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nanning

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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2550 on: January 10, 2020, 07:09:34 PM »
"850-300mm" should read "850-300mbar".

I looked up radiosonde.

A radiosonde is a battery-powered telemetry instrument carried into the atmosphere usually by a weather balloon that measures various atmospheric parameters and transmits them by radio to a ground receiver. Modern radiosondes measure or calculate the following variables: altitude, pressure, temperature, relative humidity, wind (both wind speed and wind direction), cosmic ray readings at high altitude and geographical position (latitude/longitude).
"It is preoccupation with possessions, more than anything else, that prevents us from living freely and nobly" - Bertrand Russell
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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2551 on: January 10, 2020, 08:40:59 PM »
"850-300mm" should read "850-300mbar".

I looked up radiosonde.

A radiosonde is a battery-powered telemetry instrument carried into the atmosphere usually by a weather balloon that measures various atmospheric parameters and transmits them by radio to a ground receiver. Modern radiosondes measure or calculate the following variables: altitude, pressure, temperature, relative humidity, wind (both wind speed and wind direction), cosmic ray readings at high altitude and geographical position (latitude/longitude).

Thanks.  I have corrected the original post.
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AbruptSLR

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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2552 on: January 10, 2020, 09:22:50 PM »
the conversion of the GISS baseline of 1951-1980 to pre-industrial is +0.23C


My notes say that the GISTEMP (LOTI = Land Ocean Temperature Index) 1951-1980 baseline to preindustrial baseline adjustment factor is +0.256C.
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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2553 on: January 10, 2020, 09:39:19 PM »
Per the attached plot from: "5-day forecast of the 2019-2020 Antarctica ice sheet SMB simulated by MARv3.10 forced by GFS", the ASE area is experiencing an extended surface ice melt season:

http://climato.be/cms/index.php?climato=the-2020-melt-season-over-antarctica-as-simulated-by-marv3-10
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Sciguy

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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2554 on: January 10, 2020, 10:52:05 PM »
"850-300mm" should read "850-300mbar".

I looked up radiosonde.

A radiosonde is a battery-powered telemetry instrument carried into the atmosphere usually by a weather balloon that measures various atmospheric parameters and transmits them by radio to a ground receiver. Modern radiosondes measure or calculate the following variables: altitude, pressure, temperature, relative humidity, wind (both wind speed and wind direction), cosmic ray readings at high altitude and geographical position (latitude/longitude).

Thanks.  I have corrected the original post.

The IPCC special report on 1.5C published in 2018 stated,

Quote
Human-induced warming reached approximately 1°C (likely between 0.8°C and 1.2°C) above pre-industrial levels in 2017, increasing at 0.2°C (likely between 0.1°C and 0.3°C) per decade (high confidence). Global warming is defined in this report as an increase in combined surface air and sea surface temperatures averaged over the globe and over a 30-year period. Unless otherwise specified, warming is expressed relative to the period 1850–1900, used as an approximation of pre-industrial temperatures in AR5. For periods shorter than 30 years, warming refers to the estimated average temperature over the 30 years centred on that shorter period, accounting for the impact of any temperature fluctuations or trend within those 30 years. Accordingly, warming from pre- industrial levels to the decade 2006–2015 is assessed to be 0.87°C (likely between 0.75°C and 0.99°C). Since 2000, the estimated level of human-induced warming has been equal to the level of observed warming with a likely range of ±20% accounting for uncertainty due to contributions from solar and volcanic activity over the historical period (high confidence). {1.2.1}

https://www.ipcc.ch/sr15/chapter/chapter-1/

The GISS LOTI in 2017 was 0.91.  So the difference between the LOTI and pre-industrial is +0.09C.  Which rounds to 0.1 if using one significant digit.

Note that the previous reference I used stated that 2015 was the year that the temperature was 1 degree over pre-industrial.  In 2015, the LOTI was 0.87.  The difference between LOTI and pre-industrial as defined in that reference would be 0.13C.  Which rounds to 0.1 if using significant digit.

2016 was much warmer than 2015 and 2017 at a LOTI of 1.04.  It was also an El Nino year.  To reduce the impact of the ENSO on annual temperature variations, it's customary to use a 5 year average to show the current temperature.

From NASS GISS's webpage here: https://data.giss.nasa.gov/gistemp/tabledata_v4/GLB.Ts+dSST.txt

the past 5 years of LOTI are:

2019  0.97
2018  0.85
2017  0.91
2016  1.04
2015  0.87

The five-year average would be: 0.928 which would round to 0.9 using one significant digit.

So we are approximately 1 degree C over pre-industrial temperatures now.


Hefaistos

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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2555 on: January 10, 2020, 11:11:20 PM »
This Caldwell paper is a very good find.

Based on my reading of earlier work from his team, I can see now why E3SM has the highest ECS and TCR since they have been on the cutting edge of tropical cloud constraints.   Looks like they also have better sea ice modeling.  It is a little surprising that the higher resolution didn't increase sensitivity.

Yes, the Caldwell paper gives good insights into these very advanced GCM modelling efforts.

As we have discussed ECS values here in this thread, it's interesting to note that: "Since we cannot afford to run the fully coupled HR /High Resolution/ model for the hundreds of years necessary to compute transient or equilibrium climate sensitivity,..." (quote from section 6),
and they resort to calculate the lambda coefficient instead. It allows one to compute the effective net feedback from the change in TOA radiative imbalance ΔFTOA caused by forcing global‐average surface temperature Tglob, ave to change as a constant lambda. Well, at least it's assumed to be a constant in the short run, whereas no one knows how it behaves in the long run. What they find is that "The direct effect of increasing resolution causes a slight strengthening of λ, indicating stronger resistance to temperature change and therefore weaker climate sensitivity". The more true HR model has a lower ECS than the LR one, (the latter one is used for CMIP6).

These models are incredibly complex, always run on supercomputers, and the High Resolution version is so computationally demanding that they cannot afford to run essential tests for tuning, and a run to extract ECS from the model is also "unaffordable".

The LR version of E3SM displays a rather suspicious behaviour when it comes to GSTs, as demonstrated in the attached figure. Looks like it's rigged to run cool until 1995 or so, and then it's set off on a very steep trajectory. Surely, this indicates high ECS and TCR values, but should we trust them when model behavior is so apparently wrong?

If you read the Caldwell paper you also understand that the LR version is substandard, as the HR version "is sufficient to capture the most energetic motions in the ocean, which are poorly represented in standard resolution coupled climate models."

This is perhaps the most essential aspect of GCMs: they are unable to model the most energy intense climate processes, i.e. the hydrological cycle and esp. deep convection in the tropics. From this point of view, the HR version reported in the Caldwell paper is a step forward, and it's a deep pity that model complexity makes it rather unusable due to computational costs.

