h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

I live in Fort Worth (Texas, USA), also known as 'Tornado Alley.' The mountain ranges in the north and west and the heat and moisture from the Gulf of Mexico means that there's a lot of wind moving through the area.

We've had:
- Four springs ago, a hailstorm with softball-sized to grapefruit-sized hailstones
- Three years ago, an unusually warm winter (shirtsleeve weather) and a cold, wet spring and early summer
- Heat waves the past two summers (over 102° F, approx. a month in duration)
- Tornadoes the past two springs, one of which hit downtown

I don't know if this is unusual for Fort Worth. I've only lived here about seven years, so it's not a good sample.

If you're looking for some good info on global warming, there's a page on the PBS website from the Nova episode. Recent studies indicate that the rate of warming is faster than any previous recorded warming of the earth. They say it's because of the carbon in the air. Our recent ozone-destroying ways have worked in our favor, because less heat is being trapped by the ozone, but the carbon's compensating for that.

I grew up in western Kansas and lived there until a year ago. I can say with some authority that the weather has been weird. We usually have bitterly cold winters with winds straight out of Canada, but the last few years have been mild, balmy almost.

Several researchers at my university have speculated that global warming won't nescasarally make things worse but could give us more violent storms and possibly shift the agricultural belt of the US to the north. Texas and Oklahomawill become more arid and the growing season of North Dakota will get longer.

I guess the think to keep in mind is that the current system probably isn't permanent and change might not be the natural distaster that keep getting forcasted. Just because it's been this way for a hundred years doesn't mean it's perfect.

I grew up in western Kansas and lived there until a year ago. I can say with some authority that the weather has been weird. We usually have bitterly cold winters with winds straight out of Canada, but the last few years have been mild, balmy almost.

Several researchers at my university have speculated that global warming won't nescasarally make things worse but could give us more violent storms and possibly shift the agricultural belt of the US to the north. Texas and Oklahoma will become more arid and the growing season of North Dakota will get longer.

I guess the think to keep in mind is that the current system probably isn't permanent and change might not be the natural distaster that keep getting forcasted. Just because it's been this way for a hundred years doesn't mean it's perfect.

Lentilla, you mention previously recorded weather changes. But there's the big problem. The amount of recorded data we have is tiny. Even if we had a thousand years of hyper-accurate data it still wouldn't be one tick of the second hand of the geological clock.
Looking back over the past 50 or 100 years may show a significant rise in average temperature (environmentalists and politicians). But looking back 500 years may show a fall in average temperature.
What about 1000 or 5000 years ago?

The nearest thing to long term records is the analysis of deep ice cores from antarctica and greenland. Though the teams may disagree on the details, the cores do show that there is major variation in the climate over the last few thousand years.

Eggzactly... Phil probably saw the same Nova episode that I did. Until they had that bright idea, they'd been going by tree ring data, which like you say, isn't enough of a sample to be reliable. Ice cores, especially in Antartica, can go back thousands of years. I think - but I'm not sure - that they're also doing the same with deep-sea sludge.

Seen it on TV, read it in the popular science press, seen the odd article in the professional science press. Still feeel like I'd love to go and work for one of the teams doing it all