The latest environmental conspiracy theory may be the most bizarre yet.

Hurricane Helene’s slow movement through the Carolinas resulted in catastrophic flooding and its death toll has already climbed to number three on the United States tropical storm fatality list. Only Katrina’s 1,392 deaths in 2005, Audrey’s 416 in 1957, and Camille’s 256 fatalities in 1969 have killed more people.

Social media, websites and popular blogs are spreading wild rumors about rescue, clean-up and assistance efforts. Even crazier myths about the storm itself have been spread, most notably that it was a product of intentional man-made weather manipulation intended to wreak havoc upon southern states.

While I’ll let the political writers referee the political silliness, I hope I can help you better understand why the scientific conspiracy theories are so implausible.

Let’s begin with some history of weather modification efforts. In the mid-20th century, in the midst of other efforts to control natural systems, there were attempts to alter the weather. Cloud seeding was the most notable of these programs, as scientists dropped silver iodide, potassium iodide and dry ice into clouds. These chemicals mimic ice crystals and provide condensation nuclei to help form rain droplets.

While seeding could increase precipitation in some circumstances, it was expensive, unpredictable and generally unproductive. Among other factors, it was very difficult to make rain unless you had an adequate amount of moisture in the air mass. No matter how hard one tries, you can’t get much rain out of air originating in a dry place.

Additionally, air typically needs to be cooled to increase condensation (much as “sweat” forms on a glass when a cold liquid is poured into it). This is most often done in the real world by air rising over mountains, being lifted where warm and cold air meet, or when surface air is warmed and rises.

There is no easy (or affordable) way to make any of that happen at the scale needed to make significant precipitation. When you add the complexity and scale of weather systems to the equation, it makes dependable and predictable weather modification next to impossible.

This includes changing the direction of storms, as some have claimed was done with Helene. (The storm’s slowing and resulting heavy rain in western North Carolina was predicted days before, based on upper wind patterns driving the storm.)

It’s easy to understand, then, that scientists long ago realized it was beyond their power to make such modifications to the atmosphere. The National Oceanic and Atmospheric Administration’s Project Stormfury ended in 1983 when it was concluded that making notable and predictable alterations to the weather was unrealistic.

Despite these facts, the internet once again gives rise to the strangest of stories. And this comes back to an idea we have discussed many times before: Look for credible sources of information. If something sounds outlandish, it likely is.

None of the wild claims (including strange interpretations of radar imagery) have been substantiated by anyone with an iota of scientific credibility. Thankfully, folks from both sides of the political spectrum have pleaded for sanity.

“Friends can I ask a small favor?” North Carolina state Sen. Kevin Corbin, a Republican, posted on Facebook. “Will you all help stop this conspiracy theory junk that is floating all over Facebook and the internet. … Please don’t let these crazy stories consume you.”

John Frederick (www.johnjfrederick.com) writes about science and the environment twice a month for the Mirror.