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John_The_Elder

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #150 on: April 24, 2014, 06:59:50 PM »
Hi folks,

Here is a link that describes the Madden Julian Oscillation (MJO)

http://www.cpc.ncep.noaa.gov/products/precip/CWlink/MJO/mjo.shtml#educational%20material

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Bruce Steele

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #151 on: April 24, 2014, 07:45:02 PM »
Here is a animation that shows rain intensity . It also shows a clocklike blue pie-slice that corresponds to the MJO index chart we are used to seeing. So when rain intensity is highest in the Indian Ocean the pie-slice points 8 o' clock as the pie- slice moves counterclockwise to 4 o'clock the rain intensity moves eastward over Indonesea  12 o'clock enters Pacific and at 3 o'clock the Western Pacific. Because it is an occilation it moves back the the Indian Ocean rather than continuing into the Eastern Pacific or Atlantic.

 http://envam1.env.uea.ac.uk/mjo.html

icefest

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #152 on: April 24, 2014, 10:27:27 PM »
I think i understand it now. Thanks to everyone that  answered!
« Last Edit: April 25, 2014, 06:47:50 AM by icefest »
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ktonine

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #153 on: April 25, 2014, 06:41:13 AM »
The original paper detailing the time series is An All-Season Real-Time Multivariate MJO Index: Development of an Index for Monitoring and Prediction , MATTHEW C. WHEELER AND HARRY H. HENDON, Bureau of Meteorology Research Centre, Melbourne, Australia (2004, American Meteorological Society).

Pmt111500

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #154 on: April 25, 2014, 07:29:17 AM »
ok, thanks, Bruce Steele, and others, so, to make it certain, the image in question shows a two week reversal of the general eastward progression of MJO in the beginning of the february, with associated waning (almost disappearing) of the oscillation?

seattlerocks

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #155 on: April 25, 2014, 11:52:42 AM »
Why fast ice is called "fast"? To me it seems pretty slow

icefest

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #156 on: April 25, 2014, 11:58:11 AM »
Because it's stuck 'fast' to the land.

Same word root as "fastener".



Quote
Old English fæst "firmly fixed, steadfast, secure, enclosed," probably from Proto-Germanic *fastuz (cognates: Old Frisian fest, Old Norse fastr, Dutch vast, German fest), from PIE root *past- "firm" (source of Sanskrit pastyam "dwelling place").
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Anne

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #157 on: April 25, 2014, 12:23:58 PM »
"Fast" is one of those words like "cleave" and "sanction", which can mean opposite things.

theoldinsane

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #158 on: April 25, 2014, 07:25:17 PM »
I think it comes from the Danish "fast". Remember that Greenland belongs to Denmark. It is almost the same in Swedish.

Google translation from Swedish:

solid, fixed, rigid, firm, settled, permanent, immovable, unblinking, unshaken

choose what you like the best  8)


Espen

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #159 on: April 25, 2014, 08:16:08 PM »
It is very common in the English language: To fasten something?

And then in Scandinavian it means fast= solid / together.

Many words that describe the form of  ice, snow etc. are Norwegian or Swedish, and not Danish the only Danish word to describe a form of ice, I can think of, is Isstrøm, instead of Bræ/  Bre (Norwegian) or Gletscher (German).

Even the word Slalom is Norwegian and mean the opposite of downhill.
« Last Edit: April 25, 2014, 08:31:11 PM by Espen »
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Espen

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #160 on: April 25, 2014, 09:43:27 PM »
Some more words comes to mind:
Rucksack= Norwegian
Smorgasbord= Swedish
Beck= Scandinavian
Ski=Norwegian
Dublin= Black River / Pool (Vikings)
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Anne

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #161 on: April 25, 2014, 09:48:39 PM »
Indeed, and you'd say "hold fast to that notion."

Lots of loan words here from Scandinavian languages. Berserk, maelstrom, ransack... Few English speakers seem to know their origin.

Espen

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #162 on: April 25, 2014, 10:13:02 PM »
Indeed, and you'd say "hold fast to that notion."

