Support the Arctic Sea Ice Forum and Blog

Show Posts

This section allows you to view all posts made by this member. Note that you can only see posts made in areas you currently have access to.


Messages - Hefaistos

Pages: [1] 2 3 ... 13
1
The forum / Re: Forum Decorum
« on: August 01, 2020, 08:52:28 AM »
Can one put oneself on the Ignore list?

2
The forum / Re: Forum Decorum
« on: July 25, 2020, 11:07:27 AM »
bbr, it's a pity that you now resorted to post your things in this 'cellar' of ASIF.

Please copy your interesting posts about your theory to a relevant thread!

It there is no such thread, then start a new thread.

3
For three days after September 11, the Federal Aviation Administration grounded commercial aircraft in the U.S., stranding travelers, hindering mail delivery and interrupting courier service, but for scientists at Penn State and the University of Wisconsin–Whitewater, the three-day shutdown provided a rare glimpse of the climate effects of jet contrails.

The change in the temperature difference was plus 1.1 degree Celsius, equal to plus 2 degrees Fahrenheit, above the 30-year long-term mean diurnal temperature range. The researchers compared the temperature ranges on these three days to those of the three days directly before Sept. 11 and the three days after Sept. 14, finding that the days before and after were similar, but that the three days in question differed by 1.8 degrees Celsius or 3.2 degrees Fahrenheit.

https://www.sciencedaily.com/releases/2002/08/020808075457.htm

That research has later been debunked. The temperature jump during those days was due to a change of low cloudiness.

" Abstract
One of the most visible anthropogenic phenomena in the atmosphere is the occurrence of contrails. The direct effects of contrails on surface temperature are investigated on the basis of the data sets for the cloud cover and surface temperature over the conterminous United States for the period 1971–2001. It is shown that the increase of the average daily temperature range (DTR) over the United States during the three‐day grounding period of 11–14 September 2001 cannot be attributed to the absence of contrails, a subject was debated in several previous studies. The present analysis suggests that the DTR is attributed to the change of low cloudiness."

"We conclude that the increase of the diurnal temperature range over the United States during the three‐day grounding period of 11–14 September 2001 cannot be attributed to the absence of contrails. While missing contrails may have affected the DTR, their impact is probably too small to detect with a statistical significance. The variations in high cloud cover, including contrails and contrail‐induced cirrus clouds, contribute weakly to the changes in the diurnal temperature range, which is governed primarily by lower altitude clouds, winds, and humidity. "

https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2008GL036108

4
I think Aerosols will have a big effect from the Lockdown and Flight grounding/reduced industrial activity, MSM and IPCC will then blame 2020 as an anomoly if we have a 1.75 million km^2 to 2.75 km^2 million minimum this year and say it will not happen again until 2050 etc. The Aerosol masking effect reduction from the Lockdown will cause a permanent 0.5C to 1C increase in global temperatures within months, so around this time June, July, August, this will cause record melting for the Arctic in July and August which can not be compared to past data  on ASIF, bringing forward a BOE event to 2021 to 2024.

"The Aerosol masking effect reduction from the Lockdown will cause a permanent 0.5C to 1C increase in global temperatures within months"?

First of all, the aerosol effect initially will be a local/regional effect, and then spreading to a global effect.
We should have seen the local/regional effect already in the data.
So where are your data for your claim of such a big and permanent temperature increase?
Attach two graphs of current developments in different data sets, as far as I can see we have a pronounced negative trend in the temperature anomalies.

5
Antarctica / Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE
« on: July 22, 2020, 11:41:47 PM »
To me, the linked reference, and associated article, represent an incremental refinement of consensus climate science where the authors limit their definition of ECS to exclude short-term freshwater hosing events, which to me means that only their findings limiting the lower bound of ECS to values above 2.6C are meaningful; while their suggested limits on the upper bound of the true ECS is influenced by their limited definition of ECS.  Therefore, while the climate sensitivity projections from E3SMv1 are not definitive, I believe that the findings of Sherwood et al. (2020) do not eliminate the risk that the higher end CMIP6 ECS values may be in the right range of values (as acknowledged in the last paragraph of the associated article):

S. Sherwood et al. (22 July 2020), "An assessment of Earth's climate sensitivity using multiple lines of evidence", Reviews of Geophysics, https://doi.org/10.1029/2019RG000678

https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1029/2019RG000678
---

Thanks ASLR for linking to this new, major study.

Their approach to not using GCM's is refreshing: "...we avoid relying on GCMs to tell us what values to expect for key feedbacks except where the feedback mechanisms can be calibrated against other evidence." (p 8 of a total of 184 pages)

I believe this is good advice for everyone.

6
ArcticMelt, whether drop in production caused a temperature increase is unknowable because, 1 China restrarted early, 2 lockdowns went into effect in a successive manner or not at all not all at once, 3 while consumption was down, production did not dip as low (change in production type) resulting in a lower decrease of aerosol, 4 very importantly china and other countries rolled back environmental regulations, and finally, 5 aerosols usually take several weeks to breakdown and exit the atmosphere, leaving the bulk of the difference between lockdown emissions and usual emissions in the atmosphere before emissions returned back to normal. This means that the absence of further heating this year is not evidence that the studied effect of aerosol dimming is false.

No, but the total absence of a temperature effect due to Covid lockdowns also doesn't support a strong aerosol dimming effect.
Just to give a classic reference on the importance of aerosols, and the Faustian bargain:
"The importance of knowing the aerosol forcing is shown by considering the following two cases: (1) aerosol forcing about -1 W/m2, such that the net climate forcing is ~ 2 W/m2, (2) aerosol forcing of -2 W/m2, yielding a net forcing ~1 W/m2. Both cases are possible, because of the uncertainty in the aerosol forcing. Which alternative is closer to the truth defines the terms of a "Faustian bargain" that humanity has set for itself."

Hansen, see figs 3 and 4
https://www.giss.nasa.gov/research/briefs/hansen_16/

This also is well worth studying:
"Rethinking the Lower Bound on Aerosol Radiative Forcing" by Bjorn Stevens
J. Climate (2015) 28 (12): 4794–4819.
doi.org/10.1175/JCLI-D-14-00656.1
open access

7
And this, illustrating lockdown effects on air traffic and thus contrails in USA (from another thread).

Previous research on aerosols in connection with major volcanic eruptions (Agung, Pinotubo, etc), show that the (cooling) effect from increased aerosols happens with very little delay in the area first affected.
But we really see no such (warming) effect from the collapse in air traffic in USA.

8
There is also this thread:
"Topic: Temperature signals from Covid-19"
https://forum.arctic-sea-ice.net/index.php/topic,3078.msg262481.html#msg262481

I crosspost the last post in that thread, regarding a possible temperature signal in USA, due to lockdown effects:

Clearly, we see no positive temperature signal from the Covid lockdowns.
Anomalies are continuing down, both globally, and for SH and NH, see the chart with GFS weekly forecast (from Karsten Haustein).

