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Messages - Juan C. García

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1
Antarctica / Re: PIG has calved
« on: December 09, 2019, 03:42:44 PM »
 “Merde” (nice French word), even side NSM it does not go too well!!

What to watch

Click to move !

2
Policy and solutions / Re: Greta Thunberg's Atlantic crossing
« on: December 09, 2019, 09:34:53 AM »
If you're interested.


In 1 hour time (at 10.30 in Madrid): LIVESTREAM

"Fridays For Future" with Greta and others

https://unfccc-cop25.streamworld.de/webcast/press-conference-by-greta-thunberg-luisa-neubauer-

3
Arctic sea ice / Re: Latest PIOMAS update (December 2019 )
« on: December 04, 2019, 11:39:10 AM »
Updated volume and volume-anomaly graphs. Click for the better picture.

4
Arctic sea ice / Re: Latest PIOMAS update (December 2019 )
« on: December 04, 2019, 11:29:36 AM »
PIOMAS has upgraded the gridded thickness data. Last date, 30th Nov, the calculated volume was 10.35[1000km3]. That is third lowest for the day (behind 2016 and 2012).

Here is the animation for November 2019.

5
Consequences / Re: Wildfires
« on: December 02, 2019, 09:14:29 PM »
Grandmother dumps burnt remains of home at Parliament House in climate change protest

Quote
A woman has brought the charred remains of her bushfire-ravaged home to Parliament House in Canberra, accusing both major political parties of failing to act on climate change.
...snip....
Ms Plesman, who is now living in a Grafton hotel, said she was furious when Mr Morrison offered prayers for victims.

"I lost my house, I lost my way of life — my whole community has — and while that was happening, the PM said that he didn't want us to talk about climate change, that this wasn't the time," she said.

"We weren't allowed to mention climate change and then [Mr Morrison] said that he was praying for us.

"I got really upset and really angry because I just felt that we needed a hell of a lot more than that.
https://www.abc.net.au/news/2019-12-02/bushfire-victim-nsw-nymboida-climate-change-protest/11757082


6
Policy and solutions / Re: UN Climate Agreement - Paris 2015 and beyond
« on: November 26, 2019, 09:28:59 PM »
The UNEP emissions gap report includes projections for fossil fuel production based on IEA and other projections (for the US, EIA) that are very friendly to the fossil fuel industry and not based in reality.

The chart for oil shows US oil production growing from the current record rate of 12.8 million barrels per day to almost double, 22 million barrels per day in 2030.  Meanwhile, frackers are going bankrupt as quickly as they can get to a courthouse to file papers.  Natural gas has such a huge supply glut that suppliers are talking about cutting production.

And less than a week after the doom and gloom report was published, we see a record drop in coal use for the year.

https://www.carbonbrief.org/analysis-global-coal-power-set-for-record-fall-in-2019

Quote
Global electricity production from coal is on track to fall by around 3% in 2019, the largest drop on record.

The UNEP Emissions Gap report assumes that electricity demand will continue to increase as much as it has in the past few years.  Meanwhile, China and India are seeing drops in electricity demand, in part because much of their investment in the past decade has been in coal plants, which are increasingly sitting idle.

Quote
In China, electricity demand growth has slowed to 3% this year, down from 6.7% over the past two years. Non-fossil energy sources have met almost all this demand growth.

Quote
However, 2019 has so far seen strong nuclear, wind and hydro power generation and relatively weak overall electricity demand growth, with coal use in electricity flatlining.

At the same time, Chinese power firms have been continuing to add new coal-fired power plants to the grid at a rate of one large plant every two weeks. This has driven coal-fired power plant utilisation rates – the share of hours in the year when they are running – back down to record lows of 48.6%. This is the fourth year in a row that the Chinese national average has been below 50% – and also below the global average, which stands at 54%.

Quote
Electricity demand growth in India has continued to slow dramatically across the first ten months of 2019. In October, electricity demand actually fell by 13.2% against the same month last year.

Quote
The average thermal power plant utilisation rate in India is below 58%, meaning substantial idle coal capacity.

Note that the UNEP Emissions Gap report assumes that once a fossil fuel plant is built, it will be used.  As China and India have shown, they instead sit idle while the electricity is generated from lower cost suppliers, like hydropower, solar and wind plants.


7
Policy and solutions / Re: UN Climate Agreement - Paris 2015 and beyond
« on: November 26, 2019, 02:36:34 PM »
UNEP have issued their 2019 emissions gap report.

Executive Summary - https://newclimate.org/wp-content/uploads/2019/11/EGR19ESEN.pdf
Full Report - https://newclimate.org/wp-content/uploads/2019/11/EGR2019.pdf

Press release - https://newclimate.org/2019/11/26/emissions-gap-report-2019/
Quote
Geneva, 26 November 2019 – unless global greenhouse gas emissions fall by 7.6 per cent each year between 2020 and 2030, the world will miss the opportunity to get on track towards the 1.5°C temperature goal of the Paris Agreement.

UNEP’s annual Emissions Gap Report says that even if all current unconditional commitments under the Paris Agreement are implemented, temperatures are expected to rise by 3.2°C, bringing even wider-ranging and more destructive climate impacts. Collective ambition must increase more than fivefold over current levels to deliver the cuts needed over the next decade for the 1.5°C goal.

Quote
“For ten years, the Emissions Gap Report has been sounding the alarm – and for ten years, the world has only increased its emissions,” said UN Secretary-General António Guterres.
“There has never been a more important time to listen to the science. Failure to heed these warnings and take drastic action to reverse emissions means we will continue to witness deadly and catastrophic heatwaves, storms and pollution.”[/size]

I think we are well and truly screwed.



8
Antarctica / Re: Thwaites Glacier Discussion
« on: November 26, 2019, 08:42:12 AM »
Here is one series of Sentinel-1 radar images of Iceberg B22-A.  This one has huge gaps, and I can probably find a longer series, but I think it makes a good representation.

