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Messages - oren

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1
Greenland and Arctic Circle / Re: The Nares Strait thread
« on: March 29, 2017, 05:41:17 PM »
I am wondering if a strong wind from the south can somehow break the Lincoln "arch". For now it looks to be frozen solid, but as the whole area of thick ice north of Greenland is currently cracking badly and flowing towards the Fram, except for the Lincoln Sea area directly adjacent to Nares, it means that there is a risk that cannot be discounted. And I assume the main strength of the arch is against stresses towards Nares, less so for stresses in the opposite direction.

2
Arctic sea ice / Re: The 2017 melting season
« on: March 29, 2017, 05:33:24 PM »
Latest GFS anomalies until next Wednesday (Climate Reanalyzer). Added 5-day forecast, which is still red all the way from Kara Sea to Beaufort.
romett1, thanks for posting the GFS anomalies+forecast. It seems that every time I look at the table the forecast a few days out shows the anomaly lessening. But every time you post an update the anomaly stays high. Is it just my imagination? Or is the GFS underestimating the forecast anomaly?

3
Arctic sea ice / Re: The 2017 melting season
« on: March 28, 2017, 05:32:00 PM »
johnm33's wonderful animation tells it all, the Beaufort is thickening and seems to be compacting as well, plus there is almost no gyre, I am guessing this is why it's not fracturing, while all the old ice in the CAB is tearing apart and spilling down the Fram.
I wonder if the Beaufort will manage to start late this year - I doubt it but it's becoming a possibility. Might balance the Beaufort's lack of MYI and high vulnerability to early meltout.

4
Antarctica / Re: Sea Ice Extent around Antarctica
« on: March 28, 2017, 05:01:16 PM »
The main difference from previoues years is the Ross Sea. Other seas are within the historic variance, though on the low side. Not sure what happened there, I used to think it was some Pacific teleconnection from the monster El-Nino, not sure anymore. If next year repeats the same performance in Ross, it will be even more interesting.

5
Arctic sea ice / Re: Stupid Questions :o
« on: March 28, 2017, 05:55:10 AM »
This reminds me of another question I have, will CST plants become more efficient in a hotter climate?

I guess it depends on the weather...
I don't think efficiency will improve. My intuition tells me the output is dependent on the difference between the solar heat achieved and the ambient temperature used to cool back the steam. Solar irradiation remains the same while temps rise, a recipe for less efficiency not more.

6
We are now down to philosophy. In practical terms, the question is whether the circulation changes are "random" in that there is no underlying trend in them, even if influenced by human activities. In such a case, sea ice should rebound when the random dice roll the other way. OTOH, if the circulation changes have an underlying noisy trend due to human activities, then sea ice ain't coming back.
(My own worthless opinion is in the second camp)

7
Arctic sea ice / Re: The 2017 melting season
« on: March 27, 2017, 08:25:23 PM »
Hyperion this is good stuff but should be in some other thread, not sure which though. But this stuff ain't arctic melting season.

8
Arctic sea ice / Re: Stupid Questions :o
« on: March 27, 2017, 05:27:26 PM »
Layman, seeing an ice-free arctic within 10 years is high probability event (IMHO).
Cataclysmic release of methane - improbable (IMHO). Yes the arctic ocean will warm in the summer, and yes this will have a big effect, but not the immediate end of the world.
Over time, the feedback effects from methane clathrate release, permafrost methane and CO2 release, and loss of albedo with the loss of summer sea ice, will all bring about increased warming beyond that guaranteed by human emissions. But I can't see this as one big bang in some very near timeframe.

9
Permafrost / Re: Negative Feedback of Positive Snowfall Anomalies
« on: March 27, 2017, 12:16:57 AM »
Well said wili.

10
Consequences / Re: Global Surface Air Temperatures
« on: March 26, 2017, 08:19:17 AM »
Since we are already OT: What's up with that Miriam?  ::)

Showing results for Merriam Webster
Search instead for Miriam Webster

11
Arctic sea ice / Re: Albedo-Warming Potential
« on: March 25, 2017, 10:58:26 AM »
It tells me that permission is required to view the graphs updated for 2017.

Ah sorry I forgot to make the images public. It should be fixed now.
For some reason I still find many of the images on the site appear as broken icons and are not loading. Not sure why.

12
Arctic sea ice / Re: Albedo-Warming Potential
« on: March 25, 2017, 08:33:56 AM »
Thanks Tealight. I expect your graphs will be very busy this year.

