Wobbly Universe

2 Feb 2007
By Christine Carter
Page 2 of 6 (go to article to read other 5 pages)

FS: Has global warming ever happened before?

JL: The climate change we’re seeing now is closely similar to a geological event that occurred 55 million years ago, at the beginning of the period geologists refer to as the Eocene. We’re not quite certain how, but about two million million tons of carbon dioxide came into the Earth’s atmosphere over a period of about 10,000 years. I think the most likely cause was a volcanic sill: lava underground from a volcano coming up beneath a petroleum deposit in what is now the Norwegian Sea. This vaporised practically the whole deposit and put a huge quantity of carbon into our atmosphere.

FS: What would the climate be like without humans?

JL: If we had never developed as an intelligent species, the climate right now would probably be moving slowly back towards the next glaciation. There’s some debate about that: some think the present interglacial era would go on a bit longer this time, perhaps as long as 50,000 years. But sooner or later we would be going back into an ice age again. Now we will not: by putting so much carbon in the atmosphere, we have irreversibly changed the Earth. We won’t have another ice age, not at least for another 200,000 years.

FS: What can we expect to see in 20 or 30 years from now?

JL: I can speak not just from my own view, but from the opinions expressed by senior climatologists who have represented their thoughts in a report by the Intergovernmental Panel on Climate Change (IPCC). The last one was in 2001, but the update is due in 2007 [February 2nd] and I’ve seen it. Quite simply, it’s very stark: it says that by around 2040 to 2050, the European summer of 2003 (where over 20,000 people died of overheating) will be the norm. People might be able to deal with the consequences: they may go away for the summer to cooler places or they can turn up the air conditioning. But for the plants and the ecosystems, there’s no such relief. European agriculture will probably cease to produce food by then, it will become a desert and scrub region. And the rest of the world will not be exempt: Asia and America will be suffering the same consequences, as will Africa and the nations of the southern hemisphere. We will be entering a world where food supply becomes more and more scarce and there will be mass migrations. Anyone with an imagination can see the awful human consequences of that, and we’re talking about something which is only about 30 years ahead.

See Also:
Causes of Climate Change Over the Past 1000 Years
Humans vs Sun as cause for climate change
Astronomer Sallie Baliunas on sunspots, global warming, ...
Global Warming - Humans and/or the Sun? ... and more!
Sun more active than for a millennium
Sally Baliunas inteviewed on Solar Fluctuations and Global Warming
Interview: James Lovelock on Climate Change
Humans, Cycles, Sun or Ice-ages - What affects our climate most?
Sun's fickle heart may leave us cold