For many years now, December has been a month of climate hectoring, and for good reason. Every January, Congress returns, and that means debate on some energy legislation designed to impose an onerous tax burden like the Kyoto Protocol on global warming will commence. This year is no different.
In December, we always see reports about "this year" having been the warmest, or nearly the warmest one we have measured. That's because the earth is warmer than it was 100 years ago, and it is currently on a smooth (but slight) warming trend. As a result, each succeeding year tends to approach the warmest values observed for the last century. To put that in perspective: The earth has been much warmer than it is now for about 95 percent of the last 100 million years.
It's always worth noting that in the last 100 years U.S. crop yields quintupled and life expectancy doubled (so much for the terrors of warming). But there's even more hot air this December, with the release of a new report from the National Academy of Sciences, "Abrupt Climate Change: Inevitable Surprises."
Most of the newspapers dutifully equated climate change with global warming, which is what many on the Academy's panel wanted. It's guilt by association. It's warmer than it was 100 years ago. The National Academy is talking about sudden climate changes. Therefore, global warming must cause `em.
Most reporters haven't taken Climatology 101, in which they would have learned that socially significant abrupt regional climate changes take place when the planet is cooling (the "little ice age," which drove the Vikings from Greenland), when it is warming (the Dust Bowl of the 1930s, which drove a lot of farmers bankrupt) and when global temperature is relatively constant (the sudden shut-off of sub-Saharan rainfall which began in the 1960s, and the resulting famines).
So why is the National Academy wasting its time (and our money) pointing out something that is so absolutely elementary in climate science? As one member of the panel told me, the intent of the report was "to draw attention to a common field of interest [abrupt climate changes] so that they could raise awareness and generate some funding support." "The agencies were looking for something they could wave at Congressional [budget] hearings," he added.
Before shrieking in horror, remember that every scientific endeavor competes for public funding. The way to get attention these days is with media theatrics, such as threatening climate gloom and doom. It's not just climatologists, either. Just read the Washington papers for a few days to get the drift.
In reality, abrupt climate changes, like the ones noted above, have been with us since before we came out of the trees. But research funds don't grow there. When the climate shifts abruptly, ecosystems are impacted--some for better and some for worse. Things change, humans adapt, life goes on. But it requires lots of money to study the phenomena.
Speaking of gloom and doom, soon after the Academy report finishes its news cycle, we will read that 2001 is the second warmest year in "history," at least as history is measured in the 140-year-old record of global surface temperature.
But is it? It's not likely that any of the associated stories will analyze the temperature history in any depth. What it reveals about global warming is more reassuring than alarming. The history shows that surface temperatures continue to rise at a constant, slow rate. This is important because most of our projections for human-induced warming also warm at a constant, rather than an increasing rate. Therefore, if the warming we see is indeed largely caused by humans in recent decades, the rate has already been established and it obviously something that we clearly can live with and prosper under.
The highly respected economist Robert Mendelsohn just wrote a book about this. In "Global Warming and the American Economy" Mendelsohn demonstrates that even assuming warming rates higher than the one already established and entrenched, climate change is a net economic benefit.
If you want to see an area where oodles of research money have gotten us not very far, just look at the temperature history. While 2001 indeed is the second warmest in the surface record, our satellites, which are more accurate (but only have 23 years of record), show it was an average year. Satellites are especially adept at measuring the temperature in the layer from about 5000 feet on up. Is there a climate model in existence that says the surface should warm while the rest of the lower atmosphere does not? The answer is no.
We've been throwing increasing amounts of money at this problem for years now and the fact of the matter is that we still can't tell, literally, which way is up when it comes to climate change. But that won't stop the scare stories of December.