Ten Myths About Climate Change

By Professor Robert M. Carter: James Cook University

Fact: Within error bounds, AGT has not increased since 1995 and has declined since 2002, despite an increase in atmospheric CO2 of 8% since 1995.

Myth Two: During the late 20th Century, AGT increased at a dangerously fast rate and reached an unprecedented magnitude.

Fact: The late 20th Century AGT rise was at a rate of 1-2 degrees C/century, well within natural rates of climate change for the last 10,000 years. AGT has been several degrees warmer that today many times in the recent geological past.

Myth Three: AGT was relatively unchanging in pre-industrial times, has skyrocketed since 1900, and will increase by several degrees more of the next 100 years [the Mann, Bradley & Hughes "hockey stick" curve and its computer extrapolation].

Fact: The Mann et al. curve has been exposed as a statistical contrivance. There is no convincing evidence that past climate was unchanging, nor that 20th Century changes in AGT were unusual, nor that dangerous human warming is underway.

Myth Four: Computer models predict AGT will increase by up to 6 degrees C over the next 100 years.

Fact: Deterministic computer models do. Other equally valid [empirical] computer models predict cooling.

Myth Five: Warming of more than 2 degrees C will have catastrophic effects on ecosystems and mankind alike.

Fact: A 2 degree C change would be well within previous natural bounds. Ecosystems have been adapting to such changes since time immemorial. The result is a process we call evolution. Mankind can and does adapt to all climate extremes.

Myth Six: Further human addition of CO2 to the atmosphere will cause dangerous warming, and is generally harmful.

Fact: No human warming can yet be detected that is distinct from natural system variation and noise. Any additional human-caused warming which occurs will probably be less than 1 degree C. Atmosphere CO2 is a beneficial fertilizer for plants, including especially cereal crops, and also aids efficient evapo-transpiration.

Myth Seven: Changes in solar activity cannot explain recent changes in AGT.

Fact: The sun's output varies in several ways on many time scales [including the 11, 22, and 80-year solar cycles], with concomitant effects on Earth's climate. While changes in visible radiation are small, changes in particle flux and magnetic field are known to exercise a strong climatic effect. More than 50% of the 0.8% C rise in AGT rise observed during the 20th Century can be attributed to solar change.

Myth Eight: Unprecedented melting of ice is taking place in both the north and south polar regions.

Fact: Both Greenland and Antarctic ice sheets are growing in thickness and cooling at their summit. Sea ice around Antarctica attained a record area in 2007. Temperatures in the Arctic region are just now achieving the levels of natural warmth experienced during the early 1940s.

Myth Nine: Human-caused global warming is causing dangerous global sea-level [SL] rise.

Fact: SL changes differs from time to time and place to place; between 1955 and 1966, for example, SL at Tuvalu fell by 105mm [2.5mm/yr]. Global average SL is a statistical measure of no value for environmental planning purposes. A global average SL rise of 1-2 mm/yr occurred naturally over the last 150 years, and shows no sign of human-influenced increase.

Myth Ten: The late 20th Century increase in AGT caused an increase in the number of severe storms [cyclones], or in storm intensity.

Fact: Meteorological experts are agreed that no increase in storms has occurred beyond that associated with natural variation of the climate system.