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Does the Thunderstorm "Bubble" Really Exist?

Have you ever watched a promising thunderstorm barrel toward you, only to see it fall apart or shift course at the last second? It can be frustrating to expect the cooling relief of a nice deluge—only to be left high and dry as you watch the dark clouds fade away on the horizon.

It’s common to describe this phenomenon as a “bubble,” a perceived forcefield hovering over your town that seems to deflect storms when you want them the most. There’s even an XKCD comic about it. Of course, those mythical deflectors don’t exist, but why do storms seem to consistently hit certain areas, while often skipping nearby towns?

Some local features, like large, cool bodies of water or tall mountains, really can affect how thunderstorms behave. But for the most part, a storm suddenly missing one location is mostly the result of how these bubbling masses of air and moisture evolve throughout their short lifecycle.

There are three common types of thunderstorms—single-cell, multicell (think squall lines), and supercells. The latter two categories are commonly associated with organized severe weather outbreaks. By far the most common type of thunderstorm around the world is a single-cell. This is a small, localized burst of convection often called a pop-up, popcorn, or garden-variety thunderstorm.

If there isn’t a focus point for thunderstorms to develop—something like a cold front or a sea breeze—the exact location where one of these warm weather torrents develops is usually pretty random. A storm will pop up, produce lots of lightning and heavy rain for a little while, and then start to dissipate. The cold air rushing away from the decaying storm will serve as a focus for more thunderstorms to develop nearby. Whether or not you get hit by an approaching thunderstorm depends on how healthy it is, and if any other storms form in its wake. In other words, if a storm falls apart a block away from you, it’s usually a stroke of atmospheric luck.

If you average out precipitation trends over a long period of time, the data show that rainfall is pretty evenly distributed between neighboring communities. One storm could miss you and hit the town next door, while the storm that hits you missed your neighbors down the street. It balances out with time.

However, there are some cases where certain towns benefit from their surroundings when a thunderstorm is on its way. Thunderstorms can start to weaken as they approach more stable air near cool bodies of water like the Atlantic Ocean or the Great Lakes. There is also some truth that mountains are less conducive to storms, as the rough terrain and cooler temperatures can disrupt the updraft and temporarily weaken storms as they traverse the terrain. That certainly isn’t always the case, though—there are plenty of rocking storms along the coast and in the mountains every season.

So for the most part, if a thunderstorm looks like it’s coming straight for you and then disappears into thin air, it has less to do with where you live and more to do with the fragile, fluid structure of these magnificent natural formations.

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Weather Watch
3 Ways We Can (Kind of) Control the Weather, and 5 Ways We Can't

Humans have the incredible ability to control the world around us. We can move mountains and land robots on other planets. We can keep each other alive longer than ever before and even bring entire species back from the brink of extinction. But despite all of our leaps forward, we're still unable to control the weather, a tremendous force that affects every human being on this planet. Still, humans have come up with some pretty crafty ways of influencing the weather—in small doses.

1. WE CAN MAKE IT RAIN … SOMEWHAT.

The desire to control weather has been a mainstay of imagination since, well, the beginning of imagination. The fortunes of entire societies can hinge on flood or drought. We have strong motivation to want to create a rainstorm in one spot or moderate snowfall in another. But the greatest success we've ever had is a technique that can (maybe) encourage a tiny bit of rain to form over a tiny area.

Cloud seeding is a process through which fine particles like silver iodide are released into a cloud in order to encourage the formation of rain or snow. These particulates serve as a nucleus around which water vapor can condense and turn into a raindrop or a snowflake. This is most commonly done with small airplanes, but it can also be accomplished by launching tiny rockets or flares from the ground.

In theory, the practice of cloud seeding could have innumerable uses around the world, including crop maintenance, providing drinking water, and even possibly weakening severe thunderstorms or hurricanes. There's only one problem: It doesn't work all that well.

The effectiveness of cloud seeding is a hot topic of debate among scientists, but most studies have either found negligible impacts on precipitation, or the researchers were unable to determine the exact impact of cloud seeding. Cloud seeding is a great concept if you want to help one cloud produce a little extra rain or snow just to say you can do it, but it's not the way to go if you're desperate and want to trigger a deluge. This process requires the pre-existing presence of clouds, so even if the technology improves in the future, it's not a viable solution for drought-stricken areas that haven't seen meaningful clouds in weeks.