Lots of loan words here from Scandinavian languages. Berserk, maelstrom, ransack... Few English speakers seem to know their origin.
That said Scandinavian is basically German!
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theoldinsane

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #163 on: April 25, 2014, 10:59:56 PM »
BTW

Iceberg

What about the "berg"? Well, in Swedish and Norwegian a berg is a rock or mountain. But in Danish it is bjerg. Maybe to difficult to pronounce in English I suppose.

Espen

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #164 on: April 25, 2014, 11:15:30 PM »
And in German gebirge, and in in Danish a real berg don't exist, the maximum height in Denmark is +/- 180 meters.
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icefest

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #165 on: April 25, 2014, 11:18:53 PM »
Sea ice forums, where a question about sea ice is turned into an etymological debate...

I'd like to point out that in this case fast came via germanic from the proto indo european "past".
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seattlerocks

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #166 on: April 26, 2014, 01:03:16 AM »
Thanks to Icefest, and to all of you for the  linguistic discussion, I did not know about the sort of opposite meanings of "fast". Despite my nickname, English is not my native language so I appreciate it.

ChasingIce

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #167 on: April 26, 2014, 06:10:46 AM »
If you had to pick an oceanic pattern, which oceanic region would you pick to predict the future of the globe?

Pmt111500

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #168 on: April 26, 2014, 08:49:45 AM »
If you had to pick an oceanic pattern, which oceanic region would you pick to predict the future of the globe?
My answer (there are couple others that are relevant too, imo, like the amount of deeper water exchange between North and South Pacific see f.e. http://link.springer.com/article/10.1007%2Fs00382-014-2147-z ), would be this one :
some recent papers:
http://www.brest.ird.fr/personnel/ppenven/publications/beal_nature2011.pdf
http://www.ocean-sci.net/9/773/2013/os-9-773-2013.pdf
http://www.researchgate.net/publication/256495054_Agulhas_salt-leakage_oscillations_during_abrupt_climate_changes_of_the_Late_Pleistocene/file/3deec5231b5e4f0575.pdf
enlarged table on paleorecord here showing there's correlation with abrupt events in climate history and Agulhas Leakage. Whether Agulhas Leak amounts are leading the abrupt changes or come closely after them I can't say but clearly there's a connection.
http://www.nature.com/nature/journal/v472/n7344/fig_tab/nature09983_F4.html
« Last Edit: May 07, 2014, 07:31:53 AM by Pmt111500 »

E.

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #169 on: May 07, 2014, 02:12:55 AM »
Can anyone explain to me the CVFS2 data that show no August anomaly in Arctic sea ice?  Joe Bastardi is trumpeting it on WUWT as the beginning of the end of sea ice decline.  What is the model seeing that the experts here are not, and that is causing this result?

Also as to the "fast" discussion: there is a beautiful short chapter of Moby Dick called "Fast Fish and Loose Fish" that discusses the 19th Century legal test for determining who owns the whale you just speared if there is already someone else's spear in it.  It's fascinating.

Csnavywx

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #170 on: May 07, 2014, 12:25:28 PM »
Can anyone explain to me the CVFS2 data that show no August anomaly in Arctic sea ice?  Joe Bastardi is trumpeting it on WUWT as the beginning of the end of sea ice decline.  What is the model seeing that the experts here are not, and that is causing this result?

Also as to the "fast" discussion: there is a beautiful short chapter of Moby Dick called "Fast Fish and Loose Fish" that discusses the 19th Century legal test for determining who owns the whale you just speared if there is already someone else's spear in it.  It's fascinating.

The CFS is notoriously bad at sea ice prediction. Bastardi is trumpeting it because that's about all he has left.

Neven

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #171 on: May 07, 2014, 01:48:14 PM »
Can anyone explain to me the CVFS2 data that show no August anomaly in Arctic sea ice?  Joe Bastardi is trumpeting it on WUWT as the beginning of the end of sea ice decline.  What is the model seeing that the experts here are not, and that is causing this result?