There is a lot of back-and-forth motion from East to West.  It's almost like the iceberg is caught between the two shallow areas and is just drifting back and forth between them, with currents or the tide.  That movement is minor, roughly a kilometer, but it does seem to imply that B22-A is no longer firmly grounded.

Over time there is also a gradual counter-clockwise rotation to the North.  One could imagine that as B22-A bounces back and forth in a tight space it is also slowly working its way lose, although I still think it was a long way to go if it is going to work free without breaking up.

If it does break in two, the smaller halves might be less constrained and will have more freedom of motion to drift off.

This GIF has one image from March 8, 5 images from September 16 through October 10, and 5 more images from October 28 to November 21.  There is a pause before each gap and at the end.  The things to note are the gradual movement to the North (right to left) and small back-and-forth motions East and West (up and down.)  Also, it tends to pivot counter-clockwise around the Western (bottom) end.

9
Policy and solutions / Re: UN Climate Agreement - Paris 2015 and beyond
« on: November 25, 2019, 03:02:05 PM »
Our 2018 ´hindcast´:

Climate change: Greenhouse gas concentrations again break records

 in 2018 concentrations of CO2 reached 407.8 parts per million (ppm), up from 405.5ppm a year previously.

This increase was above the average for the last 10 years and is 147% of the "pre-industrial" level in 1750.

Methane is now at 259% of the pre-industrial level and the increase seen over the past year was higher than both the previous annual rate and the average over the past 10 years.

Nitrous oxide is emitted from natural and human sources, including from the oceans and from fertiliser-use in farming. According to the WMO, it is now at 123% of the levels that existed in 1750.

Last year's increase in concentrations of the gas, which can also harm the ozone layer, was bigger than the previous 12 months and higher than the average of the past decade.

What concerns scientists is the overall warming impact of all these increasing concentrations. Known as total radiative forcing, this effect has increased by 43% since 1990, and is not showing any indication of stopping.

...

"It is worth recalling that the last time the Earth experienced a comparable concentration of CO2 was three to five million years ago. Back then, the temperature was 2-3C warmer, sea level was 10-20m higher than now," said Mr Taalas.

For details see:
https://www.bbc.com/news/science-environment-50504131

10
Consequences / Re: Places becoming less livable
« on: November 21, 2019, 11:13:53 AM »
  Massive Mildura dust storm leaves Victorian town 'unliveable' amid 40C heat

Residents say such storms now occur on a weekly basis, as topsoil from drought-ravaged farms is blown through the town

https://www.theguardian.com/environment/2019/nov/21/victorian-town-mildura-unliveable-massive-dust-storm-40c-heat
  by Naaman Zhou

Excerpts:
Residents told Guardian Australia it was like a “wall of dust”, a danger to asthmatics, and “unliveable”. And, for many, it is not even the worst dust storm this year. In May residents reported a storm as the town’s worst in 40 years.

“This is bad but recently there have been probably been three or four a week.”

“I have been here for 10 years and have never experienced anything like this. We used to have a dust storm a year, this is now a weekly basis. At its worst I couldn’t see across the road. This time the heat, because it is 40C, coupled with the dust just made it unliveable. You couldn’t go outside.

“It is really concerning to have young children and to feel like you can’t leave your house. You’re kind of trapped.”

Appleby said the extended drought had devastated farming communities and made the dust storms more frequent.

“We haven’t seen rain in months. It is absolutely climate-induced. The drought in this region is crippling farmers. And the dust in the sky is that farmers’ topsoil. When you put it into perspective like that it is terrifying.”

Appleby, who also has a six-year-old in school, said it was scary to think that this would be the future for her children.

edit: added author

11
Policy and solutions / Policy and solutions in the Netherlands
« on: November 13, 2019, 03:41:41 PM »
I think it will be interesting to report on the current situation in the Netherlands.

For a long time we were not really doing to much to help the climate. Politicians preferred paper solutions to real hard caps because well that is easier for them. Then someone fought the specific law and the law in general won.

1 Nitrogen policy

A while ago, around 2015 IIRC they had to craft a new law to protect nature from nitrogen pollution. This was required because of a European Union law that had to be translated into national law.

Our genius politicians wrote a law were current emissions were compensated by fictitious future gains in controlling the pollution. This would not work as the EU law states that you actually have to do something and that is not the same as kicking the can down the road. We have some institute that advises about laws and they said then that the law was not good enough but it still got voted into an official law.

A lawsuit followed and off course the dutch government lost.

The courts decision meant that most nitrogen permits for building were invalid.
This meant that all kind of building projects can not start so this costs tons of money.

And the real solution is not easy.

They appointed a commission with Remkes as chairman. He is VVD (right liberals, dominant party now) and a former interior minister.

Some of the proposed solutions they came up with:
1) Big reduction in cattle breeding. We are very big in this. Worldwide number 2 exporter for some products which is ridiculous since we are so small. Or if you look at it in a different way that means we are hugely succesfull and efficient at it. It also makes us a lot of money.

Meausures could include buy outs of the less efficient (old) farms.

The farmers felt threatened so they went to the Hague to protest on the Malieveld (veld is field and malie is an old game, it is basically croquet-field and now the place were big protests go).

The CDA our christian centrist party which is also the traditional farmers party and the one with the minister of agriculture hated this off course.

2) A reduction of the speed limit. It is (or was but we get to that next post) 130 km/h for no good reason and reducing it is a sore point for the VVD. They got to raise the speedlimit as a reward for an election victory while it only costs money for new signs and killed some more people and contributed to more congestion overall. Lowering it is seen as a defeat. They should just frame it as finally doing something sensible.

