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Author Topic: Stupid Questions :o  (Read 187473 times)

Marc

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Re: Stupid Questions :o
« Reply #100 on: August 22, 2013, 02:35:06 AM »
Vergent,

"The air is a significant factor only if it has a dew point that is different from 0C. If it is above 0C condensation is occurring, and one gram of condensation will melt 6.76 grams of ice. Air has a low heat capacity the amount of heat transfer from cooling the air down to zero is insignificant compared  to the condensation dropping the dew point. If the dew point is significantly below zero, then any exposed water will chill rapidly due to evaporation."

Then water temp has much more capacity for heat transfer.

Curious where you stand with what you think is significant driver for causing increased melt (over last decade).  My stand is that it that it's coming from bottom.  I'd say further that I don't think it's the melt, it's the refreeze because the heat in water limits it.  Your understanding of weather/atmosphere is very impressive in discussions above.  What's your best guess?  is it water temp or weather?

Thanks for taking time to respond to me, and thanks for discussion above that was educational.

jdallen

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Re: Stupid Questions :o
« Reply #101 on: August 22, 2013, 08:43:19 AM »
I bet on water temp, by a combination of steadily increased ocean enthalpy reducing the time required for melting to start, combined with the main driver, Seasonal solar heating of arctic surface water.
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Vergent

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Re: Stupid Questions :o
« Reply #102 on: August 22, 2013, 05:30:35 PM »
Marc,

As I see it;

  • increased GHG
  • Decreased ice albedo(algae, permafrost, snow, and ice shelf retreat)
  • Increased Atlantic and Pacific warm water import into the arctic
  • changing weather patterns(Arctic blocking, Dipoles, summer arctic cyclones)

All of these increase the energy in the arctic. The actual melting of the ice is just the second law of thermodynamics. The primary cause is the GHG. The rest are positive feedbacks.

Vergent


Marc

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Re: Stupid Questions :o
« Reply #103 on: August 28, 2013, 12:11:50 AM »
Thanks Vergent,
Not quite the answer I wanted, but can't tell you how much I appreciate your posts.  Your insight is appreciated.  Especially when it's in the middle of arguments between theoreticians and statisticians.  Always great comments.

Thanks

johnm33

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Re: Stupid Questions :o
« Reply #104 on: November 22, 2013, 05:52:21 PM »
Does co2 [+ch4 for that matter] have the same energy retaining effect when dissolved in the ocean, and did we cross a threshold 15 years ago when the oceans began to soak up more heat.

jdallen

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Re: Stupid Questions :o
« Reply #105 on: November 22, 2013, 07:06:01 PM »
Does co2 [+ch4 for that matter] have the same energy retaining effect when dissolved in the ocean, and did we cross a threshold 15 years ago when the oceans began to soak up more heat.

No, it does not.  GHG effects are the result of their being "opaque" to the transmission of certain wavelengths of light, in particular various IR wavelengths.  These line up more or less squarely with the black body emissions at the earths surface, as it absorbs sunlight, and the re-radiates the "heat".

QED, "visible" spectra - that not blocked by GHG's - passes through, gets absorbed, but the re radiated light - considerably increased in wavelength - is blocked and partially trapped.  GHG's do not heat so much as they selectively insulate.

So, once picked up by water, they no longer present a barrier, or affect the *Kinetic* exchange of energy between ocean and atmosphere.
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johnm33

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Re: Stupid Questions :o
« Reply #106 on: December 02, 2013, 12:59:18 PM »
jdallen thanks for that reply, here's another physics type question.
If it were possible to shift a cube of ice [say 1m3 at -10C] instantly from the north pole to 60deg N and it was constrained from moving what effects would be expected?

jdallen

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Re: Stupid Questions :o
« Reply #107 on: December 03, 2013, 10:38:02 AM »
jdallen thanks for that reply, here's another physics type question.
If it were possible to shift a cube of ice [say 1m3 at -10C] instantly from the north pole to 60deg N and it was constrained from moving what effects would be expected?

