Art Hobson explains Global Warming

[Dardedar]

MODERN TIMES

Art Hobson

ahobson@uark.edu

NWA Times 28 Feb 2009

The plausibility of global warming

A 2008 Pew Poll found that less than half of all Americans agree with the scientific consensus that global warming is real and human-caused. This contrasts with the scientific consensus, as expressed in the 2007 Intergovernmental Panel on Climate Change report by over 2000 climate scientists who assessed tens of thousands of peer-reviewed scientific papers published during 2000-2005. That report stated that "warming of the climate system is now unequivocal" and that there is "very high confidence" that this is at least partly due to humans.

I witnessed this consensus last week at a national meeting of the American Association for the Advancement of Science, probably the world's most prestigious large scientific organization. Al Gore was invited to speak. The large lecture hall was overflowing. Gore received a standing ovation both at the beginning and end of his talk. The enthusiasm for this man who has so raised public awareness of global warming was palpable.

Public skepticism about global warming stems partly from a gut feeling that human actions are too puny to warm our huge planet. Allow me to explain why this gut feeling is wrong. For this, we must understand the greenhouse effect of Earth's atmosphere.

It's true that the human energy input is relatively small: 99.98 percent of Earth's energy comes from the sun and only 0.0075 percent of the total comes from fossil and nuclear fuels. The energy from the sun must, on the long-term average, be radiated by Earth back into space. If, for example, Earth radiated less energy than the energy that comes in from the sun, our planet would warm and the increased temperature would cause Earth to radiate more strongly until, eventually, the radiated energy balanced the incoming energy from the sun.

The amount of energy radiated by Earth is determined by Earth's overall temperature, just as a hot plate's radiative properties (white hot, red hot, dim-red, no visible glow) are determined by its temperature. When this is put into the form of a couple of simple equations, the overall Earth temperature required to balance the incoming energy from the sun can be calculated to be minus two degrees Fahrenheit.

But Earth's surface isn't this cold. Minus two degrees would freeze the oceans, for one thing. The answer to this dilemma is that minus two degrees is the temperature of the top of the atmosphere; this extreme outer surface must be at minus two degrees for the planet to "glow" sufficiently to balance the sun's energy. Like a warm but not visibly glowing hot plate, this low-temperature glow is invisible "infrared" radiation, not visible light.

Earth's surface is much warmer than minus two degrees, because the surface lies under a thick atmospheric blanket. Like the blanket on your bed on a cold night, the bottom of this blanket is much warmer than the top. Just like a blanket, the atmosphere warms us by trapping some of the infrared radiation that the surface emits toward space. This trapping is called the "greenhouse effect" but "blanket effect" is more accurate.

The warming "insulation" in Earth's greenhouse blanket involves only a few trace chemicals known as "greenhouse gases," not the nitrogen, oxygen, and argon that form far more than 99 percent of the atmosphere. This insulation is almost entirely water vapor and carbon dioxide (CO2), forming far less than one percent of our atmosphere. These few water and CO2 particles are such efficient absorbers of infrared radiation that they cause the bottom of the greenhouse blanket to be nearly 60 degrees warmer than the top, resulting in a pleasant 58-degree average surface temperature.

Three-quarters of the greenhouse effect is caused by water vapor, one-fifth by CO2, and the remainder by other trace chemicals. Humans and ongoing natural processes can't alter the amount of water vapor by much, because the atmosphere can hold only so much water before it condenses into droplets and "rains out." But humans can and have altered the amount of CO2. Before the industrial age, for at least the past 800,000 years there were never more than about 280 CO2 particles in the atmosphere for every million air particles. Now there are 386. We know that most of the excess CO2 comes from fossil fuels (the rest comes from de-forestation) because this long-buried fossil carbon is physically different (it contains no radioactive carbon-14) from natural atmospheric carbon and can thus be detected in the atmosphere.

So humans have increased the greenhouse blanket's CO2 insulation by nearly 40 percent. In view of the 60-degree natural greenhouse effect, it's not surprising that this has raised Earth's temperature by 1.5 degrees, with 6 degrees expected by 2100 if present emissions continue. What we've done is analogous to replacing a cotton blanket with a wool blanket. On a cold night, the top of both blankets are at the same temperature but the bottom of the wool blanket is much warmer because wool retains more of your body's heat.

