A British newspaper today published a list of "100 reasons why global warming is natural".

Here we take a quick look at the first 50 of their claims - and debunk each one.
http://www.newscientist.com/blogs/shortsharpscience/2009/12/50-reasons-why-global-warming.html

Here's 1-10
1) There is "no real scientific proof" that the current warming is caused by the rise of greenhouse gases from man's activity.

Technically, proof exists only in mathematics, not in science. Whatever terminology you choose to use, however, there is overwhelming evidence that the current warming is caused by the rise in greenhouse gases due to human activities.

2) Man-made carbon dioxide emissions throughout human history constitute less than 0.00022 per cent of the total naturally emitted from the mantle of the Earth during geological history.

isleading comparison. Since the industrial age began human emissions are far higher than volcanic emissions.

3) Warmer periods of the Earth's history came around 800 years before rises in CO2 levels.

In the past 3 million years changing levels of sunshine triggered and ended the ice ages. Carbon dioxide was a feedback that increased warming, rather than the initial cause. In the more distant past, several warming episodes were directly triggered by CO2.

4) After world war 2, there was a huge surge in recorded CO2 emissions but global temperatures fell for four decades after 1940.

In fact, temperatures fell during the 1940s and then remained roughly level until the late 1970s. The fall was partly due to high levels of pollutants such as sulphur dioxide counteracting the warming effect.

5) Throughout the Earth's history, temperatures have often been warmer than now and CO2 levels have often been higher - more than 10 times as high.

Which shows that higher CO2 means higher temperatures, taking into account the fact that the sun was cooler in the past. The crucial point is that civilisation is adapted to 20th century temperatures.

6) Significant changes in climate have continually occurred throughout geologic time.

Yes. And sea level has been up to 70 metres higher during warm periods. If that happens again, there'll be no more London or New York.

7) The 0.7 °C increase in the average global temperature over the past hundred years is entirely consistent with well-established, long-term, natural climate trends.

Wrong. The rapid warming since the late 1970s has occurred even though other factors that can warm the planet, such as the sun's intensity, have remained constant.


8) The IPCC theory is driven by just 60 scientists and favourable reviewers, not the 4000 usually cited.

Untrue, as even the briefest look at the scientific literature can establish.

9) Leaked e-mails from British climate scientists - in a scandal known as "climategate" - suggest that that has been manipulated to exaggerate global warming

Nothing in the emails undermines any of the key scientific conclusions. Independent groups have come to the same conclusions.

10) A large body of scientific research suggests that the sun is responsible for the greater share of climate change during the past hundred years.

The sun may have contributed to the warming in the first part of the 20th century but it has not caused the rapid warming since the late 1970s.
Lots of hyperlinks at the article's original site.

Technically, proof exists only in mathematics, not in science.

http://www.newscientist.com/blog/environment/2007/05/climate-myths-special.html

In 1956, calculations by Gilbert Plass (http://en.wikipedia.org/wiki/Gilbert_Plass) proved that Ångström had got it wrong: adding more and more CO2 to the atmosphere would trap more and more heat.

Seems like great fiction from the very first example.

http://www.newscientist.com/blog/environment/2007/05/climate-myths-special.html

Seems like great fiction from the very first example.

Not sure if you are arguing against or for but it does not seem to matter either way. The great Copenhagen disgrace has shown that we as a species are going to gamble a couple of billion lives on the idea that scientists may be right about global warming but nothing is going to be happening.

The simple facts, disregarding any belief for or against global warming, are:
1- The earth receives energy from the sun. Some of that (the more harmful frequencies) are bounced off the upper atmosphere. The rest hit the surface and eventually get converted into heat. At the same time the earth is losing heat through infra red radiation (mostly, there is also visible light of course). Those two need to be in balance, though there are some variations.
2- Carbon dioxide, and several other gases, are less transparent to infrared radition, meaning they trap heat in the atmosphere. This will result in a higher temperature before a new balance is found between incoming and outgoing energy.
3- There are other gases (water vapour most notably) that stop light from reaching the surface of the earth. These have an overall cooling effect.
4- Climate is too complicated to accurately describe. This means there will always be a degree of uncertainty about all predictions. However, those computer models are being tested against historic patterns and have become fairly accurate to predict those. Assuming our understanding of all mechanisms involved in climate are correct and complete this means their predictions are also accurate. All mechanisms known, including those pointed out by climate sceptics have been tested and if found relevant included in the models.
5- During an ice age the global average temperature is about 6 degrees celsius lower than it is now. That is the difference between our climate and 1500 meters (5000 ft) of ice over Russia, Canada, northern Europe and northern USA, and a sea level that was more than 100 meter lower than it is today. A 6 degrees Celsius rise of global average temperature would see summer temperatures as high as 40 Celsius at the latitude of Vancouver and London, and almost half the earth turned into a desert too hot for humans to live in (or about as hospitable as the south pole is).
6- The best scientific understanding of the processes involved today is that an increase of more than 2 degrees Celsius from the 1900s averages is going to tip some balances and is likely to result in changes that can not be undone before they have devastating consequences (like disastrous droughts in Africa). This however is understanding, not certainty.
7- More than half the world's population live and almost all economic infrastructure is found less than 70 meters below today's sea level. They would have to move or drown in the worst case scenario. Which means some eight billion humans (by the best estimates of the world population at that time if nothing is done to curb that) would be packed into less than a quarter of the current inhabitable land mass.

That is what our esteemed leaders gambled with for today's economic prosperity.


Eri