13
Greenland and Arctic Circle / Re: The Nares Strait thread
« on: March 24, 2017, 10:19:56 PM »
Yes, there is an almost-constant current flowing from the Lincoln sea to Baffin bay, I seem to remember it's being driven by surface height differences, but people on this forum could shed more light on this. I also found this image on the net which might help a bit.

14
Permafrost / Re: Negative Feedback of Positive Snowfall Anomalies
« on: March 23, 2017, 05:38:50 PM »
If wintertime extent is fairly normal, then there is currently no albedo anomaly, just extra snow that seems to melt very quickly when spring arrives, therefore gaining no annual anomaly. And since the ocean's albedo anomaly could bring extra summer heat, the nearby conintents could become even warmer than they currently are in summer.
Regarding snow surviving in Siberia or Canada, I seem to remember nearly 30oC in Siberia at some point last summer or the one before, maybe the same in Alaska too. Can't build an ice sheet under such conditions. I personally fail to see the possible changes in weather or circulation that could save the continental snow for next year. Or even for enough time to give a significant anomaly.

Is there any chart of snow extent anomaly through the year for the last couple of years? Could help quantify my gut feeling.

15
Permafrost / Re: Negative Feedback of Positive Snowfall Anomalies
« on: March 23, 2017, 12:19:22 PM »
A couple of comments:
Are we talking about more snow thickness, or more snow extent? only the latter has any albedo effect.

I seem to recall that we have positive snow anomalies in winter, and negative in spring. I would not be surprised if the annual net change in albedo times insolation is actually negative. This needs quantification, as it is the whole basis of bbr's hypothesis.

As the Younger Dryas has been mentioned - it has a very good explanation unrelated to albedo. When the Laurentide ice sheet retreated, large accumulations of icy meltwater were trapped on land, and periodically discharged into the ocean causing a temporary drop in global temps.
From Wikipedia: The prevailing theory is that the Younger Dryas was caused by significant reduction or shutdown of the North Atlantic "Conveyor", which circulates warm tropical waters northward, in response to a sudden influx of fresh water from Lake Agassiz and deglaciation in North America. Geological evidence for such an event is thus far lacking.[47] The global climate would then have become locked into the new state until freezing removed the fresh water "lid" from the north Atlantic Ocean. An alternative theory suggests instead that the jet stream shifted northward in response to the changing topographic forcing of the melting North American ice sheet, bringing more rain to the North Atlantic which freshened the ocean surface enough to slow the thermohaline circulation.[48]

16
Greenland and Arctic Circle / Re: Wandel Sea / North East Greenland
« on: March 22, 2017, 10:30:41 PM »
As if all these old floes can't wait. They are simply rushing to get out the Fram

17
Greenland and Arctic Circle / Re: Greenland ice sheet retreat
« on: March 22, 2017, 10:29:07 PM »
Ice sheets are massive, land-based and are found in Greenland and Antarctica.
Not really sure what the sea ice cover is called, but "ice sheet" is the wrong term and detracts from what you're trying to say.

18
Arctic sea ice / Re: IJIS
« on: March 22, 2017, 05:00:21 PM »
Ah. Methodology flaw alert - thanks Oren. The COUNTIF was looking for days ranked 28th, 27th and 26th. And for dates we haven't had this year yet, they actually only go from 1 to 27.

I've redone it so it counts if a day is ranked 25th, 26th and 27th i.e. the previous 'bottom 3'. That means that 2006, 2007, 2011 and 2015 gain some bottom 3 days - so yes, by the end of their years they have more bottom 3s than 2017 at the moment. But not by much. As things stand,  2017 could well overtake those year by the end of April.

This needs some more work! Good to have friendly peer-reviewers.

I don't have an online graph repository - any suggestions? Google Drive?
OT developer tips:
A. Maybe sort in reverse, and pick 1st, 2nd, 3rd.
B. Or, use small(1), small(2), small(3) if you're calculating in Excel.
About posting online I am clueless.

19
Arctic sea ice / Re: IJIS
« on: March 22, 2017, 02:31:55 PM »
Deeenngee, in your graph - does it calculate the top 3 at the current time? Meaning that assuming 2017 takes 1st place tomorrow, some year will reduce its daycount by one in the graph?
In addition, do you have these great graphs updated online somewhere?

20
Arctic sea ice / Re: The 2017 melting season
« on: March 21, 2017, 05:33:22 PM »
The elephant is all mashed up, and it seems a significant part of the PIOMAS "blob" will cross the point of no return this coming week. On the other hand, eyeballing Hycom it seems the Beaufort will be thickening/compacting, and that peripheral extent might benefit from dispersion.

