Climate “scientists” look at Earth’s geothermal heat flux, see that it’s small (~0.1 W/m²), and then conclude geothermal can’t possibly predominantly explain Earth’s surface temperature. This is plain wrong. I came up with an illustration to demonstrate my point a while ago:
This is a fictional planet. I did this on purpose to accentuate my point. The question here is: Why is the surface 1000°C?
Mainstream climate “scientists” would see the small geothermal heat flux (0.1 W/m²), ignore it, and conclude it must be because Solar + Atmosphere delivers 148,971 W/m² to the surface. It couldn’t have anything to do with the 1010°C a hundred meters below the surface. Oh no, it can’t be that!
But did I say this fantasy planet even has an atmosphere? What if not? The sun only delivers 165 W/m² … Where’s the rest of the energy coming from to make the surface 1000°C?
And if there is an atmosphere … where did the atmosphere get 148,806 W/m² to give to the surface?
Climate cranks come to the rescue and claim that due to infrared absorbing gases in the atmosphere, the Sun’s 165 W/m² gets auto-magically boosted to 148,971 W/m², because that 165 W/m² can’t escape to space. You know what I have to say to that?
Some people have serious problems accepting the truth: The surface here is 1000°C because it’s 1010°C a hundred meters below the surface. Simple.
Now why is that so hard to accept? Ideological presupposition. That’s why!
Let’s take a look at a recent discussion here:
Geothermal heat is about 0.1 W/m². Solar absorption is around 161 W/m². All solar is lost on a regular basis and heat loss by the surface is very (!) dynamic. Which means that a little bit more energy from below (for example 0.1 W/m2) is easily lost, together with the dynamic 1610 times higher ‘standard heat loss’.— Wim Röst
I said that her claim, that the heat flux leaving the ground was thousands of times larger than the heat flux passing through the ground, was physically impossible.— Willis Eschenbach
So what they are both saying in our context is that a 0.1 W/m² geothermal heat flux can’t “support” a 148,971 W/m² emission from the surface, so I must be wrong!
In Willis’ view, there must be equality between geothermal heat flux and surface emission.
He believes this is needed to preserve conservation of energy. But what is he really doing?
He’s equating a heat flux between two locations to an absolute energy flux equivalent at one location. Is that conservation of energy? No!
Energy is energy, and heat flux is the energy transfer from hot to cold, i.e. a DIFFERENCE of energies at two locations. How can you compare a differential to an absolute? It makes no sense. But don’t believe me, check your own eyes:
The top of the water represents the planet’s surface.
If what Willis et al were saying was true, we should expect a steep thermal gradient from the bottom to the top of the water column – so that conductive heat flux equals emergent radiation. But what actually happens?
As you can see, the top and bottom of the water column becomes the same temperature. In other words, the conductive (“geothermal”) heat flux becomes 0 W/m².
The top of this water column is capable of emitting εσT⁴, or (5.67e-8)*(273.15+83)^4 =~ 912 W/m²
In this case, 0 W/m² has no problem “supporting” 912 W/m² ! That’s infinite times!
So why can’t a 0.1 W/m² geothermal heat flux “support” a 148,971 W/m² emergent flux?
Of course it can. It’s not a problem at all. These people are simply confused on the physics.
Now imagine they had to explain this infrared electric kettle hot water video without mentioning the heat source below. How would they do that? Well…
The top of the kettle (“sun”) emits 20°C worth of radiation to the top of the water (419 W/m²) . The water vapor and carbon dioxide in the air above the water prevents radiation from leaving to colder space, and so auto-magically the top of the water becomes 912 W/m², or 83°C. Simple!
Now do you see it?
Greenhouse Effect == Geothermal Denial.
Note: Real planetary subsurface has a density gradient, and so you will see a small geothermal heat flux. There is no density gradient in this water example, so the conductive heat flux goes to zero.
Now we take my argument down to Earth, literally. Why is Earth’s surface ~15°C?
Because geothermal “delivers” 0°C to the surface. Add insolation and subtract latent and sensible heat, and you get your 15°C. Simple. No Greenhouse scam necessary.
Enjoy 🙂 -Zoe
Happy New Year, Everybody!