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Re: Arctic Sea Ice 2017 Pt. 1

Unread postPosted: Sun 03 Sep 2017, 11:43:05
by vtsnowedin

Re: Arctic Sea Ice 2017 Pt. 1

Unread postPosted: Wed 06 Sep 2017, 11:33:01
by vox_mundi
Unraveling a Major Cause of Sea Ice Retreat in the Arctic Ocean

Recently, ice-ocean "albedo feedback" has emerged as a key cause for sea ice melt. The feedback is generated by a large difference in albedo – a measure of light reflectivity – between open water and ice surfaces. As dark ocean surfaces absorb more light than white ice surfaces, solar heat input through the open water melts sea ice, increasing both open water areas and heat input and thus accelerating sea ice melt.

Analyzing the data from 1979 to 2014, the researchers found the solar heat input through open water surfaces correlated well with ice melt volume, suggesting heat input is a major causative factor of melting ice. This was particularly obvious after 2000, when there were considerable reductions in sea ice.

Accumulated heat input through open water surfaces in the surveyed area from May to August (red line) correlated well with interannual variations in ice melt volume (black line) between 1979 and 2014. Sea ice melt volume is converted to the heat input required for ice melt. Blue crosses and red circles indicate values before and after 2000, respectively.

In addition, divergent ice motion in the early melt season can be a trigger of ice melt acceleration through ice-ocean albedo feedback. After the 2000s, such relationship has likely become stronger, suggested by a much higher regression coefficient than that prior to 2000.

These results also suggest that ice motion in the early melt season may possess predictive skill in seasonal sea ice forecasts in this sector of the Arctic Ocean.

Schematic of ice and heat budgets during seasonal ice retreat. Divergent ice motion in the early melt season induces a small reduction in ice concentration (upper panel). A key finding is that although the direct contribution of doubled divergent ice motion after 2000 to the ice concentration reduction is small, this trigger accelerates ice melt through the enhanced solar heat input over the open water fraction (ice-ocean albedo feedback) until the end of August (lower panel).

Haruhiko Kashiwase et al. Evidence for Ice-Ocean Albedo Feedback in the Arctic Ocean Shifting To a Seasonal Ice Zone, Scientific Reports (2017)

Good news

Unread postPosted: Wed 13 Sep 2017, 05:35:35
by Whitefang
Good news from up North:

It seems my prayers from May have been heard:

There's nothing else to do but hope that PIOMAS has it completely wrong, or else pray for lots of cold and cloudy weather in the Arctic this summer.

Well, the weather did its thing and produced one of the biggest turnarounds in the Arctic I have seen so far. I mean, in 2013 the ice managed to return from the brink of death, so to say, but at least the winter preceding it had been very cold. This year the melting season started with a record low volume after an incredibly mild winter.

One consequence of that mild winter, however, was lots of snowfall on the ice and adjacent land masses (see here). This snow likely managed to reflect some of the sunny weather that creates what I call melting momentum during May and June. So, with snow melting out late and not much melting momentum to speak of (yet again), it all came down to what kind of weather we'd be seeing during July and August. Cue low pressure.

Re: Arctic Sea Ice 2017 Pt. 1

Unread postPosted: Thu 14 Sep 2017, 11:57:28
by Cid_Yama
With the coolest and least eventful, storm wise, summer we have had, we still are among the lowest on area and extent. But volume is still declining. Volume is 70% below 1979. Most of that lost after 2003.

Area and extent dominated by spreading slush does not bode well. Remember what those numbers represent. >15% sea ice. Set that at >50% and it tells a whole different story.

There is nothing hopeful going on, we are losing the ice rapidly. We just managed to dodge the bullet this year, area and extent wise. But not volume wise.

