By Bob Irvine
Is it possible that the Earth’s system is strongly buffered with strong positive ice and dust feedbacks prevailing at colder temperatures, and strong negative convection/evaporation feedbacks prevailing in warmer times?
Feedback Factor (FF) is defined as the total temperature change at equilibrium for a given forcing divided by the calculated “no feedback” temperature from that forcing.
The term CO2 will be used here to represent all the non-compressing GHGs. (CO2, MH4, N2O, CFCs, HCFs etc.)
THE ALARMIST POSITION
It is certainly possible that strong positive feedbacks can apply in a world where H2O exists as a vapor in the atmosphere, as well as water and ice.
It is important here that we represent the alarmist position accurately and honestly. Gavin Schmidt, director of GISS, and his predecessor James Hansen have driven the alarmist narrative with regards to climate feedbacks.
Lacis, Schmidt et al. (2010) represents the alarmist narrative.
They base their paper on the following assumption which I accept.
The difference between the nominal global mean surface temperature (TS = 288 K) and the global mean effective temperature (TE = 255 K) is a common measure of the terrestrial greenhouse effect (GT = TS – TE = 33 K). Assuming global energy balance, TE is also the Planck Radiation equivalent of the 240 W/m2 of global mean solar radiation absorbed by Earth.
They then attribute almost all the GH effect (33C) to CO2 with the water vapor component as a feedback only.
“Noncondensing greenhouse gases, which account for 25% of the total terrestrial greenhouse effect, … provide the stable temperature structure that sustains the current levels of atmospheric water vapor and clouds via feedback processes that account for the remaining 75% of the greenhouse effect.”
A Feedback Factor of about 4 is implied by this 25% figure. They then take the next logical step and attribute nearly all climate change to CO2 with insignificant solar input and internal variability being the only other contributors.
These studies established long ago that water vapor and CO2 are indeed the principal terrestrial GHGs. Now, further consideration shows that CO2 is the one that controls climate change.
To the political mind the proof of all this is quite simple.
This misunderstanding is resolved through simple examination of the terrestrial greenhouse.
The idea of “CO2 as the climate control knob” is then reinforced by removing all CO2 from the 1980 atmosphere using the climate model, GISS Model E [G. A. Schmidt et al., J. Clim. 19, 153 (2006)]. The resulting enormous temperature drop after feedbacks is summarised below in Lacis, Schmidt, et al. 2010.
The scope of the climate impact becomes apparent in just 10 years. During the first year alone, global mean surface temperature falls by 4.6°C. After 50 years, the global temperature stands at –21°C, a decrease of 34.8°C. Atmospheric water vapor is at ~10% of the control climate value (22.6 to 2.2 mm). Global cloud cover increases from its 58% control value to more than 75%, and the global sea ice fraction goes from 4.6% to 46.7%, causing the planetary albedo of Earth to also increase from ~29% to 41.8%. This has the effect of reducing the absorbed solar energy to further exacerbate the global cooling.
Some water vapor is then attributed to the sun (10%), can you believe, leaving an approximate feedback factor for CO2 forcing of 3.3. The official figure that has not changed to this day.
Schmidt then implies that feedbacks to incremental temperature change during the Last Glacial Maxima apply to the warmer interglacial world we inhabit today.
http://www.realclimate.org/index.php/archives/2007/08/the-co2-problem-in-6-easy-steps/#more-462
“…the last glacial period is a good example of a large forcing (~7 W/m2 from ice sheets, greenhouse gases, dust and vegetation) giving a large temperature response (~5 ºC) and implying a sensitivity of about 3ºC (with substantial error bars). More formally, you can combine this estimate with others taken from the 20th century, the response to volcanoes, the last millennium, remote sensing etc. to get pretty good constraints on what the number should be. This was done by Annan and Hargreaves (2006), and they come up with, you guessed it, 3ºC.”
In this way a narrative is established. CO2 is promoted as the control knob of the climate with incremental changes in solar activity reduced to insignificant.
THE SCEPTICS POSITION
The alarmist narrative is too simple, and all the climate models are running hot. As a result, all the predictions based on these models have failed (see Appendix “A”.). There are some areas of immediate concern with the Lacis, Schmidt 2010, approach.
In their modelled experiment sea ice fraction goes from 4.6% to 46.7% “causing the planetary albedo of Earth to also increase from ~29% to 41.8%.”. 12.8% (41.8 – 29) of 340 w/m2 is a massive ice feedback of 43.5 w/m2 which dwarfs the 25 w/m2 for all the non-condensing GHGs.
In the modern world, ice has retreated to the colder poles where the suns angle is oblique. Ice feedbacks today are an order of magnitude weaker than found in the model experiment. If we take account of this, the feedback factor must be reduced significantly in a warmer world.
At the other extreme, a warmer world will drive greater convection, a huge negative feedback. Convection is allowed for in the models but is extremely complex. If the models have it wrong in any way, feedback factor could be significantly impacted. Certainly, this large negative feedback will be stronger in a warmer world.
Lacis, Schmidt 2010, specifically rule out any feedbacks that are unique to solar activity. These could include, cosmic ray effects, jet stream changes, and any number of others. The oceans temperature profile is overwhelmingly driven by solar forcing. Is it possible that a warmer ocean reacts more vigorously to solar change than a colder ocean?
As an illustration Figure 1 shows a possible relationship between CO2 and feedback factor (FF). There are of course enormous error bars involved here so this should only be treated as “for discussion only”.
Figure 1. A possible comparison between CO2 concentration and Feedback Factor (FF). The low modern feedback factor reflects my own prejudices. The other two control points are at zero CO2 ppm (Lacis 2010, found a FF of 4 at -21C global temps for zero CO2 taken from a 1980 atmosphere), and at 100 ppm (Annan 2006, found a FF of 2.7 at 9C global temps which could apply with 100 ppm CO2).
APPENDIX “A”.
CLIMATE MODEL FAILURE
These exaggerated positive feedbacks may not apply in a warmer interglacial and may have caused all the IPCCs forecasts to fail within 10 years of their announcement. Their forecasts have consistently failed since the first one was attempted by James Hansen in 1988. See Figure 2 below. The most recent of these is the predicted temperature increase in the Fourth Assessment Report 2007. See Figure 9 below.
Figure 2. Hansen’s failed predictions from 1988. CO2 concentrations have actually grown faster than scenario “A”. The black and red lines are the heavily adjusted surface record (Always adding extra warming on average).
