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Daniel B.

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #1350 on: February 03, 2018, 03:07:47 PM »
Yesterday somebody was telling that you can predict a drought 5 years in advance, the location. Is that true ?

No.  That is false.  To date, the best forecasts are one year out, but that is only for regions with very low seasonal climate variability.  There are just too many factors that influence drought formation.

Read the following:

http://drought.unl.edu/DroughtBasics/PredictingDrought.aspx

El Cid

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #1351 on: February 03, 2018, 08:21:10 PM »
Ok, here is my stupid question.

Everybody here is raving about the coming arctic storm and the splitting of the polar vortex but i am not a meteorologist.

question 1: is it such a rare occurrance?
question 2: what causes it?
bonus question: could somene give me a brief summary of the upcoming event in layman's terms?

thanks

Iceismylife

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #1352 on: February 07, 2018, 07:32:55 PM »
Ok, here is my stupid question.

Everybody here is raving about the coming arctic storm and the splitting of the polar vortex but i am not a meteorologist.

question 1: is it such a rare occurrance?
question 2: what causes it?
bonus question: could somene give me a brief summary of the upcoming event in layman's terms?

thanks
It is my understanding that what drives a GAC is the available heat in the water vs. the cold in the ice.  This explanation is less than scientific and my apologies for that.

So if the limit is not the availability of heat in the water, then is it the presence of ice on the surface?

Will the cyclone persist until the ice is gone?  Or will it run out of heat in the water first?  What is limiting?
this thread has info that may answer your questions.

Layman

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #1353 on: February 12, 2018, 02:40:09 PM »
Hi Folks,

I'm back with another stupid question.

You may have noticed I use this thread as a kind of comfort zone when I'm 'feeling the heat' of climate change during the australian summer.

Anyway, I've been digging around for some scrap of hope that somehow we're going to get relief from the heat, and I came across this Solar Cycle business. Seems like there's some dispute about the impact this has on climate although perhaps it will provide some relief?

I know that isn't strictly speaking an Arctic Sea Ice question but I'm hardly going to go to some other section of the forum with my stupid questions am I???

gerontocrat

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #1354 on: February 12, 2018, 03:19:05 PM »
Find the new thread by typing "solar cycle" into the search function. here is a lot there. (In my view just another distraction)
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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #1355 on: February 12, 2018, 03:51:27 PM »
Relief from global warming? Not enough to save us.
Relief from climate change? It will probably make it worse. Earth systems that have been linked to the variability of the solar cycle will experience warming while the solar clock indicates cooling.
I am an energy reservoir seemingly intent on lowering entropy for self preservation.

Layman

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #1356 on: February 12, 2018, 03:54:34 PM »
Find the new thread by typing "solar cycle" into the search function. here is a lot there. (In my view just another distraction)

I agree with you, but really I need a distraction from other bits of my life, which only impending doom can fulfill!

Also your posts in this thread. They are entertaining  :)


Dharma Rupa

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #1357 on: February 12, 2018, 08:44:56 PM »
Find the new thread by typing "solar cycle" into the search function. here is a lot there. (In my view just another distraction)

I've got to agree with this.  If someone can give us a correlation between solar output and ground temperature I might pay a whole lot more attention to the Sun, but so far I've seen nothing meaningful.


Pmt111500

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #1358 on: February 13, 2018, 04:00:48 AM »
Find the new thread by typing "solar cycle" into the search function. here is a lot there. (In my view just another distraction)

I've got to agree with this.  If someone can give us a correlation between solar output and ground temperature I might pay a whole lot more attention to the Sun, but so far I've seen nothing meaningful.

