Calculating Earth's normal temperature and ending questions about global warming

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Calculating Earth's normal temperature and ending questions about global warming (7/26/05)

The equations I used in the Solar System Transportation idea got me to thinking about how all of this works on Earth. I'd heard that the planet's inclination and orbit establish 100,000 year cycles that can explain the ice ages. This is primarily due to different amounts of heating of the Earth's surface by the sun. Those changes in temperature translate to absolutely gigantic changes in surface pressure, which will carry on to the core of the planet. With more pressure the core would "consume" more of the mantle because the higher temperatures would melt more of it. It's okay though - when the orbit is corrected the temps go back down, the mantle gets back what was lost and everything is happy. Usually.

If the size of the core is changing though, that would have an effect on our magnetic field, which is generated by torrents within the core. That, in turn, might be a variable in what causes's the poles to flip every once in awhile.

More importantly it struck me that we could combine the findings of geobarometry, the study of atmosphere pressure throughout the distant past, and our understanding of the orbital issues to calculate a best guess of what surface temperature the planet should be at, meaning we could actually settle this global warming debate once and for all.

Updated 12/5/07

The trick to all of this is defining points on the surface. How big those points are will define the accuracy of the model.

Basically, start with the assumption the planet's temperature would be absolute zero. Determine how much mass is compressing the core, how hot that core is made due to all that pressure, and how much of that heat filters through to the crust and atmosphere. You can get an idea of the equations involved from my space based transport design. You'll end up with a temperature at the crust for each "point" on the surface.

Now add in the sun's effect. Roughly speaking it presents us with 1.72800 x 10^22 Joules/day (don't forget the cycles I mentioned above). That energy is imparted on the atmosphere, water, and land. By determining the specific heat of these things we can calculate the change in temperature at each "point" due to the sun's effect. Solve the equation for delta T:

delta T=Q/(c*m)

and start plugging in the values at each point to derive temperature values. Note: That temperature information will need to be used to refine mass/pressure calculations done in the beginning.

With both sets of data calculated, we can add them together, using absolute zero as a beginning point, and establish a set temperature for the planet. Global warming's effect can be seen by changing the % of the elements in the air. Refining that reading would then involved improving the resolution of the "points" and adding in other factors, such as the amount of energy absorbed by the atmosphere by the reflection of the sun's light after it hits the crust (it'll vary by color!), the effects of weather, and whatever else can be thought up.

Even cooler however is once the model matches reality we can go back in time via ice cores and geobarometry to see how it all worked back then, and finally have a full picture of our environment, from the past to the present.