Guest essay by Mike Jonas
This is how climate works. It’s all about seeing the ocean and atmosphere separately:
- The sun directly warms the ocean.
- Cloud cover changes naturally, affecting the sun’s warming of the ocean.
- Cloud cover changes have only minor effect on the atmosphere.
- Ocean oscillations warm the atmosphere.
- Greenhouse gases (GHGs), including man-made CO2, warm the atmosphere too.
- The atmosphere has little effect on the ocean, except over very long periods.
- If the ocean cools, the atmosphere radiates excess heat to space.
And that’s about it. Well, OK, a few other things do go on in climate, but those are the essentials.
It is generally accepted – incorrectly – that man-made CO2 is the principal force changing Earth’s temperature, and that it will lead to catastrophe (the Catastrophic Anthropogenic Global Warming hypothesis, “CAGW”). The “C” in “CAGW” is very important, because that is the major point of contention. Many scientists and others do think that CO2 warms the planet, but not nearly enough to be catastrophic.This document explains how Earth’s temperature really works, and then goes on to explain how extraordinarily badly the process has been misunderstood and misapplied.
The “mainstream” climate science has been a stuff-up of epic proportions. As with so many major stuff-ups, there was not one error but a sequence of related errors, with hubris and a bit of bad luck thrown in. This is not supposed to happen in science – science is supposed to be self-correcting. Well, mistakes do happen in science, and the self-correction process sometimes takes quite a long time. In the case of climate science, there has been some appallingly shoddy science and bad behaviour, protected by the truly awful process by which science currently operates.
In this series of three articles on This is How Climate Works,
· Part 1 describes how climate works.
· Part 2 explains how mainstream climate science went wrong.
· Part 3 looks at the scientific process.
NB. I do not claim to be the first or only person to put forward any of the ideas in this series of articles. I do hope that I am adding some value by putting it all together.
2. This is How Climate Works
In a recent post, I asked “was ‘the pause’ caused by a change in global cloud cover?“. Some clues to how the climate works were in that post.
Put very simply, clouds control Earth’s temperature and hence its climate, and in the long term the sun controls the clouds.
But there are two different cloud-temperature relationships.
2.1.1 Short term: Temperature -> clouds -> water cycle.
When temperature increases,
· evaporation increases by about 7% per 1 deg C as per the Clausius-Clapeyron relation (“C-C”),
· warm humid air convects up to a cooler layer of the atmosphere where the water vapour condenses to form clouds,
· and then it rains (precipitates).
All of this is in line with the IPCC report. The only major issue that I am aware of is just how much extra precipitation there is when temperature increases, and hence how much “cloud feedback” there is. The IPCC put precipitation increase at 2-3% per 1 deg C increase in temperature. Evidence has been presented that puts it much higher, in line with C-C evaporation. But for this part of the discussion, that doesn’t matter. [I re-visit it later].
Cloud and temperature data shows the formation of clouds soon after a temperature increase, typically 1-2 months after:
Figure 1.1. Temperature and Cloud over Tropics Ocean, with some dates highlighted.
What causes the temperature changes is not specified. For some of the highlighted dates, the cause could have been ENSO. The IPCC argue that this pattern applies for any cause of temperature change, and there seems to be no reason to disagree. Obviously, sometimes “noise” will make it difficult to identify.
2.1.2 Longer term: Cloud -> temperature.
I expect that just about everyone is familiar with some version of the global energy budget
Figure 1.2. Global annual average energy budget, from here).
The item of interest here is the 168 W/m2 of direct solar input that is “Absorbed by Surface”.
Everything to the left of this item in the diagram (Figure 1.2) is reflected to space. Everything to the right of this item is Infra-red (IR) or is converted to IR.
The “168 W/m2” is direct solar radiation, so it contains SW (UV and visible light) as well as IR. Of this direct solar radiation, there is one band of wavelengths, from about 200nm to 1000nm, that is very poorly absorbed by water and by water vapour.
Figure 1.3. Absorption coefficients for water. [From here].
This band of wavelengths passes virtually unscathed (no absorption) through the atmosphere and through the ocean surface, and penetrates many metres into the ocean. I will call this band the ITO (Into The Ocean). The ITO warms the ocean well below the surface with little direct effect on the atmosphere. All other wavelengths cannot penetrate the surface (land or ocean), and enter a rapid cycle of absorption and re-emission until their energy escapes to space, except for a small proportion that manages to enter the ocean, eg. by conduction or as precipitation.