I also checked to temperature data for USA, as one country where the lockdown would assumedly bring a more pronounced signal due to high emissions.
But USA also displays a decline in anomalies.
This is UAH6 satellite data for the LT.


9
Consequences / Re: COVID-19
« on: July 21, 2020, 09:06:38 AM »
What's your problem with my argument?

I see two possibilities here. It's either you genuinely don't know what an anti-vaxxer is (that would be pretty bad), or you are deliberately trying to delude (which would be even worse).

I'll give you the benefit of the doubt here and explain it to you.

Anti-vaxxer are malicious conspiracy theorists who cause incredible harm! They kill people with their willful ignorance.

Your "I'm not an anti-vaxxer per se, but ..." line of argumentation, reminds me of the racist who would say 'i have nothing against jews, but ...' and then some really antisemitic shit follows.

And before you are jumping to conclusions, i did not just call you an antisemite. I'm revealing a pattern that is inherent with conspiratorial thinking.

You try to use some binary logics here. It's either
A: he's unknowing of what anti-vaxxers are/stand for, or
B: he's deluding.
Then you assume that B is false, so A is right: He's unknowing. Bravo!
However, your binary logic is nothing but demagoguery, as your assumption is apparently false. Implicitly you accuse me of delusionism.

What if there was a third alternative,
C: he's informing, he's providing something interesting, worth pondering upon, regarding the dangers of using unproven, new vaccines. He's even providing facts and evidence regarding those dangers, and, via links to wikipedia pages, references to research.

If you read my post #7798 again don't you think that variant 'C' is the correct one?

https://forum.arctic-sea-ice.net/index.php/topic,2996.msg275510.html#msg275510


10
Consequences / Re: COVID-19
« on: July 20, 2020, 01:14:10 PM »
Quote
Many people will refuse to take any vaccines that haven't been proven to be safe for, let's say decades.

The cost of misinformation.
....

Mass vaccination was in the case of swine flu completely unnecessary, and unwarranted.

In this case it was rather the cost of government propaganda and greedy big pharma.
The cost of that greed and that propaganda is carried by those hundreds of (mainly) kids that got their lifes destroyed.

As a result, lot's of people don't trust new vaccines, and won't take them.

11
Consequences / Re: COVID-19
« on: July 20, 2020, 01:04:48 PM »
... I'm not an anti-vaxxer per se, but ...

From where do i know this pattern of arguing? I can't quite remember...

 I'm trying to contribute here with an informative post. Yes, I find that anti-vaxxers have a point against using unproven new vaccines. Hundreds of Swedes, mainly kids, got their lifes destroyed due to bad swine flu vaccines, pushed by big pharma and authoritarian Swedish powers.

 What's your problem with my argument? Please tell then, instead of shooting below the belt.

12
Consequences / Re: COVID-19
« on: July 20, 2020, 10:35:13 AM »
(Sorry if this is off-topic. It doesn't seem to fit in the "Lessons from COVID-19" thread)

<snip>
Now there's an argument for mandatory vaccinations, for everybody, every three months!

This has crossed my mind as well. I am wondering whether 'bad actors' (non-commercial) are seeing a great opportunity for some piggy backing of other stuff in those vaccinations. But I have no knowledge of the possibilities so my wondering looks as conspiracy thinking. Would someone please enlighten me on the possibilities of such a thing? To further 'enslave' or control the little people? A.I. doesn't seem to move fast enough.

Many people will refuse to take any vaccines that haven't been proven to be safe for, let's say decades.
I'm not an anti-vaxxer per se, but we learnt our lesson in Sweden during the swine flu in 2009.
100's of Swedes became invalids for life from the vaccine (Pandemrix) given to the masses, as people developed narcolepsy. Mainly affecting kids.
Pandemrix and some other vaccine were shown to be contaminated with 'unexpected things'.
A new vaccine against Covid will not be considered safe to take by very many people.

Maybe that's why Swedish authorities aim for herd immunity, because they know that vaccination will not be a popular thing this time around.

https://en.wikipedia.org/wiki/Pandemrix
https://en.wikipedia.org/wiki/Narcolepsy

14
Permafrost / Re: Impact of aircraft flights on ice melting
« on: July 19, 2020, 02:58:07 AM »
...

- while it's true that short-wave radiation (UV, X-ray) has major, solar-cycle variable effect on Earth's upper athmosphere, any idea that this process through some unknown cause-effect chain would cause the revert of the trend i mentioned crashes into the same argument: if this would be the main cause, then we would clearly see 11-year pattern in minimum arctic sea ice: the loss would occur in "dips and recoveries" manner, or at very least "dips and pauses", over the decades since 1979. But we don't. This reversal is one unique event in the history of satellite observations, so massive that it also is clearly reflected by extent annual minimums as well, with 2012 to this day holding the minimum record.

This is OT, but is an interesting topic in the more longterm developments only, i.e. the so called Milankovich cycles (41 - 100 k years).
And yes, there is an almost perfect match between summer insolation and the changes in ice volume.
See Roe, 2006.
"In defense of Milankovitch"
doi.org/10.1029/2006GL027817

From the abstract: " The Milankovitch hypothesis is widely held to be one of the cornerstones of climate science. Surprisingly, the hypothesis remains not clearly defined despite an extensive body of research on the link between global ice volume and insolation changes arising from variations in the Earth's orbit. In this paper, a specific hypothesis is formulated. Basic physical arguments are used to show that, rather than focusing on the absolute global ice volume, it is much more informative to consider the time rate of change of global ice volume. This simple and dynamically‐logical change in perspective is used to show that the available records support a direct, zero‐lag, antiphased relationship between the rate of change of global ice volume and summertime insolation in the northern high latitudes...."
The attached figure compares the insolation anomaly (green curve) during June at 65 N with the best fit of change of ice volume to the orbital variations (black curve). Two metrics of ice volume are used, and show similar results.

Paper is open access.

15
The forum / Re: Forum Decorum
« on: July 18, 2020, 11:55:42 PM »
Is there a name for the class of people like myself to contrast with Deniers and Doomers? People who think that we're fucked, but not completely. I consider myself pro-salvage.

Would be nice if there was a simple term for us.

My inspiration is the Jews who fought back in the Warsaw Ghetto uprising rather than submit to the assembly line death march. They had no chance to get out alive, but they caused the bad guys to expend resources which made a difference to some anonymous people they would never know. The people on Flight 93 did something similar.

Hopium implies some fairy tale outlook. I don't see fairy tales. I see a lot of death and destruction....and life going on.

Realist.

16
Consequences / Re: Temperature signals from Covid-19
« on: July 18, 2020, 09:36:54 AM »
Clearly, we see no positive temperature signal from the Covid lockdowns.
Anomalies are continuing down, both globally, and for SH and NH, see the chart with GFS weekly forecast (from Karsten Haustein).

I also checked to temperature data for USA, as one country where the lockdown would assumedly bring a more pronounced signal due to high emissions.
But USA also displays a decline in anomalies.
This is UAH6 satellite data for the LT.