See my Reply #1668 above.
« Last Edit: January 10, 2020, 11:28:19 PM by Hefaistos »

wdmn

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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2556 on: January 10, 2020, 11:16:32 PM »
@KenFeldman

With all due respect what are you trying to pull? Multiple sources have already shown that following the IPCC conventions 2019 comes in at 1.2C above preindustrial. Or are you saying that ECMWF is wrong?

https://climate.copernicus.eu/surface-air-temperature-december-2019

"Averaging over twelve-month periods smooths out the shorter-term variations. Globally, the calendar year 2019 was 0.59°C warmer than the 1981-2010 average. The warmest twelve-month period was from October 2015 to September 2016, with a temperature 0.66°C above average. 2016 is the warmest calendar year on record, with a global temperature 0.63°C above that for 1981-2010. 2019 has become the second warmest calendar year in this data record. The third warmest calendar year, 2017, had a temperature 0.54°C above average.

0.63°C (±0.06ºC) should be added to these values to relate recent global temperatures to the pre-industrial level defined in the IPCC Special Report on “Global Warming of 1.5°C”. Using the central estimate and rounding to one decimal place, the average temperature for 2019 is 1.2°C above the level."

Moreover, the GISTEMP LOTI graphs are available from people like Gavin Schmidt of NASA, and clearly indicate we are above 1C of warming, as the below pic (published in December 2019) demonstrates.

Please stop gaslighting.

Sciguy

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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2557 on: January 10, 2020, 11:55:42 PM »
@KenFeldman

With all due respect what are you trying to pull? Multiple sources have already shown that following the IPCC conventions 2019 comes in at 1.2C above preindustrial. Or are you saying that ECMWF is wrong?

https://climate.copernicus.eu/surface-air-temperature-december-2019

"Averaging over twelve-month periods smooths out the shorter-term variations. Globally, the calendar year 2019 was 0.59°C warmer than the 1981-2010 average. The warmest twelve-month period was from October 2015 to September 2016, with a temperature 0.66°C above average. 2016 is the warmest calendar year on record, with a global temperature 0.63°C above that for 1981-2010. 2019 has become the second warmest calendar year in this data record. The third warmest calendar year, 2017, had a temperature 0.54°C above average.

0.63°C (±0.06ºC) should be added to these values to relate recent global temperatures to the pre-industrial level defined in the IPCC Special Report on “Global Warming of 1.5°C”. Using the central estimate and rounding to one decimal place, the average temperature for 2019 is 1.2°C above the level."

Moreover, the GISTEMP LOTI graphs are available from people like Gavin Schmidt of NASA, and clearly indicate we are above 1C of warming, as the below pic (published in December 2019) demonstrates.

Please stop gaslighting.

I'm reporting what the IPCC says.  Here it is right from the Executive Summary of the Special Report Global Warming of 1.5C published in 2018.

https://www.ipcc.ch/sr15/chapter/spm/

Quote
A.1. Human activities are estimated to have caused approximately 1.0°C of global warming  above pre-industrial levels, with a likely range of 0.8°C to 1.2°C. Global warming is likely to reach 1.5°C between 2030 and 2052 if it continues to increase at the current rate. (high confidence) (Figure SPM.1) {1.2}

A.1.1. Reflecting the long-term warming trend since pre-industrial times, observed global mean surface temperature (GMST) for the decade 2006–2015 was 0.87°C (likely between 0.75°C and 0.99°C) higher than the average over the 1850–1900 period (very high confidence). Estimated anthropogenic global warming matches the level of observed warming to within ±20% (likely range). Estimated anthropogenic global warming is currently increasing at 0.2°C (likely between 0.1°C and 0.3°C) per decade due to past and ongoing emissions (high confidence). {1.2.1, Table 1.1, 1.2.4}

I'd note that your estimate of 1.2C above pre-industrial levels is within the 95% confidence interval range.  1 C is the most likely result.  Note that since "pre-industrial" isn't precisely defined anywhere, there is a range of baselines that people use as "pre-industrial".

Don't accuse people of gas-lighting just because you disagree with them. Look at the evidence they use to support their arguments.


jai mitchell

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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2558 on: January 11, 2020, 01:18:44 AM »
Nearly every aspect of the SR1.5 was adjusted in the conservative direction to provide the largest possible carbon budge as possible.  Including reduced ECS/TCR, no inclusion of frozen soil feedbacks, severely understated carbon cycle feedbacks (only 100 GtCO2 by 2100!) and an inappropriate baseline that is higher than the actual (per Michael E. Mann).

more info here:  https://www.scientificamerican.com/article/new-climate-report-was-too-cautious-some-scientists-say/
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Telihod

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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2559 on: January 11, 2020, 09:34:41 AM »

I'd note that your estimate of 1.2C above pre-industrial levels is within the 95% confidence interval range.  1 C is the most likely result.  Note that since "pre-industrial" isn't precisely defined anywhere, there is a range of baselines that people use as "pre-industrial".

Don't accuse people of gas-lighting just because you disagree with them. Look at the evidence they use to support their arguments.

It's not his estimate. If you click on his link and scroll down, then you can see that he is quoting from  the copernicus european scientists.

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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2560 on: January 11, 2020, 10:45:55 AM »
Hefeistos:
Hopefully the coming exascale supercomputers will be able to afford the better models.

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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2561 on: January 11, 2020, 03:59:45 PM »
While I do not like to dwell on this topic, the linked article makes it clear that climate change denial is both organized and relatively successful at blunting action to effectively address climate change(see the two associated image); including by distracting consensus climate science; which of course, increases the likelihood that serious climate consequences will occur this century:

Title: "Climate Change Denial Explained", 2018

https://skepticalscience.com/agw-denial-explained.html

&

Title: "Climate Change Denial Explained: Tactics of Denial", 2018

https://skepticalscience.com/agw-denial-explained-2.html
« Last Edit: January 11, 2020, 04:08:38 PM by AbruptSLR »
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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2562 on: January 11, 2020, 05:32:25 PM »

I'd note that your estimate of 1.2C above pre-industrial levels is within the 95% confidence interval range.  1 C is the most likely result.  Note that since "pre-industrial" isn't precisely defined anywhere, there is a range of baselines that people use as "pre-industrial".

Don't accuse people of gas-lighting just because you disagree with them. Look at the evidence they use to support their arguments.



It's not his estimate. If you click on his link and scroll down, then you can see that he is quoting from  the copernicus european scientists.