Well. The surface temperature on earth does follow the sun. This is seen clearly with summer and winter. The fact that on much of earth the hottest temperatures are way later in year than the maximum local suns energy input suggests there is something other in play. This something other is the ocean which heats up way deeper than land and releases the heat gained slowly on it's poleward journey on surface (ocean's hottest on surface near equator, thus most swollen, thus surface water flows poleward) This delay is ~2 months as calculated statistically (by Foster&Rahmstorf several years ago, sorry if the spelling of the names is false). The longer 11 year cycle would possibly effect the ozone layer and this might be even seen if the ozone layer hadn't been shot near death by our planets' tech'savvy species in the 1970s and 1980s. Some (or was it the same fellows?) have calculated a small effect in temperature too but I don't remember it offhand as it was too small to have an effect except in select cases. (Hoping the icing rain out warms up a bit and I don't need to use salt on stairs, I might need to get studded straps on shoes)
« Last Edit: February 13, 2018, 06:09:18 AM by Pmt111500 »

sidd

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #1359 on: February 13, 2018, 06:08:19 AM »
" (ocean's hottest on surface near equator, thus most swollen, thus surface water flows poleward) "

not really. look up ocean gyres.

sidd

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #1360 on: February 13, 2018, 06:13:16 AM »
" (ocean's hottest on surface near equator, thus most swollen, thus surface water flows poleward) "

not really. look up ocean gyres.

sidd

Didn't want to go on to coriolis force on a sun related issue.

Layman

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #1361 on: February 13, 2018, 06:33:47 AM »
Find the new thread by typing "solar cycle" into the search function. here is a lot there. (In my view just another distraction)

I've got to agree with this.  If someone can give us a correlation between solar output and ground temperature I might pay a whole lot more attention to the Sun, but so far I've seen nothing meaningful.

Well. The surface temperature on earth does follow the sun. This is seen clearly with summer and winter. The fact that on much of earth the hottest temperatures are way later in year than the maximum local suns energy input suggests there is something other in play. This something other is the ocean which heats up way deeper than land and releases the heat gained slowly on it's poleward journey on surface (ocean's hottest on surface near equator, thus most swollen, thus surface water flows poleward) This delay is ~2 months as calculated statistically (by Foster&Rahmstorf several years ago, sorry if the spelling of the names is false). The longer 11 year cycle would possibly effect the ozone layer and this might be even seen if the ozone layer hadn't been shot near death by our planets' tech'savvy species in the 1970s and 1980s. Some (or was it the same fellows?) have calculated a small effect in temperature too but I don't remember it offhand as it was too small to have an effect except in select cases. (Hoping the icing rain out warms up a bit and I don't need to use salt on stairs, I might need to get studded straps on shoes)

I know we all love anecdotal evidence in this thread.

The UV radiation is bothering me more than the heat these days. I feel like I'm getting Cancer after about 5 minutes in the afternoon sun.


Pmt111500

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #1362 on: February 13, 2018, 07:29:00 AM »
When to expect the warmest day? Found the US map from here:
https://www.ncdc.noaa.gov/news/warmest-day-of-the-year
The further from ocean and the dryer the place, the closer to solstice the day is.
Surely there's a similar map for all the globe too, somewhere? Is that particular piece of info clearly mapped on the net some öwhere?

jai mitchell

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #1363 on: February 13, 2018, 07:30:52 AM »
What you are likely experiencing is the increased strengthening of domes of high pressure when they pass over.  This low-moisture air is responsible for much of the global deserts at the 35th degree latitude.  A result of the Hadley Cell which has been observed expanding both north and south.

You are also experiencing an increased effect from Methane which is not just a greenhouse gas but also re-reflects shortwave radiation back to earth.

http://onlinelibrary.wiley.com/doi/10.1002/2016GL071930/pdf
Quote
Methane’s RF is particularly impacted
because of the inclusion of the shortwave forcing; the 1750–2011 RF is about 25% higher (increasing from 0.48Wm−2 to 0.61Wm−2 ) compared to the value in the Intergovernmental Panel on Climate Change (IPCC) 2013 assessment; the 100year global warming potential is 14% higher than the IPCC value.
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jai mitchell

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #1364 on: February 13, 2018, 07:36:25 AM »
FYI
Haiku of Futures Passed
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are not tri-color bar graphs
+3C today

DavidR

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #1365 on: February 13, 2018, 08:34:47 AM »
NASA's view on the solar cycle is given here:

"Do Variations in the Solar Cycle Affect Our Climate System?"
https://www.giss.nasa.gov/research/briefs/rind_03/
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Ninebelowzero

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #1366 on: February 13, 2018, 11:07:24 AM »
As the Earth nestles like a pea in an electromagnetic pod some scientists are beginning to suspect Earth/Solar interactivity is much more complex.