So global warming is unsurprising. A thin trace of water vapor and CO2 causes nearly all 60 degrees of natural greenhouse warming, and we've increased CO2 by 40 percent. Since CO2 causes 20 percent of the greenhouse effect, we should expect that we've increased the greenhouse effect by several percent, or a few degrees. It's not the total energy input by humans that's causing global warming, it's the greenhouse gas input.

What is surprising is humankind's lackadaisical and skeptical response. We'd better get smart fast.

Link to Art Hobson's Homepage

[redheadedskeptic]

I think part of the problem here is in the presentation. If you watch Al Gore's video, a majority of his evidence comes from charts and graphs. In the trailer which is played and re-played, he uses as evidence for global warming how summers are getting hotter and hotter. But when people use colder winters as evidence that it is not happening, they are treated like they are illogical and ignorant, even though it follows the same line of reasoning with which they have been presented. Run a google search for global warming: you won't find good, thoughtful papers that explain global warming in plain, unbiased language. Everything immediately available is trying to convince people of their personal viewpoint, which I find unscientific. On top of that, some evidence seems to be contradictory: I have read that Antarctica is shrinking, but I have also read that while it is shrinking in some places, it is expanding at the rate of a mile per year in other places. I have no idea which is true as I have never been to Antarctica. In all the lay literature, everyone accuses everyone else's methodology of being wrong. A friend of mine who is nearly finished with her PhD in chemistry found an article last week blaming global warming on the increase in food allergies! Media pointing a finger at global warming for everything also makes it sound less credible to those who are skeptical.

Then, even if you can get a consensus that global warming is happening, you have very wide ranges of debate over how much effect it will have and if there is anything you can do about it anyways.

Personally, I find the entire topic very confusing as I have no education whatsoever in climatology. I don't want to be the one person who still believes the Earth is flat, but neither do I wish to be one of the 50,000 people who believe in a stupid idea. I believe that the media sensationalizing the problem and using global warming as a scapegoat for everything has contributed greatly to people's skepticism. I mean really, if you do an honest search and do some honest thinking, it really can get overwhelming and confusing. And for me, I don't find the subject interesting enough to dig through academic journals and the like--I have more than enough reading to do for my classes as it is, and really, it is not that important to me to find the answers as believing in it 100% or 50% would not change my behavior--I believe in recycling and would drive a hybrid car if I had the money to buy one, and I try not to waste energy, etc.

If people want the public to believe in global warming, they are going to have to present it in a way that the public can understand it.

And now that I have probably made myself sound incredibly stupid, I will quit talking.

[Doug]

I think part of the problem here is in the presentation. If you watch Al Gore's video, a majority of his evidence comes from charts and graphs. In the trailer which is played and re-played, he uses as evidence for global warming how summers are getting hotter and hotter. But when people use colder winters as evidence that it is not happening, they are treated like they are illogical and ignorant, even though it follows the same line of reasoning with which they have been presented.

DOUG
It is the average temperature that is really telling. Summers are hotter on average, but so are the winters. (Many ski resorts are going bankrupt because of it.)

We used to have a global warming denier on this forum. He got globally roasted to a crisp. Check out some of the older science posts. There's plenty of evidence there, hopefully rather accessible.

[redheadedskeptic]

We used to have a global warming denier on this forum. He got globally roasted to a crisp. Check out some of the older science posts. There's plenty of evidence there, hopefully rather accessible.