Sounds like a physics exam question. ;)

As the difference in velocity between the block and ground would be several hundred KPH, I'd say there would be a lot of crushed ice ;)
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Andreas T

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Re: Stupid Questions :o
« Reply #108 on: December 03, 2013, 01:51:46 PM »
If you could explain why you are asking this question and what sort of possible effects you are interested in, John, it would make it easier and more worthwhile for someone to try to answer it.
For example 60 deg latitude covers a lot of different places, with different climate, guessing how quickly that ice would melt obviously depends on that. Locally it would cool and dilute the surface water if placed in the sea. If floating in the sea it would not change mass distribution as far as I know, and sea level only slighly by moving less dense water south and more dense (saltier) water north to take its place.

johnm33

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Re: Stupid Questions :o
« Reply #109 on: December 03, 2013, 04:51:06 PM »
I'm wondering how much energy has to be acquired between the pole and southern greenland, clearly a lot of kinetic energy but how does that translate in terms of temperature. What I want to think about is how much energy is soaked up or shed by the ice as it moves south or north when constrained by the pack.  It may have been better to ask about the imaginary cube going from 60degN to the pole. 

Andreas T

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Re: Stupid Questions :o
« Reply #110 on: December 03, 2013, 09:26:54 PM »
Of course moving floating ice from north to south will mean water of equal mass will take its place in the north and will be displaced in the south. The increase in rotational speed which means a gain in kinetic energy for the ice is balanced by a reduction of the rotational speed and kinetic energy of the water moving north. The change in velocity components in an rectangular coordinate system (in which Newtonian mechanics can be applied) are in balance at any time and momentum is conserved since no external forces (external to earth as a whole) act. During the process of movement kinetic energy would of course be higher for both masses by the north south component of their movement but would be dissipated before coming to rest. This energy would be provided by the sun (in any realistic scenario) and has the same heat input into the earth system whether the movement takes place (heat producing work then dissipated as heat) or not (heat remaining heat).

Andreas T

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Re: Stupid Questions :o
« Reply #111 on: December 04, 2013, 11:50:32 PM »
when ice is removed from land, mass distribution changes:
http://www.nature.com/news/polar-wander-linked-to-climate-change-1.12994



johnm33

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Re: Stupid Questions :o
« Reply #112 on: December 05, 2013, 10:50:00 PM »
Andreas T I had a go at the calcs. myself, with low confidence, I reckon that each m3 of ice needs to soak up about 7mj per kilometer as it moves south, so if there's no sun reaching the surface, a cyclone near the pole should cause anomalous cooling. It makes sense that the bottom currents, heading south, should begin in the greenland sea, since the atlantic waters here surrender their heat to the surface waters/ice flowing south, and when there's little flow through Fram those same atlantic waters penetrate further north to shed their 7mj
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jdallen

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Re: Stupid Questions :o
« Reply #113 on: December 06, 2013, 09:51:24 AM »
Andreas T I had a go at the calcs. myself, with low confidence, I reckon that each m3 of ice needs to soak up about 7mj per kilometer as it moves south, so if there's no sun reaching the surface, a cyclone near the pole should cause anomalous cooling. It makes sense that the bottom currents, heading south, should begin in the greenland sea, since the atlantic waters here surrender their heat to the surface waters/ice flowing south, and when there's little flow through Fram those same atlantic waters penetrate further north to shed their 7mj
  • .
That energy isn't picked up as heat; it's picked up by way of angular momentum.  There isn't a lot of loss to friction.  Contrary-wise, the same mass of water (or air) moving north sheds that momentum.
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johnm33

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Re: Stupid Questions :o
« Reply #114 on: December 13, 2013, 12:28:00 PM »
I can't accept your assertion, the Atlantic waters flowing north shed most of their inertia/kinetic energy in Barents and the Kara. All the graphics and studies i've read show the southbound cold waters gathering in the Greenland sea, with a little input flowing out at depth through Fram and a larger contribution falling off the continental shelf between Svalbard and Norway, but mostly it appears to be 'created' in situ. Also it's implicit in the explanations i've read that energetic content is fully transferable between heat, kinetic and potential energy, so I imagine that somehow it's reflected in the molecular or atomic state of the actual material.
 As the ice passes through Fram and is driven south, it clearly 'wants' to head west [according to accepted theories] but can't because of Greenland, it's also moving away from the axis of rotation on a great arc so i would expect it to be far from equilibrium, and I suspect in energy deficit. The currents heading north have the opposite 'tension' leading to all the complex vortexes along the coast, which serve to refine, differentiate and resolve the potential energies present. Somewhat like the EKE in the Labrador sea.
This still doesn't resolve the question though, does ice[NH] cool as it moves south? and warm as it moves north? that is does it find itself with a potential energy deficit/excess. This would help to make sense of this summers cooling, even as the ocean was exposed when the ice was pushed apart. It would also help explain why the HYCOM CICE so often shows ice growing suddenly thicker when atmospheric conditions don't appear conducive.

jdallen

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Re: Stupid Questions :o
« Reply #115 on: December 14, 2013, 12:22:32 AM »
There is a balance in displacement, otherwise, water & atmosphere volume would stack up at the poles or equator.