Nasa's GOLD and ICON missions will attempt to study this.

https://www.nasa.gov/icon

https://www.nasa.gov/feature/goddard/2018/nasa-s-gold-powers-on-for-the-first-time


Peter Ellis

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #1367 on: February 13, 2018, 11:12:52 AM »
" (ocean's hottest on surface near equator, thus most swollen, thus surface water flows poleward) "

not really. look up ocean gyres.

sidd

Didn't want to go on to coriolis force on a sun related issue.

Ocean currents are way more complex than this, and not particularly driven by equatorial solar heating of the surface layers.
https://en.wikipedia.org/wiki/Thermohaline_circulation

Pmt111500

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #1368 on: February 13, 2018, 12:00:30 PM »
" (ocean's hottest on surface near equator, thus most swollen, thus surface water flows poleward) "

not really. look up ocean gyres.

sidd

Didn't want to go on to coriolis force on a sun related issue.

Ocean currents are way more complex than this, and not particularly driven by equatorial solar heating of the surface layers.
https://en.wikipedia.org/wiki/Thermohaline_circulation

There's of course also the Moon which creates tides and drives coastal currents. Tides are notoriously difficult to calculate, but they do give small pulses to larger currents. At least where there are continents blocking water from flowing laminarly along smooth ocean bottoms. No doubt there are plenty other things influencing the local influx of warm waters. https://en.m.wikipedia.org/wiki/Orbit_of_the_Moon
« Last Edit: February 13, 2018, 12:09:05 PM by Pmt111500 »

mitch

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #1369 on: February 13, 2018, 05:12:49 PM »
Yes, ocean circulation is complicated. Here is a great animation made by the ECCO (Estimating the Circulation and Climate of the Ocean) consortium with NASA: https://www.nasa.gov/topics/earth/features/perpetual-ocean.html

Tor Bejnar

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #1370 on: February 15, 2018, 04:33:55 PM »
Why is the Baltic Sea not an included region whereas the St. Lawrence Gulf and Sea of Okhotsk are included.

Is it because
Quote
The salinity of the Baltic Sea water is only approximately 20% of the salinity of the oceans (35 per mille). Furthermore, the salinity of the Baltic Sea's surface water reduces towards the North, and the water in the Bay of Bothnia and at the bottom of the Gulf of Finland is almost fresh.
[About the Baltic]
or (ref.) 1-8‰ at the surface and 15-20‰ at depth.


The St. Lawrence Gulf has salinity of something like 28-34‰
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Pmt111500

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #1371 on: February 15, 2018, 08:14:57 PM »
Why is the Baltic Sea not an included region whereas the St. Lawrence Gulf and Sea of Okhotsk are included.

Is it because
Quote
The salinity of the Baltic Sea water is only approximately 20% of the salinity of the oceans (35 per mille). Furthermore, the salinity of the Baltic Sea's surface water reduces towards the North, and the water in the Bay of Bothnia and at the bottom of the Gulf of Finland is almost fresh.
[About the Baltic]
or (ref.) 1-8‰ at the surface and 15-20‰ at depth.


The St. Lawrence Gulf has salinity of something like 28-34‰

Aww, yes the salinity is way lower here thus freezes way easier than Arctic. In fact some people in the shores of bay of Bothnia use Baltic water as such to cook vegetables/potatos.

Sebastian Jones

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #1372 on: February 15, 2018, 08:15:20 PM »
Why is the Baltic Sea not an included region whereas the St. Lawrence Gulf and Sea of Okhotsk are included.