Current CO2 concentrations are increasing at a rate similar to the A1T and B2 scenarios in the 4AR IPCC report copied here. I have used them for this reason.
https://www.ipcc.ch/publications_and_data/ar4/wg1/en/spmsspm-projections-of.html
These scenarios result in between 750ppm and 800 ppm CO2 concentration in the year 2100. Read the above link to get a sense of the IPCCs processes and their position on future warming.
Figure 3, The IPCC forecast from 2007 compared to actual temperatures. The red line is the Hadcrut4 temperature series. It is similar to the NASA GISS series and has been adjusted many times. The blue line is the more accurate Mid Troposphere Satellite Temperature data. The yellow line is the NAS data from 1975. NAS was the precursor of NASA and was considered state of the art in 1975. The 2007 model predictions (Grey Line) are already 0.7C warmer than the measured data in 2021.
Five-year averaged values of annual mean (1979-2015) global bulk (termed “midtropospheric” or “MT”) temperature as depicted by the average of 102 IPCC CMIP5 climate models (red), the average of 3 satellite datasets (green – UAH, RSS, NOAA) and 4 balloon datasets (blue, NOAA, UKMet, RICH, RAOBCORE).
Figure 4. The graph presented to the US House Committee on Science, Space and Technology by John Christy in 2016. According to the GHG theory, Mid-Tropospheric temperature rise is the fingerprint of GHG warming. It is obvious that the models with their high feedbacks produce more warming in this area than do our most accurate temperature measure, the satellites. The balloon data also agrees well with the satellites and is well below the models.
Is zero non-linear?
Touché.
I guess it is open ended…
A closed circle, IMHO.
Example of Zero CO2 feedback, whereby the house is heated with dry cow-pat. Grant applied for more research to the UK’s Department of Energy & Climate Change.
Perfectly nailed it there Vuk, in every respect
You even got the cow right. i.e Dairy cow – she looks like a British Friesian too, not one of those poor depleted Holsteins
Because, The Dairy Cow is The Most Efficient food-producing ‘thing’ there is. Human Food i.e. Saturated Fat
She also makes ‘soil food’
As she goes. she carefully selects the sugar factories (leaves) off the grass plants leaving the stalks behind. Which she then, with carefully adapted feet, mashes into the ground, storing carbon, plant nutrients and water. Those thing combine to control Climate.
Her ‘cow-pats’ which you could burn if you so desire, are actually better off left in the field helping with the business of Soil Food.
(Burning it loses the water-soluble Nitrogen – show her some respect coz she went to a lot of effort fixing that Nitrogen)
She only exists on perennially green fields, widely recognised for having much higher albedo than ploughed fields, paddy fields, burning/burned forest and sprawling mega-metropoli – again having a moderating effect on – Climate
Now and again she will make ‘one-too-many’ male offspring – chock full of protein, vitamins and trace element minerals.
Thus achieving a near perfect Human Diet of 80% fat and 20% protein – absolutely perfect for the human soul as well as its body.
Cows are also very good listeners and in their own way, reciprocate.
They know how Climate works, walk and talk with them and they will tell you.
(sigh. I feel really sad now, I do miss my cows)
well said Peta .. and if I may add an excellent source of Calcium that every ‘greeny’ drinking soya or almond liquid as a poor substitute is desperately short of.
(p.s. illustration is courtesy of the google images)
Bossy was one of our Jersey cows when I was a young boy. We spent many pleasant S. CA Spring, Fall and Winter hours snuggling in the pasture. She would wrap her neck around me and keep me toasty warm. As an adult, I wish I could recapture those feelings.
They are making a Michael Mann plush toy but word is they had to reduce the real life proportions as it was too….plush
Mike needs a diet I think
Rural African communities are in full compliance with this cartoon.
So they are applying climate feedbacks that cause the end of an ice age to an interglacial climate?
Did I get that right?
Yes, they fail to understand that the ice melt that caused what they mis-characterized as positive feedback has already melted just about all of the ice it can melt (it keeps coming back in the winter). If all the ice on Earth was permanently gone, the increase in forcing arising from a lower albedo and distributed across the planet is still not be enough to cause the magic 3C claimed to be caused by CO2 emissions.
First five words are all you needed.
Where are you seeing that the ice that has already melted is all of it that can melt?
Antarctica will only melt in the event of an impact event or large volcanic event in which case we will have much bigger problems. Much of it is at an elevation where ice and snow can be found even at the equator and it’s yearly average temperature is far below freezing. Greenland is also relatively safe as it’s average interior temperature is low and it’s altitude is relatively high. Most of the rest of the planets ice and snow is seasonal. And then there’s the math.
The average fraction of the planet covered by ice is about 13%. The average difference in reflectivity between ice and the surface is the difference between about 40% and 12% and ice (which gets dirty quickly) is about as reflective as clouds. About 2/3 of the surface is covered by clouds, so if 13% of the planet had its reflectivity decreased from 40% to 12% and for the average solar input of 341 W/m^2, the increase in average solar input to the planet is 1/3 of 13% of 28% of 341 W/m^2 = 4.1 W/m^2. For doubling CO2 to increase the surface temperature by 3C, surface emissions would need to increase by about 12 W/m^2 which is said to be caused by 3.7 W/m^2 of CO2 ‘forcing’. The forcing offsets 3.7 of the emissions increase, while the remaining 8.3 W/m^2 of replacement power still needs to be identified. About 4.1 would arise from an albedo change if all the ice melted, so where are the other 4.2 coming from, assuming that all the ice had already melted?
Albedo should only be used with respect to diffuse retro-reflectance such as with clouds, suspended plankton/sediment, and vegetation. It is inappropriate for the 71% of the Earth covered by water.
Albedo is another of those terms appropriated by climatology that is akin to “Greenhouse Effect” and “Ocean Acidification.” It is misleading and inaccurate. It is a lower-bound on the total reflectivity.
The net specular reflection of sea water near the poles is primarily affected by waves. With whitecaps formed, the reflectivity will be increased at high sun angles, and decreased at low sun angles.
Consider reflectivity instead. From space, the intricate details of what contributes to albedo are irrelevant and only the final AVERAGE reflectivity matters.
Today, the planet reflects about 30% of what it receives from the Sun. Oceans reflect about 8%, while ice free land reflects double at about 16% and 13% of the average surface is ice. Clouds and surface ice reflect about 40%. For 70% of the surface covered by oceans, the average surface reflectivity is about (16*.87 + 40*.13)*.3 + (8*.87+40*.13)*.7 = 13.5%. For 2/3 of the planet covered by clouds, the average reflectivity is 40*.67 + 13.5*.33 = 31% which is close enough to the average 30% or so given the rough nature of this calculation..