17
Policy and solutions / Re: Cars, cars and more cars Part Deux
« on: July 17, 2020, 11:20:47 AM »
Car tyres are major source of ocean microplastics – study
Wind-borne microplastics are a bigger source of ocean pollution than rivers, say scientists

"an average tyre loses 4kg during its lifetime"
That's 16 Kg per set of tires per car. Much more than the lost fibers from washing clothes

https://www.theguardian.com/environment/2020/jul/14/car-tyres-are-major-source-of-ocean-microplastics-study
...

I never rode in a car with plastic tyres?
Aren't tyres made of rubber? - which btw is based on a natural product.
Funny that they don't even mention the word rubber in the Guardian article.
I suppose that plastics and rubber have rather different chemical half-lifes, and environmental effects.

18
Science / Re: Solar cycle
« on: July 16, 2020, 10:30:11 PM »
This is a recent paper estimating TSI, albedo, and OLR

"Measurement of the Earth Radiation Budget at the Top of the Atmosphere—A Review"
by Steven Dewitte and Nicolas Clerbaux,
 Remote Sens. 2017, 9(11), 1143;

"TSI measurements with good stability have been available since 1984. They reveal a variation of the TSI in phase with the 11-year sunspot cycle, with an amplitude of the order of 1 W/m2
. The currently-ending solar cycle 24 has a low amplitude compared to the preceding ones.
The TIM TSI instruments have a different viewing geometry as compared to the classical TSI instruments, which results in a lower absolute value of the measured TSI. Reconciling the classical DIARAD/SOVIM and the new TIM/TCTE instrument, the TSI level at solar minimum is estimated to be 1362.0 +/− 0.9 W/m2
.
The ERB measurements have sufficient stability to track the temporal variability of the EEI driving climate change, but they can not measure its absolute value with sufficient accuracy. Combining the ERB measurements with independent estimates of the EEI from OHC, we obtain the most likely values of the OLR of 238.0 W/m2
and of the RSF of 101.6 W/m2—corresponding to an albedo of 29.8%
—for the period 2000–2005."

https://doi.org/10.3390/rs9111143

https://www.mdpi.com/2072-4292/9/11/1143/htm

19
Arctic sea ice / Re: When will the Arctic Go Ice Free?
« on: July 16, 2020, 06:27:22 AM »


Quote
An "ice-free" Arctic Ocean is often defined as "having less than 1 million square kilometers of sea ice", because it is very difficult to melt the thick ice around the Canadian Arctic Archipelago.[20][21][22] The IPCC AR5 defines "nearly ice-free conditions" as sea ice extent less than 106 km2 for at least five consecutive years.[4]

10^6 km2

20
Antarctica / Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE
« on: July 15, 2020, 10:08:43 AM »
It's shocking that 2020 could be the warmest year on record while the cold tongue is strong in the eastern equatorial Pacific. This may not be a La Niña year but it certainly is not an El Niño when we normally see the highest global temperatures.

There's some hard to explain things happening with the intense end stratospheric warmings in the northern hemisphere the past 2 years.  The physics is beyond me but what's happening is consistent with research papers that report an increase in the up - down circulation from the troposphere to the stratosphere and back. Whatever, these strong end warmings apparently have transferred momentum from the winter polar vortex downwards to the polar jet stream in the troposphere in May of both years and pushed the jet stream south. That has led to more heat transfer by Rossby waves to the polar region.

I await the publication of research papers by atmospheric physicists to get the story right. I'm just giving you my best take that something is amiss.

Which part of the stratosphere (altitude) would that be?
The lower stratosphere has declining anomalies for 30 years or so. See attached chart.
Some disturbances in the beginning of 2020, but they are in SH.

The second chart shows the Northern Polar region. Also here we have pronounced negative trend.
Lot's of volatility, but the beginning of 2020 actually shows big drops.
This is satellite data from UAH6.

21
Consequences / Re: COVID-19
« on: July 15, 2020, 12:18:46 AM »
In the US, covid is killing a far larger percentage of Blacks, Latinos, and Native Americans than of Whites.

Is the reason genetic or socio-economic? I'm asking out of curiosity.

Quote
Are those groups also guilty of excessive fear for this virus?

No, the reason could simply be that they are exploited more by a system that seeks to profit off of people's health. As minorities are structurally kept in a position of unequal opportunities, their health is probably less than that of most Whites. And then, when a virus comes along, even if it's similar to influenza...

The problem is the system, not the virus.

...

Neven, while lying low, don't eat chicken from the US.
US chicken business is part of a system that helps fund the Kochs and the Trumps.

"At the Oasis truck stop, the Mountaire employee expressed disgust that, in the middle of a pandemic, she might be replaced by someone paid even worse—a worker who had likely come from a foreign land to seek opportunity. “I’m telling you, Donald Trump wants to make this a Third World country,” she said. “Treat them like slave dogs. They come to the Land of the Free—but, honey, it isn’t free anymore.” "

https://www.newyorker.com/magazine/2020/07/20/how-trump-is-helping-tycoons-exploit-the-pandemic

22
Science / Re: Solar cycle
« on: July 14, 2020, 10:30:57 AM »
Hefaistos,

Your comments do not address the errors I pointed out.

The amount of solar energy impinging upon each square meter of the Earth is ~1360 W/m^2 divided by 4, since the Earth is a sphere.

Until you acknowledge this fact, you will continue to calculate the impact of a Maunder Minimum incorrectly.

Yes, of course, I was only mentioning the changes in solar irradiance. As you say, WHF, the incoming absorbed solar energy per unit surface area is S(1-a)/4
where a is albedo. On average, albedo is assumed to be around 0.3

The solar constant varies a bit over time, to get even numbers let's have it at S = 1360 W/m^2
The solar radiation at the TOA averaged over the whole surface of the earth = 340 W/m^2
The solar radiation absorbed by the earth’s climate system around 240 W/m^2 (depending on albedo).
The approximate radiation from the earth’s climate system at TOA also equals 240W/m^2 if we have energy balance (steady state). (which we don't, as the EEI is around 1 W/m^2 .

The solar 'constant' (S) varies a bit over time with the 11 year cycle, as seen in the CMIP6 forcing chart, its amplitude is about 1 W/m^2 during strong solar cycles, whereas only half of that during weak cycles.

Secondly, if we take the above figure for the Maunder minimum, it means a change in S with around -0.8 W/m^2 in S as a long term trend change.
At surface, with constant albedo it then adds about -0.14 W/m^2 in as a long term trend change in forcing.
I attach a chart with satellite measurements during 1978-1999. The absolute irradiation levels are much higher in those readings, but for some reason (why?) they have been aligned at the lower level of around 1361. (Also Hansen use the higher values)

23
Antarctica / Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE
« on: July 13, 2020, 11:07:22 AM »
The Liu et al paper refers to other research that uses AMOC data up until 2017, which are claimed to show a slight slowdown of the AMOC. Developments since then seem to contradict that. The latest AMOC data are from September 2018.

