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Post by iamspecial on Dec 13, 2009 21:51:13 GMT
What are carbon emissions?
Carbon emissions usually refer to the man-made production of a series of gases that accumulate in the atmosphere and help to warm it. Strictly speaking, not all of these so-called greenhouse gases contain carbon so some – including New York Times journalist Andrew Revkin – have labelled the phrase misleading. Some use the phrase as shorthand for emissions of carbon dioxide, which is the most important greenhouse gas produced. Often the emissions of other greenhouse gases are measured by converting them to the equivalent quantity of carbon dioxide needed to produce a similar warming effect – denoted as CO2[eq].
Why do they matter?
They trap heat sent from the Earth's surface in a physical trick discovered by Svante Arrhenius in 1896 known as the greenhouse effect. Sunlight, either direct from the sun or reflected back from shiny parts of the Earth, can pass straight through. But sunlight absorbed by the Earth and then re-emitted as thermal energy – such as from a tarmac road on a sunny day – is absorbed. As carbon emissions build up in the atmosphere, so the amount of heat they trap and send back to the surface increases. This steadily increases the temperature of the Earth's surface and drives global warming.
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Post by iamspecial on Dec 13, 2009 21:51:54 GMT
Where do they come from?
Mostly from energy use: fossil fuels such as oil, gas and coal have driven the world's economies since the industrial revolution and have released carbon emissions in the process. Almost all aspects of our lifestyles rely on access to cheap energy – from transport to central heating, which, in turn, rely on fossil fuels. Energy-intensive industries such as steel and cement have particularly high carbon emissions. Besides energy use, activities such as agriculture produce greenhouse gas emissions, either directly through changes in land-use or indirectly from fertilisers.
How much is produced?
About 26 billion tons of carbon dioxide every year, and rising. World emissions have increased sharply since 2000 mainly driven by the coal-driven economic boom in China. Carbon emissions are closely tied to GDP, so as the economy grows, so do emissions. The 2008/9 recession may reduce emissions slightly, but is not expected to have a significant impact in the long term.
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Post by iamspecial on Dec 13, 2009 21:59:46 GMT
Can it be explained by natural causes?
Measurements at the Earth's surface show that average temperatures have risen by some 0.4C since the 1970s. Scientists are confident this change can be blamed on human emissions because the increase is too big to be explained by natural causes.
Although natural factors such as changes in the sun and large volcanic eruptions are known to have warmed and cooled the planet in the past, these effects are not powerful enough to explain the rapid warming seen recently. Only an increased greenhouse effect caused by higher amounts of heat-trapping gases in the atmosphere can explain it.
What is the main greenhouse gas?
Water vapour in the atmosphere produces the strongest greenhouse effect, but it has been in balance for millions of years. Human emissions, though relatively small, tip that balance.
Carbon dioxide is the chief greenhouse gas produced by human activity. It is produced when we burn fossil fuels: oil, gas and coal. The level of carbon dioxide in the atmosphere is measured in parts per million (ppm).
Before the industrial revolution, the carbon dioxide level was about 280ppm. It is now 386ppm and rising by 2-3ppm each year. When other greenhouse gases such as methane are included, the total level in the atmosphere, known as the carbon dioxide equivalent, is closer to 440ppm.
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Post by marchesarosa on Dec 13, 2009 22:55:30 GMT
You mean that this is the ONLY explanation that warmists adduce.
Just because THE IPCC clique of "climatologists" cannot account for warming by the myriad other currently ill-understood climatic factors does not mean that other factors are NOT responsible, specialpeople.
There are plenty of folk in other disciplines still working on actually explaining how the climate works rather than explaining it away with CO2 (or even CO2 equivalent).
But even accepting that the extra CO2 theoretically causes fractionally more heating of the atmosphere there is NO evidence that the global temperature shows the "unprecedented" warming that you claim at all.
In fact, all the recent examinations of the raw data from around the world show basically flat-lining or an extremely marginal increase.
Where is the independent statistically audited empirical evidence to the contrary? It simply does not exist. We have only the national Meteorological Bureaux's historical network of measuring stations round the world. Before 1900 we have very little coverage in either time or space. The raw data that exists has been seriously tampered with by GHCN, CRU, GISS and NOAA. The evidence is scattered around this blog for those not purblind to statistics.
The only remotely reliable temp data are from the surface stations and they mostly have siting problems that distort even the RAW data.
Satellite measurements only go back to 1979. So where's the basis for the alarm?
Tree rings! Pah! Pull the other one.
Gerda is going to have to come up with something a bit better than feeding this junior school stuff to you, specialpeople.
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Post by iamspecial on Dec 15, 2009 16:17:07 GMT
Gerda?  ? Your obsessive behavior is showing again. She has not posted here. I also am quite able to read and think for myself, that one of the benefits of post graduate education |
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Post by marchesarosa on Dec 15, 2009 18:53:16 GMT
Sorry, it doesn't show.
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Post by iamspecial on Dec 15, 2009 18:58:44 GMT
Only in your opinion As most of your rant blog consists of cutting and pasting others articals - do you have an opinion and are you just a sheep ? |
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Post by marchesarosa on Dec 15, 2009 19:13:58 GMT
You've obviously not looked at the blog or you would see plenty of my own opinions.
But a blog exists, doesn't it, to bring a range of stuff before the readers?
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