Yes, those are the officially accepted values. However, I’ve made the argument that nadir-viewing satellites underestimate the reflectivity of most things, water in particular. Even CERES is blind to light reflected away from the sun at the high angles of incidence where water reflectivity is changing rapidly.
Fundamentally, my point is that only considering hemispherical scattering from diffuse reflectors, which is what most satellite can see, gives an underestimate of the total reflectivity.
A rose is just as sweet by any other name. Whatever you call it, if it is retro-reflectance that is being measured, such as with the moon, then it misses the forward reflectance of specular reflectors such as water. Even snow has a strong forward lobe in the BRDF because the flakes of snow tend to lie preferentially in sub-horizontal orientations.
Yes, scattering happens and a satellite sensor over one spot on the planet will not see everything scattered from below, but will see power scattered from elsewhere. Polar orbiters cover the entire surface, so this effect is basically averaged away.
It’s disturbing how so many on both sides of the climate issue get sidetracked by minutia, much of it about speculative causation, that the law of big numbers and the law of averages makes irrelevant.
For example, the many millions and perhaps billions of remotely sensed measurements of the ratio between the Stefan-Boltzmann emissions of the surface and the radiant emissions at TOA converges to one and only one ratio (1.62) and the law of large numbers tells us that this is the true average of this ratio and is the only legitimate measurement of the sensitivity of the surface temperature (by proxy of SB emissions) to forcing expressed in W/m^2.
I must disagree Clyde. Albedo is a primary variable in the planetary heat balance.
https://wattsupwiththat.com/2016/09/12/why-albedo-is-the-wrong-measure-of-reflectivity-for-modeling-climate/
written by you…..still disagree….
Yes it is written by me. I wouldn’t attempt to speak for someone else.
Can you point to anything that that is wrong? So far, all you have offered is your opinion without any facts, logic, or citations.
What figure are you using for the other feedbacks like water vapor?
Feedback is irrelevant. The analysis applied by Schlesinger to justify the concept was incorrectly applied by 1) ignoring the requirement for strict linearity, 2) ignoring the requirement for an ‘active’ system (i.e. one that has an implicit, internal source of energy) and 3) confusing the feedback fraction (the fraction of output returned to the input) with the feedback factor which is the feedback fraction times the open loop gain.
The last error was a math trick that cancelled out the non linear relationship between emissions and temperature providing false legitimacy that linear feedback analysis can be applied to a non linear relationship.
You were trying to balance the 12 W/m2 of extra emission. The 3C of warming includes feedbacks. Did you include the extra DWIR from water vapor?
BTW…I actually get a 16 W/m2 increase with a 3C increase.
The 12 W/m2 are in excess of the 4 W/m2 of forcing claimed to arise from doubling CO2. So in other words, the presumed positive feedback must create 3 times more energy than the forcing itself. Not only is this is a clear and unambiguous violation of COE, its application as a climate model is representative of an unstable system.
There’s no ‘extra’ DIR from water vapor. CO2, CH4 and Ozone are mostly static absorbers. Water vapor works in conjunction with clouds to chaotically vary the equivalent emissivity of the planet, relative to the surface temperature, between about 0.75 under clear skies and about 0.55 under cloudy skies. Given 2/3 coverage by clouds, the average becomes about 0.62 which is confirmed by data as the ratio of the average surface emissions at about 390 W/m2 @ 288K and the planets emissions of about 239 W/m2 @ 255K.
It turns out that this ratio, e, is also predictable from the math as a root of the polynomial (1/e)^2 – (1/e) + 1 = 0 which arises from the energy optimum self organization of clouds emerging from a chaotically variable ratio between the radiant surface emissions and the radiant emissions at TOA.
Fear spreads up on Capitol Hill
?w=660
The Climate change will break their will.
AOC: In Ten years
our world disappears!
She acts as a New Green Deal shill.
Quote from Alexandria Occasio-Cortez in January 2019: “Millennials and Gen Z and all these folks that come after us are looking up, and we’re like, ‘The world is going to end in 12 years if we don’t address climate change, and your biggest issue is how are we gonna pay for it?’ ” she said.
I beg to differ.
We live in only one world. As a concerned citizen I realize we have immense environmental challenges before us, with water pollution; from plastics in the ocean, excess fertilizer in the rivers, poison from all kinds of chemicals, including antibiotics, birth control and other medicines flushed down the toilet after going through our bodies, animals fed antibiotics, pest control, weed control and so on. Increasing CO2 is not one of the problems, it will in fact help with erosion control, and allow us to feed more people on less agricultural land with proper management, and require less fertilizer and water to do so. In fact, proper water management is a larger problem, with some rivers no longer even reaching the ocean. All water is already spoken for, especially in the 10 to 40 degrees latitude, where most people live.
Allow me to be somewhat technical and give the background to why I know we will never experience the thermal runaway they are so afraid of.
Many years ago I worked at Hewlett Packard on an Atomic Absorption Detector. It was a huge technical success but a commercial failure, as it was too expensive to use for routine applications. However it found a niche and became the detector of choice when dismantling the huge nerve gas stockpiles remaining from the cold war. I was charged with doing the spectrum analysis and produce the final data from the elements. One day two salesmen came and tried to sell us a patented device that could identify up to 21 different elements with one analysis. They had a detector that divided the visual band into 21 parts, and bingo, with proper, not yet “fully developed” software you could now analyze up to 21 elements with one gas chromath analysis. What could be better? We could only analyze correctly four or five elements simultaneously. It turns out the elements are absorbing in the same wavelength bands, scientifically speaking they are not orthogonal, so software massaging can only go so far. It turned out that the promised new detector was inferior to what we already had and could only quantify three or 4 elements at the most.
In the atmosphere the two most important greenhouse gases are water vapor and CO2 with methane a distant third. Water vapor is much more of a greenhouse gas everywhere except near the tropopause high above the high clouds and near the poles when the temperature is below 0 F, way below freezing. A chart shows the relationship between CO2 and water vapor:
Source: http://notrickszone.com/2017/07/31/new-paper-co2-has-negligible-influence-on-earths-temperature/
Even in Barrow, Alaska water vapor is the dominant greenhouse gas. Only at the South Pole (And North Pole) does CO2 dominate (but only in the winter).
All Climate models take this into account, and that is why they all predict that the major temperature increase will occur in the polar regions with melting icecaps and other dire consequences. But they also predict a uniform temperature rise from the increased forcing from CO2 and the additional water vapor resulting from the increased temperature.