Also check comments by Nick Stokes and Steve Mosher below the WUWT article.
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epiphyte

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #172 on: May 14, 2014, 08:41:23 PM »
Hi all,

Neven recently posted a current DMI 2m temp SAT map showing pretty much uniform 0 degrees C temp everywhere there is ice...

https://lh3.googleusercontent.com/-0XYWv18zjlw/U3MRGwvYs_I/AAAAAAAABrw/16BKP3giTjY/s446/temp_latest.big.png

...Am I correct in assuming that an air temp of 0C right above ice can be an indication that the humidity is high enough for moisture to be condensing on the ice, thereby warming it?

...could it even be the case that when the air temp is _above_ 0C a short distance above ice, it might be because the humidity is too low to permit much heat to be transferred between the two?

If there's any truth to either or both of the above, would a uniform 0 degree temp across the whole arctic simply be an indication that there is sufficient surface insolation to raise the temperature to the point where where the ice is getting warmer, and the air is being cooled by either melting ice, or condensation onto sub-zero ice?

If dewpoint is as significant as it would seem to be in this situation, is there any direct or indirect way of knowing what it is at any given point using the available observations, etc?




LRC1962

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #173 on: May 21, 2014, 06:04:42 AM »
From CBC blog:
Quote
Blustery Weather In The High Arctic...
By Christy Climenhaga on May 15, 2014 2:12 PM

    A wind warning is now in effect for Grise Fiord NU. Winds have been gusting to 110 km/h today and will remain strong until this evening.
    Along with the windy weather, snowfall is present in the area, causing blowing snow and near blizzard conditions.
    Windy weather and snow is also in the Kitikmeot region of Nunavut, which is expected to continue tomorrow.
    Cloudy weather is in the forecast for the Kivalliq region, with light wet flurries in Baker Lake.
    Temperatures in the area will remain just above freezing.
    After snowfall last night in Iqaluit, things should remain dry for the day tomorrow.
    Further north on Baffin Island, things will remain overcast and flurries are in the forecast.


NWT OUTLOOK

    Light rain/snow will remain for the Mackenzie Delta tomorrow, with temperatures rising to 4 degrees.
    Rain showers are also expected in the Sahtu tomorrow while the south will remain clear.
    Along with the clear weather, the south will see warm temperatures in the teens or near 20 degrees in the Dehcho.


YUKON OUTLOOK

    Stray cloud cover is expected through most of the Yukon tomorrow with showers in the forecast for Old Crow.
    Temperatures will be warm in the territory, in the high teens in the south, and near 20 degrees in Dawson City.
According to this 2 things were happening that day Very high winds wet snow (at least in the Baffin Island area. I am no ice expert, but I would not think either of those conditions would be healthy for ice, and you got both.
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LRC1962

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #174 on: May 21, 2014, 07:20:01 AM »
A question: How can you have relative humidity of over 100%?
Googling that added more to my confusion as I got everything from max of 100% to yes in a supersaturation case which can only last a very short time to - depending on if you are above or below freezing on land or over ice depends open how you take the measurements and what formula you use.
Liverpool Bay, Northwest Territories, Canada

Quote
latitude: 69-36N, longitude: 130-54W, elevation: 102 m

METAR: CWLI 210500Z AUTO 03016KT M06/ A3012 RMK SLP212
Time: 23:44 (05:44 UTC)
Current weather observation
The report was made 44 minutes ago, at 05:00 UTC 
Wind 16 kt from north/northeast
Temperature -6°C
Humidity 157%
Pressure 1020 hPa
Visibility
« Last Edit: May 21, 2014, 07:46:07 AM by LRC1962 »
"All truth passes through three stages: First, it is ridiculed; Second,  it is violently opposed; and Third, it is accepted as self-evident."
       - Arthur Schopenhauer