Re: Arctic Sea Ice 2017 Pt. 1

Unread postPosted: Fri 15 Sep 2017, 07:58:15
by Whitefang
Using piomas for volume, now at around 5000 cubic km, min level of 2011 and 2015. Not at record low of 2012, more or less 4000 ckm.
Still 7000 ckm under the mean of 1979/2016, which mean volume is already far below normal for having reached a tipping point last decade.
Will probably make for third lowest on record. ... 128970c-pi

Re: Arctic Sea Ice 2017 Pt. 1

Unread postPosted: Fri 15 Sep 2017, 10:23:43
by Cid_Yama
Average Arctic sea ice volume through Aug 2017 was 5.5 km3 a bit above the record of 2012 (5.0 km3). August 2017 volume was 70% below the maximum August ice volume in 1979, 56% below the 1979-2016 mean, and about 0.4 standard deviations below the long term trend line. While 2017 started well below prior years and remained so through May, ice loss during June through August was less than previous years. This is shown in Fig 8 which compares daily ice volume anomalies for several recent years (base period 1979-2016). The difference between 2012 (the previous record) is notable. While 2017 started out with much lower sea ice volume, 2012 had a much more rapid sea ice loss through May and June. Both 2012 and 2017 have very similar anomaly progression through July. August 2017 by comparison was a month of reprieve relative to 2012.


The chart you are referring to only shows through mid-August. You can see a larger version by clicking on it at the link. At that time, 2017 had just allowed 2011 to catch up and was tied for second behind 2012. (that line you mistook for 2015 is actually 2010, 2015 is up between 2014 and 2013. 2016 is hidden behind the 2010 line in mid August, and achieved lowest in mid September.) 2013-2014 had seen an increase in volume from 2012, but we have since lost that volume again, rapidly since 2014, with a huge drop between 2015 and 2016.

Here is a short 3D representation that really puts it across.

No hope but buying time before the inevitable decline

Unread postPosted: Sat 16 Sep 2017, 06:42:28
by Whitefang
Ok Cid, thanks for clearing that up.

I agree there is no hope for sea ice up North but we are given an extra year of a near normal winter ice cover...I hope so as what we, everybody needs is time.
No hope long term for any natural ice/permafrost/snowcover on Earth I suppose, a direct result of abruptly flipping into a hothouse instead of swinging between glacial times.
Mt Vinson and that high one, Denali might be the last place sometime in the future to find glaciers.
I bet those glaciers in Africa are already toast, Kilimanjaro.....
Way, way of topic, 70 degrees of wonderful Earth.

Here you go, race against time: ... anda-congo

Ptolemy thought they were the source of the Nile and called them the Mountains of the Moon because of the perpetual mists that covered them; Stanley claimed to be the first non-African to see their icecap; and the many thousands of subsistence farmers who today live on the slopes of the fabled Rwenzori mountains in Uganda and the Democratic Republic of the Congo fear that warming temperatures are devastating their harvests.

While 20,000 people a year scale Mount Kilimanjaro in Tanzania, just a handful of trekkers tackle the lower, 5,100m Rwenzori summits and witness the spectacular plant forms that grow in some of the wettest conditions on Earth. The result is that little is known about the condition of the many tropical glaciers that descend off the three peaks of mounts Baker, Speke and Africa's third highest peak, Mount Stanley.

But last month, a micro-expedition led by London-based Danish photographer Klaus Thymann returned from Uganda with the best evidence yet that the 43 glaciers found and named in 1906 are still mostly there, but are in dire condition and can be expected to disappear in a decade or two. ... nking.html

SAN FRANCISCO — Kilimanjaro's shrinking northern glaciers, thought to be 10,000 years old, could disappear by 2030, researchers said here yesterday (Dec. 12) at the annual meeting of the American Geophysical Union.
The entire northern ice field, which holds most of Kilimanjaro's remaining glacial ice, lost more than 140 million cubic feet (4 million cubic meters) of ice in the past 13 years, said Pascal Sirguey, a research scientist at the University of Otago in New Zealand. That's a cube measuring roughly 520 feet (158 m) on each side.
The loss in volume is approximately 29 percent since 2000, while the total surface area lost is 32 percent, Sirguey said. Last year, the ice field split in two, revealing ancient lava that may not have seen the sun for millennia. [Video: Kilimanjaro's Shrinking Glaciers]

Looks like they are still there but not for long, and those people studying the glaciers are not likely to have taken into account the recent stage of abrupt CC.

Re: Arctic Sea Ice 2017 Pt. 1

Unread postPosted: Thu 21 Sep 2017, 13:22:59
by dolanbaker
Move along now, nothing to see here. Looks like the minimum extent was nothing to write home about, no catastrophic collapse in area that many here predicted.