The energy budget as shown in Figure 1.2 is net zero at the surface: 168+324=492 inward, 24+78+390=492 outward. Net zero balance is correct for a stable planet, but there is a big difference in timing between the ITO and the rest. The non-ITO radiation (IR etc) doesn’t hang around anywhere – it spends a very short time being reflected and/or absorbed/re-emitted before nearly all of it escapes to space. But the ITO enters the ocean and its energy can then take a long time to get back up to the surface. That “long time” could be days or months (eg, it might up-well quite quickly), it could be years (eg, waiting to be scooped up in an El Nino), it could be decades (eg, accumulating until an ocean oscillation such as the AMO or PDO brings it to the surface), or it could even be many centuries (eg, taken down into the deep ocean by the THC).
|The ocean acts like a giant heat-pump. Energy from the sun is pumped in short or long bursts by the ocean into the atmosphere. In the short term, or even over decades, the release of energy might bear little relation to its acquisition.|
Those time-scales – days, months, years, decades, centuries – are not “Either-Or” options. The ocean is a large place, and all the timescales apply at some time in some part of the ocean. Similarly, when the energy does reach the surface again, it might do so over a short or long time-scale. In a truly stable planet, the energy budget at the surface would indeed be a net zero, but only over a very long time. On all other timescales, there would be “noise”. And, of course, Earth’s climate isn’t stable over very long time-scales anyway.
There is some debate about whether clouds are net warming or cooling. The generally agreed position is that low clouds are net cooling, while high clouds are net warming, with variations for particular cloud types, etc. But that is all about IR (and EUV) and Earth’s surface (land and ocean) and atmosphere, so it is all irrelevant to this part of the discussion,. It has nothing to do with the ITO. The ITO is affected by the amount of cloud cover – ie. cloud reflectance – and by nothing else of much significance. Cloud height doesn’t matter, only cloud reflectance.With respect to the ITO and the ocean, clouds only cool. More cloud -> cooler, and less cloud -> warmer.
2.2 The IPCC
The IPCC and the models make no allowance for clouds changing independently of temperature. Their view is that clouds are a constant (plus “noise”) until they are affected by temperature. Their view then is that clouds give a positive feedback to temperature. They offer no mechanism, no evidence, and their view is prima facie in the opposite direction to the short term above where temperature increase -> cloud increase.
In the longer term, clouds and temperature do move in opposite directions, as I showed in the ‘Cloudy Question‘ post. ie, temperature and “ClearSky” move in the same direction, and over very large areas of the ocean the cloud cover changes direction several years before temperature does. eg:
Figure 1.5. NH Temperature and ClearSky anomalies, with 11-yr smoothing.
This suggests pretty strongly that cloud cover is in the driving seat, and that the mechanism is as described in 2.1.2 above.
2.3 Sun-Cloud Connection
A long time ago, Henrik Svensmark realised that there was a sun-cloud connection. The sun protects Earth from Galactic Cosmic Rays (GCRs), and GCRs create aerosols which seed clouds. A more active sun therefore leads to less clouds, and a less active sun leads to more clouds.
The fourth IPCC report dismisses Henrik Svensmark’s theory as ‘controversial’, and ignores it. The fifth IPCC report is interesting. The draft report leaked by Alec Rawls admitted strong evidence for enhanced solar forcing: “Many empirical relationships have been reported between GCR or cosmogenic isotope archives and some aspects of the climate system . The forcing from changes in total solar irradiance alone does not seem to account for these observations, implying the existence of an amplifying mechanism such as the hypothesized GCR-cloud link.“, but the final report contained no such statement and continued to treat total solar irradiance alone as the sun’s only influence.
Henrik Svensmark’s theory has been confirmed in many tests and experiments. For example, by Laken et al (2010) “These results provide perhaps the most compelling evidence presented thus far of a GCR-climate relationship. From this analysis we conclude that a GCR-climate relationship is governed by both short-term GCR changes and internal atmospheric precursor conditions.“.
This might not be the only sun-cloud connection, but the simple fact is that the sun-GCR-cloud link does exist.