I don't know why not, but for more information on Baltic ice see this thread:https://forum.arctic-sea-ice.net/index.php?topic=1865.0

sark

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #1373 on: February 24, 2018, 07:05:03 AM »
How is GEFS at predicting 250mb winds at +15 days?

https://imgur.com/uXDTQbs

vigilius

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #1374 on: February 24, 2018, 04:32:06 PM »
I have been following the discussion on the freezing season thread and was struck by the open water showing up north of Greenland, so I went to NASA Worldview to see what it looked like there. But there is now a huge hole in the polar coverage, no way to see the north of Greenland, Fram Strait, etc. Is this something that happens this time of year? Is it OTOH something to do with the lost satellite coverage I read about last year? Is it going to get better? Thanks.

El Cid

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #1375 on: February 24, 2018, 04:43:10 PM »
How is GEFS at predicting 250mb winds at +15 days?

https://imgur.com/uXDTQbs

It's easy, they run their model and show the results. They could show the results from the model for 30 or even 60 days, but it would not make sense, since we know that after 5-6 days (see chaos theory) the predictions are becoming less and less reliable. Anything beyond 10 days is vudu to me.

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #1376 on: February 24, 2018, 07:57:56 PM »
I have been following the discussion on the freezing season thread and was struck by the open water showing up north of Greenland, so I went to NASA Worldview to see what it looked like there. But there is now a huge hole in the polar coverage, no way to see the north of Greenland, Fram Strait, etc. Is this something that happens this time of year? Is it OTOH something to do with the lost satellite coverage I read about last year? Is it going to get better? Thanks.
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gerontocrat

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #1377 on: February 24, 2018, 08:44:09 PM »
Or be lazy and get their pretty graphic at
https://nsidc.org/data/seaice_index/images/daily_images/N_daily_concentration_hires.png

Shows the low concentration north of Greenland near as dammit all the way to the pole, and the low concentration reaching into the CAB at the Pacific end.
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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #1378 on: February 25, 2018, 07:19:07 AM »
How is GEFS at predicting 250mb winds at +15 days?

https://imgur.com/uXDTQbs

Not that good, and under most conditions you should expect it to regress towards an even, weak zonal flow as you go further out.

GEFS is an ensemble unlike GFS. It's a blend of the GFS operational run plus a bunch of other ensembles that have initial conditions slightly varied to seed other runs.

Because of that, you should expect values to smooth out in the long term. Anything that still shows up further in the future indicates a more persistently expected long-term trend.
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Hyperion

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #1379 on: February 25, 2018, 09:22:52 AM »
When neven says "i'm going to be moderating your posts for a while" how long does he usually mean. Is 10 months unusual?
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Neven

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #1380 on: February 25, 2018, 11:09:49 AM »
I forgot why I put you on moderation, Hyperion, but I see now it was because of 'ranting, derailing and pontificating', and I vaguely remember you posting lots of images. I'll put you off moderation, but try to be on-topic and as efficient as you can. Remember, this is all extra work for me.
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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #1381 on: February 25, 2018, 11:24:25 AM »
Why is the Baltic Sea not an included region whereas the St. Lawrence Gulf and Sea of Okhotsk are included.

Is it because
Quote
The salinity of the Baltic Sea water is only approximately 20% of the salinity of the oceans (35 per mille). Furthermore, the salinity of the Baltic Sea's surface water reduces towards the North, and the water in the Bay of Bothnia and at the bottom of the Gulf of Finland is almost fresh.
[About the Baltic]
or (ref.) 1-8‰ at the surface and 15-20‰ at depth.


The St. Lawrence Gulf has salinity of something like 28-34‰

I am not sure what exactly you mean by Baltic is not included, but it is included in NSIDC sea ice extent and ADS/NIPR sea ice extent. My UH AMSR2 sea ice area/extent data and graphs did not include the Baltic region, but probably will do so starting this melting season.