The kinetic energy shed or gained is imparted to either atmosphere or ocean, pushing air or water out of the way.  It is not lost to friction.   Air moving north loses momentum to air moving south.  Water moving north loses momentum to water moving south.  As noted above, equal masses are displaced, so  Loss to friction is trivial. Energy is conserved.

Part of your problem is frame of reference.  Any mass moving perpendicular to the axis of a rotating planet, and maintaining near equal angular velocity is in fact undergoing continuous acceleration or deacceleration, depending on direction.  That continuous acceleration is where your energy is going, not to heat. You don't see this from a frame of reference on the ground, as the speed of the moving medium maintains consistent velocity relative to the earths surface, the velocity of which itself changes smoothly with distance from the equator.
« Last Edit: December 14, 2013, 12:35:01 AM by jdallen »
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johnm33

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Re: Stupid Questions :o
« Reply #116 on: December 14, 2013, 01:08:02 PM »
Now we're getting somewhere, it's the energy loss to the continuous acceleration/ gain from continuous deceleration that i wanted to quantify.
No doubt it's all in some kind of dynamic balance, but the processes occur in separate locations to some extent, and where the water is free to writhe to express it's energetic 'discomfort' the ice is stuck on the surface led at the whim of wind and currents. 

Shared Humanity

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Re: Stupid Questions :o
« Reply #117 on: December 14, 2013, 03:55:21 PM »
There is a balance in displacement, otherwise, water & atmosphere volume would stack up at the poles or equator.

The kinetic energy shed or gained is imparted to either atmosphere or ocean, pushing air or water out of the way.  It is not lost to friction.   Air moving north loses momentum to air moving south.  Water moving north loses momentum to water moving south.  As noted above, equal masses are displaced, so  Loss to friction is trivial. Energy is conserved.

Part of your problem is frame of reference.  Any mass moving perpendicular to the axis of a rotating planet, and maintaining near equal angular velocity is in fact undergoing continuous acceleration or deacceleration, depending on direction.  That continuous acceleration is where your energy is going, not to heat. You don't see this from a frame of reference on the ground, as the speed of the moving medium maintains consistent velocity relative to the earths surface, the velocity of which itself changes smoothly with distance from the equator.

Another stupid question........I thought water did stack up at the equator as a result of the earth's rotation? Did I read somewhere that as land ice melts, the sea level rise would be relatively higher as you move towards the equator? 

This is a particularly stupid question as I am asking others whether I read something somewhere. ::)

Andreas T

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Re: Stupid Questions :o
« Reply #118 on: December 14, 2013, 04:15:59 PM »
The main problem with your idea that water cools as it increases its kinetic energy is that this kinetic energy can not come directly from its heat energy. This is the most diffuse form of energy so energy transfer would be from kinetic to heat (through "friction" i.e. dissipation of bulk movement to radom molecular movement) not the other way round. This is basically dictated by the second law of thermodynamics.
That does not mean that movement isn't driven by heat input. This heat input (basically from the sun) produces density and pressure differences in water and air, which produces the forces necessary to accelerate water in any direction.
How this operates in any given location is complex and of course movement of water into the arctic basin along the european land mass must be connected by pressure distibution to outflows of abyssal cold water and low salinity surface water along the greenland coast.

Shared Humanity: yes sea level rise is larger at the equator but remember that there is already a higher elevation of the water level, so additional water will raise levels at equator  and poles proportionally. An added effect is that mass lost from Greenland and Antarctica reduces the gravitational pull towards these masses which also reduces sealevel rise near these costs (assuming all else remaining equal)
The presence of these coasts means water has to have  the same (eastward) rotational speed as the coast or it will be pushed up (increasing pressure at depth) which provides the pressure gradients which accelerate and redirect ocean currents.
Changes in currents and water temperatures are of course a major cause of changes along the east coast of Greenland, but the connection of movement and temperature is not as direct as you seem to think, John.

