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Arctic Sea Ice Extent, Area, and Volume


ORH_wxman
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2 hours ago, WidreMann said:

Yes, this one: https://forum.arctic-sea-ice.net/index.php?board=3.0

I had seen csnavywx post there, so I figured there was at least some legitimacy. But there's definitely an unnecessary amount of doom and gloom.

There's some good stuff in there if you just wade through all the hyperbole. Wipneus does a fantastic job on NSIDC area and extent data and piomas volume data...that's the main reason I visit the site at all. 

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13 hours ago, WidreMann said:

Yes, this one: https://forum.arctic-sea-ice.net/index.php?board=3.0

I had seen csnavywx post there, so I figured there was at least some legitimacy. But there's definitely an unnecessary amount of doom and gloom.

Yeah there's a lot of good info and analysis (and some bad analysis too)... you just have to take the predictions with a grain of salt and make your own inferences based on the information.

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19 hours ago, ORH_wxman said:

It is definitely weird that we saw an abrupt flip. I wish we knew what caused it. It seems to coincide with the formation of the deep cold pool anomaly in the North Atlantic sometime in spring of 2013 when the deep blocking from early that spring broke down. But I'm not sure what is cause and what is effect and also what is just reinforcing feedback. Probably some combo but interesting nonetheless. 

The hadgem model from Hadley center seemed to predict this on some level after 2012...which is a nice score by that model. 

Yeah, the HadGEM1 did a great job.

https://www.the-cryosphere.net/7/555/2013/

Mechanisms causing reduced Arctic sea ice loss in a coupled climate model
A. E. West, A. B. Keen, and H. T. HewittMet Office Hadley Centre, Exeter, UK
Received: 09 May 2012 – Discussion started: 18 Jul 2012
Revised: 04 Feb 2013 – Accepted: 18 Feb 2013 – Published: 26 Mar 2013
 
Abstract. The fully coupled climate model HadGEM1 produces one of the most accurate simulations of the historical record of Arctic sea ice seen in the IPCC AR4 multi-model ensemble. In this study, we examine projections of sea ice decline out to 2030, produced by two ensembles of HadGEM1 with natural and anthropogenic forcings included. These ensembles project a significant slowing of the rate of ice loss to occur after 2010, with some integrations even simulating a small increase in ice area. We use an energy budget of the Arctic to examine the causes of this slowdown. A negative feedback effect by which rapid reductions in ice thickness north of Greenland reduce ice export is found to play a major role. A slight reduction in ocean-to-ice heat flux in the relevant period, caused by changes in the meridional overturning circulation (MOC) and subpolar gyre in some integrations, as well as freshening of the mixed layer driven by causes other than ice melt, is also found to play a part. Finally, we assess the likelihood of a slowdown occurring in the real world due to these causes.
 
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1 hour ago, bluewave said:

Yeah, the HadGEM1 did a great job.

https://www.the-cryosphere.net/7/555/2013/

Mechanisms causing reduced Arctic sea ice loss in a coupled climate model
A. E. West, A. B. Keen, and H. T. HewittMet Office Hadley Centre, Exeter, UK
Received: 09 May 2012 – Discussion started: 18 Jul 2012
Revised: 04 Feb 2013 – Accepted: 18 Feb 2013 – Published: 26 Mar 2013
 
Abstract. The fully coupled climate model HadGEM1 produces one of the most accurate simulations of the historical record of Arctic sea ice seen in the IPCC AR4 multi-model ensemble. In this study, we examine projections of sea ice decline out to 2030, produced by two ensembles of HadGEM1 with natural and anthropogenic forcings included. These ensembles project a significant slowing of the rate of ice loss to occur after 2010, with some integrations even simulating a small increase in ice area. We use an energy budget of the Arctic to examine the causes of this slowdown. A negative feedback effect by which rapid reductions in ice thickness north of Greenland reduce ice export is found to play a major role. A slight reduction in ocean-to-ice heat flux in the relevant period, caused by changes in the meridional overturning circulation (MOC) and subpolar gyre in some integrations, as well as freshening of the mixed layer driven by causes other than ice melt, is also found to play a part. Finally, we assess the likelihood of a slowdown occurring in the real world due to these causes.
 

We are running below the trendline so can't give this prediction a gold star yet..  