It is a small region bounded by land. NSIDC SSMS based data is severely affected by the land spillover effect and therefore inaccurate. Data based on the Jaxa AMSR(E|2) measurements are more accurate, see attached Uni Hamburg 3.125km graphs.



Hyperion

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #1382 on: February 25, 2018, 12:11:47 PM »
I forgot why I put you on moderation, Hyperion, but I see now it was because of 'ranting, derailing and pontificating', and I vaguely remember you posting lots of images. I'll put you off moderation, but try to be on-topic and as efficient as you can. Remember, this is all extra work for me.

Thank you for that. And for clarifying the reasons. Heres me thinkinking all this time that it was for my ill judged attempt to lighten a rather tense and combative atmosphere that was apparent here with an ill judged joke, and then some character acting in the wording of a reply to Jim Hunt. Fortunately I got lots of supportive and helpful advice filled PMs from regulars here, so have tempered my approach and am glad you judge me tolerable.

Policy: The diversion of NZ aluminum production to build giant space-mirrors to melt the icecaps and destroy the foolish greed-worshiping cities of man. Thereby returning man to the sea, which he should never have left in the first place.
https://en.wikipedia.org/wiki/McGillicuddy_Serious_Party

gerontocrat

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #1383 on: February 25, 2018, 01:02:29 PM »
I forgot why I put you on moderation, Hyperion, but I see now it was because of 'ranting, derailing and pontificating', and I vaguely remember you posting lots of images. I'll put you off moderation, but try to be on-topic and as efficient as you can. Remember, this is all extra work for me.

Thank you for that. And for clarifying the reasons. Heres me thinkinking all this time that it was for my ill judged attempt to lighten a rather tense and combative atmosphere that was apparent here with an ill judged joke, and then some character acting in the wording of a reply to Jim Hunt. Fortunately I got lots of supportive and helpful advice filled PMs from regulars here, so have tempered my approach and am glad you judge me tolerable.
I think I was still a lurker when Neven (correctly) first took me to task.
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Pmt111500

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #1384 on: February 25, 2018, 02:22:01 PM »
Add to the Baltic inclusion, yes it is watched. The extent of Baltic freeze is more connected to cold intrusions from Siberia rather than Arctic/Greenland, so it's not very indicative of Arctic state. But as Wipneus said it's watched and if necessary can be included. It melts anyway in summers so it doesn't matter in counting multiyear ice (2-year included).

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #1385 on: February 25, 2018, 03:53:17 PM »
Does anyone know how the DMI integrates temperatures across the entire 80 N circle into a single temperature?  I don't know exactly what this is saying:

Calculation of the Arctic Mean Temperature
The daily mean temperature of the Arctic area north of the 80th northern parallel is estimated from the average of the 00z and 12z analysis for all model grid points inside that area. The ERA40 reanalysis data set from ECMWF, has been applied to calculate daily mean temperatures for the period from 1958 to 2002. From 2002 to present the operational model (at all times) from The ECMWF is used for mean temperature calculations.

How is the temperature for the grid points actually acquired?



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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #1386 on: February 25, 2018, 04:33:45 PM »
DMI's 2m temps are meant to be compared to other years and since there's only a handful of land stations above 80°N, data from ground, aircraft, bouys, ship, satellites, radiosondes, etc. are all combined.
The explanation is found in the pdf at the bottom of DMI's page:
http://ocean.dmi.dk/arctic/documentation/arctic_mean_temp_data_explanation_newest.pdf
Quote
However, since the model is gridded in a regular 0.5 degree grid, the mean temperature values are strongly biased towards the temperature in the most northern part of the Arctic! Therefore, do NOT use this measure as an actual physical mean temperature of the arctic. The 'plus 80 North mean temperature' graphs can be used for comparing one year to an other.
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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #1387 on: February 25, 2018, 08:39:51 PM »
Thanks Wipneus, re Baltic response.  The question is based on the "Arctic Regions" identified on the ASIG Regional graphs tab 'ignoring' the Baltic Sea.  (That map is basically from the Cryosphere Today website.)