Since anthropogenic CO2 emissions are the culprit, why not just look at the consumption of fossil fuels instead of arguing about when the industrial revolution started.
« Last Edit: January 11, 2020, 05:54:22 PM by Shared Humanity »

AbruptSLR

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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2563 on: January 11, 2020, 05:51:49 PM »

I could pull-up images from many prior posts to show that effective ECS and its impacts on GMSTA could be increasing already, but that consensus climate scientists fail to make such attributions.


It is my opinion that one major reason that consensus climate science exposes modern society to major unacknowledged climate change risks is because it emphasizes the use of either deductive or inductive reasoning, at the expense of abductive reasoning.  Thus, I believe that climate science could learn a lot from the use of abductive learning in AI programs as discussed in the linked video and associated linked reference; in order to improve their attribution of feedback mechanisms such as ice-climate feedbacks within their ESM runs.

Title: "Wang-Zhou Dai: Bridging Machine Learning and Logical Reasoning by Abductive Learning"



Extract: "Perception and reasoning are two representative abilities of intelligence that are integrated seamlessly during problem-solving processes. In the area of artificial intelligence (AI), perception is usually realised by machine learning and reasoning is often formalised by logic programming. However, the two categories of techniques were developed separately throughout most of the history of AI. This talk will introduce the abductive learning framework targeted at unifying the two AI paradigms in a mutually beneficial way. In this framework, machine learning models learn to perceive primitive logical facts from the raw data, while logical reasoning is able to correct the wrongly perceived facts for improving the machine learning models. We demonstrate that by using the abductive learning framework, computers can learn to recognise numbers and resolve equations with unknown arithmetic operations simultaneously from images of simple hand-written equations. Moreover, the learned models can be generalized to complex equations and adapted to different tasks, which is beyond the capability of state-of-the-art deep learning models."

See also:

Title: "Bridging Machine Learning and Logical Reasoning by Abductive Learning", 2019

https://papers.nips.cc/paper/8548-bridging-machine-learning-and-logical-reasoning-by-abductive-learning

As background on this matter, generally speaking, there are three types of reasoning: deductive, inductive and abductive.  Unlike induction or deduction, where science starts with cases to make conclusions about a rule, or vice versa, with abduction, scientists generate a hypothesis to explain the relationship between a case and a rule. Also, abduction assumes there is insufficient evidence to deduce any single explanation or cause. More concisely, in abductive reasoning, scientists make an educated guess, and illustrated by the following quote from Josephson & Josephson:

"Abduction, of inference to the best explanation, is a form of inference that goes from data describing something to a hypothesis that best explains or accounts for the data.
D is a collection of data (facts, observations, givens).
H explains D (would, if true, explain D).
No other hypothesis can explain D as well as H does.
... Therefore, H is probably true."

– Josephson & Josephson, Abductive Inference"

Part of what makes the application of abductive reasoning challenging is that scientists have to infer some likely hypotheses from a truly infinite set of explanations. The reason that this is significant is because when scientists are faced with complex problems, part of the way that humans solve them is by tinkering. Human typically play, trying several approaches, keeping one's value system fluid as we search for potential solutions. Specifically, we generate hypotheses. Where a computer might be stuck in an endless loop, iterating over infinite explanations, we use our value systems to quickly infer which explanations are both valid and likely.

Finally, conventional AI computers/machines face considerable difficulty in deciding what data is really information; which is also a problem that consensus climate scientists face when trying to attribute cause to the various mechanisms modeled within their ESM runs.
« Last Edit: January 11, 2020, 06:12:46 PM by AbruptSLR »
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AbruptSLR

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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2564 on: January 11, 2020, 06:00:20 PM »
As Europeans, Asians and African increasing adopt current US life-styles (such as increasing use of SUVs as cited in the linked article) it will be increasingly difficult to avoid climate catastrophes in the coming decades:

Title: "Booming sales of SUV cars could offset the benefits from electric cars, the International Energy Agency has warned"

http://news.trust.org/item/20200110105210-xhazm/

Extract: "Soaring demand for SUVs drove record sales for premium carmakers including BMW and Mercedes last year, leaving the industry on collision course with government efforts to tackle global warming despite big investments in electric vehicles."
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
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nanning

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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2565 on: January 11, 2020, 08:01:44 PM »
^^
Africans wanting to adopt U.S. life styles because of T.V. was in the early 80's called the "Dallas effect" here (NL), after the series "Dallas".
Temptation -> want -> more want etc.
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Why do you keep accumulating stuff?

jai mitchell

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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2566 on: January 11, 2020, 08:32:16 PM »
the conversion of the GISS baseline of 1951-1980 to pre-industrial is +0.23C


My notes say that the GISTEMP (LOTI = Land Ocean Temperature Index) 1951-1980 baseline to preindustrial baseline adjustment factor is +0.256C.

I stand corrected, I have been looking for the value from the peer review but can't find it (I thought it was a 2012 hansen sato paper. . .)
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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2567 on: January 11, 2020, 09:05:11 PM »
^^
Africans wanting to adopt U.S. life styles because of T.V. was in the early 80's called the "Dallas effect" here (NL), after the series "Dallas".
Temptation -> want -> more want etc.

While living the African Dream may be sometime in the future for most Africans; the linked article confirms that the majority of Chinese are now beginning to live the Chinese version of the American Dream:

Title: "The American Dream Is Alive In China"

https://palladiummag.com/2019/10/11/the-american-dream-is-alive-in-china/

Extract: "When I visited China in the 2000s and early 2010s, there was a general sense that “now is the time to put your head down and work hard to support the economy.” Now, the feeling has become “start learning how to enjoy life and take pride in the results of everyone’s hard work.”"
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nanning

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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2568 on: January 12, 2020, 07:13:43 AM »
^^
(sorry, couldn't resist)

Africans living the "African Dream" is not sometime in the future but way back in the past from before colonisation by civilisation (Romans, western Europe).

From https://en.wikiquote.org/wiki/Desmond_Tutu
In Desmond Tutu: A Biography (2004) by Steven Gish, p. 101; is clarified Tutu used it as a joke which was not of him.

"When the missionaries came to Africa they had the Bible and we had the land. They said "Let us pray." We closed our eyes. When we opened them, we had the Bible and they had the land."


It is clear to me that this perceived "Dream" is destroying all life on Earth.

I read sidd's posts and they give another view on this 'Dream' in the U.S.A..


