.. And Love Global Warming

That post you linked to contained a lot of quotations from people I've never heard of, about what is the consensus on global warming? I vastly prefer real data over quotations about what other people think. Nevertheless, there was some discussion about data, but it was rather garbled:

“Most of the climate community has agreed since 1988 that global mean temperatures have increased on the order of one degree Farenheit [sic] over the past century, having risen significantly from about 1919 to 1940, decreased between 1940 and the early '70s, and remaining essentially flat since 1998.”

Um, what about the period from the early '70s to 1998? That's the problem! Even a lowly graduate student like me can find evidence for global warming during that period:

http://www.highestlake.com/canadice.html

When badhairblog quotes an English description of a graph, and leaves out certain important portions of the graph, it's no wonder that (s)he comes up with an incorrect conclusion:

“and they [global mean temperatures] have decreased or remained flat over the last 60 years. “

That's wrong. According to my research, global temperatures have risen since about 1975. You can look up other research, but I processed the Canadian Ice Data myself and I stand by my conclusions. The ice archive ends in 1998.

I saw Al Gore's movie “Inconvenient Truth” last week. He cites numbers of papers in peer-reviewed journals as evidence for “consensus”. I didn't check his numbers, but I would have to say that real numbers beat quotations in science.

As Kevin implied, the question is not if earth surface temperatures are getting warmer? They are, especially in the polar regions. The question is how much of that warming is due to human causes? In this important matter Al Gore's movie confuses causation with correlation. He shows two time series: the first of global temperature, the second of concentration of carbon dioxide. It's very easy to see that the two lines move together.

But which one causes the other? Or is there a third undiscovered quantity that is forcing them both? “Inconvenient Truth” kind of glosses over that issue. It could be that more anthropogenic carbon dioxide is warming the earth. It could also be that a warming earth (from some unknown cause) is producing more carbon dioxide on its own.

How? Well, maybe a warmer ocean holds less dissolved carbon dioxide. Try taking two cans of soda. Leave one in the refrigerator, and one in a warm place. Open them both together, side by side. Which one fizzes more? Enter a comment to tell us your results. Extra points will be given for some quantitative measure of the difference (count the bubbles).

Of course there are real climate scientists sorting out which is the cause and which is the effect, and they are using methods besides cans of soda! I am taking the Climatology class in the fall. I'll let you know what I find.

That post you linked to contained a lot of quotations from people I've never heard of
Just because you never heard of them doesn't disqualify their data. I specifically mentioned
1. Richard S. Lindzen,who is the Alfred P. Sloan Professor of Meteorology at the Massachusetts Institute of Technology
2. Dr. Dick Morgan, former advisor to the World Meteorological Organization and climatology researcher at University of Exeter, U.K
3. Dr Art Robinson of the Oregon Institute of Science and Medicine
4. and the Friends of Science video at Flopping Aces.

While I do not question your Canadian ice data, neither do I question the qualifications and conclusions of the scientists I mention. I stand by my post.

If you want to take the earth's temperature, where do you stick the thermometer?

And with global warming, we're not talking about the earth's temperature, we're talking about the earth's atmosphere's temperature.

My problem is this - historical data show either no correlation between CO2 levels and temperature, or CO2 lagging temperature (my recollection of arctic ice data -- sorry, thus no link). So is there something new under the sun? I don't think so.

I've heard one environmental scare after another and none have come to pass, so excuse me if I make fun of Al Gore's unscientific claim that Florida is going to drown unless we all start to worship mother Gaia. Or the fun claim that poison ivy is going to run riot -- which is true to the extent that all plant life is going to run riot, and has been for a few decades because of the fertilizing effect of CO2.

Again to the big picture - we're in an intergalacial period, which means the next big shift in climate is that a layer of permanent ice comes slithering down out of the north and ends not too far north of where I live -- as it has in the past. And there used to be a time when the earth was much hotter - no ice at all the poles. So this talk about "hottest on record" is complete bosh - what they really mean is the hottest we've directly measured with modern thermometers.

So yes, the atmosphere may be warming, and the uneven changes in temp over time might have to do with other feedback mechanisms kicking in and then being overwhelmed by rising CO2, or it could be the atmosphere is warming for reasons that have nothing to do with us. And since we know that the Earth has experienced fairly large changes in temperature without any input from we puny humans, excuse me if I don't think that this time, it's different.

Fausta:

I was beginning to smell an Argument From Authority in your post, and I am deliberately undermining that aspect for the benefit of our readers. Your extensive use of quotations instead of data is the usual way to Argue From Authority. I'm not discounting the data, I'm discounting the quotations. However, since you have identified the people clearly, I can now look up their data with Google. Thank you for supplying that information.

Another question: Why does Dr. Dick Morgan get to criticize the IPCC for not using a 30-year average, but for some reason it's okay for Dr. Richard Lindzen to claim that the global mean temperature is “remaining essentially flat since 1998.”? 1998-2006 is only 8 years. But I digress.