Re: Arctic Sea Ice 2017 Pt. 1

Unread postPosted: Thu 21 Sep 2017, 13:28:35
by dolanbaker
onlooker wrote:You deniers are really stretching your denial here. Anyone with a working brain can see something very anomalous is happening in the Arctic now. Like being on the verge of a relatively ice free Arctic sea. Duh.

Looked no worse than it has been for the past few years, a fairly unremarkable minimum when compared to some of the recent lows.

Re: Arctic Sea Ice 2017 Pt. 1

Unread postPosted: Fri 22 Sep 2017, 00:16:00
by Cid_Yama
Here. You obviously missed this.

Re: Arctic Sea Ice 2017 Pt. 1

Unread postPosted: Fri 22 Sep 2017, 01:55:44
by dolanbaker
That's last years news.

Re: Arctic Sea Ice 2017 Pt. 1

Unread postPosted: Fri 22 Sep 2017, 11:03:55
by Cid_Yama
Your kidding me right. Volume continues to drop regardless of the extent of the spreading slush that was left. A child could see the overall trend.

Re: Arctic Sea Ice 2017 Pt. 1

Unread postPosted: Fri 22 Sep 2017, 12:10:30
by dolanbaker
Cid_Yama wrote:Your kidding me right. Volume continues to drop regardless of the extent of the spreading slush that was left. A child could see the overall trend.

You are of course assuming that trend lines can only go in one direction, climate history has proven time and time again that they generally don't. Most trends in climate are cyclical in nature.

For example.

Sea ice extents & volumes are no different.

Re: Arctic Sea Ice 2017 Pt. 1

Unread postPosted: Sat 23 Sep 2017, 00:45:33
by dohboi
yeeeaaaahhhhh.....over a long enough time frame, I guess just about everything is more or less cyclical...

But right now we are at the start of a very, very long trend that is going in one very clear (to those who have some kind of eyes to see) direction.

It will probably someday cycle back. But given the long time it takes for carbon to be reseqestered...that's gonna be one heckofalong cycle this time...

cycle mania

Unread postPosted: Sat 23 Sep 2017, 07:36:52
by Whitefang
DB is right, ice ages come and go. 5 times in the past and the greenhouse state is the normal, two long periods from birth of Earth 4540 to 2900 Mya and 2100 to 720Mya, that means no ice for over 3 Billion years.

Not sure if ice is ever to come back at all though, life expectancy of Earth is what? Until the sun goes bang, fuel runs out?
Even if life is restored after an abrupt change of climate, within 5 to 9 million years, why would ice return some day?
All ice ages were in times of abundant plant/plancton life right?

There have been five known ice ages in the Earth's history, with the Earth experiencing the Quaternary Ice Age during the present time. Within ice ages, there exist periods of more severe glacial conditions and more temperate referred to as glacial periods and interglacial periods, respectively. The Earth is currently in such an interglacial period of the Quaternary Ice Age, with the last glacial period of the Quaternary having ended approximately 11,700 years ago with the start of the Holocene epoch.[1] Based on climate proxies, paleoclimatologists study the different climate states originating from glaciation. ... ouse_Earth

Currently, the Earth is in an icehouse climate state. About 34 million years ago, ice sheets began to form in Antarctica; the ice sheets in the Arctic did not start forming until 2 million years ago.[5] Some processes that may have led to our current icehouse may be connected to the development of the Himalayan Mountains and the opening of the Drake Passage between South America and Antarctica.[citation needed] Scientists have been attempting to compare the past transitions between icehouse and greenhouse, and vice versa to understand where our planet is now heading.

Without the human influence on the greenhouse gas concentration, the Earth would be heading toward a glacial period. Predicted changes in orbital forcing suggest that in absence of human-made global warming the next glacial period would begin at least 50,000 years from now[18] (see Milankovitch cycles).

But due to the ongoing anthropogenic greenhouse gas emissions, the Earth is instead heading toward a greenhouse earth period.[5] Permanent ice is actually a rare phenomenon in the history of the Earth, occurring only during the 20% of the time that the planet is under an icehouse effect.