Apologies for shoehorning my 'alien perspective'.
"It is preoccupation with possessions, more than anything else, that prevents us from living freely and nobly" - Bertrand Russell
"It is preoccupation with what other people from your groups think of you, that prevents you from living freely and nobly" - Nanning
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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2569 on: January 12, 2020, 05:16:15 PM »
We should not forget the risk that refrigerants (whose use is accelerating with increasing: population, per capita and global warming) represent w.r.t. global warming potential; particularly as developing nations may not adequately recycle their growing banks of HFCs:

Title: "Refrigerant Management"

https://www.drawdown.org/solutions/materials/refrigerant-management

Extract: "Every refrigerator and air conditioner contains chemical refrigerants that absorb and release heat to enable chilling. Refrigerants, specifically CFCs and HCFCs, were once culprits in depleting the ozone layer. Thanks to the 1987 Montreal Protocol, they have been phased out. HFCs, the primary replacement, spare the ozone layer, but have 1,000 to 9,000 times greater capacity to warm the atmosphere than carbon dioxide.

Scientists estimate the Kigali accord will reduce global warming by nearly one degree Fahrenheit. Still, the bank of HFCs will grow substantially before all countries halt their use. Because 90 percent of refrigerant emissions happen at end of life, effective disposal of those currently in circulation is essential. After being carefully removed and stored, refrigerants can be purified for reuse or transformed into other chemicals that do not cause warming."
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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2570 on: January 12, 2020, 05:33:03 PM »
Can you detect a trend in the decadal Berkeley Earth GMSTA data (see attached plot) for the last several (four) decades:
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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2571 on: January 12, 2020, 05:53:11 PM »
If I am correct, then the attached image from the Sentinel-1 satellite for January 12, 2020 shows that the seaward end of the Thwaites Ice Tongue has become unpinned and the ice tongue is currently in the process of disintegrating.
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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2572 on: January 12, 2020, 08:43:13 PM »
Review of the first order draft of the IPCC WGIII AR6 document begins tomorrow and will be completed by March 8, 2020.
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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2573 on: January 13, 2020, 05:34:54 PM »
It will be interesting to learn what the robotic submarine Icefin finds out about the subglacial cavity at the grounding line near the base of the Thwaites Ice Tongue:

Title: "Scientists Are Racing to Figure Out Why This Giant Glacier in Antarctica Is Melting So Fast"

https://www.livescience.com/why-giant-antarctic-glacier-melting-so-fast.html

Extract: "A robotic submarine is about to descend into a dark, water-filled cavern in Antarctica, to try to find out why one of the continent's largest glaciers is melting so fast.

In the next few days, scientists will lower the torpedo-shaped robot, dubbed Icefin, into a nearly 2,000-foot-long (600 meters) borehole in the ice of Thwaites Glacier in West Antarctica.

The MELT project scientists flew out to the Thwaites Glacier a few weeks ago and are now camped out on its eastern ice tongue. They have melted and drilled out a 20-inch-wide (50 centimeters) access hole through the ice near its grounding line, Cutler told Live Science in an email.
In the coming days, they will lower the Icefin robot through the ice to explore a vast cavity, two-thirds of the area of Manhattan, which researchers using ice-penetrating radar discovered beneath the glacier last year."

Caption for first image: "The borehole through the ice of the Thwaites Glacier is near the "grounding line," where it leaves the Antarctic bedrock and starts floating on the Amundsen Sea"

Edit:

For ease of reference, I provide the last three attached images showing the location and characteristics of the ice around the subglacial cavity near the base of the Thwaites Ice Tongue.
« Last Edit: January 13, 2020, 05:42:55 PM by AbruptSLR »
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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2574 on: January 13, 2020, 06:04:01 PM »
The fact that '… the world's oceans (especially at upper 2000m) in 2019 were the warmest in recorded human history", supports the concept that slow-response climate feedback mechanisms related to the ocean may well already be contributing to climate sensitivity:

Cheng, L., Abraham, J., Zhu, J. et al. Record-Setting Ocean Warmth Continued in 2019. Adv. Atmos. Sci. 37, 137–142 (2020) doi:10.1007/s00376-020-9283-7

https://link.springer.com/article/10.1007/s00376-020-9283-7
&
https://link.springer.com/content/pdf/10.1007/s00376-020-9283-7.pdf

Extract: "These data reveal that the world's oceans (especially at upper 2000m) in 2019 were the warmest in recorded human history."
« Last Edit: January 14, 2020, 12:30:27 AM by AbruptSLR »
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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2575 on: January 13, 2020, 06:13:19 PM »
The linked article discusses some of the technical details of the TIME study; which is part of the International Thwaites Glacier Collaboration.

Kornei, K. (2020), Controlled explosions pave the way for Thwaites Glacier research, Eos, 101, https://doi.org/10.1029/2020EO138299. Published on 10 January 2020

https://eos.org/articles/controlled-explosions-pave-the-way-for-thwaites-glacier-research

Extract: "Last year, researchers working near the city of Tornillo, Texas, intentionally detonated a series of explosives mounted atop poles. The shock waves created by the detonations sent seismic waves into the ground. This technique, known as “active source seismic,” allows scientists to infer properties of the subsurface based on how those seismic waves propagate.

Later this year, researchers working in Antarctica will use this method to study Thwaites. Thwaites is currently responsible for about 4% of sea level rise worldwide. Some scientists believe that if Thwaites collapsed, the entire West Antarctic Ice Sheet might destabilize and break apart, boosting sea levels by more than a meter.

In November 2019, roughly 100 scientists and support staff departed for Antarctica as part of the International Thwaites Glacier Collaboration. This consortium, funded by the National Science Foundation and the United Kingdom’s Natural Environment Research Council, consists of eight different projects. One of those is Thwaites Interdisciplinary Margin Evolution (TIME), an endeavor to better understand the boundaries (the margins) of the glacier. The size of Thwaites dictates how much ice is flowing into the sea, said Slawek Tulaczyk, a glaciologist at the University of California, Santa Cruz, and lead principal investigator of the TIME project. But because Antarctica is blanketed in ice, glaciers are defined only as rivers of ice that flow within slower-moving ice masses, Tulaczyk said. “These boundaries can move. It’s not a very stable situation.”
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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2576 on: January 13, 2020, 06:34:21 PM »
The linked reference confirms that both:
a) '… a major marine channel > 800 m deep extends to the front of Thwaites Glacier …' and
b) ' beneath the adjacent Dotson and Crosson Ice Shelves … that ice shelves formed since 1993 comprise a distinct population where the draft conforms closely to the underlying bathymetry
… .' 'This indicates that despite rapid basal melting in some areas, these “new” ice shelves are not yet in equilibrium with the underlying ocean system.'

