6 Ways Humans Influence the Weather

iStock
iStock

If you've ever spent any length of time on Twitter, you've probably heard a thing or two about humans secretly having the ability to control the weather. While that talent only exists in movies, we humans and our everyday activities do indirectly influence the weather in ways that go far beyond our production of greenhouse gases. Climate scientists and meteorologists have documented these effects for years. 

1. CITIES FORM HEAT ISLANDS.

sunlight shining through city streets and buildings
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They're not exactly wrong when they call the capital of Georgia "Hotlanta." Most populated areas generate heat simply by existing. The dense web of asphalt roads, concrete sidewalks, brick facades, and tar roofs are able to absorb a significant amount of heat from the daytime sun, even in the dead of winter. This human-made insulation, called the urban heat island effect, keeps city centers a tad hotter on hot days and a little less cool on cold days.

While the urban heat island effect might make you think of burning-hot asphalt, it's actually most noticeable during winter storms when air temperatures are hovering right around freezing, putting you right on the line between wet snow, an icy mix, or a cold rain. The artificial warmth from cities can influence the precipitation type in these storms, potentially lowering a city’s snow accumulations compared to its suburbs.

A 2011 study published in the Journal of Applied Meteorology and Climatology [PDF] also found that the urban heat island effect can have a pronounced impact on thunderstorms that form over cities. The researchers studied 91 summertime thunderstorms that formed over Indianapolis, Indiana, and found that their research models could not replicate those thunderstorms without the influence of the urban area beneath the storms.

2. CROPS JACK UP THE HUMIDITY.

wheat crops growing in a field
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If cities can absorb the heat of the day and make it even hotter, you can imagine how the vast swaths of crops that blanket the countryside can also affect our daily weather. Instead of making it hotter, crops can make a humid day unbearable by sending moisture levels almost off the charts on a putrid summer's day.

Corn crops are notorious for pushing dew points—the temperature at which the air reaches 100 percent humidity—up above 80°F in the middle of the summer, creating a dangerous heat index that soars far above 100°F. Compare that to a muggy day, which has a dew point around 70°F, or a comfortably dry day with a dew point in the low 50s.

The harvest can have the opposite effect. In 2016, Mesonet, a network of weather stations in Oklahoma, found that newly harvested areas of wheat in the northern part of the state were hotter and had a lower dew point than their cooler but muggier surroundings.

3. PAVING INCREASES THE INTENSITY OF FLOODS.

multilane highway with heavy traffic
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Our obsession with construction doesn't stop at influencing temperatures. Paving over porous earth with relatively impervious materials like asphalt and concrete has also had a major impact on flooding during heavy rain events. Fewer places for rainwater to escape means that the sudden influx of water builds up in urban areas or runs off and inundates places that had never seen flooding before.

4. NUCLEAR POWER PLANTS CAN TRIGGER NUCLEAR-EFFECT SNOW.

nuclear power plant during the winter
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Lake effect snow is a yearly phenomenon across North America’s Great Lakes, where bitterly cold air flows over the warm lake water, triggering convection that blows ashore as heavy bands of snow. The bands of snow are so intense that communities can see many feet of snow in one day, sometimes accompanied by thunder and lightning.

It's not only bodies of water that can cause this phenomenon. Nuclear power plants release large amounts of steam during the course of their operations, and on cold mornings when there's enough moisture in the air, locations immediately downwind of a power plant's steam stacks can experience "nuclear-effect snow," which forms through similar means as lake effect snow. The phenomenon isn't limited to just nuclear power plants, but they produce enough steam that it’s noticeable over a large area. Thankfully for residents nearby, it doesn't produce much snow—and it’s not radioactive.

5. URBAN DENSITY CAN AMPLIFY WINDS.

girls talking selfie in paris as wind whips their hair around
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If you've ever walked down a city street on a windy day, you’ve probably noticed that it sometimes feels like you're being buffeted by air shot out of an industrial fan instead of a regular windstorm. Dense building construction can amplify the winds and cause gusts to blow much faster than they would out in the open. This wind tunnel effect can cause serious damage, blowing out windows, knocking down trees, and sending dangerous debris hurtling toward the busy streets below.

The principle is the same as holding your thumb over the end of a garden hose to make the water spray out faster—the wind speeds up dramatically as it presses between the buildings. This is also why you should never take shelter underneath a bridge during a tornado. The tornadic winds squeezing underneath the bridge will speed up, increasing the odds that you’ll be pelted by debris or sucked out into the open.