Desbruyères et al, 2019, Ocean Sci., 15, 809–817 clearly demonstrate that the AMOC is currently strengthening, and they even give a bold forecast for the coming years:

"An easily observed surface quantity – the rate of warm to cold transformation of water masses at high latitudes – is found to lead the observed AMOC at 45∘ N by 5–6 years and to drive its 1993–2010 decline and its ongoing recovery, with suggestive prediction of extreme intensities for the early 2020s."

AMOC is forecasted to have "extreme intensities" in the coming years, as the AMOC is 'downstream' with a lag of 5 to 6 years from the already intensified warm to cold transformation of water masses at high latitudes.

CMIP6 models should probably try to include these recent research findings as well.
Also, Liu et al use the already defunct RCP8.5 for all their GIGO simulations.

24
Science / Re: Solar cycle
« on: July 13, 2020, 10:15:26 AM »
...
1360.2 vs 1361 (annual average and that is only TOA).
...

As the Earth Energy Imbalance at TOA is less than 1 W/sq.m. this effect is quite substantial.


Hefaistos,

You've made two simple errors in this statement.

1. TOA irradiance of ~1360 must be applied to the surface of the Earth, reducing the difference between Maunder Minimum and normal irradiance by a factor of 4. 1360 is the amount received on the sunlit side of a flat plate, the amount received by a sphere is 1/4 of that.

2. Albedo reduces the effect further.


The net reduction is therefore not 1361 - 1360.2 = 0.8

It is more like 240.5 - 240.35 = 0.15 W/m^2

The heating of the Earth is a result of the Earth Energy Imbalance at TOA. See attached chart from CERES.
93% of the heat uptake goes into the Ocean, and is measured as an increase in the ocean heat content, ohc.
The rest goes to the atmosphere.
What is measured at the surface is of course relevant for those that live there. But the surface temperatures are in essence just a secondary aspect in relation to EEI. The same with albedo.
This is what the 'ceres people' write:
"The planetary heat uptake accounts for the entire energy added to or removed from the climate system. It arguably provides a more fundamental measure of global warming than global mean surface temperature, which is influenced by other decadal processes internal to the climate at the air-sea interface."

Thus, I didn't make any error at all.

https://ceres.larc.nasa.gov/science/

25
Antarctica / Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE
« on: July 13, 2020, 12:16:22 AM »
... the current slowing of the AMOC ,,,
...

Title: "Carbon Lurking in Deep Ocean Threw Ancient Climate Switch, Say Researchers"

https://www.ldeo.columbia.edu/news-events/carbon-lurking-deep-ocean-threw-ancient-climate-switch-say-researchers

Extract: "The strength of the AMOC is believed to fluctuate naturally, but it appears to have weakened by an unusual 15 percent since the mid-20th century.
...

AMOC isn't currently slowing.

The following links to research papers show the opposite, the AMOC seems to be strengthening currently.
https://www.researchgate.net/publication/338658885_Pending_recovery_in_the_strength_of_the_meridional_overturning_circulation_at_26_N

https://agupubs.onlinelibrary.wiley.com/doi/pdf/10.1002/2017GL076350

https://os.copernicus.org/articles/15/809/2019/

These results and other research indicating a current strengthening of the AMOC have been discussed in the following posts:

https://forum.arctic-sea-ice.net/index.php/topic,2205.msg240256.html#msg240256
https://forum.arctic-sea-ice.net/index.php/topic,2205.msg272111.html#msg272111
https://forum.arctic-sea-ice.net/index.php/topic,2205.msg271113.html#msg271113

26
Science / Re: Solar cycle
« on: July 12, 2020, 12:30:29 AM »
Also the CMIP6 data probably does not forecast it but uses it as an input.

Correct.
"Abstract. This paper describes the recommended solar forcing dataset for CMIP6 and highlights changes with respect to CMIP5. The solar forcing is provided for radiative properties, namely total solar irradiance (TSI), solar spectral irradiance (SSI), and the F10.7 index as well as particle forcing, including geomagnetic indices Ap and Kp, and ionization rates to account for effects of solar protons, electrons, and galactic cosmic rays. This is the first time that a recommendation for solar-driven particle forcing has been provided for a CMIP exercise. The solar forcing datasets are provided at daily and monthly resolution separately for the CMIP6 preindustrial control, historical (1850–2014), and future (2015–2300) simulations. For the preindustrial control simulation, both constant and time-varying solar forcing components are provided, with the latter including variability on 11-year and shorter timescales but no long-term changes. For the future, we provide a realistic scenario of what solar behavior could be, as well as an additional extreme Maunder-minimum-like sensitivity scenario. This paper describes the forcing datasets and also provides detailed recommendations as to their implementation in current climate models."

References:

https://gmd.copernicus.org/articles/10/2247/2017/

https://solarisheppa.geomar.de/cmip6

27
Science / Re: Solar cycle
« on: July 11, 2020, 10:44:04 AM »
...
1360.2 vs 1361 (annual average and that is only TOA).
...

As the Earth Energy Imbalance at TOA is less than 1 W/sq.m. this effect is quite substantial.

This was written by J. Hansen, known for not being a denier, 8 years ago:

"If other climate forcings were unchanged, increasing Earth's radiation to space by 0.5 W/m2 would require reducing CO2 by ~30 ppm to 360 ppm. However, given that the imbalance of 0.58±0.15 W/m2 was measured during a deep solar minimum, it is probably necessary to increase radiation to space by closer to 0.75 W/m2, which would require reducing CO2 to ~345 ppm, other forcings being unchanged. Thus the Earth's energy imbalance confirms an earlier estimate on other grounds that CO2 must be reduced to about 350 ppm or less to stabilize climate (Hansen et al., 2008)."

If we go into a Maunder minimum, as the CMIP6 forcings show, it will give us several decades more to implement renewables etc.

https://www.giss.nasa.gov/research/briefs/hansen_16/

28
The forum / Re: Arctic Sea Ice Forum Humor
« on: July 08, 2020, 03:08:33 PM »
Free-hand Extrapolation of the melting curve of Arctic 08072020: ;D ;)

"Free-hand Extrapolation" - you're too honest! Should have said it's a 27th degree polynomial fitted with a strange attractor.

29
Science / Re: Solar cycle
« on: July 08, 2020, 01:03:00 PM »
The solar forcing implemented in the new generation of CMIP6 models seem to forecast a Maunder minimum. Solar cycles declining all the way to 2100.

Figure from attached pdf page 9.

30
Another paper about the ongoing strengthening of the AMOC:

"Pending recovery in the strength of the meridional overturning circulation at 26°N"

by Moat et al, in Ocean Science, forthcoming  (still in peer review)

Abstract. The strength of the Atlantic meridional overturning circulation (AMOC) at 26°N has now been continuously measured by the RAPID array over the period Apr 2004 - Sept 2018. This record provides unique insight into the variability of the large-scale ocean circulation, previously only measured by sporadic snapshots of basin-wide transports from
hydrographic sections. The continuous measurements have unveiled striking variability on timescales of days to a decade, driven largely by wind-forcing, contrasting with previous expectations about a slowly-varying, buoyancy forced large-scale ocean circulation. However, these measurements were primarily observed during a warm state of the Atlantic Multidecadal
Variability (AMV) which has been steadily declining since a peak in 2008-2010. In 2013-2015, a period of strong buoyancyforcing by the atmosphere drove intense watermass transformation in the subpolar North Atlantic and provides a unique opportunity to investigate the response of the large-scale ocean circulation to buoyancy forcing. Modelling studies suggest that the AMOC in the subtropics responds to such events with an increase in overturning transport, after a lag of 3-9 years. At 45°N, observations suggest that the AMOC may already be increasing. ..."

https://www.researchgate.net/publication/338658885_Pending_recovery_in_the_strength_of_the_meridional_overturning_circulation_at_26_N

Figure 3 The total AMOC at 10-day resolution (a), can be decomposed into a seasonal cycle (b), interannual variability (c)...

