Author Tim Flannery says that greenhouse gases are a lot like bedcovers: they're trapping heat close to our bodies.
Now things are warming up, and we're starting to sweat underneath the cover... but we can't take the blanket off.
"There are about 30 different greenhouse gases and they all trap different wavelengths of heat energy, so altogether they're becoming quite effective in terms trapping more heat around the planet than we've had previously," said Flannery, who wrote 'The Weather Makers: The History & Future Impact of Climate Change'.
So carbon dioxide isn't the only compound that traps heat--methane, which comes from landfills and agriculture and accounts for about 9 per cent of global emissions, would be produced even if we stopped burning fossil fuels completely.
Flannery said that small concentrations of greenhouse gases occur naturally, but the amount that we've injected into the atmosphere is unprecedented - and the sky isn't as vast as it seems.
"If you think about the atmosphere it seems to be very large because when you look at the sky, it looks like it goes on forever," Flannery said.
He says that if the gases in the sky were compressed into a liquid, the volume would be 500 times smaller than the world's oceans.
"We've had three atmospheric pollution crises over my lifetime, acid rain, and then had the ozone hole, and now greenhouse gas pollution," Flannery said.
"It's all been because of one basic factor: that the atmosphere is very small as a receptacle for pollution."
The writer-scientist explained that we're making the weather by putting megatonnes of carbon into the sky, and it's not just vanishing into thin air.
"What's tending to happen now is that greenhouse gases are building up in the atmosphere and trapping heat close to the earth," Flannery said.
Even if you have as little faith into climatologist's doomsday predictions as in your local weather forecast, Flannery's book gives examples of changes that are already happening, and the evidence is hard to deny.
"Heat is being transferred to the oceans and into the soils and it's really changing a lot of the way our planet works, and that's what's changing our climate," Flannery said.
As the oceans heat up, they're starting to be able to absorb less heat, leaving more in the atmosphere and making mercury rise around the globe.
They're also losing carbon-storing plants because the warmer surfaces are deprived of life-supporting nutrients.
Flannery said that the most productive oceans in the world have a surface temperature of about 10 degrees Celsius because there's no stratification.
When the top of a body of water is much warmer than the bottom, prevents nutrients from cycling up and nourishing life close to the water's surface, stratifying it.
"As we get more and more heat on the surface of the planet, we're getting more warm water on the surface of the oceans, so we're getting less productive oceans," Flannery said.
"We can see that in the southern ocean in Antarctica very clearly where plankton numbers have dropped dramatically."
Flannery said the excess heat is also going into soils, and that the rising temperatures are doing more than creating droughts: moister areas are becoming ideal breeding grounds for bacteria, which decompose things faster, releasing more carbon into the air.
"In Europe, where the soils are naturally more moist but are now getting a lot warmer, there's much more carbon coming out of the soil," he said.
"Under warm conditions decomposition just moves quicker--that's why we have fridges."
As the ocean absorbs less heat and the soils emit more carbon, the earth gets warmer, creating a positive feedback loop, amplifying the cause and the problems.
Flannery said the writing on the wall should be enough to push the world into action, while the climate's still under control.
"We have to understand that there's a threshold beyond which these changes become run-away changes. Scientists can never say exactly where that threshold is but we've got a fairly good idea that it's around 450 parts-per-million of carbon dioxide in the atmosphere."
In about ten years, if nothing changes, Flannery said we'll hit the magic number--and the ability to change the weather may slip from our hands.
"We have to take pretty urgent action. If not, we may lose control."
