Climate Questions Answered
Write an op-ed about climate change and you get a lot of emails and questions. Here are the answers!
Climate Change
I wrote an op-ed on climate change recently (you can find a version on this blog). My argument was pretty simple:- we know how much CO2 we put in the air by burning fossil fuels
- we can measure how much is in the air
- the figures match
- we know it is our CO2 because the isotopic content of the CO2 matches that of the coal we dug up and burned
- the warming effect of CO2 is well-known to science, so we can predict the global warming the extra CO2 has caused
- that prediction matches measurements.
That's it. I admit the full story is a bit more complicated, but the gist does not change. Even though the argument is simple, I got a lot of email, much of it not pretty. So here, in the interest of truth, freedom, and democracy, are my responses. But first...
Disclaimers
Since I came out on the side of the known radical communist, Al Gore, many people questioned my motives. So I need to make some disclaimers.- I am not making any money from this. If you know a way to make money from warning about the possible dangers of climate change, please tell me!
- I am not politically motivated. I don't really like politics or politicians. I am interested in bestowing a livable planet to my grandchildren. I assume that everyone is at least mildly interested in not making their grandchildren miserable. This problem is far bigger than our sordid, debilitating, dysfunctional, crappy little local politics.
- I am not a climate scientist. I don't even really like climate science. I am a scientist. This helps, but really, most of this debate is common sense.
A Step Back
Before we get into the details, it is worth our while to step back a moment.On one side of this debate we have hundreds or thousands of climate scientists who have spent their careers building an ever-more detailed understanding of global climate. I know some of these people: they work in dingy offices, take home academic pay, and are marginally interested in politics, if at all. They're smart and could be raking in the bucks on Wall Street or in practice somewhere, but they do climate research instead. I guess its something stupid like "love of science" or "seeking truth" that motivates them.
On the other side of the debate are (i) a lot of people who know nothing about climate or science, (ii) some bloggers (iii) some politicians (iv) some journalists.
Knowing nothing else about the debate, who would you side with? Seriously. Forget politics and what your neighbor or some fat idiot on the radio says: who would you side with? Let me put it this way, if there were a debate between the Pope and my barber on some fine point of Catholic catechism, I know who I would side with.
Reading the denialist mutterings gets depressing. They go on and on and on. Last argument just got skewered? No problem, here are three more! Thermometers aren't accurate, the wrong kind of paint is used on weather stations, what about clouds?, what about cosmic rays?, computer models aren't accurate, its just natural, its cold today, Antarctic sea ice is growing. Blah, blah, blah. Depressing.
Want to get a little depressed? Read this point-by-point rebuttal to the utter crap put out by the Wall Street Journal. Why exactly is a respected newspaper spreading this kind of pernicious nonsense?
So why do people get so worked up over climate change? I really don't know, but I'll make some guesses:
- Al Gore
- Gore's movie made him the poster boy for climate change and a lot of people really seem to hate him. I guess that because Gore was a Democrat people have associated climate change with some left wing conspiracy or something. (Really, I don't know and can't imagine. If you can answer this submit a comment below). I suppose that if Martin Luther King or Ghandi had made the movie there would be fewer conspiracy theories. And if Reagan or Nixon had made the movie it would be the wacko leftist socialists who would be complaining.
- Its anti business
- I suppose you could argue this, but its pretty damn weak. If Exxon were dumping PCB-laden mercury into your backyard you might complain. But if Consol is dumping CO2 into the atmosphere somehow it is ok? We require hog farmers to pool and mitigate the pig shit their farms produce. We require loggers to replant trees. We require mining operations to contain the chemical pollutants they produce. Somehow all of these businesses manage to survive. There is a cost associated with pumping carbon into the atmosphere. It would be prudent, reasonable, and proper free-market philosophy to charge for this cost. It is worth remembering that it was Nixon who created the Environmental Protection Agency.
Learn for Yourself!
There is a lot of information on climate change out there, so there is really no excuse for repeating or believing climate nonsense. Here are some excellent sources:- IPCC. The official site for the Intergovernmental Panel of Climate Change. Yeah, its part of the UN. Try to get over it.
- realclimate.org, an excellent blog maintained by real climate scientists
- climateprogress.org, a blog from the Center for American Progress Action Fund.