This is wrong on two accounts. First, CO2 and H2O gas are nor orthogonal, that means they both absorb in the same frequency bands. There are three bands where CO2 absorbs more than H2O in the far infrared band, but other than that H2O is the main absorber. If H2O is 80 times as common as CO2 as it is around the equator, water vapor is still the dominant absorber, and the amount of CO2 is irrelevant.
Secondly gases cannot absorb more than 100% of the energy available in any given energy wavelength! So if H2O did absorb 80% of the energy and CO2 absorbed 50%, the sum is not 130%, only 90%. (0.8 + 0.5×0,2 or 0.5 + 0.8×0.5). In this example CO2 only adds one quarter of what the models predict.
How do I know this is true? Lucky for us we can measure what increasing CO2 in the atmosphere has already accomplished. For a model to have credibility it must be tested with measurements, and pass the test. There is important evidence suggesting the basic story is wrong. All greenhouse gases work by affecting the lapse rate in the tropics. They thus create a “hot spot” in the tropical troposphere. The theorized “hot spot” is shown in the early IPCC publications. (Fig A)
Fig. B shows observations. The hotspot is not there. If the hotspot is not there, the models must be wrong. So what is wrong with the models? This was reported in 2008 and the models still assume the additive nature of greenhouse gases, even to the point when more than 100% of the energy in a given band is absorbed.
How about Methane? Do not worry, it absorbs nearly exclusively in the same bands as water vapor and has no measurable influence on the climate.
But it will get warmer at the poles. That will cause melting of the ice-caps? Not so fast. When temperature rises the atmosphere can hold more water vapor, so it will snow more at higher latitudes. While winter temperatures will be higher with more snowfall, this will lower the summer temperatures until the extra snow has melted. And that is what is happening in the Arctics
As we can see from this picture, the winters were about 5 degrees warmer, but starting from late May through early August temperatures were lower. It takes time to melt all the extra snow that fell because of the less cold air, able to contain more water vapor.
These are my suggestions
with pictures: https://lenbilen.com/2021/02/14/clouds-water-vapor-and-co2-why-nearly-all-climate-models-fail-and-a-limerick/
Just don’t allow CO2 to drop below about 400 ppm.
I believe installed that Kwajalein sensor group in ’98.
There is a spelling error early on—non-compressing for non-condensing.
Mann 2010 says CO2 is the dial eh?
NASA pulled this webpage in, I gather, 2011., But left the link to it live. They were STILL saying it’s the sun drives climate just 10 years ago.
https://web.archive.org/web/20100416015231/https://science.nasa.gov/earth-science/big-questions/what-are-the-primary-causes-of-the-earth-system-variability/
“What are the primary forcings of the Earth system?The Sun is the primary forcing of Earth’s climate system. Sunlight warms our world. Sunlight drives atmospheric and oceanic circulation patterns. Sunlight powers the process of photosynthesis that plants need to grow. Sunlight causes convection which carries warmth and water vapor up into the sky where clouds form and bring rain. In short, the Sun drives almost every aspect of our world’s climate system and makes possible life as we know it.”
Do Schmidt, Lacis, Hansen, Mann, etc.(and the other alarmists) only deny the Milankovitch effects as the “primary driver” of the glaciation cycles? Or are they even more foolish and claim Milankovitich cycles – even in their more extreme combinations — as mostly irrelevant to the glaciation cycles ? I would like to know.
At least NASA.gov still has this page.
https://climate.nasa.gov/news/2948/milankovitch-orbital-cycles-and-their-role-in-earths-climate/
I’ve not seen Schmidt, Hansen, or Mann challenge the hypothesis that orbital perturbations are a contributing factor to glacial cycles of the Quaternary Period. If anyone knows of publications in this regard. I too would be interested in reviewing those materials if they exist.
I always ask myself, when a graph is truncated (eg GISS, Hadcrut at 2011 in the Hansen comparison) when the censored data is freely available, WHY?
There goes the ‘all models run hot claim’. Sorry ’bout that. Is this honest?
Yeah, when you include the missing data you’ll see that the temperature is pretty close to scenario B. Scenario B was Hansen’s best guess at human behavior. It turns out that emission reductions (like from the Montreal Protocol) and larger than expected volcanic aerosols means that the real scenario that actually played out was between C and B and that Hansen’s model may actually be underestimating warming if anything. The thing I find most interesting here is that the physics from a 30 year model that is considered primitive by todays standards actually does reasonably well. The takeaway here at least from this single data point may be that science should focus some of its efforts on improving our understanding of human behavior so that the scenarios and inputs fed into the models are more accurate.
Indeed:
Here is Nick Stokes’ graph the last time this place tried to rubbish Hansen’s projections (barely a month ago).
from: https://wattsupwiththat.com/2018/06/30/analysis-of-james-hansens-1988-prediction-of-global-temperatures-for-the-last-30-years/
So Nick Stokes believes we have warmed 1 ºC since 1960. Interesting. HadCRUT4 certainly doesn’t say that.
HADCRUT Linear OLS trend since 1960 0.01467C/year.
Multiply by 60 years = 0.88C
NASA trend = 0.1719C/year x 60 = 1.03C
Pretty much what Nick’s graph shows.
No, no. In Nick’s graph all observations are at 0ºC in 1960, At the end Giss is at +1.2ºC and HadCRUT at +0.85ºC.
In your Wood for Trees graph HadCRUT4 is at +0.63ºC.
In Hansen’s, emissions have followed scenario A where temperatures should be >1.5ºC. Even with less emissions scenario B is 1.2ºC.
Hansen is also hot.
Land ONLY
So the ocean temps have risen even more in order to make the total come out correctly?
Its all fun and games when your trend ends on a Super El Nino. HadCRUT says it hasn’t warmed in 7 years 4 months.
From 1960/01 to 2021/06…
HadCRUTv4 = +0.147 C/decade trend or +0.90C change
HadCRUTv5 = +0.177 C/decade trend or +1.09C change
Except that the trend doesn’t tell you the temperature change that has taken place, but the temperature change that would have taken place if the trend was followed.
HadCRUT4
Temp average for 1960: -0.05ºC
Temp average for last 12 months: +0.63ºC
We are 0.27ºC below trend. That’s because warming is slowing. That’s the problem with trends, they are not the real thing.
Temp increase HadCRUT4: +0.68ºC
Temp increase Hansen A: +1.5ºC
Temp increase Hansen B: +1.1ºC
Hansen is verrry hot.
No, the top (purple) is Cowtan&Way Krig …
https://moyhu.blogspot.com/p/latest-ice-and-temperature-data.html?m=1
And Giss is land only
Hansen says global. Why would Nick use land only? To get a warmer curve?
Last month Stokes stated his belief that the rising CO2 will cause 6°C warming.