31
The linked reference confirms that the AMOC is projected to continue slowing with continued global warming:

Wei Liu  et al. (26 Jun 2020), "Climate impacts of a weakened Atlantic Meridional Overturning Circulation in a warming climate", Science Advances, Vol. 6, no. 26, eaaz4876, DOI: 10.1126/sciadv.aaz4876

https://advances.sciencemag.org/content/6/26/eaaz4876

Abstract
While the Atlantic Meridional Overturning Circulation (AMOC) is projected to slow down under anthropogenic warming, the exact role of the AMOC in future climate change has not been fully quantified. Here, we present a method to stabilize the AMOC intensity in anthropogenic warming experiments by removing fresh water from the subpolar North Atlantic. This method enables us to isolate the AMOC climatic impacts in experiments with a full-physics climate model. Our results show that a weakened AMOC can explain ocean cooling south of Greenland that resembles the North Atlantic warming hole and a reduced Arctic sea ice loss in all seasons with a delay of about 6 years in the emergence of an ice-free Arctic in boreal summer. In the troposphere, a weakened AMOC causes an anomalous cooling band stretching from the lower levels in high latitudes to the upper levels in the tropics and displaces the Northern Hemisphere midlatitude jets poleward.

Some in this thread have suggested that the recent observed cooling of the lower levels of the troposphere is an indication that climate sensitivity is relatively low; however, the quoted reference indicates that instead it is an indication that the AMOC is slowing (see the bolded text in the abstract); which to me is an indication that in coming decades TCR will be much higher (near 2.93C) than assumed by consensus climate science.

What if the AMOC instead is in a strengthening cycle? This is suggested be several recent papers. How do you then explain the decreasing tropospheric temperatures?

"Surface predictor of overturning circulation and heat content change in the subpolar North Atlantic"
Desbruyères et al, 2019, Ocean Sci., 15, 809–817

Abstract
The Atlantic Meridional Overturning Circulation (AMOC) impacts ocean and atmosphere temperatures on a wide range of temporal and spatial scales. Here we use observational datasets to validate model-based inferences on the usefulness of thermodynamics theory in reconstructing AMOC variability at low frequency, and further build on this reconstruction to provide prediction of the near-future (2019–2022) North Atlantic state. An easily observed surface quantity – the rate of warm to cold transformation of water masses at high latitudes – is found to lead the observed AMOC at 45∘ N by 5–6 years and to drive its 1993–2010 decline and its ongoing recovery, with suggestive prediction of extreme intensities for the early 2020s. We further demonstrate that AMOC variability drove a bi-decadal warming-to-cooling reversal in the subpolar North Atlantic before triggering a recent return to warming conditions that should prevail at least until 2021. Overall, this mechanistic approach of AMOC variability and its impact on ocean temperature brings new key aspects for understanding and predicting climatic conditions in the North Atlantic and beyond."

From the Conclusions:
"In this paper we have provided observationally based evidence of a tight causal relationship between low-frequency changes in the rate of surface-forced water mass transformation in the eastern SPG /Subpolar Gyre/, the variability in the overturning circulation at 45∘ N, and ocean heat content trends in the SPG. The 5-year delay between surface property changes in the SPG and downstream circulation changes suggests good skills for short-term predictability in the region from the sole use of ocean surface and air–sea interface measurements. Here, a strong intensification of the overturning and associated heat transport from 2010 is found to persist until the early 2020s, driving a new significant reversal of climatic condition in the SPG as temperatures rapidly rise from their last minimum of 2017. "

Enjoy the full text:
https://os.copernicus.org/articles/15/809/2019/

Caption Figure 4. The AMOC and SFOC time series. (a) Annual anomalies in the maximum AMOC (blue) and the maximum SFOC (red) at 45 N (in Sv), with the latter shifted 5 years forward (lag of maximum correlation). The reference (time-mean) period is 1996–2013. Thick lines show 7-year low-pass-filtered time series. The right-hand side axis displays the corresponding heat transport anomalies. The original time line for SFOC is given in the top x axis. (b) The 7-year low-pass-filtered time series of anomalies in the maximum SFOC at 45 N (red – shifted 5 years forward), the maximum SFOC at the OSNAP line (green – shifted 4 years forward) decomposed into contributions from the eastern (thin) and western (dashed) basins, and the maximum SFOC at the GIS sills (yellow – shifted 3 years forward). Shading indicates the ensemble standard errors for each variable.

Caption  Figure 5. OHC time series. Detrended anomalies in OHC within
the upper SPG (0–1000 m; 10–70W, 45–65 N; black, in joules)
and MHT -driven OHC anomalies north of 45 N (blue, in joules).
Shading indicates the ensemble standard errors for each variable.
The SFOC -driven OHC prediction for 2017–2022 is shown in red,
with its associated error based on the historical predictive skills of
SFOC (Eq. 6). The green patch indicates the “cold blob” era driven
by extreme air–sea flux events (Josey et al., 2018).

32

Here is another reminder that the quoted research indicates that the AMOC is currently slowing (particularly since 2015); which is a major risk factor for high values of TCR in coming decades:


ASLR, your statement (bolded by me) is not correct.
AMOC is stable during the period from 2015 to 2019, even showing a slight increase.
Please see the charts i posted in reply #3424 and reply #3425:

The RAPID arrays show:
At 26N, a slight increase
At Upper Mid Ocean, stable
Florida Straits, stable
Ekman at 26N, a slight increase
OVIDE section, a slight increase

What's the evidence you can provide that "AMOC is currently slowing (particularly since 2015)"?

https://forum.arctic-sea-ice.net/index.php/topic,2205.msg271113.html#msg271113

I believe that Smeed et al got it right in their recent paper, when they write:
"Our results show that the previously reported decline of the AMOC (Smeed et al., 2014) has been arrested, but the length of the observational record of the AMOC is still short relative to the time scales of importantdecadal variations that exist in the Atlantic. Understanding is therefore constantly evolving. What we identify as a changed state of the AMOC in this study may well prove to be part of a decadal oscillation superposed on a multidecadal cycle."

In other words, what we're seeing is natural variations, and there is currently no evidence of a declining AMOC, specifically not since 2015.

https://agupubs.onlinelibrary.wiley.com/doi/pdf/10.1002/2017GL076350

33
Per the linked open access reference:

"The AMOC has been observed to slow down over the past decade in the Rapid Climate Change (RAPID) array at 26.5°N in the North Atlantic, although this AMOC slowdown can be part of natural climate variability, considering the relatively short observational period."