21
Greenland and Arctic Circle / Re: The Nares Strait thread
« on: March 21, 2017, 01:26:58 PM »
...it looks to me like Nares ice is on the move. If so---well, it's a bit early, isn't it?

In the last couple of years the Strait opened up in early July.
However, the importance of Nares lies in its export of the thickest arctic sea ice that piles up in the Lincoln Sea. As long as one of the arches holds, the ice moving through the strait is mostly thin ice that will melt anyway later. And at this time of year there might even be refreezing of the resulting open water, depending on the weather. As of now, the northern arch still holds firmly. However, having just one arch increases the risk of an early totally-open strait, especially as the northern arch is less stable than the Kane basin arch due to its large width.

btw the easiest Nares resource is http://ocean.dmi.dk/arctic/kane.uk.php and/or http://ocean.dmi.dk/arctic/lincoln.uk.php. Filtering by Sentinel images gives daily hi-res images (which are very easy to animate as they are co-located).

22
Arctic sea ice / Re: The 2016/2017 freezing season
« on: March 20, 2017, 11:32:35 PM »
It was surely discussed on the IJIS thread following the first century drop after the max.

23
Arctic sea ice / Re: The 2017 melting season
« on: March 20, 2017, 06:08:14 PM »
dosibl, the most telling areas will be the Beaufort as already been said, compared to the last few years to see wether it's early or late, and the Barents/Svalbard/Atlantic front on a qualitative basis. And not on a daily basis, PIOMAS.

24
AndrewB, welcome and thank you for putting it so concisely. To me argument 1 is still the most important, and I find the scientific claim highly questionable. The negative arctic sea ice trend is so obvious that attributing it to variable natural causes unrelated to AGW and GHGs using a model, probably means the model is not good enough.

25
Bear in mind denialists, like good populist politicians, will always find something to latch onto. After all many of them are paid to do it, and the others are fervent believers in their "cause". I doubt wording it differently would make any actual difference in the world.

26
Arctic sea ice / Re: IJIS
« on: March 18, 2017, 01:59:17 PM »
Thank you Deeenngee.
Interestingly, the two biggest drops in the past two days happened in St. Lawrence and Okhotsk, unrelated to the Atlantic-originated storms, although Barents and Kara contributed their share too.

27
Consequences / Re: Population: Public Enemy No. 1
« on: March 17, 2017, 11:14:40 PM »
Don't forget the other side, high birth rates tend to lead to poverty.
And in general, the way I look at it, of course high consumption and high population both contribute to the problem. But high consumption can be changed much quicker than demographics. Half of Niger's population is less than 15 years old. It will take 60-70 years to change the trend and lower population. In the US, theoretically the crazy consumption/ecological footprint can be lowered in 10-20 years.

28
Science / Re: 2017 Mauna Loa CO2
« on: March 17, 2017, 10:50:29 PM »
2016 data, but still....

"China CO2 emissions from fossil fuels down 1%, US down 3%  & EU flat says @IEA - global emissions flat for 3rd yr in a row"
https://twitter.com/jschmidtnrdc/status/842779914298449920

"This matters. But this is like smoker holding steady at 3 packs a day—emissions are still accumulating in the atmosphere at record rates."
https://twitter.com/ericholthaus/status/842781585334190081

Carbon Dioxide Is Rising at Record Rates
http://www.climatecentral.org/news/carbon-dioxide-record-rates-21242


So, CO2 rising at record rates while major economies are reducing rates. Attributable to feedbacks?

Feedbacks most likely, but it could also be nations lying about their statistics.

29
Antarctica / Re: Sea Ice Extent around Antarctica
« on: March 17, 2017, 10:48:55 PM »
...we have to wait and see what happens in the coming years given the very large yearly variability.
And given Hansen's feedback of melting glaciers resulting in increased sea ice around Antarctica. Should the WAIS mass loss continue to accelerate, there will be a large input of fresh cold water into the southern ocean. Very different from the Arctic, continent in the middle vs. ocean in the middle.