SPIOMASIceVolumeAnomalyCurrentV2.1.png

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1 hour ago, chubbs said:

We are running below the trendline so can't give this prediction a gold star yet..  

 

The rate of losses did slow post 2012 relative to the rapid 2005-2012 decline rate. But the long term downward trend will continue.

https://theconversation.com/why-arctic-melting-will-be-erratic-in-the-short-term-35969

A new study I co-authored with a team of Canadian and American scientists, published in Nature Climate Change, highlights that the recent slower melt is a temporary, but not unexpected, deceleration. The complex climate models used to make projections of future climate also exhibit similar periods of little change and more rapid change in Arctic sea ice. The recent trends are well within the range of these expectations. We might even see a decade or more with little apparent change in sea ice.

The causes of these fluctuations in melt rate are still being explored. Onesuggestion is that slow variations in Atlantic sea surface temperatures are involved. More observations of the Arctic ocean, atmosphere and sea ice would help answer this question.

An ice-free future?

When will the Arctic be ice-free – or equivalently, when will the ball reach the bottom of the hill? The IPCC concluded it was likely that the Arctic would be reliably ice-free in September by 2050, assuming high future greenhouse gas emissions (where “reliably ice-free” means five consecutive years with less than 1 million km2 of sea ice).

We expect the long-term decline in Arctic sea ice to continue as global temperatures rise. There will also be further bounces, both up and down. Individual years will be ice-free sometime in the 2020s, 2030s or 2040s, depending on both future greenhouse gas emissions and these natural fluctuations.

 
 

 

 

 

 

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20 hours ago, bluewave said:

................................................................................We expect the long-term decline in Arctic sea ice to continue as global temperatures rise. There will also be further bounces, both up and down. Individual years will be ice-free sometime in the 2020s, 2030s or 2040s, depending on both future greenhouse gas emissions and these natural fluctuations.

 

This is a good summary. Every year is a roll of the dice but gradually the dice are being loaded. Recently winters have been the most problematic. Perhaps we will see some temporary sea ice rebound with reversion to more normal conditions this winter.

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29 minutes ago, skierinvermont said:

I know it's nitpicky but that last bar is no where near the line of best fit for that period (07-17). To get a flat trend like that you'd have to go from '10-'17.

I did it in 1 minute in Paint.NET, so it's going to be ****ty (and I did mean for it to be from '10-'17, but wasn't being careful). Also, that period is very tumultuous, so I don't think a linear trend from 2010-2017 is meaningful. We'll have to see how it looks after a few more years, especially after we recover from the super-Nino.

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Interesting chart from Wipneus on the ASIF today showing the area of various ice thicknesses on July 22. 2017 lags in the thinnest categories but leads in the thicker. Wipneus notes that 0.26 on July 22 always melts and 0.71 sometimes melts in severe late summers. So a range of outcomes is still possible this year depending on weather.

PIOMAS_area-thicknesscat_20170722.png_thumb.png

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sea levels falling?

https://www.iceagenow.info/sea-levels-are-falling/

maybe explains why new islands are forming near north carolina.

http://www.cnn.com/travel/article/new-island-north-carolina/index.html

funny too how the arctic flip occurred right after the election.  considering how severe the ice melt was during the beginning / middle of last winter, we 'should' be much lower by now.  Even ORH seemed perplexed from the flip.   (few pages back)

If there ever was a secret project to save the arctic ,we'd never hear about it anyway.  (too many would complain / troll about chemtrail or other experimental programs)

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3 hours ago, Sophisticated Skeptic said:

sea levels falling?

https://www.iceagenow.info/sea-levels-are-falling/

maybe explains why new islands are forming near north carolina.

http://www.cnn.com/travel/article/new-island-north-carolina/index.html

funny too how the arctic flip occurred right after the election.  considering how severe the ice melt was during the beginning / middle of last winter, we 'should' be much lower by now.  Even ORH seemed perplexed from the flip.   (few pages back)

If there ever was a secret project to save the arctic ,we'd never hear about it anyway.  (too many would complain / troll about chemtrail or other experimental programs)

The sea levels get really high and then level off for a year and you are saying they are falling? That graph shows a very noticeable and consistent upward trend for decades. Who cares if one year is more variable? We had a super-nino. Everything is a little messed up right now.

