Copenhagen…

Sorry, but this is a long and wordy one.

Carbon dioxide makes up about 0.038% of dry air. When I left Marlborough in 1987 it was 0.035% of the atmosphere; when my father left the same establishment in 1958 the value was 0.031%. These changes might seem very small but CO₂ has a remarkable ability to absorb heat radiation over a wide range of wavelengths. Its concentration has increased by about 35% since the Industrial Revolution. This absorption of heat is causing the climate to change.

Much of this increase in CO₂ is thought to be from our burning of fossil fuels and the continual cutting down of rainforests. The environment has adapted to cope with emissions of CO₂ from animals, rotting vegetation and volcanoes but it cannot absorb the increased production from our industrial activity. CO₂ is soluble in water so the oceans have absorbed about 30% of the CO₂ emitted by human activity. The solubility of gases in water decreases as temperature increases so the oceans’ ability to absorb more CO₂ is decreasing.

Earlier this month, leaders from across the world met in Copenhagen to discuss what can be done about the changes to our climate. The hope was that global limits could be imposed to stop the average temperature increasing above 2°C. Whilst the meeting did agree that developed nations would contribute $100 billion to help developing nations cope with reducing carbon emissions, it did little to stop the rise in temperatures. A 3.5°C average temperature rise is now predicted by 2100.

Rises in temperature are harmful because they might reach a ‘tipping point’, causing such huge changes to our climate that they will spiral out of control. The science is incredibly complex but all the evidence suggests that it is a genuine concern and not something to be dismissed.

“We should have done better,” UN climate chief Yvo de Boer told journalists before hurrying away. A senior European environmentalist, John Lanchbery of Birdlife International, called the accord “a carefully managed collapse”. New Scientist

The video below (from PotHoler54) has a few long words in it, and the pictures are a little blurry, but it does explain the situation very well.

There is not much that individuals can do, although every little helps. But reducing your consumption makes great economic sense and it helps you to think more carefully about your actions. What you can do is become informed. Listen to the arguments and challenge the facts you are given. A great deal of misinformation is spread about all aspects of science and your greatest defence is to be sceptical and demand to see the evidence.

Try my survey. Get your family to vote too, although you might only be able to vote once from any given computer.

[yop_poll id=”2″]

<geek alert> You could try clearing your cache if you want to vote multiple times! </geek alert>

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Questions…

1. What are the percentages of nitrogen and oxygen in the air?
2. What happens to the pH of water as more CO₂ dissolves in it? How might this affect animals that make their shells out of calcium carbonate (limestone)?
3. What other gases are considered greenhouse gases? How do they get into the air?