LRC1962

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #175 on: May 21, 2014, 07:52:07 AM »
Probably asked and answered a hundred times already: How do you post images on this forum?
I do understand it must be from somewhere online. I do think it must end with the right type of file. So with all the security storage share sites have now, which sites are the easiest to upload to that you then can share on this forum?
"All truth passes through three stages: First, it is ridiculed; Second,  it is violently opposed; and Third, it is accepted as self-evident."
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icefest

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #176 on: May 21, 2014, 08:53:18 AM »
You can upload via attachments directly to this website:






I personally prefer www.puu.sh
You install an app on your pc and then you can press <Ctrl + 4> and draw a box on your screen.
The program then uploads the images and puts the URL in your clipboard so you can just paste it in here like this:
Code: [Select]
[img]http://puu.sh/8UUri.png[/img]
-icefest
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crash

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #177 on: May 21, 2014, 07:58:05 PM »
I have a stupid question.  Can one think of "cold" (or maybe "cold air") as an entity that is conserved? E.g., if the U.S. Midwest is having an extra-cold winter, does that mean we have "more" cold air than usual, and so some other place has LESS cold air than usual, because the total amount of cold air remains roughly constant?  Is this why Siberia had a warmer winter this past year?

Or could every place  in the world have "more" cold air than normal (here I am assuming no volcanic activity, etc.)?

(I guess with the understanding that the total "mass" of cold air is decreasing from year to year due to AGW?)

Thanks

Rubikscube

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #178 on: May 21, 2014, 10:09:04 PM »
I have a stupid question.  Can one think of "cold" (or maybe "cold air") as an entity that is conserved? E.g., if the U.S. Midwest is having an extra-cold winter, does that mean we have "more" cold air than usual, and so some other place has LESS cold air than usual, because the total amount of cold air remains roughly constant?  Is this why Siberia had a warmer winter this past year?

Or could every place  in the world have "more" cold air than normal (here I am assuming no volcanic activity, etc.)?

(I guess with the understanding that the total "mass" of cold air is decreasing from year to year due to AGW?)

Thanks

In some way you are right, however, in physics one never speaks of the amount of cold in a system, one rather speak of the amount of thermal energy in a system. Cold usually refers to a lack of this thermal energy, or alternatively a lack of energy transfer between to systems (a process generally known as heating). So if the US Midwest has an extra cold winter, it means that there is less thermal energy in the Midwest, usually because less energy than usual has been transfered to the Midwest from elsewhere.

Global warming is really about energy accumulating in the Earths oceans and lower atmosphere because GHGs prevent the Earth from radiating as much energy into space as it absorbes from the sun, which is needed to keep the temperature stable.

ktonine

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #179 on: May 22, 2014, 02:02:35 AM »
I have a stupid question.  Can one think of "cold" (or maybe "cold air") as an entity that is conserved?

(I guess with the understanding that the total "mass" of cold air is decreasing from year to year due to AGW?)

Thanks

Crash - you basically answered (correctly) your own question :)

But, as Rubikscube points out, in a sense while there is no 'conservation of temperature'  if one part of the globe is experiencing significantly cold temperatures there is a good chance another  part is significantly warm and vice versa.  After all, the global mean is not changing much - usually a few hundredths of a degree per month.  Likewise the same can be assumed for precipitation.  Unfortunately, GW predicts that these extremes will become more commonplace.

Pmt111500

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #180 on: May 22, 2014, 12:12:03 PM »
my, not trained in physics, answer would be something like: in a sense the universe pool of cold that is the afterglow of big bang is the most conserved entity in the history of the universe. The increase of entropy over time takes care of that. Looking closer, only troposphere, one might argue that there are pools of heat and cold which both try to approach the grey-body temperature of TOA. in a sense they are also conserved wrt equilibrium surface temperature of the planet (heat flow at equilibrium will be such and such in tropics and in the poles). Someone better at physics may see something to correct here.

crash

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #181 on: May 22, 2014, 08:59:29 PM »
Thanks all, this was helpful. 