Shared Humanity

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Re: Stupid Questions :o
« Reply #119 on: January 03, 2014, 06:24:56 PM »
I have been watching Cryosphere Today daily for a couple of years. Over the past couple of weeks, it has been showing fairly significant loss of snow cover over Europe, Scandinavia and eastern Europe in particular. There are now large patches appearing across the  midsection of Russia. This snow cover loss is now showing up in Alaska as well. How accurate are these images and, if accurate, is the current snow cover typical for this time of year?




http://arctic.atmos.uiuc.edu/cryosphere/NEWIMAGES/arctic.seaice.color.000.png

crandles

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Re: Stupid Questions :o
« Reply #120 on: January 03, 2014, 06:39:17 PM »
Rutgers seems to agree on there being little snow in Europe:





http://climate.rutgers.edu/snowcover/chart_daily.php?ui_year=2014&ui_day=2&ui_set=0

but " large patches appearing across the  midsection of Russia" ??

(I take grey areas to mean cloud cover is too thick to see but am not sure that is correct interpretation. So, Russia looks pretty well covered to me in image linked. I also assume it shows extent of snow cover but that there isn't information on thickness - could be just a bit of a ground frost or 3m thick snow.)

Rutgers does have a legend :)
« Last Edit: January 03, 2014, 06:46:28 PM by crandles »

jdallen

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Re: Stupid Questions :o
« Reply #121 on: January 03, 2014, 09:57:40 PM »
I believe the Siberia reports were earlier in December, and limited to southern areas. I can't speak to snow depth, outside of my region (US Pacific NW) which currently has only about 35% of its usual snow pack.
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lanevn

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Re: Stupid Questions :o
« Reply #122 on: February 10, 2014, 07:05:42 AM »
What's happened to arctic part of https://earthdata.nasa.gov/labs/worldview/?

johnm33

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Re: Stupid Questions :o
« Reply #123 on: February 10, 2014, 03:57:17 PM »
Night?

idunno

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Re: Stupid Questions :o
« Reply #124 on: February 10, 2014, 05:23:12 PM »

lanevn

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Re: Stupid Questions :o
« Reply #125 on: February 10, 2014, 05:26:25 PM »
Night?
Oh, .... That were really stupid. Ty.

Theta

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Re: Stupid Questions :o
« Reply #126 on: February 14, 2014, 07:14:54 AM »
I apologise for bringing this up again, but I just wanted to know, since people appear to be getting worried about the Arctic ice, if there was a possibility of the ice continuing on its present track, very little gains and minor losses, and bring about a disastorous melt season with perhaps an early complete melt out of the Arctic Sea Ice altogether regardless of the gains made in the area of volume, I guess with the current diving in extent and area it is likely that the volume of the ice must be deteriorating at this point too.
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jdallen

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Re: Stupid Questions :o
« Reply #127 on: February 14, 2014, 08:38:24 AM »
I apologise for bringing this up again, but I just wanted to know, since people appear to be getting worried about the Arctic ice, if there was a possibility of the ice continuing on its present track, very little gains and minor losses, and bring about a disastorous melt season with perhaps an early complete melt out of the Arctic Sea Ice altogether regardless of the gains made in the area of volume, I guess with the current diving in extent and area it is likely that the volume of the ice must be deteriorating at this point too.
In the current regime in the arctic, there is always the possibility.  I'm cautious about making that kind of prediction however considering my track record over the last few years.  I have learned, that making sweeping predictions are almost certain to result in failure.

A "dive" is not yet certain.  Current events make it more probable, but it is not yet a "given". 

Considering recent years and the vicissitudes of climate events elsewhere on the globe, our ability to predict is still far from certain.  Consider, that current models did not see anything like 2007, much less 2012, before mid century.  We are learning a lot, very fast, and its not particularly comfortable.

Yes, I am concerned, but there is an awful lot that still needs to fall into place before we can conclude that 2014 will be a new record low for ice extent, area and volume.
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Pmt111500

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Re: Stupid Questions :o
« Reply #128 on: February 18, 2014, 06:32:31 AM »
Now this can't be right, can it?
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jdallen

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Re: Stupid Questions :o
« Reply #129 on: February 18, 2014, 08:36:38 AM »
Now this can't be right, can it?


Can't say either way, Pmt.