Wei Liu et al. (26 Jun 2020), Climate impacts of a weakened Atlantic Meridional Overturning Circulation in a warming climate", Science Advances, Vol. 6, no. 26, eaaz4876< DOI: 10.1126/sciadv.aaz4876

https://advances.sciencemag.org/content/6/26/eaaz4876

That whole paper is built on computer simulations with a GCM model and applying only the RCP8.5 scenario.
That alone disqualifies the results, as we aren't following the RCP8.5 due to the strong development of renewables.

Secondly, the paper enforces a very strong decline in the AMOC, a decline that has no support in the actual data that we have today, see chart.
Caption: "Fig. 1 AMOC strength and global mean surface air temperature in CCSM4 historical and RCP8.5 simulations and sensitivity experiment AMOC_fx. (A) From 1850 to 1980, the AMOC strength is adopted from CCSM4 historical simulation (purple, ensemble mean; light purple, ensemble spread). After 1980, the AMOC strength from CCSM4 historical and RCP8.5 simulations (AMOC_fx) is shown as green (purple) curve for ensemble mean and light green (light purple) shading for ensemble spread. The AMOC strength is defined as the maximum of the annual mean stream function below 500 m in the North Atlantic."

Furthermore, the paper uses AMOC data up until 2017 which are claimed to show a slight slowdown of the AMOC. Developments since then seem to contradict that.
As Smeed et al write:
"Our results show that the previously reported decline of the AMOC (Smeed et al., 2014) has been arrested, but the length of the observational record of the AMOC is still short relative to the time scales of importantdecadal variations that exist in the Atlantic. Understanding is therefore constantly evolving. What we identify as a changed state of the AMOC in this study may well prove to be part of a decadal oscillation superposed on a multidecadal cycle."


https://agupubs.onlinelibrary.wiley.com/doi/pdf/10.1002/2017GL076350

34
Consequences / Re: Temperature signals from Covid-19
« on: July 01, 2020, 01:35:59 PM »
We have a pronounced negative temperature anomaly signal during the second quarter of 2020.
We expected a positive anomaly signal due to the reduced aerosols as a result of world-wide lockdowns.

So why do we get the opposite?

Attached is a temperature chart, including a forecast for the next week as well.

35
The theme of AMOC slowdown is also covered in this post:

https://forum.arctic-sea-ice.net/index.php/topic,2205.msg240256.html#msg240256

The chart gives no support at all for a slowdown.

"A time series of AMOC transport (MOCρ ) at the OVIDE section (eastern subpolar gyre: Portugal to Cape Farewell) for 1993–2017, constructed from altimetry and hydrography. The gray line is from altimetry combined with a time-mean of Argo velocities; the green curve is low-pass filtered using a 2-year running mean. The black curve is from altimetry and Argo. Red circles are estimates from OVIDE hydrography with associated errors given by the red lines. The mean of the gray curve is given by the black dashed line (Updated from Mercier et al., 2015)."

36
I find it disturbing that the linked reference indicates that many consensus climate scientists primarily attribute the North Atlantic warming hole (or Cold Blob) to a slow-down of that AMOC; while in fact both the Cold Blob and the slow-down of the AMOC is primarily related to meltwater hosing from Greenland.  This indicates to me that many consensus climate science models should be upgraded to include freshwater hosing from meltwater:

Keil, P. et al. (2020) Multiple drivers of the North Atlantic warming hole, Nature Climate Change, doi:10.1038/s41558-020-0819-8

https://www.nature.com/articles/s41558-020-0819-8

Abstract: "Despite global warming, a region in the North Atlantic ocean has been observed to cool, a phenomenon known as the warming hole. Its emergence has been linked to a slowdown of the Atlantic meridional overturning circulation, which leads to a reduced ocean heat transport into the warming hole region. Here we show that, in addition to the reduced low-latitude heat import, increased ocean heat transport out of the region into higher latitudes and a shortwave cloud feedback dominate the formation and temporal evolution of the warming hole under greenhouse gas forcing. In climate model simulations of the historical period, the low-latitude Atlantic meridional overturning circulation decline does not emerge from natural variability, whereas the accelerating heat transport to higher latitudes is clearly attributable to anthropogenic forcing. Both the overturning and the gyre circulation contribute to the increased high-latitude ocean heat transport, and therefore are critical to understand the past and future evolutions of the warming hole."

See also:

Title: "Scientists shed light on human causes of North Atlantic’s ‘cold blob’"

https://www.carbonbrief.org/scientists-shed-light-on-human-causes-of-north-atlantics-cold-blob

Extract: "Previous research has linked the warming hole to a weakening of an ocean current in the North Atlantic, which brings heat up from the tropics.

Now a new study – published in Nature Climate Change – suggests that a number of other factors are also involved. These include “changes in the high latitude ocean circulation” and the cool sea surface creating “more low-level clouds”, the lead author tells Carbon Brief."

There is a lot of talk about a slowdown of the AMOC, and a lot of CMIP modelling takes it as a given thing in their future scenarios.

However, the evidence for a slowdown of AMOC is rather weak, as it relies on data that are disputed.
The causes of the eventual slowdown are also disputed.

No evidence of a slowdown are to be seen in recent data. Here as measured at different places.
(data taken from KNMI site)

37
Consequences / Re: COVID-19
« on: June 29, 2020, 11:41:16 AM »
A thorough analysis of C-19 in Sweden by a competent statistician, Nic Lewis, he concludes:

"Notwithstanding that a month ago antibodies were only detected in 6.3% of the Swedish population, the declining death rate since mid-May strongly suggests that the herd immunity threshold had been surpassed in the three largest regions, and in Sweden as a whole, by the end of April.

In the absence of a change in trends, it seems likely that the epidemic will peter out after a thousand or so more deaths, implying an overall infection fatality rate of 0.06% of the population (0.04% excluding COVID-19 deaths of people in care homes). This is broadly comparable to excess deaths from influenza infections over two successive above-average seasons, such as 2016–17 plus 2017–18."

https://www.nicholaslewis.org/the-progress-of-the-covid-19-epidemic-in-sweden-an-analysis/

38

Something is going wrong at Moyhu as for instance, the first attached image from the linked Moyhu website shows that no month in 2020 has been the warmest on record.

http://www.moyhu.org.s3.amazonaws.com/data/freq/ncep.html

Yet, NOAA, NASA and Copernicus (see the second attached image where Hausfather uses Copernicus data thru the end of May 2020 to project that 2020 will be the warmest year on record) all indicate that all months thru May 2020 were the warmest on record.

Thus until Moyhu's data falls in line with the observed NOAA, NASA and Copernicus observed data, I am inclined to ignore all data from Moyhu.