Thank you for the citation. However, your graph does not come from my article. How do you respond to my demonstrating that a simple linear extrapolation from Hansen’s own data does a better job than his “primitive” 1988 model?
You haven’t responded to my request for the uncertainty of the slope of the lapse rate for Death Valley for 1913.
Why leave out the satellite data?
When and where did those “larger than expected volcanic aerosols” take place? The major reason that Hansen’s Scenario C takes a pronounced downturn about 2005 was that, without justification, he assumed two significant volcanic eruptions that did not take place at the dates assumed. Do you have evidence that the equivalent took place, but at different dates? Does the temperature record reflect post-2005 reductions in temperature? Mt. Pinatubo had a significant eruption in 1991; however, the temperature effects only lasted about two years, which is typical.
Verneir et al. 2011. The volcanic eruptions contributing stratospheric aerosols were Nevado del Ruiz (Ne), Augustine (Au), Chikurachki (Ch), Kliuchevskoi (Kl), Kelut (Ke), Pinatubo (Pi), Cerro Hudson (Ce), Spur (Sp), Lascar (La), Rabaul (Ra), Ulawun (Ul), Shiveluch (Sh), Ruang (Ru), Reventador (Re), Manam (Ma), Soufrière Hills (So), Tavurvur (Ta), Okmok (Ok), Kasatochi (Ka), Victoria (Vi – forest fires with stratospheric aerosol injection), Sarychev (Sa), Merapi (Me), and Nabro (Na). Refer to figure 8.13 from IPCC AR5 WG1 for an overlay of these eruptions on a graph of aerosol optical depths.
Note that on pg. 9345 of Hansen 1988 that scenarios B and C include hypothetical eruptions of only two VEI 5 eruptions (one in 1995 and one in 2015). Pinatubo alone was a VEI 6 that lofted 20 MtSO2 into the atmosphere generated AODs of > 0.1.There were 2 other VEI 5 eruptions (another in 1991 and one in 2011) and numerous VEI 4 eruptions plus one large wildfire release that occurred during this period as well providing elevated AODs particularly from 2005 to 2011 that were not included in scenarios B and C.
Basically, I only see one significant event (1991) since Hansen made his forecast.
As to ““larger than expected volcanic aerosols,” Hansen apparently thought that large eruptions should be twice as frequent as what have occurred. He depended on that, and they didn’t happen.
Isn’t it the other way around? Scenario B and C included only two VEI-5 eruptions. In reality there was 1 VEI-6, 2 VEI-5, and several other minor aerosol producers.
Anyway, one thing we can agree on is that none of Hansen’s scenarios including B, which he felt was most plausible, did not adequately replicate the scenario that actually played out primarily because of differences in assumed volcanic activity and human emissions versus what actually happened.
“science should focus some of its efforts on improving our understanding of human behavior”
Been done –
“Memoirs of Extraordinary Popular Delusions and the Madness of Crowds”
Charles Mackay
That book looks interesting. I put it in my reading list.
I should clarify that my statement was focused mainly on human behavior as it relates to GHG and aerosol emissions.
RE: Figure 4.
If this graph were submitted by an undergraduate it would be rejected.
Which Scenario is being plotted?
Where are the measures of structural uncertainty in the satellite data and the spreads in the models runs (aka error bars)
Why was 1979 chosen for the baseline, was it because this was a local maximum in the observations?
What smoothing was applied?
Actually we can guess the answer to all these questions: wherever a choice was made, the choice that made the models look as bad as possible was selected.
Make different choices and you get something like this
https://www.realclimate.org/index.php/archives/2016/05/comparing-models-to-the-satellite-datasets/
This video documents, err, the “choices” made to arrive at that graph…..
https://m.youtube.com/watch?v=qpSEXCQ9U6c
I knew it was dishonest, I did not appreciate the depth of the dishonesty.
That this gets uncritically parrotted here is appalling.
Right now the 13-month average HadCRUT4 is outside the 95% range of CMIP5 42 models, so I would say CMIP5 models run quite hot, and CMIP6 models are going to run even hotter.
There is no question about that. We were promised more warming than we’ve got. Where is our promised warming? We’ve paid for it.
Source? Only that is quite a change since May.
https://www.climate-lab-book.ac.uk/comparing-cmip5-observations/
HadCRUT4 and KNMI explorer.
Looks to me that Ed Hawkins has mixed a lot of observations and scenarios to hide the truth. To begin, it is impossible that GISS and HadCRUT4 show the same warming. Go to Woodfortrees and check it.
A simple look to CMIP5 RCP4.5 mean and HadCRUT4, both with a 13-month centered moving average shows the growing and important disparity.
Warmists can’t be trusted. One has to go to the data and check.
There’s no need to be offensive. Hawkins simply took a figure from the IPCC AR5 and updated it, the methodological choices were not his.
Why have you singled out RCP4.5? The associated temperature change by 2100 is 2.5-3C. Are you saying this is realistic?
Here’s his HADCRUT only plot, his model curve is a lot cooler than yours in recent times. I am sure there is a reasonable explanation.
Because our emissions are closer to RCP4.5 so far than to any other scenario. The warming from RCP4.5 in CMIP5 is obviously not realistic.
This is how I see the situation. Some more warming should take us to +1.5ºC by 2050-60. CO2 levels should not get above 500ppm. Serious cooling starts around 2200-2300.
Your plot is CMIP5 with a different baseline, not 1961-1990, but 1986-2005, only 20 years.
AR5 arbitrarily adjusted projected 2035 temperatures downward because CMIP5 models were running way hot. All you are showing is it takes a Super El Nino to bring observations above the bottom of the downward adjusted CliSciFi projections.
Do you trust authors who hide data? That would include the OP 😉
And the “hide the decline” gang.
It takes a Super El Nino to get the black line barley up into the fog.
Don’t waste barley on such things. It should be malted and mixed with hops.
🤪
A LOT!
So it’s got warmer.
Good.
Cold kills.
Yes
Discussion around here the other day was the good old days of lower CO2, I found this link to stories from the area I grew up in the canadian prairies.
Takes a special kind of intellect to wish to return to that assuming we have any control at all.
https://www.sasktoday.ca/north/local-news/tales-of-a-snow-plow-operator-4040373
Because the study was done at a time when 2011 was current data. The graphs were extended later on with current data and showed a continuing and growing deviation from observations. Post-Super El Nino temperatures are going down and HadCRUT4 zero-trend is now 7 years 4 months.
Graphing a short trend ending on a Super El Nino indicates a desire to deceive, not inform.