Jordan, T. A., Porter, D., Tinto, K., Millan, R., Muto, A., Hogan, K., Larter, R. D., Graham, A. G. C., and Paden, J. D.: New gravity-derived bathymetry for the Thwaites, Crosson and Dotson ice shelves revealing two ice shelf populations, The Cryosphere Discuss., https://doi.org/10.5194/tc-2019-294, in review, 2020.

https://www.the-cryosphere-discuss.net/tc-2019-294/

Abstract
. Ice shelves play a critical role in the long-term stability of ice sheets through their buttressing effect. The underlying bathymetry and cavity thickness are key inputs for modelling future ice sheet evolution. However, direct observation of sub-ice shelf bathymetry is time consuming, logistically risky, and in some areas simply not possible. Here we use airborne gravity anomaly data to provide new estimates of sub-ice shelf bathymetry outboard of the rapidly changing West Antarctic Thwaites Glacier, and beneath the adjacent Dotson and Crosson Ice Shelves. This region is of especial interest as the low-lying inland reverse slope of the Thwaites glacier system makes it vulnerable to marine ice sheet instability, with rapid grounding-line retreat observed since 1993 suggesting this process may be underway. Our results confirm a major marine channel > 800 m deep extends to the front of Thwaites Glacier, while the adjacent ice shelves are underlain by more complex bathymetry. Comparison of our new bathymetry with ice shelf draft reveals that ice shelves formed since 1993 comprise a distinct population where the draft conforms closely to the underlying bathymetry, unlike the older ice shelves which show a more uniform depth of the ice base. This indicates that despite rapid basal melting in some areas, these “new” ice shelves are not yet in equilibrium with the underlying ocean system. We propose qualitative models of how this transient ice-shelf configuration may have developed.
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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2577 on: January 13, 2020, 06:38:12 PM »
As previously noted, the linked reference indicates: '… that EffCS is a better predictor than TCR of future transient warming under RCP8.5.'

Sanderson, B.: Relating Climate Sensitivity Indices to projection uncertainty, Earth Syst. Dynam. Discuss., https://doi.org/10.5194/esd-2019-77, in review, 2019.

https://www.earth-syst-dynam-discuss.net/esd-2019-77/

Abstract
. Can we summarize uncertainties in global response to greenhouse gas forcing with a single number? Here we assess the degree to which traditional metrics are related to future warming indices using an ensemble of simple climate models together with results from CMIP5 and CMIP6. We consider Effective Climate Sensitivity (EffCS), Transient Climate Response at CO2 quadrupling (T140) and a proposed simple metric of temperature change 140 years after a quadrupling of carbon dioxide (A140). In a perfectly equilibrated model, future temperatures under a non-mitigation scenario are almost perfectly described by T140, whereas in a strongly mitigated future, both ECS and T140 are found to be poor predictors of 21st century warming, and future temperatures are better correlated with A140. However, we show that T140 and EffCS calculated in full CMIP simulations are subject to errors arising from control model drift and internal variability. Simulating these factors in the simple model leads to 30 % relative error in the measured value of T140, but only a 10 % error for EffCS. As such, measured values of EffCS can be better correlated with true TCR than measured values of TCR itself. We propose that this could be an explanatory factor in the previously noted surprising result that EffCS is a better predictor than TCR of future transient warming under RCP8.5.
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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2578 on: January 13, 2020, 06:44:22 PM »
I wonder why those borehole operators are so suprisingly lightly clothed.
Are the sun's rays that warm there? Or is their manual labour very hard?
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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2579 on: January 13, 2020, 07:00:04 PM »
Hefeistos:
Hopefully the coming exascale supercomputers will be able to afford the better models.

The linked reference indicates that SP-E3SM runs represent an improvement over the E3SMv1 runs, but that further improvements are merited:

W.M. Hannah et al. (12 January 2020), "Initial Results from the Super‐Parameterized E3SM", JAMES, https://doi.org/10.1029/2019MS001863

https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1029/2019MS001863

Abstract

Results from the new DOE super‐parameterized (SP) Energy Exascale Earth System Model (SP‐E3SM) are analyzed and compared to the traditionally parameterized E3SMv1 and previous studies using SP models. SP‐E3SM is unique in that it utilizes GPU hardware acceleration, CRM mean‐state acceleration, and reduced radiation to dramatically increase the model throughput and allow decadal experiments at 100km external resolution. It also differs from other SP models by using a spectral element dynamical core on a cubed sphere grid and a finer vertical grid with a higher model top. Despite these differences, SP‐E3SM generally reproduces the behavior of other super‐parameterized models. Tropical wave variability is improved relative to E3SM, including the emergence of a Madden‐Julian Oscillation and a realistic slowdown of Moist Kelvin Waves. However, the distribution of precipitation exhibits indicates an overly frequent occurrence of rain rates less than 1mm d‐1, and while the timing of diurnal rainfall shows modest improvements the signal is not as coherent as observations. A notable grid imprinting bias is identified in the precipitation field and attributed to a unique feedback associated with the interactions between the explicit CRM convection and the spectral element grid structure. Spurious zonal mean column water tendencies due to grid imprinting are quantified − while negligible for the conventionally parameterized E3SM, they become large with super‐parameterization, approaching 10% of the physical tendencies. The implication is that finding a remedy to grid imprinting will become especially important as spectral element dynamical cores begin to be combined with explicitly resolved convection.

Key points
•   SP‐E3SM improves tropical variability like previous super‐parameterized models, but shows modest improvements in the diurnal precipitation
•   The spectral element grid leads to an imprinting bias when used with super‐parameterization and has non‐negligible effects on the climate
•   The throughput of SP‐E3SM was increased to roughly 1.2‐1.4 simulated years per day through hardware (GPU) and algorithmic acceleration
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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2580 on: January 13, 2020, 07:06:56 PM »
The linked reference indicates that the GFDL CM4.0 climate model has high TCR and ECS values, and that: "Energy budget‐based methods for estimating sensitivities based on these quantities underestimate CM4.0's sensitivities when applied to its historical simulations."

M. Winton et al. (11 January 2020), "Climate Sensitivity of GFDL's CM4.0", JAMES, https://doi.org/10.1029/2019MS001838

https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2019MS001838

Abstract
GFDL's new CM4.0 climate model has high transient and equilibrium climate sensitivities near the middle of the upper half of CMIP5 models. The CMIP5 models have been criticized for excessive sensitivity based on observations of present‐day warming and heat uptake and estimates of radiative forcing. An ensemble of historical simulations with CM4.0 produces warming and heat uptake that are consistent with these observations under forcing that is at the middle of the assessed distribution. Energy budget‐based methods for estimating sensitivities based on these quantities underestimate CM4.0's sensitivities when applied to its historical simulations. However, we argue using a simple attribution procedure that CM4.0's warming evolution indicates excessive transient sensitivity to greenhouse gases. This excessive sensitivity is offset prior to recent decades by excessive response to aerosol and land use changes.