There seems to be some issues with the NCEP V1 data, or the feed.
It has been discussed on the Moyhu blog, also by Karsten Haustein (sign. KarSteN):

https://moyhu.blogspot.com/2020/05/ncepncar-reanalysis-surface-temperature.html
https://moyhu.blogspot.com/2020/06/ncepncar-reanalysis-may-2020-surface.html

Karsten Haustein discusses issues with the NCEP reanalysis in depth here:
http://www.karstenhaustein.com/reanalysis/info.php

39
Geron,
your examples are valid, but not relevant.
Gravity always pulls downward.
The Nile always flows only in one direction.
Planets and stars always move in the same way.
By plain observation you can spot reliable patterns.

But what about cloud feedbacks? Some of the clouds have positive feedback, some have negative.
Cloud feedback tend to be negative in the tropics, positive elsewhere.
Aerosols play an important role, but how, and where, and for which types of clouds?
Convective processes and cloud feedbacks happen on smaller scales (grid sizes) than the models can handle. And even if they had this data, there isn't enough computational capacity available.
You don't even have observations on the relevant scale.
Without observations you have no valid data.
Without theories that cover all relevant cloud and aerosol processes, you have no valid model.
Without computational capacity your deficient data and model built on incomplete theories will indeed produce only GIGO.

There is a research initiative to resolve these issues, The World Climate Research Programme (WCRP) Grand Challenge on Clouds, Circulation, and Climate Sensitivity.
They write in a white paper: "Limited understanding of clouds is the major source of uncertainty in Climate Sensitivity, but also contributes substantially to persistent biases in modelled circulation systems..."
"The spread of climate sensitivity estimates is unacceptably large, mostly as a result of uncertain changes in clouds. This uncertainty can be thought of as the ‘cloud problem’. The cloud problem contributes to an inability to usefully constrain the upper bound, and the relative reliability, of differing estimates of climate sensitivity."

https://wcrp-climate.org/component/content/article/61-gc-clouds-circulation?catid=30&Itemid=267

40
...
Seems relevant to ask, have these CMIP models with unbelievably high ECS values got their fundamental physics reg. clouds and water vapor right?

First, no model is perfect but some models are useful (& thus should not be ignored). 

Models that can be characterized as GIGO should be ignored.
...

Of course if the CMIP models are assuming that feedback from aerosol emissions are less negative than that feedback actually is then then the CMIP5 projections might be matching the recently observed record by using two wrongs to make a right; while the high-end CMIP6 projections might not match the observed record as well but may be projecting the future better if/when anthropogenic aerosol emissions are reduced (such as they have been for the first five months of 2020 when the month GMSTA values have been at record highs).  Thus, when uncertainty is involved who is to say what constitutes garbage in-garbage out (GIGO) w.r.t. modeling; however, the climate risks associated with the high-end CMIP6 projections are so high as to justify the adoption of the Precautionary Principle.

New research paper published that evaluates CMIP6 models.
"Context for interpreting equilibrium climate sensitivity and transient climate response from the CMIP6 Earth system models" by Meehl et al. Science Advances  24 Jun 2020, Vol. 6, no. 26,
From the Abstract
"....Here we review and synthesize the latest developments in ECS and TCR values in CMIP, compile possible reasons for the current values as supplied by the modeling groups, and highlight future directions. Cloud feedbacks and cloud-aerosol interactions are the most likely contributors to the high values and increased range of ECS in CMIP6."

Accompanying presentation of the research:
"Increased warming in latest generation of climate models likely caused by clouds
New representations of clouds are making models more sensitive to carbon dioxide"
Jun 24, 2020 - by Laura Snider

"“Cloud-aerosol interactions are on the bleeding edge of our comprehension of how the climate system works, and it’s a challenge to model what we don’t understand,” Meehl said. “These modelers are pushing the boundaries of human understanding, and I am hopeful that this uncertainty will motivate new science.”"

Can you really model something that you don't understand? Yes, you can. But it will definitely be GIGO.

https://advances.sciencemag.org/content/6/26/eaba1981
DOI: 10.1126/sciadv.aba1981

https://news.ucar.edu/132741/increased-warming-latest-generation-climate-models-likely-caused-clouds

41

The problem in the statement above is the word "actual". What is actual?

From the same climate-lab-book page link provided (so clear and obvious that it would be hard to miss. Surprising that it was not mentioned when presenting the evidence):
 
"The simulation data uses spatially complete coverage of surface air temperature whereas the observations use a spatially incomplete mix of air temperatures over land and sea surface temperatures over the ocean. It is expected that this factor alone would cause the observations to show smaller trends than the simulations."

How well do the various models perform if the above factor was applied to observational temperature or use of a more spatially complete data set? e,g. Cowtan and Way (although not perfect widely accepted to be a more accurate record of global temperature increase. Remember - here we're trying to evaluate the accuracy of the models over a relatively short time period (not track global temperatures over a long time period).

Good question!
Moyhu has a nice portal where you can follow various temperature data. It's updated each day.
I plotted six series with land and ocean temps in the attached chart.
Cowtan and Way - dark green
HadCrut - red
GISS - light brown
NOAA - dark brown
BEST - light green
Temp LS Mesh - lila

CW updating is lagging.
All series are showing the same development, with small variations.
To answer your question, no, it wouldn't change the evaluation. Models are running hot irrespective of which temperature data you use.

https://moyhu.blogspot.com/p/latest-ice-and-temperature-data.html

Here is a description of the method for creating Temp LS Mesh, which is a similar attempt to CW to create more spatially complete data by applying statistical methods.

https://moyhu.blogspot.com/2019/10/new-femloess-method-of-integrating.html
https://moyhu.blogspot.com/p/a-guide-to-global-temperature-program.html

42
...

Edit: Also, I note that if AR6 does decide to us weighting factors on ECS projections then they should also downweight the Russian (INM CM4/5) projection of ECS.

INM CM4 and CM5 models are among the ones that track actual temperature developments best. So might be a good idea to keep them - maybe they are the ones that will be demonstrated to have gotten the hydro cycle, as well as the cloud feedback right?
In the first attached 'spaghetti' chart, the INM CM4 is one of the blue ones near the bottom of the spaghetti bowl. Rather close to the actual HadCrut temperatures compared to many high-flying models.
In the second attached chart models are compared in terms of contributions to ECS from different factors.
In the third attached chart models are compared in terms of cloud feedback contributions.

The high-flying models have more to prove in terms of tracking actual temperatures, than their more realistic competitors. So what's the argument, ASLR, why should they be "downweighted", as you propose? Because they don't err on the side of maximum ECS drama?

https://www.climate-lab-book.ac.uk/comparing-cmip5-observations/
https://link.springer.com/article/10.1134/S000143381004002X

43
...
I believe that such evidence indicates that in coming decades we can expect more ice-climate feedback mechanisms than assumed in any CMIP6 model (including in E3SM1).

Ad hoc calvings is a natural phenomenon. It's also snowing a lot over Greenland and the surface mass balance goes up with maybe 600 gigatonnes each winter season.
Espen estimates this calving to be around 200 sq.km. How many tonnes might such a berg be? 1 gigaton? 10 gigatonnes? In any case, it's a rather negligible event in the bigger picture.