LRC1962

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #182 on: May 26, 2014, 03:56:48 AM »
Based on what I have picked up watching educational programs only. heat always wants to go to cold. Much like water action in regards to osmosis. Weather systems are what keeps cold and heat separate, or mixes them up, that all depends upon what the weather system is doing at the time.
In regards to heat, we do know approximately how much energy/heat is around on/in the earth over a specific period of time. Therefor if we know that energy level on earth are going up and we have an unusual cold spot, then we know somewhere else there is more heat. That is the tricky thing. For example the average world wide temps have been more or less stable over the last 10 yrs or so. We also know that energy levels (radiation coming in over radiation leaving) have been rising over the same period of time. That means somewhere that heat is rising temperatures where we normally do not record. Best guess is deep ocean. that effects ocean currents and when it does eventually come to the surface again the ocean temps will start rising fast and that will then cause air temps to rise.
As the Arctic is concerned it has the nick name among some as the AC unit of the world. Once the ice is gone that AC unit is broken. Do I need to go farther?
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Pmt111500

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #183 on: May 26, 2014, 06:47:15 AM »
As the Arctic is concerned it has the nick name among some as the AC unit of the world. Once the ice is gone that AC unit is broken. Do I need to go farther?

Well, Arctic is 'the AC unit of northern hemisphere', if you want to be more scientific about it.

It's not yet totally broken, though, works at reduced capacity. This is such a nice analogy that some numbers might be easily calculated.:
As there's ice also in Greenland (c. 1,7 Mkm2) you could state that the AC unit of northern hemisphere has lost (1-10,7/12,2Mkm2) = c. 12,5% of it's power in 30 years (from yearly means of CT SIA) or that the cooling capacity of the AC unit varies at (estimates) 95%(winter) - 65% (summer) of nominal (100%) value of 1980. once the sea ice is gone this unit works at 10% of nominal level (only Greenland Ice Sheet left, which is getting darker by the years.). I don't know where we could buy a new unit. My hunch is that this reduced power of arctic AC unit is one if not the main reason for wider weather fluctuations in NH projected by the climate models, but I've not seen studies done where this would have been spelled out clearly. It's possible that this is such a basic conclusion that no one has seen the trouble of getting it through the peer-review system.
« Last Edit: May 26, 2014, 06:57:18 AM by Pmt111500 »

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #184 on: May 29, 2014, 02:25:17 PM »
A question: How can you have relative humidity of over 100%?
Googling that added more to my confusion as I got everything from max of 100% to yes in a supersaturation case which can only last a very short time to - depending on if you are above or below freezing on land or over ice depends open how you take the measurements and what formula you use.
Liverpool Bay, Northwest Territories, Canada

Quote
latitude: 69-36N, longitude: 130-54W, elevation: 102 m

METAR: CWLI 210500Z AUTO 03016KT M06/ A3012 RMK SLP212
Time: 23:44 (05:44 UTC)
Current weather observation
The report was made 44 minutes ago, at 05:00 UTC 
Wind 16 kt from north/northeast
Temperature -6°C
Humidity 157%
Pressure 1020 hPa
Visibility
It is worth remembering that the saturation humidity with respect to ice is different than that compared to water.

Thus you can have a situation which is super-saturated with respect to ice and undersaturated with respect to water, so that, for example, water droplets will evaporate and water vapour will deposit onto ice crystals. This is important in cloud microphysics and produces effects such as riming.

Given that you have a temperature at the station of below freezing, my guess would be that it is giving you the relative humidity with respect to ice, but that there is a humidity source from liquid water that is keeping the humidity higher than would otherwise be possible.

k largo

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #185 on: May 30, 2014, 06:29:39 PM »
A question: How can you have relative humidity of over 100%?
Googling that added more to my confusion as I got everything from max of 100% to yes in a supersaturation case which can only last a very short time to - depending on if you are above or below freezing on land or over ice depends open how you take the measurements and what formula you use.
Liverpool Bay, Northwest Territories, Canada

Quote
latitude: 69-36N, longitude: 130-54W, elevation: 102 m

METAR: CWLI 210500Z AUTO 03016KT M06/ A3012 RMK SLP212
Time: 23:44 (05:44 UTC)
Current weather observation
The report was made 44 minutes ago, at 05:00 UTC 
Wind 16 kt from north/northeast
Temperature -6°C
Humidity 157%
Pressure 1020 hPa
Visibility

It is a good question, but the answer is quite  simple.

