This is turning out to be one of those weeks where all manner of unexpected headlines are popping up in the news. For example, I certainly didn't expect to learn that the state legislature in Tennessee had passed a bill banning chemtrails. That's not exactly what the legislation is intended to do, but NBC News couldn't resist pouncing on it to make the Republican majority there sound like a bunch of loons who follow conspiracy theories. The bill actually places limits on what has come to be known as geoengineering, or the concept of modifying the atmosphere to combat climate change. And one method currently under discussion does look a lot like chemtrails. More on that in a moment.

The Tennessee state House of Representatives passed a bill Monday designed to prevent geoengineering, the practice of intentionally modifying the atmosphere to counteract global warming.

The bill, which had already passed in the state Senate, covers a variety of technological interventions. They include theoretical ideas about cooling the climate by an approach known as solar radiation modification, as well as more limited practices that affect the weather, like cloud seeding, a technique used to increase rain and snowfall. 

Most geoengineering options are theoretical and untested. Federal researchers have taken only a few small steps toward studying their feasibility, and atmospheric scientists say there is no evidence of any large-scale programs.

To be fair, the Tennessee legislators did leave themselves open to a bit of mocking. For one thing, most of the geoengineering technologies covered by the bill either don't exist yet or are in the nascent stages of development and may never be able to be deployed on a broad scale. Further, more than a few of the legislators voting for the bill did make direct references to chemtrails while discussing the bill, or at least comments that sounded awfully close to it. Republican Senator Frank Nicely complained to reporters about the number of trails visible in the sky, saying, "For years they denied they were doing anything.” Assuming this bill becomes law, "they" (whoever that might be) won't be doing it over Tennessee. 

There are two general types of geoengineering being heavily promoted by climate alarmists these days but they represent very different approaches. One is referred to as "solar radiation modification," which is a fancy way of saying that we need to block more of the sun's rays from reaching the planet's surface. One proposed technique would involve sending up planes to spray clouds of fine particles that would supposedly block some of the sun's light. (That's where the chemtrail theory comes in.) What that method's proponents never seem to explain is how we're supposed to prevent those particles from eventually falling back to earth. Gravity is a harsh mistress, after all.

The other method would involve directly decarbonizing the atmosphere. Of course, nobody has really come up with an efficient way of doing that aside from planting a lot more trees, which do it naturally. And all of this effort is being put toward eliminating a gas that only makes up 0.04 percent of the atmosphere. It's also worth reminding the alarmists that the 0.04% in question is the only thing keeping all of the plants alive. And without plants, pretty soon you won't have people. But perhaps that's been their goal all along.

The chemtrails theory has been around for a long time, at least since 1996. It's proven to be very durable. And don't get me wrong here... I love a good conspiracy theory as much as the next guy. (I'm "the UFO guy," after all.) But there has simply never been any evidence offered to support the idea that the trails left in the sky by jet aircraft are anything other than condensed water vapor produced by the heat of the jet engines and perhaps a very small amount of engine exhaust. They don't persist very long, they aren't blocking much sunlight, and they aren't being used to conduct government mind control experiments. Or at least I hope they aren't. Given the current state of our federal government, you really can't put anything past these people.