I don't know what "Arctic flip" you are talking about, but it was in sorry shape last summer and remains in sorry shape now. All that happened was that we had a slightly below normal May and June, so the degree of ice melt was less than we might have expected given the awful shape the Arctic ice is in. It's still way below normal and has been the whole season. Nothing changed drastically last November after the election, nor after Trump took office.

If you are going to have a real debate, at least use actual facts.

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http://news.trust.org/item/20170726060325-colqn

Scientists dim sunlight, suck up carbon dioxide to cool planet

OSLO, July 26 (Reuters) - Scientists are sucking carbon dioxide from the air with giant fans and preparing to release chemicals from a balloon to dim the sun's rays as part of a climate engineering push to cool the planet.

Backers say the risky, often expensive projects are urgently needed to find ways of meeting the goals of the Paris climate deal to curb global warming that researchers blame for causing more heatwaves, downpours and rising sea levels.

The United Nations says the targets are way off track and will not be met simply by reducing emissions for example from factories or cars - particularly after U.S. President Donald Trump's decision to pull out of the 2015 pact.

They are pushing for other ways to keep temperatures down.

In the countryside near Zurich, Swiss company Climeworks began to suck greenhouse gases from thin air in May with giant fans and filters in a $23 million project that it calls the world's first "commercial carbon dioxide capture plant".

Worldwide, "direct air capture" research by a handful of companies such as Climeworks has gained tens of millions of dollars in recent years from sources including governments, Microsoft founder Bill Gates and the European Space Agency.

If buried underground, vast amounts of greenhouse gases extracted from the air would help reduce global temperatures, a radical step beyond cuts in emissions that are the main focus of the Paris Agreement.

Climeworks reckons it now costs about $600 to extract a tonne of carbon dioxide from the air and the plant's full capacity due by the end of 2017 is only 900 tonnes a year. That's equivalent to the annual emissions of only 45 Americans.

And Climeworks sells the gas, at a loss, to nearby greenhouses as a fertiliser to grow tomatoes and cucumbers and has a partnership with carmaker Audi, which hopes to use carbon in greener fuels.

Jan Wurzbacher, director and founder of Climeworks, says the company has planet-altering ambitions by cutting costs to about $100 a tonne and capturing one percent of global man-made carbon emissions a year by 2025.

"Since the Paris Agreement, the business substantially changed," he said, with a shift in investor and shareholder interest away from industrial uses of carbon to curbing climate change.

But penalties for factories, power plants and cars to emit carbon dioxide into the atmosphere are low or non-existent. It costs 5 euros ($5.82) a tonne in the European Union.

And isolating carbon dioxide is complex because the gas makes up just 0.04 percent of the air. Pure carbon dioxide delivered by trucks, for use in greenhouses or to make drinks fizzy, costs up to about $300 a tonne in Switzerland.

Other companies involved in direct air capture include Carbon Engineering in Canada, Global Thermostat in the United States and Skytree in the Netherlands, a spinoff of the European Space Agency originally set up to find ways to filter out carbon dioxide breathed out by astronauts in spacecrafts.

NOT SCIENCE FICTION

The Paris Agreement seeks to limit a rise in world temperatures this century to less than 2 degrees Celsius (3.6 Fahrenheit), ideally 1.5C (2.7F) above pre-industrial times.

But U.N. data show that current plans for cuts in emissions will be insufficient, especially without the United States, and that the world will have to switch to net "negative emissions" this century by extracting carbon from nature.

Riskier "geo-engineering" solutions could be a backstop, such as dimming the world's sunshine, dumping iron into the oceans to soak up carbon, or trying to create clouds.

Among new university research, a Harvard geo-engineering project into dimming sunlight to cool the planet set up in 2016 has raised $7.5 million from private donors. It plans a first outdoor experiment in 2018 above Arizona.

"If you want to be confident to get to 1.5 degrees you need to have solar geo-engineering," said David Keith, of Harvard.

Keith's team aims to release about 1 kilo (2.2 lbs) of sun dimming material, perhaps calcium carbonate, from a high-altitude balloon above Arizona next year in a tiny experiment to see how it affects the microphysics of the stratosphere.

"I don't think it's science fiction ... to me it's normal atmospheric science," he said.