The METAR you quote has no Dew Point Temperature (DP). The Temperature is given as -6/  and there is a space where the DP would be.
The program which decoded the METAR has read the blank space as zero and therefore gives a nonsense value.
By definition Relative Humidity cannot be over 100% except as you mention in isolated cases of super saturation.  Even over ice the RH cannot be over 100%, but it is true that the saturation vapour pressure associated with ice (usually in clouds) can be different than with air. That doesn’t change the fact that RH can’t be greater than 100%, it just means as you also wrote, the way of calculating it is different. If the subzero temperature of the ice is not taken into account then values of over 100% are given but in fact the calculation should be done differently so that the value will be 100% or lower. See: http://www.mbw.ch/papers/RH_WMO.pdf

In regard to Liverpool Bay and other stations, there may not be a humidity sensor and therefore the reading is blank. Remarkably many web sites giving those observations take that as zero.

See the 24 hour trend  for CWLI here: http://www.checkwx.com/weather/CWLI
The Dewpoint temperature is reported as an unchanged 32F all day.
« Last Edit: May 30, 2014, 06:34:52 PM by k largo »

Theta

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #186 on: June 04, 2014, 11:55:55 AM »
Since there is a chance of the East Siberian Shelf being devoid of ice this year, what are the implications for Methane release in this regard. Are we likely to see releases that echo the worst case Climate Change scenarios?
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Gray-Wolf

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #187 on: June 04, 2014, 12:09:24 PM »
We have a comedy quiz in the UK known as QI (Quite interesting) and , on occasion, we have a 'nobody knows!' answer and I think this falls into that category Theta?

After the international study in 2011(?) that brought us the info that the 'chimney' features had grown ten fold from the previous year I have come across very little in the way of papers/data?

I cannot believe that an international team , spurred on by ships capt.s reporting 'boiling oceans', back in 2011 just abandon their studies?

Maybe in this climate of climate disinformation they are making sure that they have all the data ( esp. if bad news) checked and correctly interpreted before we get a release?

Such early open water must have impact on water column temps though?
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Theta

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #188 on: June 04, 2014, 12:39:58 PM »
We have a comedy quiz in the UK known as QI (Quite interesting) and , on occasion, we have a 'nobody knows!' answer and I think this falls into that category Theta?

After the international study in 2011(?) that brought us the info that the 'chimney' features had grown ten fold from the previous year I have come across very little in the way of papers/data?

I cannot believe that an international team , spurred on by ships capt.s reporting 'boiling oceans', back in 2011 just abandon their studies?

Maybe in this climate of climate disinformation they are making sure that they have all the data ( esp. if bad news) checked and correctly interpreted before we get a release?

Such early open water must have impact on water column temps though?

Thanks Gray, the fact that nobody knows makes me glad I put my question in this thread rather than derailing everyone's observation of the ongoing Sea Ice Melt.

Overall, it is also quite frightening that we don't even have to lose much ice in order for the clathrate gun to fire right into the heart of earth's ecosystem.
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JayW

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #189 on: June 04, 2014, 12:53:28 PM »
Sorry if this has been discussed, but I had a couple questions/thoughts.

This is only my second ice watching season, so it's impossible for me to compare to others years.  However, I have seen others comment on the poor state of the ice, wether it be fractured, or slushy, or rotten.  My question is, if the ice is becoming more "porous", wouldn't that make it more difficult for melt ponds to form? 