Let me clarify that I would not at all consider myself a global warming denier. In my previous post, my main point was to try to explain why I think that many people are, apart from the completely ridiculous religious reasons. I will confess that it is the area I have struggled with the most, as I explained rather poorly by my last paragraph in my first post, primarily because I had the misfortune of hearing the negative arguments prior to the affirmative--probably another reason at least a few people may have a hard time with it. To explain further where I am coming from, my education about global warming separate from religion was a combination of scare tactics and hearing how global warming is a hoax. I don't respond well to scare tactics anymore--try to tell me the whole world is going to end and I am immediately turned off. I don't respond well to conspiracy theories either, but it did prompt me to do some research. I did do further research, trying to find good articles explaining why certain things the way they were or trying to find out answers to questions I have had, but it was very difficult! The difficulty did not lie in the readability of the articles, but in the many contradictory articles you can find. I, like many, am not well educated enough in the topic to sift through what is genuine and what is crap. (As opposed to say, religion or psychology--I know enough about those subjects that if presented with two contradictory pieces of evidence, I could probably reason which is more likely to be true based on what else I know of those subjects.)

Even now, while I generally accept it to be true because I know that just because I don't understand something doesn't mean it's not true, I still have questions. What I was trying to say with my second paragraph is that if anyone asks a genuine, honest question, instead of explaining the answers, I have often seen that person get "roasted to a crisp" as you say (though I am sure in that case it was probably well deserved! I couldn't find the particular thread.). Again, the public is often poorly educated on the subject, in part thanks to a media that does not understand it either. If people want others to understand global warming, they are going to have to explain it calmly to people who don't, and perhaps stop treating those who have genuine questions (though I know full well that not everyone's questions are genuine) as if they are ignorant, stupid people who are worse than the Creationists. Honestly, I probably would not have had nearly such a hard time with it if I felt freer to ask open questions about it and not be treated like a homeschooled third grader!

In short, I was trying to explain some of the difficulty from the perspective of someone who once would have fit into the 55% in the poll, not argue against it. I obviously failed!

[Dardedar]

I think part of the problem here is in the presentation.

DAR
Hello redheaded!

Don't you find Art Hobson's explanation above quite accessible? I am a high school graduate with no college and no science background and I thought his explanation above was one of the best I've seen. Art is a local retired physicist.

If you watch Al Gore's video, a majority of his evidence comes from charts and graphs.

DAR
Let's say you have a number to show for a series of years, what easier or better way could there be to show it to non-experts than a graph? I don't know of any way. For instance, this chart shows the change in Antarctic temperature:

In the trailer which is played and re-played, he uses as evidence for global warming how summers are getting hotter and hotter. But when people use colder winters as evidence that it is not happening, they are treated like they are illogical and ignorant, even though it follows the same line of reasoning with which they have been presented.

DAR
As Doug mentioned, average global temperature measurements include winter and winters are unquestionably getting warmer. If you are referring to certain areas or instances, this is just called "weather." "Climate" is different and refers to a much bigger picture. Certain areas will get hotter or colder and wetter or dryer, this is weather changing as it always does. The big picture is climate change, and we are getting warmer, and with about a 95% certainty, we think we know why.

Run a google search for global warming: you won't find good, thoughtful papers that explain global warming in plain, unbiased language.

DAR
I am not sure what you are putting in Google. There are lots of sites that do this! But even one good one can do the job.

...some evidence seems to be contradictory: I have read that Antarctica is shrinking, but I have also read that while it is shrinking in some places, it is expanding at the rate of a mile per year in other places. I have no idea which is true...

DAR
The first site I look to to check these things is an award winning site written by climate scientists, is quite accessible, and has zero politics. After all, the question of how to deal with the problem (political) is a very different question than identifying if there is a problem (science). The politics makes people go nuts. The science on this is very solid. I think this article at realclimate[url] answers your question while at the same time explaining why this subject has confused so many people (bad media).

They have a whole category of articles on [url=http://www.realclimate.org/index.php/archives/category/climate-science/arctic-and-antarctic/]Arctic and Antarctic. See the panel on the right on the main page.

...an article last week blaming global warming on the increase in food allergies!

DAR
Bad media!

Media pointing a finger at global warming for everything also makes it sound less credible to those who are skeptical.

DAR
Absolutely right. If you think you are frustrated with this just imagine how the scientists who devote their life to studying these issues feel about that. But the press is what it is, and this just a distraction.

Then, even if you can get a consensus that global warming is happening, you have very wide ranges of debate over how much effect it will have and if there is anything you can do about it anyways.