The biological and geological future of Earth can be extrapolated based upon the estimated effects of several long-term influences. These include the chemistry at Earth's surface, the rate of cooling of the planet's interior, the gravitational interactions with other objects in the Solar System, and a steady increase in the Sun's luminosity. An uncertain factor in this extrapolation is the ongoing influence of technology introduced by humans, such as climate engineering,[2] which could cause significant changes to the planet.[3][4] The current Holocene extinction[5] is being caused by technology[6] and the effects may last for up to five million years.[7] In turn, technology may result in the extinction of humanity, leaving the planet to gradually return to a slower evolutionary pace resulting solely from long-term natural processes.

During the next four billion years, the luminosity of the Sun will steadily increase, resulting in a rise in the solar radiation reaching the Earth. This will result in a higher rate of weathering of silicate minerals, which will cause a decrease in the level of carbon dioxide in the atmosphere. In about 600 million years from now, the level of CO2 will fall below the level needed to sustain C3 carbon fixation photosynthesis used by trees. Some plants use the C4 carbon fixation method, allowing them to persist at CO
2 concentrations as low as 10 parts per million. However, the long-term trend is for plant life to die off altogether. The extinction of plants will be the demise of almost all animal life, since plants are the base of the food chain on Earth.[11]

Looks pretty grim for ice, even water on Earth, let alone life.

Continental drift is doing its thing:

To the south, the migration of Antarctica to the north will cause all of its ice sheets to melt. This, along with the melting of the Greenland ice sheets, will raise the average ocean level by 90 m (300 ft). The inland flooding of the continents will result in climate changes.[46]

As this scenario continues, by 100 million years from the present the continental spreading will have reached its maximum extent and the continents will then begin to coalesce. In 250 million years, North America will collide with Africa while South America will wrap around the southern tip of Africa. The result will be the formation of a new supercontinent (sometimes called Pangaea Ultima), with the Pacific Ocean stretching across half the planet. The continent of Antarctica will reverse direction and return to the South Pole, building up a new ice cap.[51

Re: Arctic Sea Ice 2017 Pt. 1

Unread postPosted: Sat 23 Sep 2017, 08:04:15
by dissident
dolanbaker wrote:
Cid_Yama wrote:Your kidding me right. Volume continues to drop regardless of the extent of the spreading slush that was left. A child could see the overall trend.

You are of course assuming that trend lines can only go in one direction, climate history has proven time and time again that they generally don't. Most trends in climate are cyclical in nature.

For example.

Sea ice extents & volumes are no different.

Cherry picking BS. Geophysical fluid systems exhibit both oscillatory and secular trends. Only full on morons would believe that a secular change in the composition of the atmosphere, and hence radiative transfer, would produce no secular trend in temperature.

This discussion about sea ice extent is mind numbing idiocy. As pointed out above, some slush floating on the surface is considered "sea ice cover". Given that the Arctic Sea is in the polar cap region there will always be some such slush, especially in winter. Global warming does not require every square inch of the planet to have above freezing temperatures. Ice will be forming in the Arctic, even 1000 years from now after Greenland fully melts and the tropics become uninhabitable.

Re: Arctic Sea Ice 2017 Pt. 1

Unread postPosted: Sat 23 Sep 2017, 08:06:33
by dohboi
NYT has a piece on the situation now:

"Climate Change’s Effect on Arctic Sea Ice, in 3 Charts"

I've run through my monthly allotment of articles I can access there, but if someone else hasn't, perhaps they could provide the link and some text?

Re: Arctic Sea Ice 2017 Pt. 1

Unread postPosted: Sat 23 Sep 2017, 22:04:46
by Cid_Yama
Whitefang, from the context, you were obviously taking about Dohboi, but DolanBaker is also DB.


Unread postPosted: Sun 24 Sep 2017, 06:06:21
by Whitefang
Yeah Cid, funny mix up, I noticed too late to make amends, edit my post.
I am a lazy bum though, couch is king watching discovery on Alaska, bush people, primal survivor etc.
So much to do and see, so little time, a constant battle to do what is right.
I am an expert procrastinator :oops:

Looks like the arctic really is our Achilles heel with abrupt CC, everything stands by a healthy ice pack, our stable climate and thus food, fresh water for animals including humanity.
Plain incredible that Earth is so sensitive to a few hundred extra ppm CO2 and ppb CH4.