Some research has suggested that geo-engineering with sun-dimming chemicals, for instance, could affect global weather patterns and disrupt vital Monsoons.

And many experts fear that pinning hopes on any technology to fix climate change is a distraction from cuts in emissions blamed for heating the planet.

"Relying on big future deployments of carbon removal technologies is like eating lots of dessert today, with great hopes for liposuction tomorrow," Christopher Field, a Stanford University professor of climate change, wrote in May.

Jim Thomas of ETC Group in Canada, which opposes climate engineering, said direct air capture could create "the illusion of a fix that can be used cynically or naively to entertain policy ideas such as 'overshoot'" of the Paris goals.

But governments face a dilemma. Average surface temperatures are already about 1C (1.8F) above pre-industrial levels and hit record highs last year.

"We're in trouble," said Janos Pasztor, head of the new Carnegie Climate Geoengineering Governance Project. "The question is not whether or not there will be an overshoot but by how many degrees and for how many decades."

Faced with hard choices, many experts say that extracting carbon from the atmosphere is among the less risky options. Leaders of major economies, except Trump, said at a summit in Germany this month that the Paris accord was "irreversible."

"BARKING MAD

Raymond Pierrehumbert, a professor of physics at Oxford University, said solar geo-engineering projects seemed "barking mad".

By contrast, he said "carbon dioxide removal is challenging technologically, but deserves investment and trial."

The most natural way to extract carbon from the air is to plant forests that absorb the gas as they grow, but that would divert vast tracts of land from farming. Another option is to build power plants that burn wood and bury the carbon dioxide released.

Carbon Engineering, set up in 2009 with support from Gates and Murray Edwards, chairman of oil and gas group Canadian Natural Resources Ltd, has raised about $40 million and extracts about a tonne of carbon dioxide a day with turbines and filters.

"We're mainly looking to synthesise fuels" for markets such as California with high carbon prices, said Geoffrey Holmes, business development manager at Carbon Engineering.

But he added that "the Paris Agreement helps" with longer-term options of sucking large amounts from the air.

Among other possible geo-engineering techniques are to create clouds that reflect sunlight back into space, perhaps by using a mist of sea spray.

That might be used locally, for instance, to protect the Great Barrier Reef in Australia, said Kelly Wanser, principal director of the U.S.-based Marine Cloud Brightening Project.

Among new ideas, Wurzbacher at Climeworks is sounding out investors on what he says is the first offer to capture and bury 50 tonnes of carbon dioxide from the air, for $500 a tonne.

That might appeal to a company wanting to be on forefront of a new green technology, he said, even though it makes no apparent economic sense. ($1 = 0.9538 Swiss francs) ($1 = 0.8593 euros)

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On 7/25/2017 at 7:02 AM, chubbs said:

Interesting chart from Wipneus on the ASIF today showing the area of various ice thicknesses on July 22. 2017 lags in the thinnest categories but leads in the thicker. Wipneus notes that 0.26 on July 22 always melts and 0.71 sometimes melts in severe late summers. So a range of outcomes is still possible this year depending on weather.

PIOMAS_area-thicknesscat_20170722.png_thumb.png

I'm fairly convinced that if you start with this year's April volume and add a 2012 summer, you'd get damn close if not hit the 1M "near sea-ice free" criteria. It's taken a solid 2 months for 2012 to cut that lead down (though most of was during late May-June). Sept 2012 only had 2800km3 left at the min. Rob it of 2K in April in the thicker/colder areas like this year and that might be enough to tip the balance. It's not a high chance at this point by any means, but I think it's starting to cross the 5% threshold.

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Late month update on area....how other years compare to 2017:

2016: -300k

2015: -190k

2014: +340k

2013: +50k

2012: -520k

2011: -330k

2010: -110k

2009: +410k

2008: +350k

2007: -320k

 

We are closest to 2013 right now, but when you look at the numbers, it doesn't necessarily that means where we will end up. You can see that 2008 still had pretty high area at this point (350k ahead of 2017 and 300k ahead of 2013), but much of it was vulnerable ice in the Laptev so it melted back quite a bit in August....whereas a year like 2013 had already melted out most of the vulnerable ice so it stalled and finished significantly higher than a year like 2008. The next closest year is 2010. I still think a finish close to 2010 is probably the most likely right now. That year finished at 3.07 million sq km for area....though really anything plus or minus 200k from that is fair game.