Plain Language Summary
We evaluate the climate sensitivity of the Geophysical Fluid Dynamics Laboratory (GFDL) CM4.0 climate model. Climate sensitivity is an important factor determining the magnitude of future climate change under anthropogenic forcing. We find that CM4.0 is a high climate sensitivity model. A simple method for estimating climate sensitivity from historical changes significantly underestimates CM4.0's sensitivity when applied to CM4.0's historical simulation. However, more sophisticated methods that make use of the detailed evolution of global warming identify CM4.0 as most likely too sensitive to anthropogenic forcing.
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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2581 on: January 13, 2020, 07:13:36 PM »
I wonder why those borehole operators are so suprisingly lightly clothed.
Are the sun's rays that warm there? Or is their manual labour very hard?

nanning,

I suspect that it is just above freezing where the borehole operators are working (as there has been recent surface ice melt in this area in recent days see the first image); however, as indicated by the second attached image of Kate Upton in Antarctica; people can dress lightly in such conditions.

ASLR
« Last Edit: January 13, 2020, 10:32:40 PM by AbruptSLR »
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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2582 on: January 13, 2020, 07:23:22 PM »
The application of machine-learning to climate change studies takes many different forms, and the linked reference discusses limits for the application of this approach to assess the uncertainties of global surface ocean CO2 estimates:

Gregor, L., Lebehot, A. D., Kok, S., and Scheel Monteiro, P. M.: A comparative assessment of the uncertainties of global surface ocean CO2 estimates using a machine-learning ensemble (CSIR-ML6 version 2019a) – have we hit the wall?, Geosci. Model Dev., 12, 5113–5136, https://doi.org/10.5194/gmd-12-5113-2019, 2019.

https://www.geosci-model-dev.net/12/5113/2019/

Abstract
Over the last decade, advanced statistical inference and machine learning have been used to fill the gaps in sparse surface ocean CO2 measurements (Rödenbeck et al., 2015). The estimates from these methods have been used to constrain seasonal, interannual and decadal variability in sea–air CO2 fluxes and the drivers of these changes (Landschützer et al., 2015, 2016; Gregor et al., 2018). However, it is also becoming clear that these methods are converging towards a common bias and root mean square error (RMSE) boundary: “the wall”, which suggests that pCO2 estimates are now limited by both data gaps and scale-sensitive observations. Here, we analyse this problem by introducing a new gap-filling method, an ensemble average of six machine-learning models (CSIR-ML6 version 2019a, Council for Scientific and Industrial Research – Machine Learning ensemble with Six members), where each model is constructed with a two-step clustering-regression approach. The ensemble average is then statistically compared to well-established methods. The ensemble average, CSIR-ML6, has an RMSE of 17.16 µatm and bias of 0.89 µatm when compared to a test dataset kept separate from training procedures. However, when validating our estimates with independent datasets, we find that our method improves only incrementally on other gap-filling methods. We investigate the differences between the methods to understand the extent of the limitations of gap-filling estimates of pCO2. We show that disagreement between methods in the South Atlantic, southeastern Pacific and parts of the Southern Ocean is too large to interpret the interannual variability with confidence. We conclude that improvements in surface ocean pCO2 estimates will likely be incremental with the optimisation of gap-filling methods by (1) the inclusion of additional clustering and regression variables (e.g. eddy kinetic energy), (2) increasing the sampling resolution and (3) successfully incorporating pCO2 estimates from alternate platforms (e.g. floats, gliders) into existing machine-learning approaches.
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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2583 on: January 13, 2020, 08:47:58 PM »
Thanks for answering AbruptSLR. I could've checked the temperature myself but saw the frozen ground and thought that Antarctica would not be this warm. Learned something, thanks.

-

Your post on "Initial Results from the Super‐Parameterized E3SM" got me interested in what those parametrizations look like and I found a bit on wikipedia. I'd rather have found some formula's or code.

This might also be of interest to others:

From https://en.wikipedia.org/wiki/Numerical_weather_prediction

the partial differential equations used in the model need to be supplemented with parameterizations for solar radiation, moist processes (clouds and precipitation), heat exchange, soil, vegetation, surface water, and the effects of terrain.

From https://en.wikipedia.org/wiki/Parametrization_(atmospheric_modeling)#Problems_with_increased_resolution

Parameterization in a weather or climate model in the context of numerical weather prediction is a method of replacing processes that are too small-scale or complex to be physically represented in the model by a simplified process. This can be contrasted with other processes—e.g., large-scale flow of the atmosphere—that are explicitly resolved within the models. Associated with these parameterizations are various parameters used in the simplified processes. Examples include the descent rate of raindrops, convective clouds, simplifications of the atmospheric radiative transfer on the basis of atmospheric radiative transfer codes, and cloud microphysics. Radiative parameterizations are important to both atmospheric and oceanic modeling alike. Atmospheric emissions from different sources within individual grid boxes also need to be parameterized to determine their impact on air quality.
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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2584 on: January 14, 2020, 02:58:48 AM »
If iodine in the atmosphere (from the ocean) slows the recovery of ozone hole over Antarctica, then the westerly wind velocities many remain high over the Southern Ocean for some time to come:

Title: "Iodine may slow ozone layer recovery"

https://phys.org/news/2020-01-iodine-ozone-layer-recovery.html

Extract: "A new paper quantifying small levels of iodine in Earth's stratosphere could help explain why some of the planet's protective ozone layer isn't healing as fast as expected.

"The ozone layer is starting to show early signs of recovery in the upper stratosphere, but ozone in the lower stratosphere continues to decline for unclear reasons," said Rainer Volkamer, a CIRES Fellow, CU Boulder professor of chemistry and corresponding author of the new assessment.

"Before now, the decline was thought to be due to changes in how air mixes between the troposphere and stratosphere. Our measurements show there is also a chemical explanation, due to iodine from oceans. What I find exciting is that iodine changes ozone by just enough to provide a plausible explanation for why ozone in the lower stratosphere continues to decline.""
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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2585 on: January 14, 2020, 09:09:26 AM »
Steig doesnt think the ozone hole is causing westerly speedup or southern anuular mode intensification. I asked him this at realclimate couple years ago, he replied he thought that it was not due to ozone hole, rather teleconnect from equatorialish pacific, referred me to a paper he wrote with Ding and others. I kinda agree with him after i looked at the evidence.

He might have changed his mind since, but i have seen no publication by him to that effect. emailing him might get you an answer.