Really gives a feeling of watching the water on a beach recede before a tsunami, storm surge. We have simply run out of time.
We should be thankfull for any extra year of BAU, strive for excellence, whatever you do, spend that quality time with family. ... es-1.21431

“It is really the tail that wags the dog of global climate,” says Brenda Ekwurzel, director of climate science at the Union of Concerned Scientists in Cambridge, Massachusetts.

Blue period

Pfirman remembers the first time she realized just how fast the Arctic was unravelling. It was September 2007, and she was preparing to give a talk. She went online to download the latest sea-ice maps and discovered something disturbing: the extent of Arctic ice had shrunk past the record minimum and was still dropping. “Oh, no! It’s happening,” she thought.
Although Pfirman and others knew that Arctic sea ice was shrinking, they hadn’t expected to see such extreme ice losses until the middle of the twenty-first century. “It was a wake-up call that we had basically run out of time,” she says.

In theory, there’s still a chance that the world could prevent the total loss of summer sea ice. Global climate models suggest that about 3 million square kilometres — roughly half of the minimum summer coverage in recent decades — could survive if countries fulfil their commitments to the newly ratified Paris climate agreement, which limits global warming to 2 °C above pre-industrial temperatures.

But sea-ice researchers aren’t counting on that. Models have consistently underestimated ice losses in the past, causing scientists to worry that the declines in the next few decades will outpace projections2. And given the limited commitments that countries have made so far to address climate change, many researchers suspect the world will overshoot the 2 °C target, all but guaranteeing essentially ice-free summers (winter ice is projected to persist for much longer).
In the best-case scenario, the Arctic is in for a 4–5 °C temperature rise, thanks to processes that amplify warming at high latitudes, says James Overland, an oceanographer at the US National Oceanic and Atmospheric Administration in Seattle, Washington. “We really don’t have any clue about how disruptive that’s going to be.”


Unread postPosted: Sun 24 Sep 2017, 07:11:29
by Whitefang ... watch.html

Request of Brother D, Dohboi that is.

The 2017 minimum could have been even lower. Scientists look closely at both the maximum extent each winter and the minimum in summer. Arctic ice set a record-low maximum extent of 5.6 million square miles this March, following an exceedingly warm winter. But a record maximum does not necessarily translate to a record minimum: cooler temperatures this summer reduced the amount of melting, keeping the ice extent well above the record low, which was set in 2012.
“What happened is that weather patterns got in the way,” said Mark Serreze, director of the center. “This is part of the natural variability in the system.”
Regional ice patterns vary as well. Ice in the Beaufort Sea, north of Alaska, has retreated during summers for years now.

This year the melting was even more widespread. “You had open water extending almost 80 degrees north – way the heck out there,” Dr. Serreze said.

Wonder if that guy sailing to the pole made it, probably not. ... -much-ice/

Next time better! hihi,lol.

Arctic Mission’s furthest North was 80 degrees 10 minutes North, 148 degrees 51 minutes West, reached at 22:04:12 (Alaskan Time, GMT-9hours) on 29 August 2017 by yachts, Bagheera and Snow Dragon II.

Arctic Mission moored its yachts to an ice floe on 29 August to conduct one of its 24-hour marine science surveys, while drifting with the sea ice. The strategy for any future northward progress had been to monitor the sea surface currents, sea ice, and weather conditions (both observed from the yachts and through satellites imagery downloaded onto our computers), and decide how to proceed as we approached the end of the 24-hour survey.

A meeting of the four skippers was held led by Erik de Jong, with Pen Hadow present, and it was agreed further northward progress would increase considerably the risks to the expedition, with very limited scientific reward. The decision to head south, back to an area of less concentrated sea ice in the vicinity of 79 degrees 30 minutes North, was made at 18.30 (Alaskan time).

Arctic Mission has demonstrated that commercial fishing and shipping vessels can now access and exploit a new, unexplored and vulnerable ocean region on the planet, the Central Arctic Ocean, due to the melting of its sea-ice cover. Approximately 1 million square kilometres of the Central Arctic Ocean is likely to have been ice-free this summer, having had year-round ice cover throughout human history until the 1980s, and likely has had for many tens of thousands of years.