30
Consequences / Re: Climate change, the ocean, agriculture, and FOOD
« on: March 17, 2017, 01:23:40 PM »
I might get some flack but I think that genetic modification or advanced hybridization might be the only avenue for maintaining crop yields and avoid widespread famine...
The best avenue to avoid widespread famine is to have fewer babies.
(Not disputing your comment though)

31
Expert reaction to research on natural climate variability and Arctic summer sea ice

This resonates well with my thinking. Most other responses accept that the variability is natural without question.
Prof. Jeffrey Kargel, Glaciologist at the University of Arizona, said:

“This new work by Qinghua Ding and others – involving an analysis of the observational record of sea ice and numerical model testing to root out the causes of long-term decline and yearly variations in Arctic sea ice – does well to explain links between long-term weather in the Arctic and year-to-year variations in sea ice on the same time frame.  In other words, weather and sea ice melting and sea ice extent are connected, and Arctic weather is connected to weather elsewhere in the world, even as far away as the tropical Pacific Ocean.

“The already well-established, if imperfectly known, many-decades-long climatic connections to human root causes of the decline in sea ice are not this paper’s focus. Even so, these authors’ and others’ work shows that burning of fossil fuels is having a large direct impact in contributing to rapid sea ice declines. This paper does well to explore the effects on Arctic sea ice of year-to-year variations in Arctic and global long-term weather.  The paper does less well to explore how the ‘weather’ part of the variations are also connected indirectly– partially– to rising greenhouse gas abundances.

...

32
Arctic sea ice / Re: IJIS
« on: March 17, 2017, 06:31:20 AM »
This is probably a result of the retreat in the Kara and Svalbard/FJL due to the storm.
In any case, I doubt mother nature can recover from this back to the max, as the date is getting rather late.

33
Arctic sea ice / Re: Poll: 2017 PIOMAS Maximum Monthly Figure
« on: March 17, 2017, 06:10:05 AM »
Seaicesailor, thanks for re-posting that wonderful buoy temp animation. Very instructive.

34
Does not the lack of a calving face indicate that the terminal section of the glacier has thinned (presumably via bottom melt) to the point where it is now at or close to sea level?
I highly doubt that bottom melt (really frontal melt as the ice rests on the ground underwater) can eat through hundreds of meters of ice thickness like that, but possibly the front is partially collapsed?

35
Arctic sea ice / Re: The Slow Transition
« on: March 16, 2017, 05:32:43 PM »
Enough, please...

36
Arctic sea ice / Re: The 2017 melting season
« on: March 16, 2017, 07:24:25 AM »
The Kara retreat has started to materialize. And that red stain (the PIOMAS blob) is still inching its way towards the Fram and oblivion.

37
Consequences / Re: Population: Public Enemy No. 1
« on: March 16, 2017, 12:21:08 AM »
From deep Africa, where population growth is exponential, given that women marry at very young age and give birth to very many children:
"Having lots of children is the norm because they bring wealth (“they come with two hands to work but only one mouth to feed”). So why have four when you could have seven?"

According to the article, women don't want to use contraceptives, even when they are readily available, because they like to have many children.

The article illustrates why population growth is sure to continue for many decades to come.

https://www.theguardian.com/global-development-professionals-network/2017/mar/15/why-have-four-children-when-you-could-have-seven-contraception-niger
This article is so depressing. Such a poor country with such a high birth rate and such a culture. Totally hopeless.The only questions remaining are when will Niger collapse, and in what manner (Widespread famine? Civil war? Attacking neighbouring countries? A fundamentalist revolution? All of the above?)

38
Arctic sea ice / Re: Stupid Questions :o
« on: March 14, 2017, 04:59:32 PM »
Darvince, the question was not about the halocline, what I think i'm seeing is an increased flow of Atlantic waters penetrating past FJL/NZ into Laptev before it's energy is spent. Plus it appears to accelerate around the new/full moon peak tide min/max. Assuming that continues and as above the ice is practically liquid, and thus the easiest fraction to flush, how fast could the ice be lost? well i did a boe oom calc. and was surprised by the result. Actually shocked, so wondered if anyone else had any idea.

The Atlantic water is thought to flow around the whole of the Arctic Nansen Basin beneath the polar mixed layer, circulating counter clockwise. A-Team showed that the edge of the ice through most of the summer corresponded with bathymetry. Warmer Atlantic water flows down the continental slope to form a layer starting at around 300m depth, Where the Atlantic water is at the surface, on the continental shelf, ice melts. Within the deeper basin the Atlantic water no longer affects the ice as it is too deep, unless the denser warm water remains on the surface; that requires a break down of the Halocline. The Halocline is refreshed by freshwater input from rivers and from melting ice.
If I recall correctly, the deep Atlantic water affect basal melting of Zachariae/79N and Petermann glaciers (and maybe some others) as it flows out of the Arctic basin through Fram and Nares straits.