My second is more of a thought.  Where I live, lakes and ponds freeze for 3-5 months of the year, with thickness that can reach 1 meter in the more northern areas.  I have done a fair amount of ice fishing, and with lakes all around me, have watched "ice out" on many occasions.  I'm not sure how much of what I observe when freshwater lakes melt can be applied to arctic ice melt, but one thing sucks in my mind.  It has to do with wind, and it's effects on the difference between temperature at 2 meters and the air that "hugs" the ice.  When standing on the ice on a relatively warm day without any wind, your feet can get quite cold because of the cold that seems to suck right on the ice.  Yet, on cooler days with wind, your feet wouldn't feel as cold because that frigid cold that seems to radiate to your feet is scoured away.
Hope I worded that right.

My point is that wind is extremely important in the melting process of our lakes.  Coupled with elevated dew points,  the wind can really eat ice, even at temps just above freezing.  Also, one would be surprise how much "grip" smooth ice can get on the wind.  I have seen light, but persistent breezes pushing the ice around surprisingly easily once it begins to melt away from shore. 

Like I sad though, perhaps this has no qualitative value in regards to arctic ice.  :)

Edit: oops thought I was in the drift, deformation, and fracture thread.  It's probably a stupid question any way.  :P
« Last Edit: June 19, 2014, 05:33:08 AM by JayW »
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DoomInTheUK

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #190 on: June 05, 2014, 01:46:16 PM »
Jay,

Not really a stupid question, more one of scale of view.

Yes the ice can have changes in it's surface, rippling, snow cover, be more porous etc. This will have localised impacts for the ice's strength, how well melt-ponds form and how long they will last.

Porous ice is weak ice and will break more easily, but that still may leave chunks 100's or 1000's meters across. Each one is large enough to hold multiple melt ponds. The porous ice below a melt pond will allow it to drain quicker by opening a hole through, and so this warm water gets a quicker path through to the underside.

Stress, melt ponding and surface changes can't be taken in isolation nor can they be viewed with a given timeline. Each attribute effects the other. Ice behaves more like a slow fluid than a flexible solid.

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #191 on: June 09, 2014, 06:19:10 PM »
I have a stupid question.  When you go to the DMI Centre for Ocean Ice, and look at the historical "Daily Mean Temperatures for 80N":

http://ocean.dmi.dk/arctic/meant80n.uk.php

The winters seem to be a lot more "spiky", i.e. departures from the mean are often 10 degrees K +/-.  However during the summer, departures from the mean are much smaller.  Why is this? 

I suppose I can guess that even during the summer, temps don't get much above freezing because, well, there's mostly just ice at 80N and "above", even with the ice coverage trending downward. 

Still,  the  area N of 80N is not covered in ice during June and July (right?), so I would expect some spikes up to maybe 280 Kelvin here and there.  Is the reason that water is most of what's N of 80N, and the water is going to stay a few degrees above freezing, and therefore limits the temps to around 275K for the most part? 

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #192 on: June 09, 2014, 07:28:32 PM »
It is June now and it is almost all ice covered with maybe a couple of tiny exceptions. Even at the minimum in September I would suggest at least 70% of area remains ice covered (including melt ponds) with temp close to 0C. Most of the remaining water will have ice pretty close so that water doesn't get much above melting point -1.5C. That will only leave about 10% of the area where the water can warm to 2 or 3C. So surface temperature has probably remained negative so far. 2m and above can be warmer due to winds from warmer more southerly locations.

Summer temperatures are declining slightly if you flick through quite a few years. Probably due to larger areas near -1.5C for melting point of sea water rather than 0C for a melt pond of low salinity water.

Temps in winter can vary a lot as winds can circulate around pole and get very cold or warm winds can bring in some heat from a warmer direction (Atlantic or Pacific).