Some weeks ago the construction workers also collected at the Malieveld for a demonstration.  And since not building costs a lot of money and leads to big problems later since much of the projects are for sorely needed housing something needed to be done. And they did lower the speed but more about that in the next post.

*

Just lowering the speed limit is probably not enough so we will have to do something with farming too.

But there are many other developments at the same time.

2

The court case of the kids vs the dutch government
is in the appeal stage. Dutch government lost the first round. They are appealing because they think they need some freedom to solve issues. You can read above how well that goes so it would be nice if they lose the appeal too.

Currently i have no idea about the timeline off that.

3

Closing the gas fields.


After years of extraction the earthquake damage in Groningen lead to the early closure of the big gas fields. This means we will have to compensate (NAM is already scouting small fields) and we will have to change much of our infrastructure. Basically almost everyone is on the gas net and we use it for heating and cooking.

We will have to build the new houses differently and we have to adapt many of the old ones.

There will be test areas and one of them should be near me.

4 Something with PFAS 

This is sort of the same problem as the nitrogen thing with a EU law an a local norm iirc but i will get back to that.

5) Adapting the grid

The grid is built to where the power was needed historically which means that it is not strong enough in the periphal regions to tie up all solar projects that people want to develop.

*

I have quite a collection of newspaper articles and reactions by the readers so i will have to sort them by time and by issue.

All kinds of interesting things pop up. For example at the german side of the border they get a subsidy to convert from coal to gas while on the dutch side we are removing the gas.

It will be interesting to see how the debate goes in this stamp of a country.
Plenty of action (hopefully helpful) up ahead.


 

12
Consequences / Re: Places becoming less livable
« on: November 13, 2019, 11:54:47 AM »
Venice Underwater as Exceptional Tide Sweeps Through Canal City
https://phys.org/news/2019-11-venice-underwater-exceptional-tide-canal.html

Venice was hit by the highest tide in more than 50 years late Tuesday, with tourists wading through flooded streets to seek shelter as a fierce wind whipped up waves in St. Mark's Square.

The exceptionally intense "acqua alta," or high waters, peaked at 1.87 metres (six feet) as the flood alarm sounded across the Italian city of canals, the tide monitoring centre said.

Only once since records began in 1923 has the water crept even higher, reaching 1.94 metres in 1966.

The exceptional flood, which he blamed on climate change, was "a wound that will leave a permanent mark".



... Water taxis attempting to drop people off at the glamorous and historic hotels along the Grand Canal discovered the gangways had been washed away, and had to help passengers clamber through windows.

At the sumptuous Gritti Palace, which has played host to royals and celebrities over the decades, including Ernest Hemingway, Elizabeth Taylor and Richard Burton, the decadent bar was largely underwater.

Rich tapestries were piled onto tables, while the waters lapped around velvet sofas and leather-bound books.



... Pierpaolo Campostrini, a member of St. Mark's council, said the scale of the flooding on Tuesday had only been seen five times in the long history of the basilica, where construction began in 828 and which was rebuilt after a fire in 1063.

Most worryingly, Campostrini said, three of those five episodes occurred in the last 20 years, most recently in 2018.

13
Permafrost / Re: Permafrost general science thread
« on: November 11, 2019, 01:58:17 AM »
Arctic Shifts To a Carbon Source Due to Winter Soil Emissions
https://eurekalert.org/pub_releases/2019-11/nsfc-ast110819.php

A NASA-funded study suggests winter carbon emissions in the Arctic may be adding more carbon into the atmosphere each year than is taken up by Arctic vegetation, marking a stark reversal for a region that has captured and stored carbon for tens of thousands of years.

The study, published Oct. 21 in Nature Climate Change, warns that winter carbon dioxide loss from the world's permafrost regions could increase by 41% over the next century if human-caused greenhouse gas emissions continue at their current pace. Carbon emitted from thawing permafrost has not been included in the majority of models used to predict future climates.

"These findings indicate that winter carbon dioxide loss may already be offsetting growing season carbon uptake, and these losses will increase as the climate continues to warm," said Woods Hole Research Center Arctic Program Director Sue Natali, lead author of the study. "Studies focused on individual sites have seen this transition, but until now we haven't had a clear accounting of the winter carbon balance throughout the entire Arctic region."

Researchers estimate a yearly loss of 1.7 billion metric tons of carbon from the permafrost region during the winter season from 2003 to 2017 compared to the estimated average of 1 billion metric tons of carbon taken up during the growing season. ... "The warmer it gets, the more carbon will be released into the atmosphere from the permafrost region, which will add to further warming," ... . If fossil fuel use is modestly reduced over the next century, winter carbon dioxide emissions would increase 17% compared with current emissions. Under a scenario where fossil fuel use continues to increase at current rates through the middle of the century, winter carbon dioxide emissions from permafrost would rise by 41%.

Reposted here because it is a rather significant find about permafrost.

Abstract:
https://www.nature.com/articles/s41558-019-0592-8

Stuff that was bolded not long ago.

We predict that the PCF will change the arctic from a carbon sink to a source after the mid‐2020s


Well that failed.

Furthermore, there is high confidence that climate scenarios that involve mitigation (e.g. RCP4.5) will help to dampen the response of carbon emissions from the Arctic and boreal regions.


What really helps if you force the world onto that path. Or something even better.

Basically there is only one important scenario, the one we call the world.

We should go zero quicker and more coordinated and employ a bunch of cheap sensible carbon capture techniques ASAP which is ofc not going to happen.

The earlier 2020 date triggered me because one of the goals always was to prevent things like this from happening and now it is already here.

Eyeballing Mauna Loa CO2 anything over 370 is bad. So that is an interesting challenge.

14
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: October 30, 2019, 08:06:16 AM »
I attach three tables which show the number of days sea ice extent has been below 5M, 6M and 7M km2 around the minimum in a year.
  • 2019 extent was < 5M km2 for 64 days, which is the second highest amount, just 1 day behind 2012.
  • 2019 extent was < 6M km2 for 86 days, which beats the old record of 77 days set by 2007 & 2012 by a big margin.
  • 2019 extent was < 7M km2 for 100 days, which is the tied record together with 2016.

