Attributing climate-change data

Thursday 18 May 2006This is over 18 years old. Be careful.

The ongoing debate about global warming fascinates me, and one of the more interesting questions is how scientists determine that human actions are the cause. Many conservatives seems bent on chalking it up to natual cycles. So it’s interesting to see the Wall Street Journal publishing Scientists Explain How They Attribute Climate-Change Data. It’s a quick (too quick) overview of the ways scientists rule out various explanations for the warming being observed, and conclude that it is human action after all.

Comments

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Global Warming is one of those "scientific" topics that just rubs me the wrong way. I'm not saying that what we do doesn't have an impact on the environment, but I do think that we are being given "crisis" conclusions with a limited amount of data.

That's why, with glaciers and sea ice melting and rainfall patterns shifting, scientists smell a stacked climate deck. "We have never seen natural variability on a global scale like we've had in the last 100 years," says atmospheric physicist Michael Oppenheimer of Princeton University.

For me, that type of absolutism is just a little tough to swallow. Even if you go by nothing more than what has happened in the last 1000 years, you will see there have been drastic changes to the Earth's climate that could not have been caused by humans. There is a valid reason why Greenland was given it's name. The Vikings had settlements there for a number of years before the climate turned colder and the summers there all but disappeared.

We are constantly bombarded by comments about how the glaciers are retreating. But are they retreating everywhere or are they advancing in some places? And if so much ice is melting, shouldn't the sea levels be rising? I haven't heard of that happeneing anywhere.

I just thing that it's awfully arrogant of us to believe that we can do so much damage in 300 years when the Earth has been here for over 4 billion years. And as much as we think we know about climatology, how sure are we that our theories and guesses are really correct?

In the end, I want to see cold, hard data showing me that the Earth is warming up everywhere, consistently. Until that time, I will take what they have to say with a grain of salt, just like I do with all statistics.

Sean---
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Sean,

I don't think you'll ever see data showing that the temperature everywhere in the world is rising; our weather system doesn't work like. Global *average*, sure -- but there will always be some places that get cooler; for example, I'm sure some deserts will be vanishing as the oceans rise.

As for the bigger question -- science, like anything else, rarely offers surety. Certainly the data predominantly points to global warming; the conclusion that it's due to human effects is robust, I think, but I'm less familar with the arguments there. In this case, I'm trusting people I personally know to be intelligent, thoughtful experts. I'm not sure what a good solution is for people who don't know such experts personally ;).

The real danger with demanding personally observable effects like a general rise in sea level is that by the time you see & believe, it may be too late to do much about it. Go visit a glacier some time, and see how much of it has vanished in the last 10 years -- that might turn you into a believer!

Finally, remember that we're not really doing all that much damage to the Earth. We're just doing damage to ourselves and many other species! That's happened a bunch of times over the last 500 my, but my guess is that most people don't want it to happen again. At least not in their lifetime.

--titus
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Global warming to some extent is caused by the increasing pollution levels. Why there is so much changes in the shifting of climate, melting of ice? Its time to put stop to all this otherwise it would be too late.
Be Alert before the situation goes out of control!!!!
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jack, funny stuff, thank you.
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Patrick McElhaney 3:50 PM on 19 May 2006
"It's like observing a zillion poker hands and counting how often players are dealt a flush in five-card stud. Once you know that probability (0.002), you get suspicious if someone is dealt two flushes in a row (probability 0.000004). It might have been a fair deal, but the numbers suggest otherwise."

Okay, sure, whatever. That makes sense.

The part I have trouble swallowing is that we've been able to observe "a zillion poker hands" with such high levels of confidence.
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See, I have just enough science in my background to pick up on the important word in a lot of the statements that are made. Words like "may", "could contribute", and "might impact" cause red flags to go up in my world. Call me cynical, but I just don't trust most of the facts being given to me on the evening news. The greatest example of this is the notion that you should drink 6 - 8 glasses of water each day. This myth has been perpetuated for years and is not based on a single scientific study. http://www.sciencedaily.com/releases/2002/08/020809071640.htm

Radical changes have been constantly occurring on Earth as long as it has been around. Is it more arrogant is it that we believe that the last 400 years of human existence could do more to change the climate than nature or to think that the changes that are occuring have nothing to do with us? They both have negatives to them and absolute belief in either is wrong. Just as an example, an article on MSNBC http://www.msnbc.msn.com/id/12721432/ talked about the radical changes that occurred between 13,000 and 11,000 years ago in North America. Those changes caused the extinction of the mamouths and wild horses. Aside from over hunting by over zealous aristocrats, can scientists point to any similar extinction that has occurred over the last 2000 years? Certainly not in the last 200 years.

Is Global Warming a viable theory? Absolutely. Is it a provable Law? Not even remotely close.

Sean---
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Sylvain Galineau 7:39 AM on 20 May 2006
I am not sure it is especially interesting for the WSJ publishing this. The paper gets its conservative reputation from its editorial page, which is much further right than the rest of its non-business, non-editorial content.

Conservatives are no more or less prone to believing this than 'progressives' are bent to blame human action for all warming. In fact, christian conservatives are rather big on man-made warming - hence the appeal of this line to someone like Senator McCain, to rally both them and moderate Democrats at one stroke - while the pro-business crowd goes the other way. Same thing on the left, where trade-union types are not so hot on it - no pun intended - while others stopped asking questions years ago. This one cuts across politics and probably will for quite a while.

But politics aside, warming is still a lot more controversial among scientists than the article lets it. Especially when it comes to making 100-year predictions based on computer models which derive future temperatures not from raw physics but from long-range economic simulations, causing no end of arguments as to what the right set of assumptions and variables should be.

But then, we wouldn't read or need articles like these if this weren't deeply controversial, would we ?
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Sean: "Is it more arrogant is it that we believe that the last 400 years of human existence could do more to change the climate than nature or to think that the changes that are occuring have nothing to do with us?"

Well, pumping or digging up and then burning the concentrated remains of several million years' worth of dead plants and animals could certainly make those 400 years count. But is it arrogant to think that humans can disturb the environment more than natural cycles and events? I don't think we should so easily underestimate our effect on the natural world, labelling it as an unjustified sense of self-importance: damaging the ecosystem isn't something to be proud of - so there are no bragging rights in climate science - and if we're a significant agent in such a negative development we should recognise our role, not choose to deny it on the basis of a false sense of humility.

Sure, big things have happened to the planet that make even recent climate change look insignificant, but the big difference between those things and global warming is that it doesn't take a dinosaur extinction event to have disastrous consequences on human society. We have to tread carefully because the margins around the civilisation we know are so small.
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Claims of arrogance, humility or assertions of the thinness of civilization's margins - whatever that means - go a long way to demonstrate how hard and clear the evidence is.

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