Such regular calvings are just part of the natural seasonal variations and no evidence of any drama in terms of "more ice-climate feedback mechanisms than assumed in any CMIP6 model (including in E3SM1)"

44
Science / Re: 2020 Mauna Loa CO2 levels
« on: June 21, 2020, 04:23:08 AM »
1. Clearly, we are not having exponential growth anymore, we're on a linear growth path.
I do not agree. The rates are slightly increasing. The later you look the steeper is the slope.

I averaged 100-month increase rates of Mauna Loa CO2:

1959-1967: + 0.77 ppm/year
1967-1975: + 1.10 ppm/year
1975-1984: + 1.50 ppm/year
1984-1992: + 1.52 ppm/year
1992-2000: + 1.59 ppm/year
2000-2009: + 1.99 ppm/year
2009-2017: + 2.34 ppm/year
2012-2020: + 2.48 ppm/year

These data are not compatible with "linear growth path".

See also the annual increase (raw data) in the attached graph. y-axis: increase in ppm/year

True, but I was looking at Wolfie's detrended /ENSO scrubbed data, and they do show that we have an almost constant growth rate:
2011-2018  2.39
2013-2020  2.40

This would be significant, if correct :)

After all, we do expect CO2 to grow exponentially if temperatures are to rise linearly, as there is a logarithmic relationship between radiative forcing (which is directly proportional to the change in surface temperature at equilibrium) and the atmospheric CO2 increase.
This logarithmic relationship means that each doubling of atmospheric CO2 will cause the same amount of warming at the Earth's surface.
Thus, a linear increase in CO2 means we will have the inverse relationship. In the graph, temperatures will increase, but with decreasing amounts. (the green curve instead of the black one)

45
Science / Re: Magnitude of future warming
« on: June 19, 2020, 08:52:54 AM »
...
One could look towards data we believe is reasonably accurate rather than relying on that we know is not.

Radiosonds have their problems, but since 1980 or so satellite data is presumably used.
We have the AQUA satellite with its Atmospheric Infrared Sounder (AIRS), and the Aura satellite, e.g.

According to NASA research, the satellite data shows less of an increase in humidity in the stratosphere, than models assume:
"Models that include water vapor feedback with constant relative humidity predict the Earth's surface will warm nearly twice as much over the next 100 years as models that contain no water vapor feedback.
Using the UARS /satellite/ data to actually quantify both specific humidity and relative humidity, the researchers found, while water vapor does increase with temperature in the upper troposphere, the feedback effect is not as strong as models have predicted. "The increases in water vapor with warmer temperatures are not large enough to maintain a constant relative humidity,""

This is what is shown in the charts in my post above.
https://forum.arctic-sea-ice.net/index.php/topic,2715.msg268929.html#msg268929
Relative humidity is consistently down on all altitudes measured.

https://www.nasa.gov/centers/goddard/news/topstory/2004/0315humidity.html

46
Science / Re: Magnitude of future warming
« on: June 19, 2020, 08:20:25 AM »
...

2) The data set you get to play with goes from 1950 - 2020. Over that time frame the CO2 and CH4 effects are only present on the end of the range but not in a way they are detectable in your chosen metrics.

You say that "the CO2 and CH4 effects are only present on the end of the range" /from 1950 - 2020/. You must be joking!
CO2 increases continously during this period of 70 years, and GMST have a strong positive trend, with some hiatuses. This should be reflected in the humidity levels, as the effect of increasing CO2 is supposed to go hand in hand with an increase in water vapour/humidity:

This is what they say at SkS:
"As water vapour is directly related to temperature, it's also a positive feedback - in fact, the largest positive feedback in the climate system (Soden 2005). As temperature rises, evaporation increases and more water vapour accumulates in the atmosphere. As a greenhouse gas, the water absorbs more heat, further warming the air and causing more evaporation. When CO2 is added to the atmosphere, as a greenhouse gas it has a warming effect. This causes more water to evaporate and warm the air to a higher, stabilized level. So the warming from CO2 has an amplified effect"
https://skepticalscience.com/water-vapor-greenhouse-gas-intermediate.htm

But the data shows no increase of water vapour, measured as specific humidity (or measured as relative humidity) in the LT. Only a small increase of specific humidity at the surface. (There is btw a bunch of interesting comments at SkS as well, e.g. #2 by someone called Victor.)

The research by Seidel and Yang that cloud feedback in the tropics is negative is also troubling, as clouds are the carriers of water vapour.

47
Science / Re: Magnitude of future warming
« on: June 19, 2020, 01:42:49 AM »
Care to prove the keeling curve is now linear?
Or is that just your eyeballs?
...

I'm following Wolfpack's and Stephan's analyses of the CO2 at Mauna Loa, trying to detrend, and scrub the data from ENSO variability.

We clearly SEEM to have a slowdown in growth rate, and are almost on constant growth now.

https://forum.arctic-sea-ice.net/index.php/topic,2983.msg268712.html#msg268712

I have previously made a forecast somewhere on this forum that we will reach peak CO2 already by 2030. I still think it's possible due to the very strong growth of renewables. And certainly helped by corona lockdowns.
I expect to see a fall in the CO2 growth rate within a year.

48
Science / Re: Magnitude of future warming
« on: June 18, 2020, 11:50:06 AM »
In my opinion based on following climate change since the 70s is that ECS, like the uncertainty of the preindustrial baseline, is a tool for obfuscation.

Why the doubling of co2, what is magical about that standard ?
...

Global annual mean CO2 concentration has increased by almost 50% since the start of the Industrial Revolution, from 280 ppm to 420 ppm now.
Doubling of CO2 means another 140 ppm to add. Currently we add maybe 2.2 ppm per year, and it has become a linear growth. So in 50 - 70 years with continued linear growth we will have doubled the CO2. Kind of graspable.

Testing with GCM models for the effects of a doubling of CO2 thus makes a lot of sense, per se.

49
Science / Re: 2020 Mauna Loa CO2 levels
« on: June 17, 2020, 10:45:03 PM »
I made a mistake in my de-trending chart above.  I didn't de-trend ENSO before de-trending Mauna Loa. If you want to de-trend just *anthropogenic* effects you have to make sure ENSO(lagged) integrates to zero. 

I went with multi-line regression.  I have 4 regression lines where ENSO integrates to zero(accounting for 5 month lag). Blending these together you'll notice that anthropogenic changes are only worth about an additional ~0.1 ppm/year by 2020 compared to 2007.

Thanks, Wolfie.
Two musings related to "anthropogenic changes are only worth about an additional ~0.1 ppm/year".

1. Clearly, we are not having exponential growth anymore, we're on a linear growth path.

2. What if ENSO has an anthropogenic component? Frequency, amplitudes, durations...

50
Antarctica / Re: What's new in Antarctica ?
« on: June 17, 2020, 01:35:09 PM »
Pretty cold in the Southern Ocean and over Antarctica now. Anomalies are on rather low levels both long and short term, according to the CFS Reanalyzer.

Pages: [1] 2 3 ... 13