DAR
There is no "if" about the consensus. See the first article at realclimate right now. To quote, [bold mine]:

"According to a recent article in Eos (Doran and Zimmermann, 'Examining the Scientific consensus on Climate Change', Volume 90, Number 3, 2009; p. 22-23 - only available for AGU members - update: a public link to the article is here), about 58% of the general public in the US thinks that human activity is a significant contributing factor in changing the mean global temperature, as opposed to 97% of specialists surveyed. The disproportion between these numbers is a concern, and one possible explanation may be that the science literacy among the general public is low."

As one person put it in something I was reading yesterday (and I know to be true): "Not one single, solitary scientific professional or honorific science organization has dissented from the consensus opinion on climate change. Not one. And it’s been examined in minute detail by the NAS, AGU and a veritable alphabet soup of scientists [and science organizations].

Now, the debate over how much "effect it will have" is a good one, and we should look to the best science. The debate over "what to do about it" is politics and completely separate (and much more squishy). The realclimate site does not, ever, deal with the "what to do about it" question.

If people want the public to believe in global warming, they are going to have to present it in a way that the public can understand it.

DAR
About five years ago I didn't know squat about the GW issue. Next to nothing. It was one of those topics I was going to get around to checking out. As mentioned I have no formal training in science but after years of honing skeptical skills and being a debunker since before age ten I will say I have a very good nose for bullshit and bullshit artists. Scary good. So, because we had a bizarre antagonist around here on the subject I used it as an opportunity to learn about this and you will find hundreds if not a thousand post on this topic on this forum. Unfortunately, many may not be useful because the intensity/volume was rather high. Most of it involved swatting down the really silly stuff (and on this issue, there is a lot of really silly stuff ).

Anyway, I think you have the exact right attitude. I understand your doubts and reservations completely. Contrary to your reservations, you have explained your position perfectly. If you have any questions I would gladly answer them or more likely steer you in the right direction to get a solid scientific answer.

Bottom line: The best science says we have 100% certainty that the earth has warmed considerably in the last century and about a 95% certainty that we humans have caused most of it. We could be wrong but it's not likely that we are. Based upon C02 science, well understood at least 130 years ago (and really brought to attention in the late 70's), we have a great concern that this C02 is going to cause warming havoc for centuries if not millennia. This is especially a problem if we continue or increase the actions that have caused this situation in the first place.

Darrel.
-------------------------------
"If you look in the climatological field, you may not see much controversy, but if you search the web, you may see something that looks like one. But I think that this controversy to a large extent is constructed out of thin air..."
--climatologist Rasmus, commenting in the current Realclimate lead article

[redheadedskeptic]

Oh, dear, now I remember why I try to not say/write controversial kind of things when I don't know someone very well! I have a hundred thoughts that go through my head, and when I try to condense them, it never comes out quite right. Okay, on to try to attempt to clean up the mess I've made!

Don't you find Art Hobson's explanation above quite accessible? I am a high school graduate with no college and no science background and I thought his explanation above was one of the best I've seen.

Yes, indeed. I was actually referring to the media in general when I wrote about the presentation problem. Art lamented the fact that over half of Americans don't entirely trust the science of GW. My apologies for my lack of clarity.

DAR
Let's say you have a number to show for a series of years, what easier or better way could there be to show it to non-experts than a graph? I don't know of any way. For instance, this chart shows the change in Antarctic temperature:

I will answer this, but keep in mind that I am only trying to clarify my meaning. My statements on graphs and charts was mainly an example for why the issue can be confusing to some people--not something I necessarily believed. In many areas of science (as I have no formal education in this field I do not know if this is one of them), you can make your statistics say anything you want.

For example, one of the first things I read about global warming is that while we are shown many charts that show a drastic increase in temperatures, charts from other stations (such as Paris and Stuttgart) do not show these same increases. In fact, it was hotter in Paris in the 1750s (I believe--sometime around that decade anyways) than it is today. As an example of someone who likes to twist their stats in another field, Dr. Dobson of Focus on the Family is notorious for doing this kind of thing.

I also understand this is only one facet of the many, many evidences for GW; again, this is only an example of how it can be confusing to someone.