The term “global temperature” generally refers to the temperature of the atmosphere at the surface of the earth, where we live. Carbon dioxide is important to global warming because:
a) it absorbs infrared wavelengths
b) it's increasing

Point a) can be verified in a lab. Point b) is taken from the “Keeling Curve”:

http://en.wikipedia.org/wiki/Keeling_Curve

A scientist named Charles Keeling has been measuring the atmospheric content of CO2 since about 1960. The Keeling Curve shows two signals: an annual oscillation superimposed on top of what looks like an exponential increase. As I read the graph, CO2 parts per million were about 318 in 1960 and 380 in 2005. That's an increase of 20% over 45 years.

A reasonable hypothesis is that if something is surrounded by carbon dioxide, and the levels of CO2 increase, then that something will get hotter as more infrared is absorbed. In our case the “something” is the planet earth. The hypothesis of global warming caused by increased levels of CO2 is pretty reasonable.

But the atmosphere is a complex place, and this simple hypothesis might not be correct. There might be something else going on. For example, a warming earth (from unknown sources) might be giving off more CO2. From the oceans, for example.

I tried the “soda” experiment last night. To my surprise, the results were not what I expected! But here I am, faithfully reporting them like a good scientist.

I took two cans of Sprite. I left one in the refrigerator and the other on the kitchen counter for three hours. Then I took two identical drinking glasses (clear glass, tall) and chilled one for about 20 minutes so it would match the temperature of the cold soda. I opened each can and poured it into the corresponding glass. And then I saw . . .

It seemed to me that the cold soda fizzed more, not less. I tried counting the bubbles that made it to the surface. The warm soda sent 25 bubbles to the surface in 15 seconds, and the cold soda sent 30 bubbles to the surface during the same time period. I expected that the cold soda would “keep its fizz” for longer, but I was wrong.

What does this mean? If the results of my little experiment are to be trusted, and applied to the oceans, it means that the warmer oceans are not contributing to the rise in CO2 levels shown by the Keeling Curve. That hypothesis is ruled out. We have to formulate another explanation. This is how science works.

I was suspicious of my little exercise in counting bubbles, so I looked up some references. Sure enough, most sources agree that a warmer ocean should hold less carbon dioxide and give it up to the atmosphere. But how much less? Dr Jarl Ahlbeck at Abo Akademi University, Finland, says:

http://www.john-daly.com/oceanco2/oceanco2.htm

“If we assume that the whole ocean (mean depth 3795 m) is in equilibrium with the atmosphere, a one degree celsius global warming will increase the atmospheric carbon dioxide concentration by 28 ppm.”

The Keeling Curve shows an increase in CO2 ppm of (380 – 318 =) 62 ppm. If we assume that the ocean temperature has increased 1 degree Celsius during that period, we can only account for (28 / 62 = ) 45% of that CO2 increase. Naturally warmer oceans are not sufficient to account for the increase in carbon dioxide. It looks likely that the forcing is in the other direction (more CO2 causes warmer oceans). Other explanations are welcome, but be prepared to make some measurements and real calculations.

I'm not pretending that this analysis is rigorous; I'm posting it as an example of how scientific methods are used to sort out cause and effect. I'm sure I'll find out more in Climo class.

(Maybe I had a little speck down in the bottom of the cold glass that was acting as a dissolution nucleus.)

Florida is not going to drown any time soon. The highest estimates I've seen for sea level rise over the next century are on the order of 1 meter. So in Missouri you won't see the ocean coming over the plains, but you might get another bunch of refugees the next time New Orleans gets flooded.

Carl,
I clearly identified the people in my article in the original post. It's still exactly as originally posted.

Good luck with the soda.

The graph at the link below shows CO2 and temperature data from the Vostok ice core over 160,000 years:

http://www.classzone.com/books/earth_science/terc/content/investigations/es2105/es2105page06.cfm

They look pretty correlated to me. Since CO2 and temperature are in a positive feedback relationship, either one can lead the other. Let's say the magma in the earth's mantle gets all stirred up and it heats the ground somewhat. I would expect surface temperature to lead CO2 concentration. Now let's say the earth passes through a cloud of interstellar CO2 and collects a bunch of it. In that case I would expect CO2 to lead temperature.

If we burn up a major portion of the biosphere (either by striking the Yucatan with a meteorite or simply burning fossils fuels), I would expect the CO2 concentration to rise before the temperature does. And that's what we see: the Keeling Curve is already rising in 1960, but the temperature doesn't really begin to ramp up until 1975.

Carl,

You might want to tell Al Gore he's all wet with his animations showing Florida sleeping with the fishes.

As far as lead/lag of CO2 and temperature, these guys come at it from different directions:
CO2 Science

Real Climate
but both cite statistical analysis of ice core data (sorry if I prefer that to your mark I eyeball) showing the CO2 rise lags the temperature rise in the data. They differ in what that lag means.

And again - the ice core data shows that the temperature is constantly changing on every time scale (along with CO2 concentrations BTW), that the temperature rose abruptly 15,000 years ago by about 12 degrees F (which I doubt had anything to do with us humans), and that the trend has been cooling (although not steady as the temperature is never steady) ever since - despite a significant spike about 5,000 years ago.

I just find it odd that one can look at a graph like that and then say this little change right here, that blip at the end, that's because of us.