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3 hours ago, ORH_wxman said:

Late month update on area....how other years compare to 2017:

2016: -300k

2015: -190k

2014: +340k

2013: +50k

2012: -520k

2011: -330k

2010: -110k

2009: +410k

2008: +350k

2007: -320k

 

We are closest to 2013 right now, but when you look at the numbers, it doesn't necessarily that means where we will end up. You can see that 2008 still had pretty high area at this point (350k ahead of 2017 and 300k ahead of 2013), but much of it was vulnerable ice in the Laptev so it melted back quite a bit in August....whereas a year like 2013 had already melted out most of the vulnerable ice so it stalled and finished significantly higher than a year like 2008. The next closest year is 2010. I still think a finish close to 2010 is probably the most likely right now. That year finished at 3.07 million sq km for area....though really anything plus or minus 200k from that is fair game.

Just to make sure I understand, when it says -320K, for example, it means 2007 had 320K less than 2017, or the other way around?

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18 hours ago, WidreMann said:

Just to make sure I understand, when it says -320K, for example, it means 2007 had 320K less than 2017, or the other way around?

You're correct...you can use the other years as baselines....higher ice years like 2009 and 2014 are larger positive values.

 

 

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It will be interesting to see if the September 2012 low extent record can remain in place into the early 2020's. Or if the dipole pattern makes a return in 18-19 finally allowing a new record minimum to be set. Not sure many in September 2012 though it would take so long to break the record.

 

5980750b332f8_Screenshot2017-08-01at8_24_27AM.png.adcbd9d36777e6040f74dd97deace404.png

 

 

 

 

 

 

 

 

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25 minutes ago, J Paul Gordon said:

Will the bottoming out of solar irradiation due to decreased sunspot activity affect sea ice minima in the Arctic basin?

The effect is too small to really make a difference. Maybe only 0.3 watts per meter sq in high amplitude cases....which might be like a tenth of a degree Celsius, but most likely the impact is less. If we had an extended min for like a decade or longer, then it might be somewhat noticeable.

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Solar activity (Jan-Dec sunspots via SILSO) is actually correlated pretty strongly with sea ice extent on August 1 in the Arctic going by http://nsidc.org/arcticseaicenews/charctic-interactive-sea-ice-graph/ but I think it is because the Sun & AMO flipped phases at similar times, i.e. the sun has weakened fairly consistently since the big solar years in the 1930s-1990s, and the 70s/80s/early 90s is when the AMO was cool, now it is warm.

 

Arctic Sea Ice (Aug 1) v. Sunspots Jan-Dec.PNG

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PIOMAS updated for August 1st....2017 has now relinquished its place for lowest volume to 2012 for the first time this year...albeit still very close. I think it is unlikely 2017 will be able to match 2012's losses from here on out, but if the weather is bad enough, who knows for sure.

 

 

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3 hours ago, ORH_wxman said:

PIOMAS updated for August 1st....2017 has now relinquished its place for lowest volume to 2012 for the first time this year...albeit still very close. I think it is unlikely 2017 will be able to match 2012's losses from here on out, but if the weather is bad enough, who knows for sure.

 

 

Doesn't the weather look favorable with a vortex near Alaska/Beaufort?

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23 minutes ago, nzucker said:

Doesn't the weather look favorable with a vortex near Alaska/Beaufort?

Yeah the vortex is mostly hanging out over the CAB...there's a pretty strong storm in the couple days...we'll see if that is strong enough to do any damage. But it is definitely not the typical pattern for huge melting out shown through mid-month.

The biggest enemy of the ice is how thin it was at the beginning of the year. If this pattern happened in 2015, we probably would have seen a minimum extent in the mid 5s.

 

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It's easy to just focus on the recent melt seasons but I got a jolt when I looked at the PIOMAS sea ice volume plot.  The SIV is currently around 6.75K km3, just behind 2012 as ORH reported above, but the 1979-2001 average for this time of years is almost 17,000 km3, more 10,000 km3 greater than today - a loss I find sobering.

piomas-trnd4.png?attachauth=ANoY7cotCUzO

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