15
Antarctica / Re: PIG has calved
« on: October 28, 2019, 05:13:53 AM »
Here are two close-up Sentinel-1 radar images of the margin between Pine Island Glacier (PIG) and the Southern Ice Shelf (SIS) from April 11 and October 26, 2019, and a GIF comparing the two so movement can be more easily seen.

I've labeled the first image to show the areas that are considered to be the PIG, SIS, and the South West Tributary (SWT.)  They are all part of one big ice shelf, but they move relative to one another so it is important to make the distinction.  The Southern Shear Margin (SSM) rift is the continuation of a rift that started 60km upstream in 1999.  I show that the rift ends short of the ice front.

There is calving from the SIS where it meets the SSM rift.  I think it is reasonable to assume that when the rift reaches the ice front that the "melange" of ice from the calving will eventually float off and we may see additional calving from the SIS causing a retreat of the calving front into the SIS.

I do think that Stephen is correct to call the terminal iceberg a cork, although if the PIG calves it will become a moot point.   It is probably safe to say that within the next six months that either the PIG will calve or the cork will "pop."

But I do not see the SSM rift or the SIS calving as a threat to PIG since the northern margin is faster that the southern and it drives the calving of PIG.  It is however potentially a threat to the SIS and the South West Tributary.

16
Consequences / Re: Wildfires
« on: October 27, 2019, 01:19:00 PM »
Thousands of Homeowners in Fire Zones are Losing Their Insurance
https://abc7news.com/amp/insurance-companies-refusing-policies-in-wildfire-areas/5647865/

ORINDA, Calif. (KGO) -- It's getting harder for thousands to find fire insurance. The disastrous blazes have insurance companies dropping customers living in wildfire areas-- and many new homeowners can't buy a policy in a wildfire area.

The state Department of Insurance released some astonishing figures. Insurance companies refused to renew more than 167,000 homeowner policies last year.

That's up six percent statewide -- and up 10 percent in wildfire areas alone. Statistics show about nine thousand residents in disaster zones lost their homeowners insurance in 2018. They were living in or near one of the major fires of the past two years. Also, state officials say an estimated 88,000 homeowners living in fire-prone areas -- that is rural, wooded, hot and windy -- lost their coverage last year even if there was no actual fire near them.

17
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: October 20, 2019, 08:35:38 AM »
Compared to the 2010s average 2019 is 10 days behind, compared to the 2000s average 2019 is 31 days behind. A comparison with the 1990s and the 1980s is not possible, because their minima are higher than today's value.

18
Climate crisis will not be discussed at G7 next year, says Trump official
https://www.theguardian.com/world/2019/oct/17/g7-summit-2020-trump-climate-crisis

The climate crisis will not be formally discussed at the G7 summit in June next year in Miami, Donald Trump’s acting White House chief of staff said on Thursday.

“Climate change will not be on the agenda,” Mick Mulvaney told reporters, without elaborating.

Quote
... “It’s deeply ironic that the US state most vulnerable immediately to climate change impacts will host a meeting at which global leaders will be forced by the US to largely ignore the topic”

Mulvaney announced that the 2020 summit of seven of the world’s most powerful industrialised countries will take place at the National Doral Miami, one of the president’s golf resorts in Florida, despite widespread ethics concerns and an ongoing impeachment inquiry into Trump’s conduct.

19
Consequences / Re: Hurricane Season 2019
« on: October 15, 2019, 09:20:15 PM »
2,667 Bags of Radioactive Waste From Fukushima Nuke Disaster Washed Away by Typhoon Hagibis
https://www.taiwannews.com.tw/en/news/3795303

TAIPEI (Taiwan News) — As Typhoon Hagibis hammered Japan on Saturday (Oct. 12), thousands of bags containing radioactive waste have reportedly been carried into a local Fukushima stream by floodwaters, potentially having a devastating environmental impact.

According to Asahi Shimbun, a temporary storage facility containing some 2,667 bags stuffed with radioactive contaminants from the 2011 Fukushima Daiichi nuclear disaster was unexpectedly inundated by floodwaters brought by Typhoon Hagibis. Torrential rain flooded the storage facility and released the bags into a stream 100 meters away.

Officials from Tamara City in Fukushima Prefecture said that each bag is approximately one cubic meter in size. Authorities were only able to recover six of the bags by 9 p.m. on Oct. 12, and it is uncertain how many remain on the loose while the possible environmental impact is being assessed.

... In Hakone, in Kanagawa Prefecture, 37.1 inches of rain fell in 24 hours on Saturday, setting a record for that location, according to the Japan Meteorological Agency. In addition, 27 inches fell in heavily forested Shizuoka Prefecture southwest of Tokyo. In higher elevations just west of downtown Tokyo, 23.6 inches of rain fell, which was also a record.

20
Consequences / Re: Hurricane Season 2019
« on: October 14, 2019, 11:04:44 PM »
Global Warming and Hurricanes
An Overview of Current Research Results
F. Summary for Atlantic Hurricanes and Global Warming
Quote
In summary, neither our model projections for the 21st century nor our analyses of trends in Atlantic hurricane and tropical storm activity support the notion that greenhouse gas-induced warming leads to large increases in either tropical storm or overall hurricane numbers in the Atlantic. While one of our modeling studies projects a large (~100%) increase in Atlantic category 4-5 hurricanes over the 21st century, we estimate that such an increase would not be detectable until the latter half of the century, and we still have only low confidence that such an increase will occur in the Atlantic basin, based on an updated survey of subsequent modeling studies by our and other groups.    A recent study finds that the observed increase in an Atlantic hurricane rapid intensification metric over 1982-2009 is highly unusual compared to one climate model’s simulation of internal multidecadal climate variability, and is consistent in sign with that model’s expected long-term response to anthropogenic forcing.   These climate change detection results for rapid intensification metrics are suggestive but not definitive, and more research is needed for more confident conclusions.
https://www.gfdl.noaa.gov/global-warming-and-hurricanes/
Absence of  95% conclusive  evidence that it is happening is not the same as evidence it is not happening.
The physics of tropical cyclones  suggest warmer seas will result in stronger storms .
Physics  also suggests we will see warm core storms migrate poleward as the oceans warm .
Both of these effects are already apparent in what reliable data we have.
Waiting for such effects to hit an arbitrary level of statistical significance before we act means we would be  to far along to halt the changes. 



