Why the wildfires in Wyoming were not extinguished with…

Wyoming uses cloud seeding as an environmentally friendly way to squeeze a little more snow out of the clouds, increasing the annual snowpack. This puts a little more water into its reservoirs to supply cities and agriculture.

But if this method is truly effective, why isn’t it used to fight forest fires?

Almost from million acres of land burned in a wildfire in Wyoming this year, it’s a question Wyoming residents are asking on many social media sites like Facebook and Twitter.

But in the case of cloud seeding and wildfires, it all depends on the science: what cloud seeding is, and in the case of wildfires, what it is not.

“One very important thing to know about cloud seeding is that in order for it to even have a chance, you need a cloud in the first place,” Cowboy State Daily meteorologist Don Day said. “You can debate whether cloud seeding will help a lot, a little, or not at all, but either way it only works when it rains.”

Cloud seeding cannot cause clouds

Wildfires in Wyoming were largely caused by a lack of clouds that caused rain in the first place.

And this is the main reason why cloud seeding is ineffective in fighting wildfires. This technology could allow more moisture to be gradually squeezed out of the cloud.

But first of all, it cannot cause rain clouds.

This only works when there is a cloud that already has some moisture in it.

This may then be effective in causing the cloud to release moisture. There is also some evidence that cloud seeding techniques can squeeze a little more water out of a cloud than it would release on its own.

But it cannot create moisture from the air. It won’t work where it’s been bone dry for weeks on end.

“If you have clear skies and high blood pressure, you can’t just go up and throw out some silver iodide and expect it to work,” Day said. “That’s just not how cloud seeding works.”

Life of an Ice Angel

Most rain actually begins life in the upper atmosphere, where it is quite cold—much colder than the 32 degrees considered the freezing point of water.

“When liquid water is in the form of small droplets that are smaller than a millimeter, much smaller than a millimeter, it’s actually difficult to freeze those droplets,” University of Wyoming atmospheric scientist Jeff French told Cowboy State Daily. “Sometimes these droplets remain liquid until temperatures reach 15 or 10 degrees Fahrenheit before they freeze.”

These little ice angels made from supercooled water are ready to float forever in the heavens, without ever thinking about falling to the ground.

In fact, unless they start to freeze and clump together, they will simply stay that way until the clouds clear and no rain or snow falls at all.

This is where scientists believe substances like silver iodide could be the party hat-trick, helping all the little ice angels overcome social anxiety and already freeze so they can start sticking together and falling from heaven to earth.

If it’s warm, they melt and turn into rain. If it’s cold, they stay frozen and turn into snowflakes – or maybe sleet or hail, depending on how the little frosty party started.

“But if it’s cold outside and there’s already a lot of natural ice in the cloud, cloud seeding at that point isn’t effective,” French said. “Or if the cloud is really warm, no matter what you add to it, it won’t promote freezing. So there’s a bit of a sweet spot here.”

Further determining the optimal conditions under which cloud seeding can help is the subject of French’s research, something he has been studying for decades.

“In an environment where cloud seeding actually works, we do a pretty good job of it,” he said. “And in an environment where it won’t have any impact at all, we do a pretty good job of it. But there are a lot of issues between these two, yes, and we need to understand them better.”

How effective is still debated

It is still unclear whether cloud seeding works and, if so, to what extent. In fact, there is a huge scientific debate about how effective cloud seeding is and whether it is worth the cost.

The challenge, Day told Cowboy State Daily, is quantifying the results so they can be replicated.

Evidence may suggest that seeding an existing cloud produces progressively more rain or snow, but without a control storm that closely replicates the seeded storm, there is no way to compare results and know exactly how big the difference is. the technique is done.

French, on the other hand, believes it does work in the right conditions and can add up to 10% of snowpack over the course of a season. The key, he says, is to study a specific area to understand its weather conditions. Then figure out where there are opportunities for the existing rain or snowfall patterns.

“Even under the best of circumstances, there won’t be much more rainfall,” he said. “There might be somewhere between 5 and 10 percent more rainfall.”

This may not seem like much, but over the course of the season it starts to add up.

“If you’re talking about a place on the mountain that gets 200 or 300 inches of snow, if another 10% falls, that’s another 30 inches of snow,” he said. “When you combine that with the entire mountain range, throughout the entire season, it makes a difference. Now this is not a transition from drought to abundant water. But this adds another 5-7% water to what is available.”

Wildfire weather isn’t conducive to cloud seeding

That said, French doesn’t believe cloud seeding will ever get to the point where it would be useful for fighting wildfires.

First, its effectiveness depends on studying the specific weather conditions in the region and developing a cloud seeding plan that will produce results. It can’t be done, Johnny is there. Collecting this information takes months, including setting up ground-based cloud seeding guns and verifying the results.

French acknowledged that silver iodide could be delivered to the clouds using aircraft rather than ground equipment, but the aircraft could only operate for an hour or two at a time. This limits the effectiveness of such a campaign compared to ground guns. This also increases its cost significantly.

Additionally, wildfires occur in areas where the whole problem is that there were no rain clouds to work with, meaning there was probably nothing to plant anyway.

“If it had rained in these areas, there wouldn’t be such bad wildfires,” French said.

Forest fires are their own wild card

In the event of isolated rain events, such as the one experienced last weekend from the Elk and Stay fires, rain amounts will be minimal. Cloud seeding lasts for a specific period of time, such as the entire winter season.

“For example, if a cloud drops 2 inches of snow and you seed it, it could fall 2.2 inches,” he said, indicating an added gain of 10% at best. “That extra two inches of snow isn’t going to make a big difference when you’re talking about fighting a wildfire.”

Another challenge to overcome is the fire itself, which can significantly change the nature of things by releasing its own particles into the atmosphere.

This means that additional cloud seeding may not do anything useful. In fact, it may have the opposite effect. If there are too many particles, nothing ever aggregates to the point where it becomes heavy enough to fall.

“Clouds can also be at the wrong temperature and have the wrong character,” he said. “All of these factors need to be considered when you evaluate the effectiveness of cloud seeding or whether cloud seeding will be effective in increasing precipitation.”

Rene Jean can be contacted at [email protected].