A picture's worth a thousand words (just a thousand :P). No pictures shows 'all truths', but it's easy to forget!

As the Baltic is included in Arctic area and extent numbers, could the CT map be further modified to ID the Baltic?  Are there other areas similarly 'overlooked'?

Edit: There is more to it, though, Baltic ice is sometimes not counted because it is in a 'minor' area.  But maybe not counted in August because there isn't any ice there then, and any satellite counted pixels are just spurious?
« Last Edit: February 26, 2018, 06:12:57 AM by Tor Bejnar »
Arctic ice is healthy for children and other living things because "we cannot negotiate with the melting point of ice"

Pmt111500

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #1388 on: February 26, 2018, 05:10:55 AM »
Those interested in current state of ice on Baltic may employ the map FMI and SMHI produce, http://cdn.fmi.fi/marine-observations/products/ice-charts/latest-full-color-ice-chart.pdf . The more saline and wider deeper regions are still devoid of ice. Also, see http://ilmatieteenlaitos.fi/jaatilanne (comparison to 'normal', which here is 1965-1986. I guess, this is because prior 1965 there wasn't enough homogeneous data outside shipping lanes and 1987 was an exceptionally cold winter with almost full ice coverage). I couldn't quickly find historical values now, but they are stored somewhere either in Sweden or in Finland. It's pretty clear though, the ice amounts have been diminishing here as well.
« Last Edit: February 26, 2018, 07:33:32 AM by Pmt111500 »

Pmt111500

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #1389 on: February 26, 2018, 05:37:59 AM »
And of course the historical data set of maximum ice on Baltic can nowadays be found at European Union-site; https://www.eea.europa.eu/data-and-maps/indicators/arctic-sea-ice-2/assessment
including a screencapture, looks like the Littel Ice Age begun here in the 1750s, which doesn't fit to Maunders' minimum nor to the large eruption of Laki in 1783. Maybe there's an Atlantic current that cooled down or weakened back then and directed warm air elsewhere.

Full ice cover easily deduced from the graph to be ~420Kkm2. This likely includes the straits and narrow oceany Kattegat (https://en.wikipedia.org/wiki/Kattegat) between Denmark and Sweden.
« Last Edit: February 26, 2018, 07:56:24 AM by Pmt111500 »

Wipneus

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #1390 on: February 26, 2018, 10:04:42 AM »
Thanks Wipneus, re Baltic response.  The question is based on the "Arctic Regions" identified on the ASIG Regional graphs tab 'ignoring' the Baltic Sea.  (That map is basically from the Cryosphere Today website.)

A picture's worth a thousand words (just a thousand :P). No pictures shows 'all truths', but it's easy to forget!

As the Baltic is included in Arctic area and extent numbers, could the CT map be further modified to ID the Baltic?  Are there other areas similarly 'overlooked'?


As it happens I was wondering about those (or very similar) questions some time ago. Taking the Cryosphere Today regions, looking at the Multisensor Analyzed Sea Ice Extent (MASIE) defined regions and wanting to include all sea regions I came up with my extended region map (attached).

On the pacific side there are three more regions defined:
- Gulf of Alaska
- Open Pacific Ocean
- Japanese/Yellow Seas

On the Atlantic side we have:
- Gulf of Maine
- Open Atlantic Ocean
- Baltic Sea

"Lakes" serves as a kind of pseudo-region.

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #1391 on: February 26, 2018, 11:35:17 AM »
Those interested in current state of ice on Baltic may employ the map FMI and SMHI produce, http://cdn.fmi.fi/marine-observations/products/ice-charts/latest-full-color-ice-chart.pdf . The more saline and wider deeper regions are still devoid of ice. Also, see http://ilmatieteenlaitos.fi/jaatilanne (comparison to 'normal', which here is 1965-1986. I guess, this is because prior 1965 there wasn't enough homogeneous data outside shipping lanes and 1987 was an exceptionally cold winter with almost full ice coverage). I couldn't quickly find historical values now, but they are stored somewhere either in Sweden or in Finland. It's pretty clear though, the ice amounts have been diminishing here as well.
SMHI has some previous reports avialable on this page:
https://www.smhi.se/klimatdata/oceanografi/havsis
The summaries under "Sammanfattning av issäsonger" is also written in English.