- skepticalscience.com, a dedicated physicist maintains this blog, focusing on the science of climate change.
- A Few Things Ill-considered, another dedicated amateur debunks the deniers.
- a complete online text book on climate physics from Ray Pierrehumbert of the University of Chicago
- there are also a lot of books worth reading. Try one of these
Climate Fear Mongering
A fair amount of nonsense about climate change comes from the other side as well. Climate change, it appears, causes everything from obesity to pygmyism. I will do my best to address these issues as well.
Climate Change may Trigger Earthquakes and Volcanoes.This alarming headline comes to us from the folks at New Scientist, who were reporting from the "Climate Forcing of Geological and Geomorphological Hazards" conference. Apparently scientists from real universities think that increased water depths can increase volcanic activity. Oh, and decreased water depths can increase it too. You can't have it both ways, unless, they argue, changes in water level serve to trigger volcanic activity. Fair enough; it might even be true. But common sense says that if a volcano is sensitive to something so minor as a few feet of extra water (by the way the water has expanded, it doesn't weigh more!) over it, then the volcano must be primed and ready to blow. In other words the water is just acting as a trigger, and the volcano would blow sometime soon anyway. In short, who cares?
Refs:
New Scientist article
Questions and Answers
And finally, on to some of the more common issues that climate skeptics like to raise.
You're part of the corruption of science....and all for MONEY! -MartyI'm not sure how corrupt I am, but if you can tell me how to make money out of this I'd love to hear it!
This is from the APS: "There is a considerable presence within the scientific community of people who do not agree with the IPCC conclusion that anthropogenic CO2 emissions are very probably likely to be primarily responsib le for the global warming that has occurred since the Industrial Revolution." -MartyYou can't mean the American Pain, Philatelic, or Psychological Societies, so you must mean the American Physical Society. Here is what their web site actually says:
National Policy
07.1 CLIMATE CHANGE
(Adopted by Council on November 18, 2007)
Emissions of greenhouse gases from human activities are changing the atmosphere in ways that affect the Earth's climate. Greenhouse gases include carbon dioxide as well as methane, nitrous oxide and o ther gases. They are emitted from fossil fuel combustion and a range of industrial and agricultural processes. The evidence is incontrovertible: Global warming is occurring. If no mitigating actions are taken, significant disruptions in the Earth’s physical and ecological systems, social systems, security and human health are likely to occur. We must reduce emissions of greenhouse gases beginning now.
Your statement, “Climate change is real and it is certainly caused by us” is a little strong and yet vague, since much of climate change is certainly caused by forces beyond our control. -anonI agree, much of climate is beyond our control, but there is an additional amount caused by us. That is what I am talking about.
Concerning cooling effects from fossil fuel, I was thinking more about smog and soot particles, that currently are covering much of China - they cause cooling. -anonYes. This is what they call aerosols. Their effect can be directly measured from satellites, they ca use cooling, and their effects are taken into account in the climate models. And in case you were wondering, the effect of aerosols is overwhelmed by warming due to CO2.
In the mid and late 70's, major news publications had numerous articles about global cooling and the return of the ice age. How can the globe, in such a short period of time go from global cooling to global warming? -PJAThis one is pretty common. Its true, there were some popular stories in the 1970's warning about a possible new ice age. But these stories were (sensationalistic) popularizations of some scientific speculation based on minimal evidence. Using this episode to argue that scientists don't know what they are talking about now is just bombast.
Refs:
RealClimate.org
SkepticalScience.com
RealClimate.org more coverage
Since it's difficult to project what is happening on a short term basis, why should we have faith in any of your long term projections? -PJAThe short term is pretty hard to predict, but I am concerned about the long term. Here's the point: predicting long term trends is much easier. The reason is that the long term temperature of the Earth is determined by how much energy it receives from the sun and how much of it is kept in by the insulating effects of the atmosphere. The details that drive short-term weather are irrelevant.
Since you contend that the globe is warming, what would you consider the optimum global temperature, and how did you arrive at this conclusion? -PJAGood question. And not one that I intend to answer or will pretend to know the answer to. My point is that it is warming and this will change things. We as a society will have to decide if (1) this is bad (2) what we should do about it. But since you asked, my gut feeling is that a 10 degree temperature shift over less than a century will cause a lot of headache and misery.