Much of CO2 theory has been confirmed in many tests and experiments. But only the direct effect of CO2 has been demonstrated. As I described here and here, the indirect effects (“feedbacks”) claimed by the IPCC are unsubstantiated and their use is unwarranted..
The direct effect of CO2 – “Climate Sensitivity” – is generally agreed to be about 1 to 1.2 deg C per doubling of CO2. Some studies observe much lower climate sensitivity (eg. here), but to be on the safe side I will use 1.2. [NB. Studies which find a higher sensitivity tend to be model-based, ie. they make the same errors as the models].
Applying the same data and formulae as I used here, but with a climate sensitivity of 1.2, projected temperature increase from 1750 to 2100 is ~2 deg C. That is using the “Business as Usual” CO2 projection, which reaches 1,030ppm in 2100. Some other years are:
Table 1. CO2 concentration and temperature projection for ECS = 1.2.
For an ECS less than 1.2, the ‘Deg C’ figures in Table 1 would be lower.
At Mauna Loa Observatory, the current (21 Jan 2017) CO2 measure is 406ppm.
2.5 Clouds vs CO2
The question is often asked: how much of the observed global warming is from CO2 and how much is from natural factors.
In a way, that is a misleading or inappropriate question, because it is based on linear thinking – ‘if you add the components you get the total‘. But climate is non-linear.
The way that direct ocean warming and GHG warming relate to each other is the key.
GHGs warm the atmosphere. The GHG process involves only IR, which cannot penetrate the ocean more than a fraction of a millimetre, where its energy goes mainly into evaporation. ie, the energy goes straight back into the atmosphere. Other ways that the energy from GHGs can get into the ocean is by rain being warmer, and by conduction at the ocean surface (which does a poor job). In the meantime, the atmosphere is busy radiating its heat out into space. And, of course, the heat content of the ocean is much larger than the heat content of the atmosphere. The bottom line is that it will take a very long time indeed for any GHG warming to warm the oceans. It is not exactly surprising that the IPCC do not attempt to say how long it takes to reach equilibrium.
Clear sky – absence of clouds – warms the ocean in and below the surface. That warmth, as explained above, later warms the atmosphere on various timescales. But net heat transfer between ocean surface and atmosphere is from the one that is warmer to the one that is cooler. So, for example, if the atmosphere is already warmer then the ocean will not warm it any further – although it could slow down the rate at which it cools.
So in simple terms the relationship between Clear Sky warming and GHG warming is that GHGs warm the atmosphere and Clear Sky warms the ocean, and then the two of them look for a balance. If the ocean is warmer then it warms up the atmosphere on various timescales as described earlier. If the atmosphere is warmer then it radiates to space.
By 1980, global temperature was no more than about 0.5 deg C higher than in 1850, which was probably little warmer than 1750. The global temperature has since gone up by about another 0.5 degrees C. So the global temperature over the last few decades has been much higher than the temperatures that could be expected from CO2.
/Continued in Part 2.
Mike Jonas (MA Maths Oxford UK) retired some years ago after nearly 40 years in I.T.
AMO – Atlantic Multidecadal Oscillation
APS – American Physical Society
AR4 – Fourth IPCC Report
AR5 – Fifth IPCC Report
C – Centigrade or Celsius
C-C – Clausius-Clapeyron relation
CAGW – Catastrophic Anthropogenic Global Warming
CO2 – Carbon Dioxide
ENSO – El Niño Southern Oscillation
EUV – Extreme Ultra-Violet
GCR Galactic Cosmic Ray
GHG – Greenhouse gas
IPCC – Intergovernmental Panel on Climate Change
IR – Infra-Red
ISCCP – International Satellite Cloud Climatology Project
ITO – Into The Ocean [Band of Wavelengths approx 200nm to 1000nm]
NCAR – (US) National Center for Atmospheric Research
nm – Nanometre
PDO – Pacific Decadal Oscillation
ppm – Parts Per Million
SCO – the Sun-Cloud-Ocean hypothesis
SW – Short Wave
THC – Thermohaline Circulation
TSI – Total Solar Irradiance
UAH – The University of Alabama in Huntsville
UV – Ultra-Violet
W/m2 or Wm-2 – Watts per Square Metre