Global Climate Change - The CO₂

Let's first investigate whether the culprit could indeed be CO₂ - man made or otherwise.  Well, as you can see from the chart below, CO₂ levels have definitely varied through history, and from the temperature chart you can also see that temperature has varied more or less in a similar cycle.

Carbon Dioxide Chart Sources: 2001-1958: South Pole Air Flask Data 1958-1220 B.P.: Law Dome, Antarctica 1220 B.P.- 2302 B.P.: Taylor Dome, Antarctica 2302 B.P.- 414k B.P.: Vostok Ice Core Data	Temperature Chart Sources: 2000-1979: Satellite stratospheric data 1979-1871: S. Hemisphere ground temp. data 1871- 422k B.P.: Vostok Ice Core Data

During the last 400,000 years the CO₂ levels have gone up and down, between about 180 and 300ppm (parts per million), and the only deviation in that cycle does seem to be that in CY2000 the level stood at 370ppm.  How significant is this information?

Well, the first thing you can see from the chart is that CO₂ in our atmosphere has been increasing steadily for the last 18,000 years, long before humans invented motor cars or chimneys.  So, unless you count campfires and intestinal gas, man played no role in the pre-industrial increases.  There's another very significant fact from these two charts, and that is that, although temperature does go up and down in tune with CO₂ levels, temperature rise always precedes CO₂ rise.  In other words it's quite probable that the increasing temperature is creating more CO₂ and not the other way around - or at the very least the two parameters are both being affected by the same driver, just on a slightly different timescale.  On the scale of this chart it is difficult to see the effect, but it is definitely there, and so CO₂ level changes cannot be causing the temperature changes.  

Worryingly, Earth's temperature and CO₂ levels today have reached levels similar to those in a previous interglacial cycle of 120,000 - 140,000 years ago.  From beginning to end this cycle lasted about 20,000 years and this is known as the Eemian Interglacial Period.   The earth returned to a full-fledged ice age immediately afterward!

But it is clear that human activities do seem to have caused a "spike" in CO₂ levels in the last 50 years and we are currently standing at what we are told is a "disastrously high" level, with catastrophic results likely for the planet.  Really?  No, really not.  Even if CO₂ was affecting temperature, total human contributions to greenhouse gases account for only about 0.28% of the "greenhouse effect" (see chart below).  Anthropogenic (man-made) carbon dioxide (CO₂) comprises about 0.117% of this total, and man-made sources of other gases (methane, nitrous oxide (NOX), other miscellaneous gases) contributes another 0.163%.  A fact which the warmists don't want you to hear is that there is another "gas" which is equally effective as a greenhouse gas, and it is present in vastly greater quantities.  That gas is water vapour!

Approximately 99.72% of the "greenhouse effect" is due to natural causes mostly water vapour and traces of other gases, which we can do nothing at all about.  The simple fact is that eliminating human activity altogether would have little impact on climate change.  There are a number of other factors which we are increasingly becoming aware have an influence on global climate.  They include solar cycles (short and long term), volcanic eruptions, ocean currents, clouds, the eccentricity of the Earth's orbit around the sun, and the galactic environment in which the sun and planets find themselves as the sun orbits the centre of the Milky Way galaxy.  Yes, lots of things - and we are going to examine them in more detail in the following pages.

NOTE: "Human additions" represent such a small percentage of the total Greenhouse Effect (0.28%) that they are barely visible in this "pie chart" at the scale represented. Comparing greenhouse gases by strict concentration only, the total human component is somewhere between 0.1% and 0.2%, depending on whose numbers you use.  Adjusted for GWP, the total human contribution to Earth's overall greenhouse effect is about 0.28%. Chart compiled using data provided by the US Department of Energy.