 

21
Antarctica / Re: Thwaites Glacier Discussion
« on: October 14, 2019, 08:45:51 PM »
I think it's time for an overview of the whole ice front of Thwaites Glacier so the discussion of various areas can be put in context.  The image below is from October 4 and I discuss the major sections from top to bottom (East to West.)  The image size is 112 km on a side and the width of the front as a whole is about 120 km.

Eastern Calving Front:  This is my designation.  It is usually considered to be part of the Eastern Ice Shelf, but this section does not seem to be directly pinned to the offshore ridge.  However it is slow moving because the ice behind it is probably affected by the pinned ice shelf.

Eastern Ice Shelf:  Ice that is caught directly between the glacier behind it and the undersea ridge in front of it.  This shelf was found to have thinned from 10 to 33 percent between 1978 and 2009 after early films of ice penetrating radar were recently digitized.

Melange:  Irregularly shaped ice that has calved from a transition zone between the slow moving Eastern Shelf and the fast moving Tongue.  It tends to stay trapped between the shelf and the tongue before reaching open water after 5-10 years.

Tongue:  Ice that calves from the fasting moving part of Thwaites Glacier, often called the Main Trunk, and tends to stay in formation until it passes over the submerged offshore ridge.  The trunk and the tongue move at about 5 km/year.  The ice tends to calve in long transverse pieces about 10 km long and 1 km wide, which then breakup into roughly 1km squares and get glued to each other with sea ice over many winters before finally breaking up.

Western Calving Front:  This used to be a slower moving part of the Tongue, but now the calving ice tends to float free although it doesn't always move away quickly.  There is usually a lot of ice just offshore combined with ice from the neighboring Haynes Glacier and the Crosson Ice Shelf fed by the Pope and Smith Glaciers.  The Western Calving Front is very close to the Thwaites grounding line in this sector, about a km at points.  The worst case scenario for Thwaites would be if the entire front were to degrade into a calving front like this sector, just dumping icebergs out near the grounding line and providing no buttressing to the glacier.

22
Policy and solutions / Re: Oil and Gas Issues
« on: October 09, 2019, 05:00:33 PM »
The Guardian reports on a major study into oil and gas companies' CO2 emissions since 1965.
35percent emitted by 20 companies and their products.
https://www.theguardian.com/environment/2019/oct/09/revealed-20-firms-third-carbon-emissions

And they knew about climate damage by CO2 from c. 1960-1965.

23
Arctic sea ice / Re: The caa-greenland mega crack
« on: October 09, 2019, 01:06:57 PM »
Today's worldview viirs brightness temperature, band15, night with yesterday's amsr2-uhh inset.
https://go.nasa.gov/2MvVvvg
click for full resolution

24
Policy and solutions / Re: Oil and Gas Issues
« on: October 09, 2019, 03:19:07 AM »
'There Is Not a Climate Crisis': Trump Administration Spouts Brazen Bullshit to Justify Arctic Drilling
Quote
...attorneys with the Sierra Club stumbled upon this tidbit:

“The BLM does not agree that the proposed development is inconsistent with maintaining a livable planet (i.e., there is not a climate crisis). The planet was much warmer within the past 1,000 years, prior to the Little Ice Age, based on extensive archaeological evidence (such as farming in Greenland and vineyards in England). This warmth did not make the planet unlivable; rather, it was a time when societies prospered.”

This text was included five times in this section of the final environmental impact statement in response to public comments legal group Trustees for Alaska submitted. All the All group’s comments revolved around the role drilling in the Alaskan refuge could have in making climate change worse.

This is the first time that the Sierra Club and its partners have identified the use of such blatant climate-denying language in an official federal environmental analysis. Government officials, including Environmental Protection Agency Administrator Andrew Wheeler and even President Donald Trump, have said such things before, but an environmental impact statement is more than words. It’s the legal support for a project. ...
https://earther.gizmodo.com/there-is-not-a-climate-crisis-trump-administration-spo-1838444325/

25
Arctic sea ice / Re: Latest PIOMAS update (October 2019)
« on: October 06, 2019, 10:38:20 AM »
Finally a linear trend. The 2019 data point lies near perfect on the trend line. That means that the zero ice extrapolation has not shifted either and stays at 2032. That, and the fact that is has not changed much for many years gives some confidence to this date.

So for comparison I have added the same graph that I posted in 2012: also a 2032 zero ice extrapolation. The 'prediction' for 2019 is spot-on.

26
Arctic sea ice / Re: Latest PIOMAS update (October 2019)
« on: October 06, 2019, 10:29:10 AM »
Same as the previous but now a Gompertz regression, preferred by some. The Gompertz function approaches but never reaches zero, but still the same postponement to later and later dates is clear.

27
Arctic sea ice / Re: Latest PIOMAS update (October 2019)
« on: October 06, 2019, 10:24:20 AM »
Continuing discussion this, here is an attempt to show how the estimates of zero ice have been shifting. It is the same graph as in the previous post with extrapolations form former years added.
Here the dark blue line is the extrapolation using data up to 2018; The next greenish line data up to 2017
And so fort.
Many years the zero ice prediction was close to 2015 but that has been postponed, on average 1 year every year for the last 6 years or so.
 