So, yes, you are definitely right: the best way for scientists to show a number is through graphs. But you can make graphs say anything you want for statistical problems such as these. For the GW issue in particular, I have actually seen a couple of the same graphs presented different ways: 1 way makes it look scary, the other way, it does not. It is all in the presentation and how the scientist chooses to represent his/her numbers. Now, I don't believe that I am smarter at reading a graph on climate than a climatologist and I most definitely am not one of those people that think scientists are out to get us. This is the main reason I go with the science, even though there are things I don't entirely understand about the issue. There are things I don't understand about evolution, but I am not arguing against that, either. I just can understand why people are frustrated. I think that the logic often goes something like this: There is a scientific consensus, but the scientific consensus once told us wrong idea x, too!

There is no "if" about the consensus.

Yes, yes, again, my poor wording. My apologies.

the debate over how much "effect it will have" is a good one

I think this is another reason people get confused. I have read opinions from "it's too late, there is absolutely
nothing we can do. We are doomed in 25 years" to "It's going to be good for us in the long run." People hear this debate and think there is a debate on the whole issue, or they think, "Well, if it's good for us OR if we're doomed, there is nothing we can do about it, so why should I care?"

after years of honing skeptical skills and being a debunker since before age ten I will say I have a very good nose for bullshit and bullshit artists

You are lucky! Not all of us are so fortunate! I did not learn how to start thinking critically until I was about 20. All in all, still very new for me! This is actually why I think I personally had so much trouble on the issue. When I started letting all of the bullshit go, I let just about EVERYTHING go for awhile. I think somewhere in there, I was thinking (though I don't remember having these conscious thoughts): I believed people who were highly educated in their field my entire life (think theology here), and a brief internet search will yield the many ways in which they are flat out wrong about it all. What else have I taken for granted that is wrong? The GW issue had the misfortune of first popping up on my radar about this time. That and I heard my entire life how the world was going to end and how we are doomed for destruction. My first reaction on issues such as these is definitely to be skeptical, even if there is science to back it up.

"If you look in the climatological field, you may not see much controversy, but if you search the web, you may see something that looks like one. But I think that this controversy to a large extent is constructed out of thin air..."

An excellent quote. Again why people seem to not care or seem ignorant about it. Reminds me of the evolution/ID controversy. Also what I meant when I said the media will have to make it where the public can understand it: if you look at the media and online, there seems to be a this huge controversy. Most people look at controversial science in the media and say "They don't know what they're talking about, so it obviously isn't that big a deal" then check out.

Again, I am just using my own experiences to relate why I think so many Americans have trouble with this issue. Add religion and what seems to be a general distrust of science in certain regions, and this article does not at all surprise me. Sorry this post was so long.

[Dardedar]

I was actually referring to the media in general when I wrote about the presentation problem. Art lamented the fact that over half of Americans don't entirely trust the science of GW.

DAR
Two problems with the media:

1) They have a fine line to walk. They have trained the public (or for whatever reason accepted the game) that there are two sides to every story and they both deserve equal or fair time. This is rubbish. Some claims are just false and deserved to be exposed and then ridiculed, in that order. There are legitimate skeptical positions regarding GW. One can live in that 5% zone and think the mainstream position is wrong (including about the 5% claim). But I tell you this, the VAST majority of anti-GW material is utter garbage.

2) The "media" being part of the American populace is also scientifically, let's say, "not up to speed." Well, science is very specialized these days so one could give them a little slack I suppose. But a lot of it is just ignorance, stupidity and laziness. Twice now, Lou Dobbs, who doesn't know Jack about GW has had two GW deniers on his show (unchallenged) whereupon he feeds them borderline unintelligible gibberish filled softballs which they then use to spin their worn out, long debunked, tales. And this is CNN, Fox is worse. There is no excuse for this.

RED
For example, one of the first things I read about global warming is that while we are shown many charts that show a drastic increase in temperatures, charts from other stations (such as Paris and Stuttgart) do not show these same increases. In fact, it was hotter in Paris in the 1750s (I believe--sometime around that decade anyways) than it is today.