According to “Atmospheres” by R.M. Goody and The Greenhouse Effect on Earth:
“with an…application of the radiative transfer theory…and a calculation of the profile of temperature as a function of altitude….a reasonable model consists of two layers, with the top layer entered at a height of about 3km and the bottom layer centred at a height of about 0.5km..if we remember that water vapour is the principal absorbing gas in the Earth’s atmosphere.
The top layer is equal to the effective temperature of minus 20ºC.(3km Alt.)
For the bottom layer, the fourth power of the temperature is equal to twice the fourth power of the effective temperature because the the bottom layer is the second layer from the top. We find that the temperature of the bottom layer is 24ºC (0.5km)
Since these two data points are not enough to draw a profile, we will compute one further point, namely, the lower limit to the temperature at very great heights. The temperature of the thin layer is called the skin temperature.. at radiative equilibrium.. is minus 61ºC.
Our theoretical model will be complete once we have calculated the ground temperature.
The fourth power of the ground temperature is equal to the fourth power of the effective temperature added to the fourth power of the temperature of the bottom layer of the atmosphere.
We find a value for the ground temperature of plus 60ºC
We see that the theoretical model is quite successful at altitudes above 10km but that there are substantial deviations throughout the troposphere.
Our theory is inadequate because radiation is not the only process that carries heat upwards from the ground and from the lower levels of the atmosphere.”
90% of long wave from the surface is absorbed in the first 1km.
Likewise 90% of downward long wave from the atmosphere comes from the the first 1km.
80% of which comes from the the first 500m and 33% from the the first 10m.
As actual dry land surface temperatures are pretty close to that 60ºC on a sunny summer day it seems that water vapour’s resistance to radiative cooling of the surface is what stimulates convection over land by increasing the lapse rate to that of instability and for convection to begin to warm up the boundary layer which at night will radiate at that temperature to slow down the radiative cooling of the ground. It is the thermal storage in this layer that provides the “greenhouse effect”. Dry desert air at 5ºC is not enough to stop ice forming at night.
https://www.fieldstudyoftheworld.com/persian-ice-house-how-make-ice-desert/
Only after many dynamic processes is there any radiative equilibrium between incoming solar
and outgoing long wave to space.
This is a good summary of what I have spent the last several months researching. Thank you for the reference book. I see Amazon has a fairly cheap used copy.
Too many folks talk of the surface temperature being generated directly by the sun’s radiation even though they are actually addressing surface AIR temperature near the boundary between land/ocean and the atmosphere.
Thermodynamically, we have a multibody scenario that is complicated by rotation and other effects. This makes it really difficult to simplify into an easy to visualize what is happening. Looking at a “radiation budget” drawing just slays me.
“using the climate model…
… a narrative is established.”
If you don’t know how something works you cannot in all honesty model it with any accuracy. The results are tainted by estimations, assumptions and best guesses. In short, they are wrong. But then, a narrative requires nothing more than a[n emotional] story.
Trying to detrend the AMO with 2.5 turning points in the series to work with is another example of forcing round pegs in square holes to get straight lines. Free the irregular cycles from their regulators!
Yes, of course it is.
Because the dominant store of ocean heat and its transfer by convection to the troposphere control the global climate, and in particular the atmospheric climate and lapse rate, by evaporation and cloud formation. Oceanic evaporation rates increase exponentially with temperature.
Everyone know that. CO2 is not a control. Its an infinitesimal effect amongst dominant causes and effects. Including C)2 ina climate model is like adding an ineffectual insulation product to your windows, or similar.
And the main control and the thermostat maintain equilibrium at whatever it is set to until it runs out of control. The small additional warming effect is not a control. Obs.
The main feedback, the rate of evaporation, increases exponentially with SST, and that is the primary and dominant NEGATIVE FEEDBACK control of surface temperature, by adiabatic convective equilibrium transport to the troposphere, 105W/m^2, which also creates the lapse rate, not GHE BTW, as the basic barometric law tells us.
This also forms clouds at a similarly exponentially increasing rate to reduce surface insolation as the oceans warm, more water vapour = more clouds, while liberating the latent heat in the Troposphere as LWIR to be radiated to space from the Tropopause. Another 50W/m^2 of cloud albedo, probably.
So currently a highly variable negative feedback of 150W/m^2. THat’ll do.
As any fool know. But not climate scientists.
Scientists who study proven meteorological science based on the laws of physics and actual observations, versus creating models they make up to fit the beliefs of false prophets, all know this.
Because getting the weather and aviation parameters correct saves lives, so the science isn’t made up in computers accirding to the simple assertions of the programmers, but extrapolates real physics and observations instead..
But note that the safety net against tipping points during cooling is weaker, because evaporative feedback must reduce exponentially with SST. Worse, any significant area of ocean freezing increases albedo and an ice planet could be the result. I wonder of the submarine volcanic warming of the deep oceans stops this from happening, especially on the SH with such good ocean mixing. See below for the larger effect of volcanoes.
This ice planet tipping point is the most likely in the natural ice age cycles, as they get successively colder while still managing to climb to the tropical 28 degree SST plateau maximum. One day the interglacial may not be back. But we will have relocated by then, and may be debating if the next warming will ever happen?
POINT: The evaporative effect and its cloud consequences, mostly in the tropics, is the well known and dominant control of SST. CO2 never was, its a tiny effect, even the “climate science” says that.Within the noise and observably similar to out last warming this interglacial in range and rate.
The real control is always the oceanic negative feedback established primarily by the heat deposited primarily in the ocean surface by the Sun, that creates and supports the atmosphere and oceans of a frozen rock to start with, and thus creates the lapse rate by the gravitational pressure on the atmosphere the convective effects circulates within. Meteorology 101. Ph=Po e^-(mgh/kT)
Nothing to do with CO2. Not even in the meteorological equations defining this (water vapour is when adjusted for as a non ideal gas)
Dust on the ice surface and ice melting are both strong POSITIVE feedbacks during the early stages of 7Ka interglacial warmings, NOT NEGATIVE, but not driving effects either. Just helpful.
The oceanic control is the dominant control flat lines interglacial warmings at the tropical saturation SST level around 28degC. The tropics then expand North and South, as happened in the Eemian, to evaporate more ocean at 28deg..
Surface volcanoes are not really significant in long term changes, the oceans keep control by lowering SSTs hence surface evaporation and cloud albedo until the aerosols clear. Volcanic heat heat is quickly lost to space through the atmosphere. All back to normal, except for the odd mass extinction of the organic froth on the land surfaces.
BUT beneath the oceans is a very different, and ill considered, story. As regards ice age cycle period changes.
