It’s a shame, really. We’ve been aware of the climate change effect of carbon dioxide for over 100 years. We’ve known for at least 30 years that human-caused increases in CO2 and other greenhouse gases will have a powerful impact on climate within decades. We’ve seen it happen — already. We now know that its effect over the next century will be disastrous. But we haven’t moved an inch toward stopping what will bring disaster on our own heads.
It’s like knowing all about the tremendous harm from smoking cigarettes, but still inhaling three packs a day.
This is genuine knowledge, not just some flimsy theory and not uncertain science. Sure there are uncertainties, plenty of them, enough to make you dizzy. But the reality of global warming, the human cause, and the extreme danger are not among the uncertainties. And I do mean knowledge, all that talk about how it’s not a problem is just people and politicians blowing smoke up your ass. But we haven’t even slowed down. Here’s the latest CO2 data from the Mauna Loa atmospheric observatory:
CO2 is rising faster now that it was just a few decades ago. We can even estimate how the rate of increase is changing, by calculating the difference between CO2 concentration each month, and its value 12 months previously, to figure its annual change:
Clearly the annual change in CO2 concentration fluctuates. A lot. But it’s consistently positive, CO2 is growing. And there’s a trend there as well as fluctuation, an upward trend, because the rate of increase is itself increasing. I’ve superimposed a trend line on the above graph.
One of the factors which influences the fluctuations in CO2 growth is the el Nino Southern Oscillation. Here’s a plot of MEI, the multivariate el Nino index, over the same span of time:
There seems to be some correlation between MEI and the CO2 growth rate. We can investigate this by building a mathematical model of CO2 growth rate as a combination of a linear time trend and the MEI index. We can even include a lag in case the effect of MEI on CO2 growth isn’t instantaneous. Here’s how the model compares to observations:
It’s a pretty good fit — a linear growth trend plus MEI influence accounts for about half the variance of the CO2 growth rate. The lag between MEI and CO2 growth response is about 9 months.
We can also study the residuals, which is what’s left over, i.e., what is not explained by the model:
The biggest, most obvious feature is the pronounced dip in the early 1990s. This may well be due to the cooling influence of the Mt. Pinatubo volcanic explosion, or it may be related to the economic impact of the collapse of the former Soviet Union, or both.
Yet one fact remains, inexorable. CO2 continues to grow, significantly faster now than just a few decades ago. And it will continue to grow over the coming decades. How fast it grows depends on what we, as a global society, choose to do about it.
Some will claim that halting the emission of CO2 and other greenhouse gases will only reduce temperature a tiny bit. They are wrong. More to the point, not halting emissions will increase temperature. A lot more than if we do quit.
It’s time to quit smoking.