Carbon dioxide is not the major influence on climate
The government’s intention to introduce an emissions trading system in Australia rests upon their belief that human carbon-dioxide emissions are a cause of dangerous global warming. That belief is incorrect. Though carbon dioxide is indeed a minor greenhouse gas, the major control on earth’s climate has always been, and remains, the Sun.
The correlation between solar activity and climate was first noticed in ancient Greece in 400 BC (Hoyt and Schatten, 1997). The Sun’s solar cycles are normally 11 years long, and can vary from nine years to 16 years. There is a correlation between solar cycle length and amplitude, with the shorter the cycle the higher the amplitude. High amplitude cycles produce a stronger solar wind, changing the level of galactic cosmic rays impinging on the Earth’s atmosphere. This is measured as neutron counts at several stations around the planet. That in turn alters the Earth’s albedo by changing cloud formation, as increased galactic cosmic rays enhance cloud formation.
Variation in the Earth’s albedo due to changing cloud cover is sufficient to have caused the warming of the 20th century (Svensmark and Friis-Christensen, 1997). This is borne out by the relationship between Be10 levels in the Dye 3 ice core from Greenland and major climatic periods. Be10 is formed by cosmic ray spallation of oxygen and nitrogen. Spikes in Be10 levels in the Dye 3 core are associated with all the major cold periods of the Little Ice Age, including the un-named cold period at the end of the 19th century.