29
The rest / Re: The Koch Watch Thread
« on: September 28, 2019, 10:09:04 PM »

30
Antarctica / Re: Thwaites Glacier Discussion
« on: September 27, 2019, 06:10:19 AM »
Here's a final image scaled down by a factor of 8.  A tiny portion of B22-A can be seen at the bottom edge of the image.  The movement of sea ice over a vast region, along with isolated icebergs, iceberg formations, and a huge iceberg almost the size of Rhode Island cannot be a mere coincidence.

Ocean currents and/or wind had to have been the moving force, but the shifting position of B22-A must have allowed the sea ice behind it to follow along bringing smaller icebergs and formations with it.

It also raises the question of whether the fate of Thwaites Ice Tongue can be tied to Iceberg B22-A.  If B22-A were to ever unground and drift off, would the ice tongue become even more vulnerable?

31
Antarctica / Re: Thwaites Glacier Discussion
« on: September 26, 2019, 04:27:59 PM »
Iceberg B22-A has shifted between September 22 and 26.  It is 44 by 24 nautical miles in size and broke off from Thwaites Ice Tongue in 2002 and drifted about 50 km to where it is grounded today.

What's interesting is that is seems to have caused the end of Thwaites Ice Tongue, about one quarter of its length, to separate slightly from the rest.

B22-A shifted in July 2018 and caused the calving of Iceberg B-45 from the nearby Crosson Ice Shelf. https://www.natice.noaa.gov/doc/PR%20-%2020180730%20-%20B-45%20Discovery.pdf

What's puzzling is the mechanism that could cause an effect on the Tongue 50 km away.  The sea between the Tongue and B22-A is covered with sea ice at this time of year so it is possible that the shifting sea ice eased pressure that was holding back the Tongue.  Although it doesn't seem likely, the appearance is that the Tongue was pulled by the sea ice because the remaining 75% of the Tongue did not move as much as the 25% at the end did.  In other words, it looks as if it was pulled away.

Below are links to full resolution images, six days apart.  A small part of B22-A is seen at the bottom edge of the frame.  Please Note that PolarView only hosts these images for 30 days.

https://www.polarview.aq/images/105_S1jpgfull/S1A_IW_GRDH_1SSH_20190926T043625_648C_S_1.final.jpg

https://www.polarview.aq/images/105_S1jpgfull/S1B_IW_GRDH_1SSH_20190920T043542_1AC1_S_1.final.jpg

32
Antarctica / Re: What's new in Antarctica ?
« on: September 20, 2019, 06:43:30 PM »
Surface Melting Causes Antarctic Glaciers to Slip Faster Towards the Ocean, New Research Shows
https://phys.org/news/2019-09-surface-antarctic-glaciers-faster-ocean.html

Surface meltwater draining through the ice and beneath Antarctic glaciers is causing sudden and rapid accelerations in their flow towards the sea, according to new research

Using imagery and data from satellites alongside regional climate modeling, scientists at the University of Sheffield have found that meltwater is causing some glaciers to move at speeds 100 percent faster than average (up to 400m per year) for a period of several days multiple times per year.

The new research, published today in Nature Communications, shows that accelerations in Antarctic Peninsula glaciers' movements coincide with spikes in snowmelt. This association occurs because surface meltwater penetrates to the ice bed and lubricates glacier flow.

The effects of such a major shift in Antarctic glacier melt on ice flow has not yet been incorporated into the models used to predict the future mass balance of the Antarctic Ice Sheet and its contribution to sea level rise.



Open Access: Peter A. Tuckett et al. Rapid accelerations of Antarctic Peninsula outlet glaciers driven by surface melt, Nature Communications (2019)

33
Arctic sea ice / Re: The 2019 melting season
« on: September 18, 2019, 01:46:22 AM »
I've discovered that Peter Wadhams has just made a new preprint available via ResearchGate on my favourite, and his specialist, subject - Waves in ice!

https://www.researchgate.net/publication/334223747_Wave-ice_interaction_in_the_North-West_Barents_Sea

Quote
The field work was performed in the Barents Sea, and the main focus of the paper is on wave processes in the MIZ. A model of wave damping in broken ice is formulated and applied to interpret the field work results. It is confirmed that waves of higher frequencies are subjected to stronger damping when they propagate below the ice. This reduces the frequency of most energetic wave with increasing distance from the ice edge. Difference of wave spectra measured in two relatively close locations within the MIZ is discussed. The complicated geometry and dynamics of the MIZ in the North-West Barents Sea allow waves from the Atlantic Ocean and south regions of the Barents Sea to penetrate into different locations of the MIZ.

34
Arctic sea ice / Re: The 2019 melting season
« on: September 16, 2019, 11:50:44 PM »
Over on the ASIB, I've just posted the late(st) PIOMAS update, and I just wanted to share the final half here, because it's how I view this melting season. Normally, I don't like it when people post long texts, but I'm the exception to that rule, of course.  ;)

Quote
Last month, I wrote at the end of the PIOMAS update:

Quote
From what I've seen on the Arctic Sea Ice Forum, written by commenters I've known for years and highly respect, my gut feeling says this year won't be able to break the 2012 records.

But for weeks now, I've been thinking of those prophetic words uttered by Peter Wadhams, back in 2007: 'In the end, it will just melt away quite suddenly.' I don't think all of it will melt away quite suddenly in coming weeks, but maybe more than one would expect just looking at the data.

This year is a great test that will tell us a lot about the importance of melting momentum.

