05 March 2010


Certainly I see the scientific view of the world as incompatible with religion, but that is not what is interesting about it. It is also incompatible with magic, but that also is not worth stressing. What is interesting about the scientific world view is that it is true, inspiring, remarkable and that it unites a whole lot of phenomena under a single heading. - Richard Dawkins

I just like to add a qualification to Dawkins' quote. A scientific truth is a statement which has withstood tests *many* times done by many people, at many different places, at many different times. A scientific truth is true as long as no test has been found to invalid the statement. The scientific truth is a description of the natural world. It represents our human understanding of the objective nature of the natural world. If a valid proof has been established which contradicts a prevailing scientific statement, what is wrong is NOT the nature. What is wrong is our understanding of nature. For this, science is ready to accept a new statement, extending or expanding on the previously held science truth.

As such, a practising scientist is forever sceptical. Scientists are constantly reviewing established theories. It is to the interest of the scientific establishment to publish findings which break new grounds.

The climate deniers' notion of conspiracy among climate scientists to build up an argument for climate change reflects a misunderstanding of the mechanism of how science works. If someone can come up with a valid argument, testable and repeatable by others to demonstrate that there is no climate warming, this someone will be viewed as a hero and will establish fame never seen before.

The correlation between atmospheric CO2 and global mean temperature is well understood. There is a few decades' lag behind due to the huge thermal mass of earth. The current concentration of CO2 are at unseen level for hundred of thousands of years. The atmospheric CO2 is caused by human activities can be verified by examining the relative amount of Carbon-14. In nature, radiocarbon is formed when high energy atomic particles called cosmic rays break down the atoms in the atmosphere into electrons, protons, neutrons and other particles. Some of the neutrons strike the nuclei of nitrogen atoms in the atmosphere get converted into radiocarbon atoms. [source] Having a half-life of 5600 years, an equilibrium has been reached. Living organisms exchanging carbon with the atmosphere will have a carbon-14 concentration similar to the atmospheric Carbon-14 concentration. However, once the organism is dead, the exchange with atmospheric carbon will stop. The carbon-14 fixed in the dead organism will proceed with its radioactive decay as normal. Hence, the fossil fuel will have a lower carbon-14 concentration than the equilibrium. By comparing the atmospheric carbon-14 concentration to those about 200 years ago, scientists are able to confirm that the CO2 currently in our atmosphere came from the fossil fuel.

Over the last 400,000 years, atmospheric CO2 averages between 180 to 210 ppm (parts per million by volume). Since 1800, the CO2 concentration has been increasing. Today it is about 385ppm. The optimistic estimate is that if human wants to keep the global warming below 2oC, the concentration needs to be kept below 350ppm. That is we have already exceeded the safe level.

The last global financial crisis has taken away the focus we have been building up in order to reach a global agreement on how to save ourselves. Until we refocus, we are going to see the current known civilisation coming to an end.

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