Thursday, 31 May 2012

Things I don’t understand – the first of an occasional series. Underground heat

I have long been a ‘denier’ of man-made global warming alarmism. I am certain our climate varies but I don’t believe carbon dioxide emission, which is a minute fraction of the atmosphere, has had or is likely to have, a significant effect on that variation. Having a science background I have read the literature and public science materials with increasing disbelief and incredulity at the childish logic, idiotic pronouncements and absurd certainty of the alarmists.

One of the trigger reasons for my disbelief was how anyone could suggest a huge effect from a minor change to a naturally occurring trace gas while ignoring the great big nuclear reactor in the sky which continuously bathes us in energy and which has always been known to be variable in its output. The power arriving also varying because of the Earth’s orbit, which changes the distance with a complex periodicity. Astronomical orbits are not perfectly circular.

Recently another thought occurred to me. The alarmists are also ignoring what goes on below our feet. The Earth is not an inert, cold, dead lump of rock. The temperature increases very quickly -  some22 degrees per KM of depth, which is a lot - below the Earth’s surface. Basically just 50 miles below the thin surface crust there is liquid rock and below that increasing heat and pressure from nuclear decay, with a temperature of 5,700K at the centre, that’s around the sun’s surface temperature. The Earth’s crust provides some insulation for our feet but cannot hold all that heat in. Were the Sun to switch off completely the Earth would not be an inert lump of rock at absolute zero degrees. 

We also know that the internal heat of the Earth is neither static nor completely enclosed. There are areas of geothermal activity and areas where the heat breaks through as volcanoes, pouring enormous energy and heat onto the surface or heating the sea. Piers Corbyn is (I believe) using the Sun’s influence to try and predict activity that may cause volcanic and earthquake activity.

So how come I have never seen anything about the internal energy workings of the Earth in any literature or discussion? At the most trivial someone needs to prove that the Earth’s internal heat is constant and that a constant contribution to surface temperatures can be validly ignored in any models or discussion. Otherwise no assessment or calculations about energy and temperature at the surface can have any meaning whatsoever.


  1. "So how come I have never seen anything about the internal energy workings of the Earth in any literature or discussion?"

    I've pondered this one and I don't know what the answer is. There is some information out there, but not much in terms of reliable numbers.

    Maybe there is a general assumption that the effect on surface temperatures must be minor or the heat would have radiated away by now.

    Or maybe that's the assumption because anything else could easily mess up the CO2 theory.

    Yet I'm sure there's something in what you say. How much heat must seabed volcanoes and hot vents spew out? I suspect we have no idea.

    Or maybe geologists don't want to involve themselves in the climate debate.

  2. I wondered about this, I'm a meteorologist, when learning about the radiative budget of the planet I asked about it.

    Turns out the heat provided from the centre of the earth during a day is about 1/10000th of a % of that recieved from the sun over the same period.

    It actually says that in the the wiki link you provided under section 2 "Heat Flow"

  3. Possibly that's where hell is, in the centre.

  4. @James Higham - and the Devil's little helpers are on the surface. We know them as politicians!