of AGW is a something that tends to reduce AGW.
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
"Damn, I wanted to see what happened next" (Epitaph)

nanning

  • Nilas ice
  • Posts: 1073
  • 0Kg CO2, 35 KWh/wk,130L H2O/wk, No heating
    • View Profile
  • Liked: 159
  • Likes Given: 6978
Re: "Stupid" Questions :o
« Reply #1880 on: May 28, 2019, 06:37:12 PM »
Thank you sirs, I posted in the right thread. So "-" = "negati" and "+" = "positi".
"It is preoccupation with possessions, more than anything else, that prevents us from living freely and nobly" - Bertrand Russell
   Simple: minimize your possessions and be free and kind    It's just a mindset.       Refugees welcome

mitch

  • New ice
  • Posts: 87
    • View Profile
  • Liked: 16
  • Likes Given: 0
Re: "Stupid" Questions :o
« Reply #1881 on: May 28, 2019, 07:30:09 PM »
According to the Wikipedia infobox, CO2 in the Paleogene period was 500 ppm...which we are now reaching the equivalent of, according to the above.
In the Paleogene, the poles were almost ice free, IIRC.

The Paleogene is the first part of the Cenozoic, so extends from 65-23 million years ago, so is 42 million years long.  The average CO2 was >1000 ppm until around 34 million years ago (Eocene-Oligocene transition, also known as the Greenhouse-Icehouse transition) and probably dropped below 750 ppmV at that time.  The drop apparently caused the formation of the East Antarctic Ice Sheet.  So, a 500 ppmV average for the Paleogene is probably low.

Pmt111500

  • Nilas ice
  • Posts: 1887
  • Yes, I do not always bicycle
    • View Profile
  • Liked: 96
  • Likes Given: 29
Re: "Stupid" Questions :o
« Reply #1882 on: May 28, 2019, 07:52:13 PM »
According to the Wikipedia infobox, CO2 in the Paleogene period was 500 ppm...which we are now reaching the equivalent of, according to the above.
In the Paleogene, the poles were almost ice free, IIRC.

The Paleogene is the first part of the Cenozoic, so extends from 65-23 million years ago, so is 42 million years long.  The average CO2 was >1000 ppm until around 34 million years ago (Eocene-Oligocene transition, also known as the Greenhouse-Icehouse transition) and probably dropped below 750 ppmV at that time.  The drop apparently caused the formation of the East Antarctic Ice Sheet.  So, a 500 ppmV average for the Paleogene is probably low.

There are plenty oddities in the deep time record of CO2. Partly they can be reconciled by taking the continental drift in account. I Don't remember the configuration in Paleogene but at some point there was an ocean circling the whole equator which would have taken a lot of heat keeping also the colder locations fluid. Maybe it was the eocene.
Cooling the outside by heat pump.

Tor Bejnar

  • Young ice
  • Posts: 3108
    • View Profile
  • Liked: 402
  • Likes Given: 198
Re: "Stupid" Questions :o
« Reply #1883 on: May 28, 2019, 09:10:56 PM »
Read 'all about' the Tethys Sea in Wikipedia (especially under "Oligocene").
Arctic ice is healthy for children and other living things.

Stephan

  • Grease ice
  • Posts: 800
    • View Profile
  • Liked: 266
  • Likes Given: 141
Re: "Stupid" Questions :o
« Reply #1884 on: May 29, 2019, 12:58:50 PM »
I have a "stupid" question concerning microplastic particles in sea water and its influence on the freezing point of water.
The freezing point decreases if ions are dissolved in water (see actual posting about melting physics https://forum.arctic-sea-ice.net/index.php/topic,2709.0.html). The more ions are present, the lower is the freezing point.
What happens if micro- or nanoplastic particles are "dissolved"? As most of them are insoluble in water, it is rather a dispersion. Does this change the freezing point? And into which direction? I also think about bigger particles that may support freezing? And does the change of the freezing point (if there is any) depend on the chemical structure of the plastic material (with or without hydroxyl or carboxylic groups)?
It is too late just to be concerned about Climate Change

Klondike Kat

  • Grease ice
  • Posts: 842
    • View Profile
  • Liked: 47
  • Likes Given: 56
Re: "Stupid" Questions :o
« Reply #1885 on: May 29, 2019, 02:45:44 PM »
I have a "stupid" question concerning microplastic particles in sea water and its influence on the freezing point of water.
The freezing point decreases if ions are dissolved in water (see actual posting about melting physics https://forum.arctic-sea-ice.net/index.php/topic,2709.0.html). The more ions are present, the lower is the freezing point.
What happens if micro- or nanoplastic particles are "dissolved"? As most of them are insoluble in water, it is rather a dispersion. Does this change the freezing point? And into which direction? I also think about bigger particles that may support freezing? And does the change of the freezing point (if there is any) depend on the chemical structure of the plastic material (with or without hydroxyl or carboxylic groups)?