Maxiumum values since 1957 in this spreadsheet:
https://www.smhi.se/polopoly_fs/1.20053!/havsis.xlsx
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sark

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #1392 on: February 27, 2018, 12:19:50 AM »
In this 2016 video animation of Arctic Sea Ice age put out by NASA, why isn't the CAA included in sea ice extent?


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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #1393 on: February 27, 2018, 01:58:40 PM »
My guess is that it's more difficult to track sea ice age because of the many channels in the CAA.
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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #1394 on: April 03, 2018, 08:03:12 AM »
Hi, noob question. Arctic sea ice volume increases until mid-April, while the sea ice extent typically peaks a month or so earlier. Melting from the edges is a very obvious cause of extent decrease, but what are the mechanisms that allow growth in volume for a month after the melting begins? Is it addition by freezing to the bottom surface, tectonic squeezing, snow, and what is the most important of these? Thanks for any pointers.
First, your assumption is correct, melting from the (quite southerly) peripheral edges causes early extent decrease. Second, growth in volume reasons are mostly bottom freezing due to low temps in the arctic basin proper, but also refreezing of resultant cracks and leads after the ice is "compressed" (not proper term, but when ridges are formed).
Snow is not counted in ice volume, so is not directly relevant. In fact snow on the ice slows bottom freezing due to its insulation properties. (Later it slows melt thanks to reflection of sunlight.)
« Last Edit: April 03, 2018, 06:44:40 PM by oren »

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #1395 on: April 03, 2018, 03:15:04 PM »
Thanks for the quick reply!

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #1396 on: April 04, 2018, 08:35:35 PM »
From the 2018 melting season thread:

Hi new person here. Couple of quick questions.

1. When do scientists estimate the arctic will get it's first blue ocean event?

2. Any chance it will be ice free later this year? If yes around what time?

2. When the arctic is free of sea ice for the the first time what kind of global effects will it have on the weather?
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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #1397 on: April 04, 2018, 08:43:25 PM »
From the 2018 melting season thread:

Hi new person here. Couple of quick questions.

1. When do scientists estimate the arctic will get it's first blue ocean event?

2. Any chance it will be ice free later this year? If yes around what time?

2. When the arctic is free of sea ice for the the first time what kind of global effects will it have on the weather?

1. Most scientists estimate it will happen anywhere between 2020 and 2050. https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1002/grl.50316

2. I would say it is possible, but unlikely.

3. When the arctic has its first blue ocean event, the outcome will have dire consequences.
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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #1398 on: April 04, 2018, 08:56:58 PM »
Hi avaliablewrongdoer, and welcome. There are whole discussions on the forum about the content of your questions. Be warned that there are many opinions about this very subject, and arguments are quite heated. Try reading through the following link, for example. You might get lost but you also might gain some knowledge.
https://forum.arctic-sea-ice.net/index.php/topic,2286.msg147717.html#msg147717

Thomas Barlow

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #1399 on: April 05, 2018, 02:12:15 AM »
From the 2018 melting season thread:

Hi new person here. Couple of quick questions.

1. When do scientists estimate the arctic will get it's first blue ocean event?

2. Any chance it will be ice free later this year? If yes around what time?

3. When the arctic is free of sea ice for the the first time what kind of global effects will it have on the weather?

Well, I was going to say "no chance", to the 2nd one, but then I saw this: https://climatenewsnetwork.net/arctic-ice-depends-on-half-a-degree-of-heat/
And combine that with this: http://cci-reanalyzer.org/wx/DailySummary/#t2anom

But, to be realistic, yea, there is no chance of that happening in the next 10 years IMO. Maybe 20. Probably never.
« Last Edit: April 05, 2018, 02:08:52 PM by Thomas Barlow »