Refs:
You can find out a lot more
on predicted changes due to temperature rise at the IPCC web site.
Ice core data show a lag between CO2 levels and temperature, with CO2 800 years behind temperature. -anonThe implication here is that if CO2 didn't cause temperature change in the past, why should it now? But this is a red herring. Temperature change can be caused by many things. In the past it may not have been caused by rising CO2, and in fact rising temperature caused atmospheric CO2 levels to rise (melting permafrost, bog heating, ocean outgassing). But now the story is different, CO2 is rising and it does cause higher temperatures.
Refs:
SkepticalScience.com
Its been getting colder since 1998. -anonI've heard this a lot. As we all know, the temperature goes up, the temperature goes down, it pretty random over short time scales. It is entirely possible that the global temperature will shift down for a few years even while it is still going up on the long term. In fact, as a glance at the figure shows, this happened in the 1940s. Notice, however, that it would be foolish to claim that the Earth is cooling simply based on measurements from the 1940s. And by the way, I don't see any cooling at all for 1998-2008.
Refs:
SkepticalScience.com
Freeman Dyson thinks climate change is bunk! -anonFreeman Dyson is a Nobel Prize winning physicist who did his prize winning work on renormalization in quantum field theory in the 1940s. Does this make him a climate expert? Nope, not even close. But never mind; let's stick to the facts. Here is what he actually says:
My first heresy says that all the fuss about global warming is grossly exaggerated. Here I am opposing the holy brotherhood of climate model experts and the crowd of deluded citizens who believe the numbers predicted by the computer models. Of course, they say, I have no degree in meteorology and I am therefore not qualified to speak. But I have studied the climate models and I know what they can do. The models solve the equations of fluid dynamics, and they do a very good job of describing the fluid motions of the atmosphere and the oceans. They do a very poor job of describing the clouds, the dust, the chemistry and the biology of fields and farms and forests. They do not begin to describe the real world that we live in. The real world is muddy and messy and full of things that we do not yet understand. much easier for a scientist to sit in an air-conditioned building and run computer models, than to put on winter clothes and measure what is really happening outside in the swamps and the clouds. That is why the climate model experts end up believing their own models. -Freeman DysonIgnoring Dyson's name calling, what he is saying is that the models cannot get all the details of climate change right. True, but sometimes you don't need all the details. Forget about clouds and bogs and all of the other red herrings that the climate deniers throw up. There is more CO2, more CO2 means a warmer planet.
Refs:
NY Times hagiography
blogging Dyson
Atmospheric CO2 already absorbs all the radiation it can, so adding more will do no harm. -anonGetting this one right is a little complicated. For details see the link below. The gist of the argument is that CO2 saturation can happen, but we ain't close to the levels needed yet.
Refs:
RealClimate.org. A detailed discussion of CO2 and the atmosphere.
Science has been wrong before.This is common sentiment, but I am afraid that this is all it is. Scientists have been wrong before, but science as a whole has almost never been wrong, at least not in the way implied by this criticism. For example, in the past scientists believed in Newtonian gravity, and now we know that it is really Einsteinian General Relativity. But the old Newtonian theory wasn't wrong, it just wasn't as widely applicable as Einsteinian gravity is. The theory had evolved and attempts to make it even more widely applicable continue today. The same can be said for the theory of heat and the theory of electromagnetism (and, come to think of it, every theory ever invented).
On the other hand, for the climate change science to be wrong it would require that a global majority of climate scientists are mistaken about factual information. This would be unprecedented in all history. Needless to say, I regard the odds as very small indeed.
The predictions are only based on computer models.True, but don't let the word "model" fool you. A model in this case is a mathematical representation of the Earth, its oceans, and its atmosphere. The inner workings of these systems are based on old and extremely well-understood physics. And they have been tested and tested again against real world climate measurements and laboratory experiments.
How well do the models do anyway? Check out the following. What you see are the IPCC predictions for global temperature and sea levels made in 1990. The predictions are the dashed lines (representing various coal burning scenarios); the grey areas are the errors in the predictions. As you can see, the predicted global temperature is about right, although the actual temperatures are in the high range of the IPCC predictions (so they underestimated the rate of temperature increase). On the other hand the average sea levels rose by substantially more that the IPCC predicted (this is because the effects of ice melting were not accounted for at the time).