DAR
Two points. I am pretty sure we don't have temperature (instrument) readings from 1750. That came about 100 years later. I'll check.

Referring to temperature in a region or city is weather, not earth climate. These are very different things. Almost no one denies that the planet is hotter now than in the last 400 years, and most likely the last 1,000 years.

If you have a source referring to this I'll take a look at it. Oh, here's one. It's probably rubbish since it refers to the "heat Island effect."

RED
As an example of someone who likes to twist their stats in another field, Dr. Dobson of Focus on the Family is notorious for doing this kind of thing.

DAR
I am sure he is, but he is only one of thousands out there doing this. This is why you want to consider material that is peer reviewed. The vast majority, almost without exception, of stats getting twisted to support anti-GW material is not peer reviewed. It's just junk getting passed around by ideologues, many of them (politically motivated) scientists with training in other fields.

RED
...the best way for scientists to show a number is through graphs. But you can make graphs say anything you want for statistical problems such as these.

DAR
So what is the best solution for this human tendency toward self-confirmation bias? Peer review. That's our gold standard. It's not perfect but it works really good when we use it.

RED
For the GW issue in particular, I have actually seen a couple of the same graphs presented different ways: 1 way makes it look scary, the other way, it does not. It is all in the presentation and how the scientist chooses to represent his/her numbers.

DAR
And then the scientists duke it out in peer review, and the good stuff rises to the top. And then we have the consensus we have today. And we still may be wrong. But it's the best we have.

RED
I just can understand why people are frustrated. I think that the logic often goes something like this: There is a scientific consensus, but the scientific consensus once told us wrong idea x, too!

DAR
Yes, I remember my dad giving that one against evolution. "They used to teach the Piltdown man" etc. But let's remember, it was science that caught these mistakes and corrected them.
And there is usually a lot of distortion in these claims in the first place. For instance George Will (who I actually like) and his idiotic and completely distorted (and oft repeated) claim that there was a scientific consensus in the 70's claiming that the earth was going to cool and we should prepare for that. He searched the world for his best example of an instance of your "but the scientific consensus once told us wrong idea x, too!" and this is what he found. And it's utter rubbish.

See The global cooling myth.

And I see George Will's dishonesty continues and gets worse.

RED
I think this is another reason people get confused. I have read opinions from "it's too late, there is absolutely
nothing we can do. We are doomed in 25 years" to "It's going to be good for us in the long run." People hear this debate and think there is a debate on the whole issue, or they think, "Well, if it's good for us OR if we're doomed, there is nothing we can do about it, so why should I care?"

DAR
Well that is a tough one. How do you define "doomed." I don't think we are doomed, even worst case. But worst case will be very disastrous for a whole lot of people and animals. But we've had disasters before.

DAR
...after years of honing skeptical skills and being a debunker since before age ten I will say I have a very good nose for bullshit and bullshit artists

RED
You are lucky! Not all of us are so fortunate! I did not learn how to start thinking critically until I was about 20. All in all, still very new for me!

DAR
Actually, my boast is not quite accurate now that I think about it. While I did show an early aptitude at critical/skeptical thinking in some areas (fundie religion esp.), I also bought into a lot of new age foo foo for about a decade. It wasn't until I was about mid twenties that I actually got the tools to start to discern the difference between good ideas and nonsense. If you don't have the tools, you don't get the job done.

If only there had been a forum like this. I could have gained a decade.

D.

[tmiller51]

DAR
Well that is a tough one. How do you define "doomed." I don't think we are doomed, even worst case. But worst case will be very disastrous for a whole lot of people and animals. But we've had disasters before.

I think this is an interesting aspect to GW that doesn't seem to get a lot of discussion because of the polarization of the issue. Deciding on a response to GW may be as much moral as economic. Although the US will certainly be effected, other (poorer) parts of the world will see worse changes. We may be able to buy our way to solutions to the bad effects (buying our food or water from somewhere else when our best agricultural regions have drought, for example). Of course this is again where organized religion lets everybody down, often times caring more about building the next megachurch than using their influence to make positive changes in the life of some brown child on the other side of the earth.

Tim