Spaceship Earth: Entropy Factor #1

We travel together, passengers on a little space ship, dependent on its vulnerable reserves of air and soil; all committed for our safety to its security and peace; preserved from annihilation only by the care, the work, and, I will say, the love we give our fragile craft.
Adlai Ewing Stevenson

Global Energy Consumption

If you take widely available figures for national populations and aggregate them you get close on 6.7 billion humans on this one tiny planet.  If you take widely available figures for oil, coal and gas consumption, convert to Joules and aggregate them you get another set of figures.

Then there is geothermal, solar, tidal and hydroelectric power.  Add that lot in.

Data on global energy consumption is available online from many sources: Google, Wikipedia, BP, the World Bank, IPCC etc.  I have yet to see any report which remotely reflects the true figure.

How much energy does the entire human population really consume every year?

I have no doubt that many readers will be shocked to know that the entire human population, about 6.7 billion people consume, in the aggregate, no energy whatsoever!  Zero! Zilch!  Zip! Nada!  That is because it is physically impossible for us to consume energy.  Borrow - yes.  Consume - no.

According to the laws of thermodynamics it is impossible to consume energy.  All we can do with energy is like we do with our neighbor's lawnmower: borrow it and then give it back in a degraded, useless form.  Energy can be moved around a system, but always at a loss of utility as degraded heat.

The ins and outs of systems

Imagine a closed box.  With a push-button.  We press the button and hear a tune.  We can begin to speculate about what sort of mechanism in the box might cause the pressing of the button to be linked to the playing of the tune.

Imagine a closed box.  With no push-button.  We hear a tune.  We can begin to speculate about what sort of mechanism in the box might cause the playing of the tune.

Imagine a closed box.  Nothing more.  However long we stare at it, nothing happens.  We have no rational means of knowing or making a reasoned guess as to what is, or is not in the box.  It could be nothing.  It could be something.  It could be Schrodinger's cat, but let's not get carried away!

A system can be described in terms of its known inputs and outputs.  Whether a system is seen to have inputs or outputs or both or neither is both a matter of scale and a matter of observer location.

We can't see our universe from outside.  The scale is too vast to imagine, so we can treat it as the only 'really' closed system known.  It has no inputs and outputs we guess

Come down to the scale of our Spaceship Earth and we have what looks like a closed system.  Lot's of people treat it like a closed system.  But it isn't.  We can model the various cycles of just about everything and then add in lunar and solar tides and insolation.  So.  Can the Sun, Earth and Moon be modeled with reasonable accuracy as a closed system?  Heck no!  Put that lot in a box and you will find out within about 8 minutes what 'heat death' means.  You need a virtually infinite heat sink for the planet to cool off at night.  The vastness of space fills the bill rather nicely.

Earth: a not so very closed system

The heat reaching us from the Sun doesn't warm up the planet in a simple way.  Nor does our planet cool down at night in a simple way.  The atmosphere, land, ice and sea all do their own thing with the sun's radiation.  Mostly they reflect it or mop it up in the daytime and throw what else isn't wanted into space at night.

Then there are the seasons and day-night ratios to deal with.  The midsummer day-night average is going to be a whole lot higher than the midwinter day-night average, quite apart from axial tilt and orbital distance from the sun.

Axial tilt means the poles have one heck of a long day and one heck of a long night.  Given the relatively weak low-angle sunshine the temperature averages out to somewhere between too darn cold and frostbite.

Just as the Moon causes a lunar tide, so the Sun causes a solar tide, due to gravitational forces.  These tides add thermal energy to the system.  On top of that, as the day-side atmosphere warms up it forms a tide-like bulge which, just like the gravitational ocean tide, causes some pretty rapid fluid flows.  This atmospheric motion due to thermal energy is called a gravity wave.  A gravitational wave is something else.  Waves inside the atmosphere can also be called gravity waves.  This is what is known in scientific circles as 'confusing the hell out of non-scientists'.

Ok, let's look at it this way.  The heat of the Sun raises a bulge in the atmosphere.  There is a temperature gradient between the mid-day line and the dawn and dusk lines, and a gradient between those lines and the midnight line.  The Earth rotates so that a new bit of atmosphere is being heated: the temperature gradient shifts.  Heated air rises and cooling air falls.  This sends a ripple all around the globe.  The peak is at roughly mid-day and the trough is at roughly midnight.

An aside to astronomers, meteorologists, pedantologists and rivet-counters1: yes, I know: oversimplified.  Fer Pete's sake, give a guy a break, will you.

Right.  A wave-like motion traveling around the planet and actually measurable with satellites.  It measures like a wave caused by gravitational drag.  It acts like a wave caused by gravitational drag.  If we were super-beings or NASA and could see it it would look like a wave caused by gravitational drag.  It doesn't quack, so we can rule that one out.  In the end, it makes at least some sense to just call it a gravity wave.  Because, after all, a heat wave is a whole lot else.

If our planet were unable to dump excess heat into space at night, well, let's just say that the ice cream wouldn't last too long.  Fortunately, the laws of physics have kindly permitted Mother Earth to dump her unwanted heat into space.  Which she does, both day and night.  Sometimes the volcanoes chip in with the odd bit of magma.

In the daytime, excess solar heat is part reflected, part radiated away, which keeps living things from cooking in the excess heat.  Mostly.  At night, heat is still radiated away, but the rate is reduced by the atmosphere, which keeps things from freezing in the otherwise excess cold.  Mainly.  That's the magic of our air.  We can blow on our soup to cool it and blow on our hands to warm them.  Air: you've just gotta love it!

In the next spell-binding, knee-gripping, beer-clutching episode of this epic saga of
Spaceship Earth:

Has the gallant crew of the Starship Entropy gone stark, staring mad?
Are they blowing their supplies into space?
Tune in next time ...

Cue caterwauling.

Roll credits.

And now, a public information announcement on CO2 emissions:


- rivet counter A person obsessed with the most trivial distinguishing features of things.
From scale-model making, where a representation is held to be 'wrong' because of some entirely insignificant or irrelevant  feature. "Hah!  You sure got that 1:1000 scale ship wrong.  The lifebelts were 35.2 inches diameter, not 35.3!"