I suggest what delivers the primary and sustained warming over 7Ka at the end of stable glacial cycles is the known and quantified massive increase in underestimated submarine volcanic warming of the oceans at interglacial event time. I suggest this known effect, far bigger thad diverging ridges across the cumulative sea mount population, is triggered by the combined orbital forcing of the MIlankovitch orbital gravitational cycles of 100Ka, 41Ka and 23Ka.
Not the insolation effects, dust, etc..
This control delivers massively increased amounts of heat directly to the oceans in varying quantities, with recorded peaks at the main Milankovitch cycles, through crystallising 1200 deg magma at 1.4×10^9 Joules per tonne. This currently delivers a steady heat flux of 1×10^20Joules pa from 5,000 decent sized volcanoes, which varies substantially at MIlankovitch cycle peaks.
The steady ocean rise despite the wide temperature variability in the proxy record on land suggests this is a highly probable cause. Where else can the heat come from to maintain the telentless rise of the oceans, 130m, when the surface has temporarily returned to glacial temperatures during the NH Dryas?
Dust and melting ice must deliver a helpful start and feedback respectively to an interglacial warming, once the primary causal heat impulse perturbation gets it started, a feedback which also grows during this event.. Again, I don’t see how dust or ice helps to control a cooling, rather the opposite – dust makes SSTs colder, when ocean ice starts to form, that will accelerate cooling, as discussed above.
Also, the Ice age cycle cooling we observe is more classical exponential cooling from the sudden and relatively impulsive heating of an interglacial. The cooling is modified by the 41Ka and 23Ka Milankovitch cycles effects, which also cause powerful but less energetic overall peaks in submarine volcanic emissions, hence oceanic heating. Again, probably concentrated at the surface due to the extreme temperatures involved, which will create strong convection as they occur.. It’s discussed more fully here…. out of time now….
http://dx.doi.org/10.2139/ssrn.3259379
Temperature is a bad measure of heat content. The only correct one is enthalpy. You can have two vessels containing the same number of water molecules at the same temperature with vastly different enthalpy values. Given the amount of water in the system, using temperature is just plain dumb.
There are situations where temperature is a better metric than enthalpy. Wisdom is in knowing when to use the best one. It is dumb to insist that enthalpy is always best.
The feedback analysis applied to the climate system assumes a strictly linear relationship between W/m^2 and temperature. Clearly, W/m^2 depends on T^4, which is an immutable law of physics and is clearly non linear. The idea that feedback analysis applies to the climate is complete BS whose only purpose is to feign an effect large enough to be of concern. It depends on forcing increasing future forcing, which is completely bogus. Feedback does not increase the forcing, but modifies the effect constant forcing will have. This purposeful misrepresentation of feedback analysis by climate science should be criminal given how much waste, fraud and abuse it’s causing as well as it’s detrimental impact on science itself which owing to its success, this political malfeasance has spilled over into other fields, for example, medicine.
This climate feedback crap is so wrong it’s an embarrassment to all legitimate science; moreover, it’s scientific ‘justification’ depends on ignoring the only preconditions for applying feedback analysis and is bolstered with a math trick that replaced the fraction of feedback returned to the input with that fraction times the open loop gain, which is furthermore assumed to have a value of both 1 and an arbitrary value that converts degrees into W/m^2.
The Earth is chaotic, neither a simple scalar nor a stochastic synergy.
Yes. Clouds chaotically vary the ratio between the planets emissions and the surface emissions between about 0.75 (no clouds) and 0.5 (max clouds) chaotically organizing the energy stored by the atmosphere by adjusting it’s transparency. The math is unambiguously clear that the chaotic self organization of the atmosphere’s stored energy arising from chaotically variable clouds will converge this ratio to a constant value of 1/g=0.618023, where g is the converged ratio of sequential members of the Fibonacci series. This is within 1% of the measured value of the average ratio between these two values which can be trivially calculated as the average emissions of the planet (240 W/m^2) divided by the average emissions of the surface at 288K (390W/m^2) where 240/390 = 0.615 .
Chaos is indeed golden.
These exaggerated positive feedbacks may not apply in a…
A limited frame of reference. A novel conception in modern science, where mortal gods and goddesses are known to conjure colorful conceptions throughout time, space, and a plausible beyond.
Obviously the CO2 induced positve feedbacks will be outweighted by emerging negative feedbacks. CO2 has been between 180 ppm and over 2000 ppm without any tipping points reached before. Le Chatelier’s principle is valid for earth as well otherwise life would have ended millions of years ago.
So the question becomes just how stupid and greedy are politicians?
Hmmm….they allow for planetary albedo change with sea ice cover change of 4.6% to 46.7% based on a change of albedo from .1 to .9 as the ocean freezes….yet seem to not mention the 65% cloud cover of the planet already with an albedo of up to 0.9, that renders ice cover at the extreme edges of the Sun’s illuminated area much less effective than equatorial cloud cover as an albedo control mechanism. This is the result of “clouded thinking” from people who believe that clouds with an Albedo of 0.9 blocking Sunlight over an ocean with an Albedo of less than 0.1 has a net feedback of “zero”, which is only true if you assume total cloud SW reflection to outer space is a “planetary” constant…..which you only have to look up at the sky on a clear versus overcast day to realize is…..
The problem is easy to identify. First of all the GHE does not have a magnitude of 33K, regardless of how you define it. Surface emissivity is about 0.91, surface emissions about 355W/m2, and so there is only a GHE of about 115W/m2 (roughly 26K). Then GHGs are overlapped by themselves (f.e. CO2 and vapor) and with clouds. The GHE of CO2 alone would be ~30W/m2 allowing for real surface emissivity (it would be 35W/m2 if the surface was a perfect emitter), of which ~10W/m2 are overlapped with vapor and clouds. Removing CO2 from the atmosphere would thus increase emissions by these 20W/m2.
We have a similar issue when doubling CO2. If the surface was a perfect emitter and there was no overlapping, you would get 3.7W/m2. Due this issue however, you only get a net 2W/m2 of “radiative forcing”, enough to heat the surface by ~0.55K.
The overlapping problem is toxic to all models, because once you allow for it you get no significant ECS. But it is real and can even be found in modtran. Use “US std atmosphere”, add the 2.0km top cloud scenario and you have 242.91W/m2 in emissions TOA. Double CO2, add a temperature offset of 0.78K holding relative humidity constant, and you are back at 242.91W/m2. That is a temperature increase of ONLY(!) 0.78K including vapor feedback. It is because modtran DOES allow for these overlapping issues.
http://climatemodels.uchicago.edu/modtran/
Equally it is pointless to argue a 33K GHE with CO2 and water (vapor and clouds), as clouds obviously will add to the albedo. There it makes a lot more sense to start with the atmosphere effect, that is including the albedo and the GHE of the atmosphere. And that has only a size of about 8K, as explained here..
https://greenhousedefect.com/basic-greenhouse-defects/the-tiny-atmosphere-effect
CO2 has an emissivity of about .0035. How do can we get 30 w/m2?