I have no idea how the curves are being generated, what data they represent, what the hyperbolic curve is tied to, or what any of the dimensions are.  My best guess with any of that is a curve fit to data.  Unfortunately, my experience of curve fitting to unpredictable phenomena is... unpredictable ;)

If you are making broad suggestions that the current ice state is leading to a catastrophe, I'm afraid I've got no way to make that prediction from our current data - only that it is declining far more rapidly than predicted, and does suggest we'll see an "ice free" arctic in the near future.  Outside of that, my crystal ball is still rather opaque.
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Pmt111500

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Re: Stupid Questions :o
« Reply #130 on: February 19, 2014, 03:52:15 AM »
well, yes, there's still thicker and thinner sections in the arctic sea ice so such straightforward extrapolation cannot be correct. and the fact that the form of the curve may well be different. that one isn't even parabolic.
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jdallen

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Re: Stupid Questions :o
« Reply #131 on: February 19, 2014, 06:19:11 AM »
well, yes, there's still thicker and thinner sections in the arctic sea ice so such straightforward extrapolation cannot be correct. and the fact that the form of the curve may well be different. that one isn't even parabolic.

The curve regardless of type presumes a consistent trend.  I'm a long way from thinking that is likely.  I don't think the progression, whether sooner, or later, will be that smooth, and I think "sooner" is a realistic possibility.
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Anne

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Re: Stupid Questions :o
« Reply #132 on: March 23, 2014, 08:32:59 PM »
Here's a really stupid question. Why does a surface sometimes appear as if it's been compressed under a sheet of glass, so that only depressions show? An example here, from Zachariae Isstrøm. I'm guessing it's something to do with digital recording, rather than an actual feature of the landscape.

pikaia

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Re: Stupid Questions :o
« Reply #133 on: March 23, 2014, 11:43:07 PM »
Here's a really stupid question. Why does a surface sometimes appear as if it's been compressed under a sheet of glass, so that only depressions show? An example here, from Zachariae Isstrøm. I'm guessing it's something to do with digital recording, rather than an actual feature of the landscape.


It is an optical illusion. The light is coming from the bottom, but we are used to seeing light coming from the top, so the apparent depressions are actually higher ground. If you rotate the image 180 degrees you will see what I mean.

Anne

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Re: Stupid Questions :o
« Reply #134 on: March 23, 2014, 11:59:34 PM »
Thanks, pikaia. I see what you mean.

But to turn the question upside down: I'm still puzzled - by the uniform flatness of what turns out to be the lower elevation.

crandles

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Re: Stupid Questions :o
« Reply #135 on: March 24, 2014, 12:22:28 AM »
Umm is this too obvious: a lack of elevations below sea level because water finds its way there, and when the sea freezes it is usually pretty flat unless deformed into ridges?

« Last Edit: March 24, 2014, 12:27:46 AM by crandles »

Anne

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« Reply #136 on: March 24, 2014, 12:27:35 AM »
Well, yes, but doesn't it get blown and pushed about? But I guess that is the answer, and that minor deformations don't show because of the scale. (Told you it was a stupid question!)

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Re: Stupid Questions :o
« Reply #137 on: March 24, 2014, 07:43:04 AM »
Anne, my thought was that you may be confused as well by the mist/fog patches that lie on the glacier. I am, and hope for an even more clear day for an even more brilliant image.

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Re: Stupid Questions :o
« Reply #138 on: April 06, 2014, 04:21:54 PM »
This question is not about Arctic Sea Ice per se, but it still is a stupid question so I though this is where it would best fit in.

The reason people are keeping watch on Tropical Cyclone development in the El Nino thread is because we'd expect less of them in the WPAC and more in the EPAC. Is this right?
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jdallen

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« Reply #139 on: April 06, 2014, 07:59:24 PM »
This question is not about Arctic Sea Ice per se, but it still is a stupid question so I though this is where it would best fit in.

The reason people are keeping watch on Tropical Cyclone development in the El Nino thread is because we'd expect less of them in the WPAC and more in the EPAC. Is this right?

Yes and no.  Changes in cyclone development are an effect of the cyclical El Niño/La Niña behavior, so following those can provide a clue as to which direction the momentum of the system is going.  There is also a horrified fascination with the rising intensity and frequency of storms in the western Pacific.  On the close order of two billion people live across the affected region; we have a lot to be concerned about....
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wanderer

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Re: Stupid Questions :o
« Reply #140 on: April 08, 2014, 08:23:53 AM »
Stupid Question #1920:

Why is arctic sea ice volume still growing and sees its max in April, whereas extent and area see their max in March?

icefest

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« Reply #141 on: April 08, 2014, 09:42:06 AM »
Because area depends on the temperatures at the fringes (at it's most southerly extent)
and Volume at the total melt/freeze rate.

This means that the cold north pole might still be getting thicker while spring has arrived in newfoundland.
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Stephen

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« Reply #142 on: April 14, 2014, 01:23:46 AM »
Regarding daily numbers and graphs from the usual suspects (NSIDC, IJIS/JAXA, CT), do any of them take "Sundays off" from their reporting?