6. JETS CREATE CIRRUS CLOUDS.

plane exhaust in the sky with a foreground of bushes and trees
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The simple act of flying can also create intricate patterns of clouds in the sky that wouldn't have formed had we not perfected the art of air travel. The hot water vapor produced by the engine exhaust of a high-flying jet aircraft leaves contrails, short for condensation trails, in its wake. Contrails can dissipate right away or linger for hours depending on upper-level humidity and winds. These man-made cirrus clouds are most common at high cruising altitudes, but places like the Arctic and Antarctic get cold enough that contrails can form at or near ground level.

Editor's note: This story, which originally ran in 2016, was updated in August 2018.

Turn Your LEGO Bricks Into a Drone With the Flybrix Drone Kit

Flyxbrix/FatBrain
Flyxbrix/FatBrain

Now more than ever, it’s important to have a good hobby. Of course, a lot of people—maybe even you—have been obsessed with learning TikTok dances and baking sourdough bread for the last few months, but those hobbies can wear out their welcome pretty fast. So if you or someone you love is looking for something that’s a little more intellectually stimulating, you need to check out the Flybrix LEGO drone kit from Fat Brain Toys.

What is a Flybrix LEGO Drone Kit?

The Flybrix drone kit lets you build your own drones out of LEGO bricks and fly them around your house using your smartphone as a remote control (via Bluetooth). The kit itself comes with absolutely everything you need to start flying almost immediately, including a bag of 56-plus LEGO bricks, a LEGO figure pilot, eight quick-connect motors, eight propellers, a propeller wrench, a pre-programmed Flybrix flight board PCB, a USB data cord, a LiPo battery, and a USB LiPo battery charger. All you’ll have to do is download the Flybrix Configuration Software, the Bluetooth Flight Control App, and access online instructions and tutorials.

Experiment with your own designs.

The Flybrix LEGO drone kit is specifically designed to promote exploration and experimentation. All the components are tough and can totally withstand a few crash landings, so you can build and rebuild your own drones until you come up with the perfect design. Then you can do it all again. Try different motor arrangements, add your own LEGO bricks, experiment with different shapes—this kit is a wannabe engineer’s dream.

For the more advanced STEM learners out there, Flybrix lets you experiment with coding and block-based coding. It uses an arduino-based hackable circuit board, and the Flybrix app has advanced features that let you try your hand at software design.

Who is the Flybrix LEGO Drone Kit for?

Flybrix is a really fun way to introduce a number of core STEM concepts, which makes it ideal for kids—and technically, that’s who it was designed for. But because engineering and coding can get a little complicated, the recommended age for independent experimentation is 13 and up. However, kids younger than 13 can certainly work on Flybrix drones with the help of their parents. In fact, it actually makes a fantastic family hobby.

Ready to start building your own LEGO drones? Click here to order your Flybrix kit today for $198.

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How to Brew Your Own Fluorescent Beer at Home

The Odin
The Odin

If you're one of the many people who made their own sourdough starter in quarantine, you already know yeast is a living thing. That means its biological makeup can be tweaked using genetic engineering. As Gizmodo reports, that's exactly what a former NASA biologist has done to create his new fluorescent yeast kits.

A few years ago, Josiah Zayner left his job as a synthetic biologist for NASA to found The Odin, a company that lets anyone experiment with genetic science at home. His recently launched yeast kit accomplishes this in an eye-catching way. Thanks to a fluorescent protein from jellyfish, yeast that's been genetically modified with the kit glows green under a black or blue light.

Despite looking like a prop from a sci-fi film, the yeast is still yeast. That means it can be used in home-brewing projects if you want to take the science experiment a step further. According to Eater, yeast made with the kit ferments and fluoresces when added to honey and water. If you brew a batch of beer with the right amount of yeast, the final product will emit an otherworldly glow when viewed under a blacklight. The kit hasn't been FDA approved, but the company states the materials are nontoxic and nonallergenic, and beer made with it will still taste like beer.

You can purchase a fluorescent yeast kit from The Odin's online shop for $169. If you're looking for more ways to experiment with genetic technology at home, the company also sells kits that let you play with frog and bacteria DNA.

[h/t Gizmodo]