What?!
mkelly….the lines on those CO2 emissivity charts of Hottel are “atmosphere-cm” and are really for flue-gas of furnaces. And at 400 ppm you haven’t got many atmospheres of partial pressure, but a lot of centimeters of beam length…
Non-linear? As in chaotic? Well, duh.
Chaotic as in non-linear, computationally intractable, and clearly incomplete and likely insufficient characterization of systems and processes.
Yep, climate be chaotic, well, when it is not being cyclical. Ya know? Winter to spring to summer to fall to winter and so on and so forth. Perhaps that is what has these computer modeling pinheads so confused.
Bob, A typo I think. In the third sentence you state: “The term CO2 will be used here to represent all the non-compressing GHGs. (CO2, MH4, N2O, CFCs, HCFs etc.)”
Don’t you mean “non-condensing”?
Back to reading…
Did the author mean to say noncompressing?
Non-condensing would seem to fit the context better.
All gasses are compressible.
The AMO acts as a negative feedback to changes in the solar wind strength via the Northern Annular Mode, and amplified by changes in low cloud cover and water vapour which the changes in sea surface temperature drive.
Stronger solar wind states in the early to mid 1970’s, mid 1980’s, and early 1990’s drove colder AMO anomalies, and weaker solar wind states since 1995 have driven a warmer AMO. The warm AMO phase is also associated with an increase in surface wind speeds over the oceans.
https://www.linkedin.com/pulse/association-between-sunspot-cycles-amo-ulric-lyons/
What’s about noctilucent clouds (NLC) ?
At spaceweather.com it’s often said NLC are increasing because of more H2O in the stratosphere, what mean, there are much more ice crystals in the stratosphere now.
How do they affect earth’ albedo and TSI at TOA ?
So they say : “They then attribute almost all the GH effect (33C) to CO2 with the water vapor component as a feedback only”
So how can they claim H20 feedback is so important when CO2 passed 300pm. Remember that in all of their AGW models, H20 feedback provides between 50% and 80% of the warming they predict. Whether H20 feedback is strong or week, it must apply to ALL scenarios. You cant just reverse the laws of physics as it suits you (unless you are a fraud). The fact that they use very little H20 feedback in the base science is proof of their fraud.
All gases are compressible, did you mean non-condensing?
Is it possible that the Earth’s system is strongly buffered with strong positive ice and dust feedbacks prevailing at colder temperatures, and strong negative convection/evaporation feedbacks prevailing in warmer times?
This proposed set of limiting feedbacks appears to be similar to a proposed model of complex systems exhibiting emergent thermal homeostasis. In this model, where such a system contains both endothermic and exothermic feedbacks, then the system engages these feedbacks spontaneously to exert thermal homeostasis within a narrow temperature band, as an emergent feature:
https://direct.mit.edu/isal/proceedings/alif2016/608/99454
https://ptolemy2.wordpress.com/2021/07/08/emergent-thermal-homeostasis-a-new-paradigm-for-ex-pluribus-unum-climate-stability/
Bartlett and Bullock 2016 – here’s the abstract:
We demonstrate the emergence of spontaneous temperature regulation by the combined action of two sets of dissipative structures. Our model system comprised an incompressible, non-isothermal fluid in which two sets of Gray-Scott reaction diffusion systems were embedded. We show that with a temperature dependent rate constant, self-reproducing spot patterns are extremely sensitive to temperature variations. Furthermore, if only one reaction is exothermic or endothermic while the second reaction has zero enthalpy, the system shows either runaway positive feedback, or the patterns inhibit themselves. However, a symbiotic system, in which one of the two reactions is exothermic and the other is endothermic, shows striking resilience to imposed temperature variations. Not only does the system maintain its emergent patterns, but it is seen to effectively regulate its internal temperature, no matter whether the boundary temperature is warmer or cooler than optimal growth conditions. This thermal homeostasis is a completely emergent feature.
You’re welcome 😉
It half way through 2021, an update of your graphs past 2011 and 2015 is in order.
ECS is the amount of warming per doubling of a greenhouse gas.
Water vapor’s atmospheric concentration is 30,000ppm so it has doubled 16 times, while CO2’s is 415ppm which has doubled about 10 times. (1, 2, 4, 16, 32, 64, 128, etc..)
if the total amount of greenhouse warming is 33K, with 75% caused by water vapor= 24.5K (33K@*.75) and 25% is caused by CO2=8.25K (33K*.25), and given that water vapor has doubled 16 times and CO2 has doubled 10 times, then it would seem logical that water vapor’s ECS is 1.53K (24.5K/16) and CO2’s ECS is 0.825K (8.25K/10), which seems about right.
What am I missing?
Why did you chose to use an “Updated through September 2011” graph for your Figure 2 ?
Real Climate did a “Hansen’s 1988 projections” article (direct link) way back in 2007 which included the following at the end :
The “temperatures” link provides a “digitised” table of numbers for Figure 3(a) of Hansen 1988, with annual averages from 1958 to 2019 for all three scenarios (A, B and C), from which an up-to-date version of the graph is easy enough to generate.
PS : Does anyone have a link to a “digitised” table of numbers for Figure 3(b), the “5-year running means” from 1960 to 2060 (Scenario A) / 2037 (Scenario C) / 2027 (Scenario B) ?
“These scenarios result in between 750ppm and 800 ppm CO2 concentration in the year 2100.”
Awesome, when do we get to 1200ppm?
“Awesome, when do we get to 1200ppm?”
Between 2105 and 2145 (or “Never” …), depending on the scenario.
Is it possible that the Earth’s system is strongly buffered with strong positive ice and dust feedbacks prevailing at colder temperatures, and strong negative convection/evaporation feedbacks prevailing in warmer times?
That’s what I’ve been telling people for years. It’s obvious to anyone who understands how noise and feedbacks interact when they look at the ice-age temperature record.
In order to avoid any confusion, is it possible that Mr. Irvine, when he refers to the feedback factor (f), is actually referring to the total gain (G)? The relationship between these two variables is: G = 1 / (1 – f).
This is how, in his figure 1, while G is around 0.7 for 500 ppmv of CO2, which would lower the temperature after the direct forcing of CO2 by 30%, the feedback factor f would be negative with a value of -0.43.