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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2586 on: January 14, 2020, 11:21:45 PM »
The linked reference discusses the ice sheet models used in CMIP6 (ISMIP6); which is an improvement over CMIP5; but in my opinion still errs significantly on the side of least drama:

Lipscomb, W. H., Leguy, G. R., Jourdain, N. C., Asay-Davis, X. S., Seroussi, H., and Nowicki, S.: ISMIP6 projections of ocean-forced Antarctic Ice Sheet evolution using the Community Ice Sheet Model, The Cryosphere Discuss., https://doi.org/10.5194/tc-2019-334, in review, 2020.

https://www.the-cryosphere-discuss.net/tc-2019-334/

Abstract. The future retreat rate for marine-based regions of the Antarctic Ice Sheet is one of the largest uncertainties in sea-level projections. The Ice Sheet Model Intercomparison Project for CMIP6 (ISMIP6) aims to improve projections and quantify uncertainties by running an ensemble of ice sheet models with atmosphere and ocean forcing derived from global climate models. Here, ISMIP6 projections of ocean-forced Antarctic Ice Sheet evolution are illustrated using the Community Ice Sheet Model (CISM). Using multiple combinations of sub-ice-shelf melt parameterizations and calibrations, CISM is spun up to steady state over many millennia. During the spin-up, basal friction parameters and basin-scale thermal forcing corrections are adjusted to nudge the ice thickness toward observed values. The model is then run forward for 500 years, applying ocean thermal forcing anomalies from six climate models. In all simulations, the ocean forcing triggers long-term retreat of the West Antarctic Ice Sheet, including the Amundsen, Filchner-Ronne, and Ross Basins. Mass loss accelerates late in the 21st century and rises steadily over the next several centuries without leveling off. The resulting ocean-forced SLR at year 2500 varies from about 10 cm to nearly 2 m, depending on the melt scheme and model forcing. Relatively little ice loss is simulated in East Antarctica. Large uncertainties remain, as a result of parameterized basal melt rates, missing ocean and ice sheet physics, and the lack of ice–ocean coupling.
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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2587 on: January 15, 2020, 12:09:49 AM »
Quote
The linked reference discusses the ice sheet models used in CMIP6 (ISMIP6); which is an improvement over CMIP5; but in my opinion still errs significantly on the side of least drama:
Why do you think it is still underestimating AGW?

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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2588 on: January 15, 2020, 12:20:11 AM »
Tom, read. It is the projected sea level rise that suggests there will be no drama, not even in 500 years time:
Quote
The resulting ocean-forced SLR at year 2500 varies from about 10 cm to nearly 2 m

Worst case nearly 2 meters SLR due to West-Antarctica in 500 years time?? That is soothing. Burn some more oil.

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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2589 on: January 15, 2020, 01:17:52 AM »
Tom, read. It is the projected sea level rise that suggests there will be no drama, not even in 500 years time:
Quote
The resulting ocean-forced SLR at year 2500 varies from about 10 cm to nearly 2 m

Worst case nearly 2 meters SLR due to West-Antarctica in 500 years time?? That is soothing. Burn some more oil.

Yes, I meant to indicate that the reference erred on the side of least drama (ESLD) with regard to future SLR not necessarily w.r.t. AGW.

Edit: I was too busy previously to note that, by ESLD w.r.t. SLR CMIP6 also likely ESLD w.r.t. the impacts of ice-climate (or ice sheet-climate) feedback mechanisms.
« Last Edit: January 15, 2020, 05:01:28 PM by AbruptSLR »
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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2590 on: January 15, 2020, 01:27:36 AM »
The linked article shows maps of where nitrous oxide has been emitted recently, and reminds us that wildfires is a significant source of nitrous oxide emissions:

Title: "Where nitrous oxide, a greenhouse gas 300-times stronger than CO2, is being emitted"

https://qz.com/1745204/maps-of-nitrous-oxide-emissions-a-potent-greenhouse-gas/

Extract: "If something is burning, nitrous oxide is flowing into the atmosphere. Increasingly, the most concentrated nitrous oxide sources come from humans burning fossil fuels and transforming ecosystems. Natural sources, such as Australia’s currently raging wildfires contribute too (if those fires can even be considered “natural”).

As a greenhouse gas, it gets less attention than carbon dioxide, accounting for just 6% of all emissions in 2017. But it’s a major factor intensifying climate change: NOx, as the gas is known, lasts for a century and is far more potent. It is nearly 300 times stronger than carbon dioxide at trapping heat."
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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2591 on: January 15, 2020, 03:02:37 AM »
The linked article shows maps of where nitrous oxide has been emitted recently, and reminds us that wildfires is a significant source of nitrous oxide emissions:

Title: "Where nitrous oxide, a greenhouse gas 300-times stronger than CO2, is being emitted"

https://qz.com/1745204/maps-of-nitrous-oxide-emissions-a-potent-greenhouse-gas/

Extract: "If something is burning, nitrous oxide is flowing into the atmosphere. Increasingly, the most concentrated nitrous oxide sources come from humans burning fossil fuels and transforming ecosystems. Natural sources, such as Australia’s currently raging wildfires contribute too (if those fires can even be considered “natural”).

As a greenhouse gas, it gets less attention than carbon dioxide, accounting for just 6% of all emissions in 2017. But it’s a major factor intensifying climate change: NOx, as the gas is known, lasts for a century and is far more potent. It is nearly 300 times stronger than carbon dioxide at trapping heat."

Addendum: Preliminary study showing permafrost melt releasing much more NOx than previously assumed.

https://e360.yale.edu/digest/melting-permafrost-releasing-high-levels-of-nitrous-oxide-a-potent-greenhouse-gas

https://www.atmos-chem-phys.net/19/4257/2019/
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AbruptSLR

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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2592 on: January 15, 2020, 04:32:18 PM »
Once fossil fuel companies have invested the capital to find and produce new oil/gas reserves such as those cited in the linked article, they can/will extract those reserves even at operation costs (i.e. even when failing to recover sunk capital development costs):

Title: "Harsh reactions to Norway’s new oil blocks: environmentalists say they are sick and tired of ruthless policy"

https://thebarentsobserver.com/en/ecology-industry-and-energy/2020/01/harsh-reactions-norways-new-oil-blocks-environmentalists-say

Extract: "«I am proud to award 69 new exploration licenses on the Norwegian continental shelf,» said Norwegian Minister of Petroleum and Energy Sylvi Listhaug as she on Tuesday announced this year’s so-called  Awards in Pre-Defined Areas 2019.

Among the licenses are 13 in the Barents Sea, 23 in the Norwegian Sea and 33 in the North Sea. A total of 28 different oil companies are offered ownership interests in one or more of the production licenses."
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AbruptSLR

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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2593 on: January 15, 2020, 05:10:14 PM »
For those who think that I overemphasize the potential economic impacts of following SSP5-8.5 for a few more decades (say until 2050), the linked reference finds that using conventional logic: "Our results show that the largest climate change damages occur under the SSP3-7.0 scenario (involving regional rivalry and high anthropogenic emissions), followed by the SSP3-LowNTCF scenario (which considers significantly reduced NTCF emissions), and that climate change damage costs are expected to grow much faster than global GDP (reaching ~47% of global GDP in 2100)."