In summer the latent heat required to melt ice keeps the surface near 0 or -1.5 and that soon cools surface winds.
« Last Edit: June 09, 2014, 07:34:31 PM by crandles »

Andreas T

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #193 on: June 15, 2014, 08:10:20 PM »
another effect which contributes to those rapid changes in winter is that the lowest temperatures occur when clear skies allow surfaces to cool by radiating heat out into space. This means a very thin surface layer is affected by the cooling. The surface is often covered in snow, which as a good insulation has a steep temperature gradient, much of its depth cools much more slowly than the surface. Air which is cooled by the surface stays in contact with the surface because it increases its density so relatively small volumes (and heat capacities) of snow and air are affected by cooling so temperature drops are rapid. When conditions change, either by advection of warmer air or by clouds reducing the cooling these relatively thin layers of air and snow warm up quite quickly.
One place where this can be observed is in the temperature profiles measured by buoys where temperatures drop at the surface well below those of the bulk of the ice only to return soon to something close to the ice temperature.

Anne

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #194 on: June 19, 2014, 05:04:00 AM »
This is a REALLY stupid question. It deserves to get me expelled.
Elsewhere on the forum there is a fair bit of cognitive dissonance over the stories told by NSDIC and so on compared with weather reports. There aren't enough buoys out there and it's mostly too cloudy to have a clear satellite view. So how can we know what's really going on? Or can we?
And of course we can't really know, but how to decide the deductions are good enough?

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #195 on: June 19, 2014, 10:03:07 AM »
This is a REALLY stupid question. It deserves to get me expelled.
Elsewhere on the forum there is a fair bit of cognitive dissonance over the stories told by NSDIC and so on compared with weather reports. There aren't enough buoys out there and it's mostly too cloudy to have a clear satellite view. So how can we know what's really going on? Or can we?
And of course we can't really know, but how to decide the deductions are good enough?
There's a lot that can be gleaned by via satellite looking at the height of the atmosphere, and how it responds/reflects various wavelengths of EMR, from visible down.  It doesn't depend on visible light.

There's a lot which can be interpolated between buoys, so even though they are sparse, a lot can be gathered from them.

So on a broad scale, we know a lot about what is going on in the arctic.  That understanding also applies to longer time scales, as we can read the history of the weather in climate and seasonal changes.

Our understanding becomes somewhat fuzzier as we move to shorter time spans, and areas outside of those immediately in the vicinity of sensors, or which do not lend themselves to easy interrogation by sensors examining specific frequencies of light or radio waves.
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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #196 on: June 19, 2014, 10:07:00 AM »
And of course we can't really know, but how to decide the deductions are good enough?

That's not a stupid question at all, and certainly not one that should result in expulsion!

What counts as "good enough"? Surely any information is better than none? Some frequencies "see" through clouds better than others, but unfortunately none of them seem terribly good at working out the thickness of the ice, especially at this time of year.
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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #197 on: June 20, 2014, 04:09:10 PM »
What is the immediate ghg equivalency of methane? I understand using the 20 or 100 year equivalency when reporting the release of a particular mass of methane such as 50 gt. I don't understand using a 20 or 100 year equivalency when reporting parts per billion. If methane in the atmosphere is 1865 ppb its ghg effect will only decrease if its parts per billion decreases. It makes more sense to me to report the 100 year effect when discussing a mass or volume of menthane but use the immediate effect when discussing fractions of the atmosphere.

SteveMDFP

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #198 on: June 20, 2014, 07:27:50 PM »
What is the immediate ghg equivalency of methane? I understand using the 20 or 100 year equivalency when reporting the release of a particular mass of methane such as 50 gt. I don't understand using a 20 or 100 year equivalency when reporting parts per billion. If methane in the atmosphere is 1865 ppb its ghg effect will only decrease if its parts per billion decreases. It makes more sense to me to report the 100 year effect when discussing a mass or volume of menthane but use the immediate effect when discussing fractions of the atmosphere.
I concur.  I think reporting on methane effects has been flawed, and flawed in a direction that understates the importance and effect of stable (or rising) methane levels.

Laurent

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #199 on: June 21, 2014, 11:10:14 AM »
Can't find the info on official site but I have heard that methane is 100 times more powerful than CO2 once immediately release and N20 300 time...To me what does matter is that direct effect not the statistical calculation based on natural decrease over time. Of course keep in mind that N2O is a thousand time less concentrated.
If someone could send as a link to official research...thanks in advance.