39
Science / Re: NOAA ESRL Global CO2 Increase Accelerating
« on: March 13, 2017, 05:26:39 AM »
There is an association between El Nino occurrences and increases in yr/yr monthly CO2 emissions rates. The most recent El Nino demonstrates that relationship.

What's more troubling is when one observes a CO2 spike with no associated El Nino. The chart illustrates the relationship between ENSO 3.4 (El Nino La Nina and monthly NOAA/ESRL CO2 increases. There is more at:

http://www.megiddo666.apocalypse4real-globalmethanetracking.com/

Eyeballing this char seems to indicate based on past correlation of spikes that our current spike might not be over nor at its peak. I hope tbat's not the case.

40
Arctic sea ice / Re: Piomas vs. CryoSat
« on: March 10, 2017, 06:01:07 PM »
The main difference, and the outstanding feature in PIOMAS this year, is the thick blob above Greenland. It's missing in both Cryosat and Hycom, at least in the magnitude alluded to by PIOMAS. I keep wondering about it, especially as it seems to be headed eventually towards the Fram which might cause a sharp drop in PIOMAS volume (if and when that happens).

41
Arctic sea ice / Re: IJIS
« on: March 10, 2017, 06:31:26 AM »
Deeenngee can you update your zoomed-in graph? I wonder where we stand

42
Arctic sea ice / Re: The 2017 melting season
« on: March 09, 2017, 11:03:49 PM »
It doesn't matter for extent if the Arctic is +20 Centigrade above average, it is still below freezing. I'll state the obvious: if the areas where ice can form are cold extent will increase despite the anomalously warm temperatures. It's why SIE is a dangerous metric to point to for sea ice loss.
Obvious but still worth repeating, especially if dispersing winds support the cold temps.
And as we are discussing the Arctic becoming seasonally ice-free, max winter extent remains almost the same while min summer extent drops sharply. So in summer SIE is a good measure. In winter probably the best measure is PIOMAS volume.

43
Consequences / Re: General Drought Stuff
« on: March 09, 2017, 05:46:07 PM »
Amazing. So now the local population near Lake Baikal, the largest reservoir of unfrozen freshwater on the planet, need to start saving water due to environmental damage. Mad world.

44
Arctic sea ice / Re: Latest PIOMAS update (March)
« on: March 09, 2017, 05:32:36 PM »
HELP ! Which are the easiest places to get graphs on volume during the month ? (I am a sea ice volume addict and the PIOMAS monthly update fix wears off  too soon).
Besides the PIOMAS daily data which annoyingly gets updated once a month, there is the DMI volume graph which is notoriously detached from reality/PIOMAS (most visible at the turning points), and an AMSR2 volume graph posted here from time to time. I don't have the links readily available at the moment, but should be easy to find.

45
Arctic sea ice / Re: The 2016/2017 freezing season
« on: March 09, 2017, 06:33:39 AM »
possibly in terms of extent, but certainly not the volume. should any 3-5m thick ice be flushed down the fram or elsewhere it cannot be re-plenished within a  month and not even within a year's time.

To some extent is not the thicker ice a result of thinner ice being pushed against the shore and piled up by wind and current?
It is, but in a process that takes years.

46
Consequences / Re: General Drought Stuff
« on: March 08, 2017, 11:59:47 PM »
Great. Let's drain Baikal like Aral.
Actually Aral is an inland sea and therefore easier to drain than Baikal, which is a pass-through lake. Therefore the main initial effect will be to lessen the outflow of the lake into the Angara river, and therefore less of a problem. Not saying this is a good plan, just that the consequences are somewhat different.

47
Arctic sea ice / Re: Latest PIOMAS update (March)
« on: March 08, 2017, 10:41:17 PM »
Nature Climate Change, Ice-free Arctic at 1.5 °C? James A. Screen & Daniel Williamson
The article is pay-walled, is anyone aware of an open access copy?


You can download it from the sci-hub website:

http://sci-hub.cc/10.1038/nclimate3248

There is a download button  (labeled: сохранить статью)  at the left of that page.

Thanks! Now bookmarked for future searches.

48
Greenland and Arctic Circle / Re: Wandel Sea / North East Greenland
« on: March 08, 2017, 10:15:12 PM »
The export machine keeps on humming.

49
Interestingly, the calving front barely advanced over the winter, although the glacier kept on going.

50
Arctic sea ice / Re: Latest PIOMAS update (March)
« on: March 08, 2017, 10:10:14 PM »
Jim, may I suggest to keep this thread to PIOMAS only, and leave the other content, whatever it may be, to different threads? 2017 open thread, conservative scientists and its consequences, I bet there are quite a few of those.

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