The answer can get quite complicated.  An insoluble particle with have no effect on the freezing point of a pure liquid.  In a solution, dissolved particles could attach to the dispersant, removing them from solution.  In this case, the freezing point would be raised slightly, as the water becomes purer.  Your second question is a definite yes, as polar groups are more likely to attach to dissolved particles than nonpolar groups.  This assumes that the insoluble particle is truly insoluble.  Many substance are slightly soluble, which affects the physical properties.  Then there is the whole question of the specific heat of the dispersant, especially if it floats atop the water.

Sambuccu

  • New ice
  • Posts: 24
    • View Profile
  • Liked: 4
  • Likes Given: 16
Re: "Stupid" Questions :o
« Reply #1886 on: May 30, 2019, 10:58:36 PM »
Hello.

Lurker on ASIF for months, I will start with this section, and with a stupid question :

I never see on this forum DMI volume maps. What is the reason for ? Is it considered unreliable ?


Neven

  • Administrator
  • First-year ice
  • *****
  • Posts: 7209
    • View Profile
    • Arctic Sea Ice Blog
  • Liked: 732
  • Likes Given: 477
Re: "Stupid" Questions :o
« Reply #1887 on: May 30, 2019, 11:00:59 PM »
I never see on this forum DMI volume maps. What is the reason for ? Is it considered unreliable ?

You can sometimes see it pop up on the melting season thread, but yes, it is safe to say that it is considered unreliable.
Il faut comparer, comparer, comparer, et cultiver notre jardin

Sambuccu

  • New ice
  • Posts: 24
    • View Profile
  • Liked: 4
  • Likes Given: 16
Re: "Stupid" Questions :o
« Reply #1888 on: May 30, 2019, 11:16:40 PM »
Thank you for this swift answer.
And too bad for DMI, they have pretty animations and daily updates. But if not reliable...

oren

  • Young ice
  • Posts: 4532
    • View Profile
  • Liked: 910
  • Likes Given: 1305
Re: "Stupid" Questions :o
« Reply #1889 on: May 31, 2019, 08:32:02 AM »
Welcome Sambuccu. DMI volume and thickness is very colorful but unreliable.
One thing that is kind of obvious is that their volume minimum arrives too early - the average graph bottoms in late August, when no refreeze is taking place and while bottom melt still continues until at least mid-September.
All volume and thickness measures are inherently problematic and should be used carefully. But DMI volume should not be used at all.
All of the above is my personal opinion as an ASIF layman.

Sambuccu

  • New ice
  • Posts: 24
    • View Profile
  • Liked: 4
  • Likes Given: 16
Re: "Stupid" Questions :o
« Reply #1890 on: May 31, 2019, 01:51:06 PM »
Thank you Oren.
I know volume measures are problematic.
Problem I have on social medias is people using them to push their agendas : using the fact there is not significant loss in volume on DMI since 2008 to "prove" melting arctic is a scam, for instance...

oren

  • Young ice
  • Posts: 4532
    • View Profile
  • Liked: 910
  • Likes Given: 1305
Re: "Stupid" Questions :o
« Reply #1891 on: May 31, 2019, 05:48:18 PM »
As to that, trolls and deniers will always seem to have the upper hand on social media, as they don't need to stick to any standard of truth or logic. But I think casual readers can sometimes separate between such scum and normal people's posts. Of course, this is OT here...

Sterks

  • Guest
Re: "Stupid" Questions :o
« Reply #1892 on: May 31, 2019, 08:08:39 PM »
Anybody knows where did the AMSR2 daily charts of ice concentration from Uni Hamburg go? I can’t find them anywhere... thanks!

ShortBrutishNasty

  • New ice
  • Posts: 38
    • View Profile
  • Liked: 22
  • Likes Given: 38
Re: "Stupid" Questions :o
« Reply #1893 on: June 01, 2019, 02:24:10 AM »
This is a stupid math question.

I have--hopefully-- attached a .gif of Observed Miami Sea Level Rise From 1880 to 2010.

ASSUMING continued forcings, how can total sea level rise over 1880 level be calculated?  in 2050?  In 2100?

I recognize this is greatly simplified.  I just want to see some basic equations on how a trend line/curve is projected outward.  Don't know if this is calculus or whatever. I just did some pre-calc in school.  Need help here. 

Thanks again.

mr. bob

crandles

  • Young ice
  • Posts: 2547
    • View Profile
  • Liked: 109
  • Likes Given: 47
Re: "Stupid" Questions :o
« Reply #1894 on: June 01, 2019, 12:24:33 PM »
Two points define rate of growth but not acceleration but there is that 228 figure and curve looks smooth, so we can try different curves and see if any matches the 228 figure.

I just opened a spreadsheet, it is easy to play about with the numbers:

I tried various steady growth factors. To get from 0.6 to 4.1 seems to require rate to be about 1.01485 times the previous year. This gets to 238 by 2010. Fairly close.

(A steady increase in the rate going from .6 to 4.1 gets a total of 308. So steady growth factor was much nearer than this.)

That is only two types of curve tried. It is quite possible that a different type of curve could do it. Another possibility is the curve might actually be a compound like 1% growth rate for first x years then 1.9% for next y years .....

