Saturday, July 5, 2008

Step by step to Global Warming: What is, was, and will be

In my earlier post, ”Troglodytes have feelings, too”, I explained that I’m a Global Warming skeptic and talked about a couple of feeling - as opposed to scientific and philosophical misgivings - that make it impossible for me to just believe in and accept Global Warming. (It looks like Penn Jillette is in a very similar boat. It’s always nice to have company.)

Now I want to lay out those scientific and philosophical misgivings about Global Warming. A big part of my problem is simply the number of separate beliefs I would have to hold in order to make it to full-blown Apocalyptic Anthropogenic Global Warming so I’ll examine each of those beliefs in turn.

Wikipedia defines Global Warming thus:

Global warming is the increase in the average measured temperature of the Earth's near-surface air and oceans since the mid-twentieth century, and its projected continuation.

There’s a lot of complexity hiding in that simple definition. Ask someone, “Do you believe in Global Warming?” If the answer is “Yes” there’s a tendency to think that implies belief in full-blown Apocalyptic Anthropogenic Global Warming. As in, humans are causing it, we’re all going to drown, and we better get busy doing whatever it takes to fix it. If the answer is “No” there’s a tendency to think that implies a lack of belief that the Earth is even getting warmer. Such a lack of belief renders any discussion of antecedent causes and subsequent consequences not just unnecessary but positively pointless.

In truth, however, there is a ladder of steps from someone like William Gray who doesn’t believe the planet is permanently warming to someone like Al Gore who holds the most serious view of the problem and advocates some heavy-duty solutions. Each of us can jump off at any point along the way which leaves the question of belief in Global Warming looking less like a binary problem and more like a sliding scale.

So what steps make up the ladder of Global Warming? I’m glad you asked. To be a full-fledged Global Warming believer you must believe:

1) The planet is getting warmer.
When I first outlined these steps a year ago in an email to a friend, if you wanted to dispute this you talked about measurement problems: urban heat islands, badly placed monitors, missing temperatures from cold countries, and so on. You can still do so - Climate Audit is doing yeoman work on these issues. Now, however, if you don’t want to wade through all that boring technical stuff, you can just point to graphs of the global temperature metrics which have been cool to Global Warming for about 10 years and downright chilly for the last year.

2) The warming is unprecedented in human history.
This is mostly what the Hockey Stick sought to show. It was prominently featured in the IPCC 2001 report. The first controversy swirling around it arose because it wiped out the Medieval Warm Period (and the Little Ice Age for that matter). Then questions arose about the data and the programming. Is the Hockey Stick valid? Depends on who you ask.

3) The warming is caused largely by human activity.
This means it’s not El Nino; it’s not a naturally repeating cycle; it’s not volcanos; and the sun isn’t doing it. Of these, the idea that the sun did it is taken the most seriously by Global Warming believers (although that means they just spend more time saying it doesn’t matter). Why does the sun get extra attention?

Well, remember the Little Ice Age that the Hockey Stick disappeared? That occurred during the Maunder Minimum. A Minimum in this sense is a period of very, very low sunspot activity; this particular Minimum was named after its discoverer, Edward Maunder. There are also Maxima and one of those coincides to some extent with the Medieval Warm Period. More sunspots, warmer earth; fewer sunspots, colder earth? Depends on who you ask. And the answer might be kind of important because although sunspot counts have been high since 1900, our current sunspot cycle (Cycle 24) is late, late, late.

4) The human activity that is causing the warming is the production of greenhouse gases.
In other words, it’s not just that there are more people and more cities making the Earth warmer. It’s a particular thing produced by those humans that is responsible.

5) The greenhouse gas responsible for the greatest part of the global warming is carbon dioxide.
Other greenhouse gases like nitrous oxide and fluorocarbons are not important enough to rate much concern. Methane is getting more attention but CO2 remains the 300-pound gorilla of greenhouse gases. (Water vapor is the by far the most prevalent greenhouse gas but is not considered in this context since it is not caused by human activity.)

These are the Global Warming beliefs that have to do with the past and present. They make up the picture of what Global Warming is and what causes it. They imply the future contained in that last little phrase in Wikipedia’s definition: “and its projected continuation.” Global Warmists believe that so long as humans keep producing enough CO2 to increase the amount of CO2 in the atmosphere, the Earth will continue to warm.

Obviously, I have problems accepting some of these beliefs. But what if you don't? Fine, you say, I’m with the Global Warmists so far, believe it all, no problem. The Earth has gotten warmer and will continue to get warmer still. I like beaches, I hate shoveling snow. So why is this a problem? That’s the question I’ll address next in “Step by step to Global Warming: What lies ahead”.

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