Steel: On detail errors in assumed solar insolation and polar ice

Posted: June 20, 2013 by tchannon in Analysis, Cycles, Ice ages, methodology, sea ice, solar system dynamics


Illustration from

Duncan Steel: Perihelion precession, polar ice and global warming (PDF).
Journal of Cosmology[1]

I’ve not had a chance to look at this item so I am linking as-is. I’m familiar enough with Berger to know this has real meat behind it. Errors would not surprise me but caveat emptor.

Something which does cross my mind is the disparity between my own knowledge of the Arctic polar ice and the professionally published versions, perhaps pointing to subtle sampling/date issues.

h/t Bloke down the pub reports his dog said the GWPF said Steel said, so I must be a mutt for believing. (I hope the Brit humour travels)

1. Journal of Cosmology seems to be a paid publication affair. Say it is peer reviewed but little is described.
Sunglasses are wise for the web site.


  1. Chaeremon says:

    OMG, the AGW is real! impresarios of the academic theatre used the Easter computus in their “scientific” climate calendars (I mean, this is how the A in AGW became incontrovertibly human).

    So, hm, what’s next: ancient rituals? prophecies in hieroglyphics? pre-Gallilean truths?

  2. Gerry says:

    To see how this relates to historical climate change, it would be interesting to compare the northern springtime insolation changes during the Roman Warm period, Medieval Warm period, Little Ice Ages, and Modern Warm period. To do this, it would be necessary to define a series of intervals that end with stop times at the end of each interval.

    Without doing the actual computation, it appears that the northern springtime insolation has probably increased fairly linearly since 0000 AD, and thus does not explain the LIttle Ice Ages.

  3. tchannon says:

    Serious matter O’ Chaeremon at the temple of the A frame.

    Seems to me that any variation in the solar irradiation at the poles would have been noticed long ago. Perfectly good measurements have been possible for many years.
    I have not though seen any actual data.

    The matter of errors in the old code is a different matter but nothing to do with A frames. Might be pertinent to do with ice ages. As if we really know historic earth orbital variation, we don’t.

  4. michael hart says:

    Looking at the 60N line, it appears roughly that day 250 (September 7) has seen the greatest relative decrease, and day 350 (December 16th) the greatest relative increase in solar flux.

    Would this be expected to be observable in the last century’s temperature records from near, say, Oslo or Saint Petersburg (both latitude 59°57′N) ?

  5. michael hart says:

    or Lerwick 🙂

  6. oldbrew says:

    ‘This north/south asymmetry has grown since perihelion was aligned with the winter solstice seven to eight centuries ago, and must cause enhanced year-on-year springtime melting of Arctic (but not Antarctic) ice and therefore feedback warming because increasing amounts of land and open sea are denuded of high-albedo ice and snow across boreal summer and into autumn.’

    We look forward to the paper explaining how rising levels of trace gases could alter the tilt of the Earth.

  7. The idea of apsidal precession – causing changes of insolation/surface temperatures/climate – is more or less a mainstream.
    But in my opinion on the global scale it has only longterm effects (not significant at centenial scales) and the shorterm (decadal/centenial) effects of insolation changes are rather caused by direct changes of the solar activity/TSI.
    Also I think the main reason why apsidal precession has major influence on the climate is not mainly the changes of the high latitude regions insolation (anyway in absolute numbers quite low in comparison with the changes in the tropical regions), but the changes in the insolation of the open ocean (vast majority of which is at southern hemisphere and at latitudes under polar circles) – and therefore changes in the ocean heat content/surface temperature – because the ocean has very considerably lower albedo/high tansparency to solar spectrum/higher solar radiation absorbtivity than landmass and at the same time considerably higher heat capacity.
    Due to the considerably different properties of the seas compared to landmass when it comes to the effects of the solar irradiance most of the solar irradiance reaching the Earth surface is absorbed by the seas (according to my calculations about ~90% of the solar shortwave irradiation reaching the Earths surface, absorbed/extinct there and converted to heat is absorbed and converted to heat by the seas!) On the other hand the liquid water is relatively very opaque to mid-IR spectra, in order of million of times more opaque than to the solar shortwave spectra (see here:, the mid-IR cannot significantly penetrate seas deeper than several tenths of milimeter, mainly co-causing the ocean surface skin evaporation (+convection=>transporting latent heat way up to the atmosphere), not cause significant ocean heat content change – so even if the GHE backradiation would cause a warming of the air and landmass as the CO2 levels rise, it cannot cause a significant change of the ocean heat content/surface temperature – it is physically impossible – therefore to attribute the observed sea surface warming to GHG content rise in the atmosphere is one of the major flaws in the GHE hypothesis as the sea surface warming only can be caused by the solar shortwave/TSI rise – and in fact the observed global sea surface temperature change in the 20th century is quite consistent with the TSI rise. -According to my calculations from the Solanki TSI reconstruction for the 20th century the empirical dependence between sea surface temperature change and TSI change is up to 1 degree Celsius per 1 W/per square meter average 1AU ToA TSI change – depending on how long the TSI change period lasts, how steep is the trend slope and therefore how complete the temperature equilibrium state change then is. see:
    Just btw. the apsidal precession causes globally averaged solar forcing change of about ~5-7 W/square meter between the turning points – when the perihelion is synchronous with winter (more insolation of the ocean) versus with summer (less insolation of the ocean) solstice – which I think is well cappable to trigger runaway glaciation at both hemispheres when the perihelion approaches the summer solstice – which will inevitably happen in less than 10 thousand years from now.
    So to speak about CAGW, “Venus-like GHE runaway effect” and like – when even if the ice sheets would continue to melt at current rates it would take several tens of thousand years for them to melt completely and potentially give way to a runaway warming of the oceans – is a real disgrace for science, especially when in fact the opposite – the runaway glaciation – is in the pipeline and one can hardly imagine a technology cappable to offset the minus 5-7 W/per square meter apsidal precession forcing, moreover with strong positive feedback given paradoxically by the warm oceans and therefore more precipitable water available in the air to form the snow&icesheets over subpolar landmasses in the transient period, rise the albedo and eventually lead to ice age.