Wikipedia says things like
Quote
This network was used, in combination with satellite altimeter data, to establish that global mean sea-level rose 19.5 cm (7.7 in) between 1870 and 2004 at an average rate of about 1.44 mm/yr (1.7 mm/yr during the 20th century).[30] This is an important confirmation of climate change simulations which predicted that sea level rise would accelerate in response to global warming. In Australia, data collected by the Commonwealth Scientific and Industrial Research Organisation (CSIRO) show the current global mean sea level trend to be 3.2 mm (0.13 in) per year, a doubling of the rate during the 20th century.[31][32]

Not too difficult to play around with a spreadsheet to try things out.

Suspect you could get quite different answers by 2100 by assuming different curves. Not quite enough info for me to tie it down. Could try measuring height of line at various points to try to help constrain it but the line looks quite thick and I am therefore not to sure if this will help or if measurement error in this will mean it won't help.

Spreadsheet is probably easier than calculus. Either way need to know details of the curve.

gerontocrat

  • First-year ice
  • Posts: 6784
    • View Profile
  • Liked: 1686
  • Likes Given: 22
Re: "Stupid" Questions :o
« Reply #1895 on: June 01, 2019, 01:00:56 PM »
This is a stupid math question.

I have--hopefully-- attached a .gif of Observed Miami Sea Level Rise From 1880 to 2010.

ASSUMING continued forcings, how can total sea level rise over 1880 level be calculated?  in 2050?  In 2100?

I recognize this is greatly simplified.  I just want to see some basic equations on how a trend line/curve is projected outward.  Don't know if this is calculus or whatever. I just did some pre-calc in school.  Need help here. 

Thanks again.

mr. bob
Last year I had a look at the overall NASA sea level rise data and just plonked it in a spreadsheet and told the spreadsheet to add a trend line. It suggests that on a Business As Usual (BAU) basis the world is looking at another 20 cm of sea level rise by 2050.

BUT
- what is going to happen to Global Heating?
- How much inertia is already built into ice sheet and glacier melting?
etc etc...

And for Miami ? Is the land sinking or rising? (Louisiana is sinking, Scotland is rising)

As the man said - Miami Real Estate? Rent, don't buy. Sell if you can, or accept that definitely one day it will be worthless..
« Last Edit: June 01, 2019, 03:22:02 PM by gerontocrat »
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
"Damn, I wanted to see what happened next" (Epitaph)

binntho

  • Nilas ice
  • Posts: 1095
    • View Profile
  • Liked: 282
  • Likes Given: 76
Re: "Stupid" Questions :o
« Reply #1896 on: June 03, 2019, 10:16:09 AM »
Every now and then I come across somebody explaining lack of the melt ponding they expected with claims that the "new" ice is somehow not able to support or maintain melt ponds. Is there any evidence whatsoever that anybody has come accross that supports such claims?
because a thing is eloquently expressed it should not be taken to be as necessarily true
St. Augustine, Confessions V, 6

wallen

  • New ice
  • Posts: 47
    • View Profile
  • Liked: 7
  • Likes Given: 1
Re: "Stupid" Questions :o
« Reply #1897 on: June 03, 2019, 10:55:42 AM »


And for Miami ? Is the land sinking or rising? (Louisiana is sinking, Scotland is rising)

As the man said - Miami Real Estate? Rent, don't buy. Sell if you can, or accept that definitely one day it will be worthless..

From what I hear Miami is stuffed,even if they build walls and try to pump the water out. Apparently the place is built on porous limestone, so the water table will rise as the sea rises

oren

  • Young ice
  • Posts: 4532
    • View Profile
  • Liked: 910
  • Likes Given: 1305
Re: "Stupid" Questions :o
« Reply #1898 on: June 03, 2019, 11:01:14 AM »
Every now and then I come across somebody explaining lack of the melt ponding they expected with claims that the "new" ice is somehow not able to support or maintain melt ponds. Is there any evidence whatsoever that anybody has come accross that supports such claims?
Not sure if the claim is true, but a partial support for it could be the fact that stable fast ice tends to have more severe melt ponds (deeper color, for longer periods) than normal sea ice. Off the top of my head, this is often evidenced in Kane Basin's Greenland side, in the ESS/Laptev near the coast, and in the CAA.
I don't think it's necessarily new ice, but a bigger, thicker and flatter ice floe can support bigger and deeper melt ponds. The more broken up and pushed around the ice is, I would think it has a lower chance of accumulating large melt ponds.
Also note that only a high concentration of melt ponds would show up on Worldview with the familiar light blue tinge, so little puddles on small floes may not show up at all.

Tom_Mazanec

  • Nilas ice
  • Posts: 1708
    • View Profile
    • Planet Mazanec
  • Liked: 392
  • Likes Given: 67
Re: "Stupid" Questions :o
« Reply #1899 on: June 03, 2019, 01:32:30 PM »
IIRC, AGW can wipe out the arctic and subarctic climate zones, making the poles temperate in wind circulation. Is this correct?
Could AGW create a new equatorial climate zone, a "supertropical" one to coin a term?
SHARKS (CROSSED OUT) MONGEESE (SIC) WITH FRICKIN LASER BEAMS ATTACHED TO THEIR HEADS