A riposte from a 'Flat Earther'

On 8 June 2011 I attended a debate at the Sydney Institute. The topic was The Carbon Tax and Regional Australia and the speakers were Richard Marles, Labor MP for Corio and Parliamentary Secretary for Pacific Island Affairs, and Sophie Mirabella, Liberal MP for Indi and Shadow Minister for Innovation, Industry, Science and Research.

Marles argued his case for Global Warming as follows.

1. The level of carbon dioxide is rising and is at its highest levels for 800,000 years.
2. Using models Climate Change Scientists have proven that as CO2 levels rise so will the temperature.
3. Anyone who disputes this hypothesis is equivalent to a Flat Earther.

First let me say that I totally agree with the first statement and that concentrations of CO2 warm the earth.

About 70% of the sunlight that beams toward Earth reaches the planet's surface and is reflected upward again as a type of slow-moving energy called infrared radiation. The heat caused by infrared radiation is absorbed by "greenhouse gases" which slows its escape from the atmosphere. Although greenhouse gases make up only about 1 percent of the Earth's atmosphere, they regulate our climate by trapping heat. This is the "greenhouse gas effect" and without it, scientists estimate that the average temperature on Earth would be colder by approximately 30 degrees Celsius far too cold to sustain our current ecosystem. Supposedly 650 million years ago there was no greenhouse mantle and the earth was a frozen snowball. In other words we need greenhouse gases to survive.

There is no doubt that CO2 levels are rising. However it is fundamental principle of science that correlation does not prove causality. In fact there are four major greenhouse gases: water vapour, carbon dioxide, nitrous oxide and methane. My problem is that when I search the internet to work out how much each greenhouse gas contributes to global warming, I keep getting the same answer, that water vapour is the major contributor. Indeed some scientists estimate that H20 contributes as much as 95% greenhouse gas effect.

Also CO2 levels are at the highest for 800,000 years but for example 500 million years ago CO2 levels were 20 times higher but life survived. When I first learned about photosynthesis at that the earth's atmosphere contained 21% Oxygen and 0.3% CO2 I used have nightmares that we would run out of CO2 and all the plants would die. I cannot believe that so many people are now having the opposite nightmare. Also while everyone says the burning of hydrocarbons increases the level of CO2 no one complains about the commensurate increase in H20.

With regard to the veracity of models, I must confess cynicism. I worked in Venture Capital for 25 years and backed over 50 business plans. Only one business met its modelling forecasts. I once asked a colleague if he had had a similar experience. His reply was that out of 80 investments only one business had made its forecasts. Business models are much simpler than climate models.

Models are only as good as the information supplied and the assumptions made. For example as noted economist Warwick McKibbin from ANU recently noted, the reason the Treasury Model showed no loss of jobs from the introduction of a carbon tax is that the Treasury model assumes full employment. What never ceased to amaze me that any suggestion that the model could be in error would be met with the most strenuous and emotional response as to its veracity.

According to the US National Oceanic and Atmospheric Administration 2010 ties with 2005 as being the warmest year on record (1998 was the third highest). However the temperature variation of 0.62 degrees above 20^th century average of 13.9°C this is still an average temperature of 14.5°C which is cold. Sydney has average mean maximum temperature of 21.6°C and I like it. What is intriguing that while all the climate change alarmists quote the warming figures and people such as Flannery keep suggesting drought and desert, the opposite is occurring. 2010 was the wettest year on record since 1900!

It is not all bad news. According to my wine supplier there are typically only one or two great Bordeaux vintages in a decade. In the last decade however, we've had four of the greatest vintages of all time, 2000, 2005, 2009 and now 2010. Indeed 2010 has been described as looking like the greatest Bordeaux vintage ever. According Steven Spurrier of Decanter there are fewer people are spitting out their tasting this year; unfortunately this is not the case with the climate change debaters.