2. WE CAN DEFINITELY ATTRACT LIGHTNING USING ROCKETS.

Lightning safety is one of the things you learn from a very young age. "When thunder roars, go indoors," as the motto goes. We learn to stay away from open areas and water during thunderstorms. But what if you wanted to attract lightning? It's surprisingly easy to do if you have the right equipment and really, really want to encounter some of nature's fury.

Scientists who want to study lightning can bring it right to their doorstep by using specially designed rockets attached to conductive wires that lead to the ground below. When a thunderstorm blows over the observation station, operators can launch these rockets up into the clouds to trigger a lightning strike that follows the wire right down to the ground where the rocket was launched. Voila, instant lightning. Just add rocket fuel.

3. WE CAN CREATE CLOUDS AND HEAT—EVEN WHEN WE DON'T MEAN TO.

Most of the ways in which we control—or, more accurately, influence—the weather is through indirect human actions—often unintentional. "Whoops, the nuclear power plant just caused a snowstorm" isn't as crazy as it sounds. Steam stacks can and do produce clouds and updrafts with enough intensity to create rain or snow immediately downwind. The very presence of cities can generate microclimates with warmer temperatures and heavier rain. And there's also climate change, the process in which our accumulated actions over a long period of time are influencing the very climate itself.

BUT WE CAN'T DO THE FIVE FOLLOWING THINGS.

Despite our limited ability to influence a few aspects of weather over small areas, there are some rather colorful conspiracy theories about whether or not governments and organizations are telling the whole truth about how much we can accomplish with today's technology. There are folks who insist that the trails of condensed water vapor, or "contrails," left behind jet aircraft are really chemicals being sprayed for sinister purposes. (They're not.) There are theories that a high-frequency, high-power array of antennas deep in the Alaskan wilderness can control every weather disaster in the world. (It doesn't.) There are even folks who insist that Doppler weather radar carries enough energy to "zap" storms into existence on demand. (Dr. Evil wishes.)

There are also some bizarre and unworkable theories that are offered in good faith. A meteorologist a few years ago opined on whether building an excessively tall wall across middle America could disrupt weather patterns that could lead to tornado activity. And every year the National Hurricane Center is peppered with questions about whether or not detonating nuclear bombs in a hurricane would disrupt the storm's structure. Unfortunately, while pseudoscience offers up great theories to test in the movies, when it comes to weather, we're still not in control.

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Weather Watch
NASA Figures Out Why When It Rains, It (Sometimes) Drizzles
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What’s the difference between drizzle and rain? It has to do with updrafts, according to new research by NASA scientists into the previously unexplained phenomenon of why drizzle occurs where it does.

The answer, published in the Quarterly Journal of the Royal Meteorological Society, could help improve how weather and climate models treat rainfall, making predictions more accurate.

Previously, climate researchers thought that drizzle could be explained by the presence of aerosols in the atmosphere. The microscopic particles are present in greater quantities over land than over the ocean, and by that logic, there should be more drizzle over land than over the ocean. But that's not the case, as Hanii Takahashi and her colleagues at the Jet Propulsion Laboratory found. Instead, whether or not rain becomes full droplets or stays as a fine drizzle depends on updrafts—a warm current of air that rises from the ground.

Stronger updrafts keep drizzle droplets (which are four times smaller than a raindrop) floating inside a cloud longer, allowing them to grow into full-sized rain drops that fall to the ground in the splatters we all know and love. In weaker updrafts, though, the precipitation falls before the drops form, as that light drizzle. That explains why it drizzles more over the ocean than over land—because updrafts are weaker over the ocean. A low-lying cloud over the ocean is more likely to produce drizzle than a low-lying cloud over land, which will probably produce rain.

This could have an impact on climate modeling as well as short-term weather forecasts. Current models make it difficult to model future surface temperatures of the Earth while still maintaining accurate projections about the amount of precipitation. Right now, most models that project realistic surface temperatures predict an unrealistic amount of drizzle in the future, according to a NASA statement. This finding could bring those predictions back down to a more realistic level.

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