To be honest, I expected a clearer melting momentum signal during this final phase of the melting season. Melting momentum took off slower than years like 2012 and 2016, but when it did take off, it was fireworks (see June 2019, one hell of a month). David Schröder's melt pond fraction maps, the SMOS pixel chart, the compactness charts, the Albedo-Warming Potential graphs, the snow cover graphs, more and more they were pointing to a massive build-up of melting momentum. On top of that, PIOMAS was showing that this year was very competitive volume-wise, and for five months in a row, 2019 was in the top 3 when it came to temperature records (August coming in lowest on record):



It was clear that the spell of extremely sunny, warm weather was ending during August. That, to me, was the great test for my melting momentum theory. Weather conditions switched, but for a week or so extent loss was keeping up with 2012's pace, despite the boost provided by the GAC. But then halfway through the month, things slowed down to a crawl after all (see red trend line):



So, what happened? Of course, there was a cyclone that was in a perfect position to disperse the ice, but there was so much weak ice that in my view, momentum should have gone on for a while longer.

There are two possibilities:

1) There wasn't as much melting momentum as I assumed.

2) Melting momentum is less important than I think it is.

As said, it took a while for melting momentum to get going. Timing is of the essence when it comes to breaking melting season records. May was actually very sunny this year, but most of the radiation coming from a Sun at a still low angle, got bounced off the pristine white ice. It may sound counterintuitive, but before the real melt ponding gets going due to open skies, cloudy weather is actually worse for the ice, because with clouds comes humidity and the clouds also block outgoing radiation. This can cause the snow on top of the ice to melt just a tiny bit, deforming the structure of the snow, making it more prone to melt when the sun starts to shine in earnest. 2019 came short in this respect, as evidenced by visual inspection of satellite images. Never mind the fact that the 2018/2019 freezing season was much less spectacular compared to the previous three winters, when it comes to temperatures and extreme weather conditions.

I'm still convinced that without a decent amount of melting momentum no records will be broken. That's why in years like 2016, 2017 and 2018 it was possible to announce at an early date that the 2012 record was safe. But conversely, a massive amount of melting momentum doesn't guarantee records either. Initial ice conditions and late stage weather obviously play important roles as well.

Maybe I'm emphasizing melting momentum too much, but I still feel kind of vindicated by recent developments on the extent front. Over the last week, just a small amount of weather conducive to melting has helped nudge 2019 below the 2007 and 2016 minimums, with quite an impressive run of daily drops. Tomorrow or the day after, the 4 million km2 mark could even be breached. I always thought that this year would come in second whatever would happen, and it looks like it has:



Either way, after almost 10 years of blogging, I'm now clearly seeing the contours of that first year when ice-free conditions will be reached (in other words, an ice cover smaller than 1 million km2, which amounts to ice-free for all practical purposes). It is preceded by a freezing season similar to that of 2015/2016, starts with the melt onset 2012 saw, builds up the massive melting momentum of 2019, and ends with the crazy weather of 2016. It makes me shudder to think what the satellite images will look like then. It may take more time than most cryospheric scientists think it will take, but unfortunately, that's not much of a comfort.

The ingredients are there, AGW is the cook.

35
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: September 12, 2019, 06:00:43 AM »
September 11th, 2019:
     4,110,564 km2, a drop of -39,332 km2.
     2019 is now 2nd lowest on record.
     (2007, 2012 & 2016 highlighted).

Thanks Juan, always appreciated.


The forecast winds are so favourable for compaction of the ice pack that extent may well drop all the way below 4 million km2 over the course of the next several days, and before freeze-up finally takes hold.

That is so even though 4 million km2 has at times been below the predicted range obtained from extrapolating using the progressions to the minima from the previous years on record -- see the plots that gerontocrat has been posting. (After today's drop though, 4 million km2 is presumably back within the range from those projections.)


The significance of that, of course, is that 2019 would become only the second year to drop below the 4 million km2 marker and it would reach the second lowest minimum extent in the record, below all years except 2012 (all the way down at 3.18 million km2).

36
Consequences / Re: Hurricane Season 2019
« on: September 09, 2019, 02:28:41 AM »
Dorian One of Strongest, Longest-Lasting Hurricanes on Record in the Atlantic
Quote
Dorian was also among the longest-lasting named storms, Klotzbach said.
As of Friday evening, it had been a named storm for more than 13 days, nine of them as a hurricane.

"It's quite unusual for a hurricane to remain a hurricane for as many days as Dorian has," said climate scientist Michael Mann....
...
Dorian May Have Influenced the Gulf Stream
It also looks like Dorian may also have influenced the Gulf Stream, the strong ocean current that brings warm water from the Gulf of Mexico into the Atlantic Ocean, possibly contributing to localized coastal flooding.

An undersea monitor near Miami indicated that Dorian might have slowed the speed of that current, with powerful winds pushing against it, along with a disruptive underwater churn. A slower Gulf Stream can cause the surface of the ocean to rise by several inches to a foot or more, said Tal Ezer, an oceanographer at Old Dominion University in Norfolk, Va.

That would underlie any storm surge, he said, and the effect can linger for days as it did in 2016 in Norfolk with extended sunny weather flooding the aftermath of Hurricane Matthew, whose path was similar to Dorian's. He said he's looking for that to happen in the coming days.

"After the hurricane disappears, streets remained flooded," he said. "The drainage system was blocked and couldn't drain the rain."
https://insideclimatenews.org/news/07092019/hurricane-dorian-record-climate-change-bahamas-north-carolina-gulf-stream

37
Arctic sea ice / Re: Home brew AMSR2 extent & area calculation
« on: September 04, 2019, 09:07:31 AM »
A late century drop in extent shows there are still possibilities for second lowest place ( in my limited data set).

Here is an animation of the Arctic Basin compared with 2012. Click to start.

38
Arctic sea ice / Re: Latest PIOMAS update (September 2019)
« on: September 04, 2019, 08:42:20 AM »
The volume and volume-anomaly graphs.