YatingChen et al. (2020), "Quantifying economic impacts of climate change under nine future emission scenarios within CMIP6", Science of The Total Environment, Volume 703, 134950, https://doi.org/10.1016/j.scitotenv.2019.134950

https://www.sciencedirect.com/science/article/pii/S0048969719349423

Abstract

The concept of “environmental determinism” suggests that climate conditions played a substantial role in shaping modern society. To minimize the social costs of future climate change and to promote economic development through identification of cost-effective adaptation strategies and mitigation policies, quantitative assessments are needed for obtaining a better understanding of the causal impacts of climate change on human society. In this work, we estimate the economic impacts of climate change during the 21st century under nine CMIP6 scenarios, using the PAGE-ICE integrated assessment model driven by the latest anthropogenic emission and socio-economic projections. Our results show that the largest climate change damages occur under the SSP3-7.0 scenario (involving regional rivalry and high anthropogenic emissions), followed by the SSP3-LowNTCF scenario (which considers significantly reduced NTCF emissions), and that climate change damage costs are expected to grow much faster than global GDP (reaching ~47% of global GDP in 2100). Gaps in adaptation resulting from regional inequalities would lead to higher climate change damages in poorer and warmer regions such as Africa and the Middle East. The outcomes obtained under the SSP1-1.9 and SSP1-2.6 scenarios, in which the warming limit targets of 1.5 °C and 2 °C set forth in the Paris Agreement are considered, respectively, reveal that aggressive mitigation strategies pass a cost-benefit analysis and could significantly reduce the economic impacts of climate change.
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AbruptSLR

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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2594 on: January 15, 2020, 05:37:36 PM »
If I am correct, then the compressive thrust indicate by the string of yellow arrows from the base of the Thwaites Ice Tongue to the Thwaites Eastern Ice Shelf, TEIS, shown on the first image from May 23 2019, is causing the seaward tip of the TEIS to slide eastward across its subsea pinning ridges as can be seen by comparing the relative position of the seaward tip of the TEIS with the 106W longitude line (the red line normal to the red 75S latitude line) in the second image comparing the TEIS on January 15 2020 (left panel) vs November 26 2019 (right panel).  This supposition is support by the compression induced calving indicate on the eastern base of the TEIS shown in the left panel of the second image.  This is not good news.
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Sciguy

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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2595 on: January 15, 2020, 05:39:45 PM »
For those who think that I overemphasize the potential economic impacts of following SSP5-8.5 for a few more decades (say until 2050), the linked reference finds that using conventional logic: "Our results show that the largest climate change damages occur under the SSP3-7.0 scenario (involving regional rivalry and high anthropogenic emissions), followed by the SSP3-LowNTCF scenario (which considers significantly reduced NTCF emissions), and that climate change damage costs are expected to grow much faster than global GDP (reaching ~47% of global GDP in 2100)."

YatingChen et al. (2020), "Quantifying economic impacts of climate change under nine future emission scenarios within CMIP6", Science of The Total Environment, Volume 703, 134950, https://doi.org/10.1016/j.scitotenv.2019.134950

https://www.sciencedirect.com/science/article/pii/S0048969719349423

Abstract

The concept of “environmental determinism” suggests that climate conditions played a substantial role in shaping modern society. To minimize the social costs of future climate change and to promote economic development through identification of cost-effective adaptation strategies and mitigation policies, quantitative assessments are needed for obtaining a better understanding of the causal impacts of climate change on human society. In this work, we estimate the economic impacts of climate change during the 21st century under nine CMIP6 scenarios, using the PAGE-ICE integrated assessment model driven by the latest anthropogenic emission and socio-economic projections. Our results show that the largest climate change damages occur under the SSP3-7.0 scenario (involving regional rivalry and high anthropogenic emissions), followed by the SSP3-LowNTCF scenario (which considers significantly reduced NTCF emissions), and that climate change damage costs are expected to grow much faster than global GDP (reaching ~47% of global GDP in 2100). Gaps in adaptation resulting from regional inequalities would lead to higher climate change damages in poorer and warmer regions such as Africa and the Middle East. The outcomes obtained under the SSP1-1.9 and SSP1-2.6 scenarios, in which the warming limit targets of 1.5 °C and 2 °C set forth in the Paris Agreement are considered, respectively, reveal that aggressive mitigation strategies pass a cost-benefit analysis and could significantly reduce the economic impacts of climate change.

I think everyone on this forum would agree that it's a good thing we're no longer on an SSP 8.5 or 7.0 trajectory anymore.

https://thebreakthrough.org/issues/energy/3c-world


Tom_Mazanec

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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2596 on: January 15, 2020, 05:54:54 PM »
Tom, read. It is the projected sea level rise that suggests there will be no drama, not even in 500 years time:
Quote
The resulting ocean-forced SLR at year 2500 varies from about 10 cm to nearly 2 m

Worst case nearly 2 meters SLR due to West-Antarctica in 500 years time?? That is soothing. Burn some more oil.
Right, I should have read. I thought it would be a huge hairy report that I would not be able to understand. I don’t see how they could have admitted SLR is accelerating but thought it could be 10cm in 2500.
That literally does not even compute, since steady state rise for 500 years is well above that.

jai mitchell

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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2597 on: January 15, 2020, 06:30:42 PM »
The point of the SSP3 70 analysis is that the IAMS use such an outrageous rate of long term economic growth in the face of growing climate change that under even a moderate growth scenario of SSP3, the impacts of cliamate change become significant as a proportion of global economic output.  If the DICE model was right we would need 8 planet earth's worth of resources to produce the economy that Nordhaus proposed by 2100 under >3C of warming.
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pietkuip

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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2598 on: January 15, 2020, 06:35:16 PM »
I don’t see how they could have admitted SLR is accelerating but thought it could be 10cm in 2500.
That literally does not even compute, since steady state rise for 500 years is well above that.

Their models may be computing 10 cm in the year 2500 from West Antarctica alone. I think it would be wildly optimistic to have any confidence in such a calculation, but if that is what the supercomputers tell them after churning for a week that is what they will report.

@Ken: The CO2 concentration trends do not give any reason to think that the world is off the RCP8.5 pathway.

AbruptSLR

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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2599 on: January 15, 2020, 07:35:10 PM »
...
@Ken: The CO2 concentration trends do not give any reason to think that the world is off the RCP8.5 pathway.

I concur that there was little indication of any slowing of fossil CO2 emissions in 2019, per the attached plot.
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Leon C. Megginson