I seem to remember that, a few years ago, NSIDC didn't update their numbers on a Sunday.  Just looking at the latest CT area, it does not seem to have been updated for 48 hours.

And could someone provide a list of when the numbers are typically updated for each site (in GMT).
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Jim Hunt

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Re: Stupid Questions :o
« Reply #143 on: April 14, 2014, 09:44:57 AM »
And could someone provide a list of when the numbers are typically updated for each site (in GMT).


I'm intrigued to know why you ask these questions Stephen? As a partial answer, keep a close eye on the IJIS/JAXA and Area and Extent threads.

The JAXA numbers seem to come out when they're at work in Japan (i.e. early morning UTC). NSIDC/CT numbers seem to come out when they're at work in Colorado. (i.e. mid/late afternoon UTC)
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Stephen

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Re: Stupid Questions :o
« Reply #144 on: April 14, 2014, 10:16:05 AM »
And could someone provide a list of when the numbers are typically updated for each site (in GMT).


I'm intrigued to know why you ask these questions Stephen? As a partial answer, keep a close eye on the IJIS/JAXA and Area and Extent threads.

The JAXA numbers seem to come out when they're at work in Japan (i.e. early morning UTC). NSIDC/CT numbers seem to come out when they're at work in Colorado. (i.e. mid/late afternoon UTC)


No particular good reason, just curious. I do check those threads just after the sites.
I'm in the GMT +10 timezone and they are usually updated when I check in the morning.
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The ice was all around:
It crack'd and growl'd, and roar'd and howl'd,   
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Short wavelength vs long wavelength
« Reply #145 on: April 21, 2014, 12:40:45 AM »
Question for the physics inclined folks:  I know that light comes into the atmosphere from the sun in a "short wavelength".......and when hits the earth and is radiated back out towards space in "long wavelengths" (generally).

BUT.......my question is this:  If sunlight comes into the atmosphere from the sun and hits "white snow" (ie relatively "pure snow" and not snow with coal dust...or other dark particles).......is it REFLECTED back out of the atmosphere via SHORT WAVELENGTH.......OR is it still radiated back out in long wavelenth?

Thanks in advance........
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Chuck Yokota

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Re: Stupid Questions :o
« Reply #146 on: April 21, 2014, 02:55:20 AM »
Buddy,
The reflected sunlight stays in the same short wavelengths as it arrived.  The fraction of sunlight reflected by the Earth is its albedo, which is accounted for separately from the energy that is absorbed and re-radiated.  It is only when the sunlight is absorbed by matter that it is radiated back out in the long wavelengths. 

icefest

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Re: Stupid Questions :o
« Reply #147 on: April 24, 2014, 05:38:12 PM »
Next stupid question:

RMM (Real-time Multivariate MJO) Index charts
How do I read these charts?
Other than saying "Yep, that's definitely a chart" there's not much else I can do.


 
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opensheart

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Re: Stupid Questions :o
« Reply #148 on: April 24, 2014, 06:49:27 PM »
I don't really understand it either.

From what I can guess at, it kinda maps the Equator of the Earth.   The different sections are different parts of the Earth the Equator goes througth.    Section 1 begins with Longtitude 0 in Africa.  then as you move east you leave Africa and come to the Indian Ocean,  Which is the bottom two sections of the graph.   Then as you leave the Indian Ocean, you come to Indonesia and various Islands.   This is the right sections of the graph.   then when you clear the Islands you come to wide open ocean, which is the top sections of the graph.   
But here my idea breaks down, for if the top seconds are just the Western Pacific, then the last section, section 8, would have to cover the Eastern Pacific, South America, and the South Atlantic all the way back to Long 0 in Africa in one small section.  That's almost half the planet.   so my guess must be wrong.

I gather that the closer a point is to the center, the weaker 'it' is,  and the farther from the center the stronger 'it' is.   But I don't know what the center circle is suppose to represent.  Some sort of threshold perhaps?

Clarification and explaination from those who know would be appreciated.

Pmt111500

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Re: Stupid Questions :o
« Reply #149 on: April 24, 2014, 06:58:59 PM »
No help from me either... other than it appears this plots MJO around the globe though it usually is present only in Pacific and Indian Oceans. In Atlantic Ocean, so I've read, the pattern usually breaks down since North-South movements of ocean water are that much stronger here...
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