39
Arctic sea ice / Re: Latest PIOMAS update (September 2019)
« on: September 04, 2019, 08:28:36 AM »
PIOMAS gridded thickness data has updated (official volume data not yet). Volume on 31st August was 4.17 [1000km3], second lowest behind 2012 (3.93[1000km3]).

Here is the animation for August.

40
Consequences / Re: Hurricane Season 2019
« on: September 04, 2019, 03:54:24 AM »
Thread by @iCyclone:
Quote
Yep, I’m alive. Made it to Nassau. #Hurricane #DORIAN: By far the most intense cyclone I’ve witnessed in 28 years of chasing. Thought I was playing it safe by riding it out in a solid-concrete school on a hill in Marsh Harbour. Thought wrong. ...
https://threadreaderapp.com/thread/1169009558167142402.html

41
Arctic sea ice / Re: The 2019 melting season
« on: September 03, 2019, 07:00:11 AM »
I'm not sure if things will get ugly as the low will be a cold one
Hi Paul. Your second name isn't Beckwith by any chance? That would be an honor! :)
When you say "this is a cold one", are you talking about the resident CAB low, or the new one that came off Norway, and joined the resident low? Looking at these images, you can see how it's sucking in warm moist air from Russia. This air is the engine for that low. no? The more heat it sucks in, the stronger it gets?

I need to continue watching this lecture and learn some more, but I haven't had the time yet...
Anyone familiar with this lecture?

Edit: Already on Lecture 6 now: Introduction to convective storms. This is really interesting! He explains everything clearly in detail, from the ground up. Perfect for someone like me, with only basic knowledge about the "weather".

42
Consequences / Re: Hurricane Season 2019
« on: September 02, 2019, 10:44:21 PM »
https://mobile.twitter.com/Bahamaspress

Video: https://mobile.twitter.com/Bahamaspress/status/1168599030261325825

... Residents climbed into their roof as floodwaters wash away homes and cars in Freeport, Grand Bahama.

... Churchill Drive in Freeport is now under water. Residents are seeking assistance.

... A growing wall of missing persons is being published by BP as families in Abaco become frantic on the location of their loveones. Communities in Abaco are under water and many are missing and feared dead

-----------------------

Video shows rows of power trucks assembling in Wildwood, Florida
https://www.cnn.com/us/live-news/hurricane-dorian-september-2019/index.html

-----------------------

Quote from: RikW
... I think these predictions get updated automatically and if I understanding correctly most of them predict Dorian to reach Nova Scotia in 5/6 days while still being near a cat1/ cat2 hurricane?

That is rare, isn’t it?

Rare but not unheard of ...

NOAA Historic Hurricane Tracker
https://oceanservice.noaa.gov/news/historical-hurricanes/
https://coast.noaa.gov/hurricanes/


Shown here: Category 4 and 5 hurricane tracks from 1851-2016 in the East Atlantic ocean basin.

43
Policy and solutions / Re: Greta Thunberg's Atlantic crossing
« on: September 02, 2019, 02:22:21 AM »
Why do you keep attacking the messenger?

For someone who thinks they are a well read layperson concerning Aspergers, you really dont know much about it at all.

Let me educate you somewhat because you seem to need it.

1 - she is almost certainly disliking sitting around so many people. Why? Because several of her senses will probably be overstimulated and the most effective way to cope is to attempt to ignore them. Not easily done.

2 - as mentioned elsewhere, her diagnosis, or part of it, named one aspect where she only speaks when there is a need to speak, or when she feels like she has something to say. Personally, I am the same and in that situation in the photo, I would be doing exactly the same thing. Bored, overstimulated and having nothing to add to anything because it is already being said or I have already said it.

Also, one image says bugger all. Look at the people around her with the same look on their face? I bet most are neuro typicals, are you going to give a critical analysis on them as well?

And she is on script.
She speaks her mind.
She is consistent.
She quotes the science.

3 - Asperger's people have another quality that is lacking in neurotypical people.... it is called hyper focus. If anything, she will double down on this, not disappear. She will not stop, ever, until she feels she has resolved her own criteria for action being taken.
Trust me on this one, she is hyper focused on this. She will not simply disappear.

And stop talking about the people around her as being her handler. She is not a dog or a pet. She is a teenage woman who needs support just like any other human being. Seriously, just how much more insulting could you become?

44
Arctic sea ice / Re: The 2019 melting season
« on: August 28, 2019, 04:56:16 AM »
Nice. Didn't realise you could drag the base layers and have semi transparent modis over bathy.
https://go.nasa.gov/345rHxN
No gifs with transparency though
Yesterday I compared 2012 ice cover with this year on the same date. This tool makes it easy to compare both years, and I don't see any way how we could catch up to 2012 without an apocalyptic storm.

2012 vs 2019
https://go.nasa.gov/2PeCF0m

45
I have trouble uploading data and graphs to the 'arctischepinguin' google site. So the updates will be delayed until the google errors are resolved or I have found time to do it manually.

46
The volume and volume-anomaly graphs.

47
Here is the animation for August until now.

48
Arctic sea ice / Re: The 2019 melting season
« on: August 21, 2019, 07:36:07 AM »
The storm has shifted a little towards Ellesmere island, which seems to have taken the sharp edge of this storm. Strong winds over M'Clure Strait have diminished significantly, making it doubtful that the channels will be cleared. The biggest problem I see now is the huge wind field, which will probably cause a lot of dispersion. And it looks like the cyclone that came off Norway is strengthening. Feeding off the CAA storm?

Reminder; This is all new for me! I'm a complete amateur who's still learning. So always take my analysis with a big bag of salt! Making these videos will surely help me to learn more quickly. Enjoy!

50
Arctic sea ice / Re: The 2019 melting season
« on: August 19, 2019, 03:00:36 AM »
Big dent in the Laptev ice.

https://go.nasa.gov/2P3MeiN

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