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Quantumaniac is where it’s at - and by ‘it’ I mean awesome.

Over here I post a ton of physics / math / general interesting posts in an attempt to make your brain feel good. My aim is to be as informative as possible, all while posting fascinating things that hopefully enlighten us both a little to the mysteries of our truly wondrous universe(s?). Plus, how would you know if the blog exists or not unless you observe it? Boom, just pulled the Schrödinger’s cat card. Now you have to check it out - trust me, it said so in an equation somewhere.

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The Most Amazing Thing You’ll See Today

Stop whatever you are doing, make this full screen, and prepare to be awed: This time-lapse video of a supercell storm cloud rotating over Texas is far and away the most amazing thing you’ll see today.

Yes, that’s real.

A supercell is a rotating thundercloud; the spinning vortex in the middle is called a mesocyclone. Conditions need to be just so to create one. First you need a wind shear, where wind blows faster in one spot than another, so a blanket of air is flowing over another one. This sets up a rolling vortex, a horizontally-rotating mass of air like the way a wave breaks when it gets to a beach. An updraft then lifts that vortex, which then spins vertically.

The warmer air in the vortex rises; this is called convection. If there’s a boundary layer of air above it, called a capping layer, it acts like a lid, preventing the vortex air from rising. It builds up power, and can suddenly and explosively grow to huge size. Wikipedia has a good description and diagrams of how this works.

Supercells generally form where there’s a lot of flat land to get that good horizontal flow first. Texas has that in abundance, which is why photographer Mike Olbinski went there, in hopes of getting footage like this (read his description of his adventure on the Vimeo page for the video; it’s quite good). Texas, it so happens, is roomy, so it took him four years to be at the right spot at the right time—in this case, June 3, 2013. Persistence paid off for him, and because he shared this terrifying beauty, it paid off for all of us. Olbinski has several other incredible stormchasing photos on his website.

I’m fascinated by weather phenomena, and supercells like this are something I’d love a chance to see from close by… but not too close by. They can create havoc locally, with torrential downpours (that look like alien spaceworms blasting the Earth), severe lightning, and tornadoes. Given that, maybe video like this is satisfying enough for now.

Source: Slate

Why All Hurricanes Look the Same from Space
Every satellite photo of a hurricane looks a lot like the last one. The images above, taken with NASA Goddard Spaceflight Center’s MODIS instrument aboard the Terra and Aqua satellites, are a case in point.
The striking similarity has to do with how hurricanes form, said meteorologist John Knaff of the National Oceanic and Atmospheric Administration. Hurricanes are a type of tropical cyclone, a rotating system of thunderstorms and heavy winds. They form over warm ocean water near the equator. When warm, moist air rises, it creates a low-pressure area in its place, which sucks in more warm air from nearby. The moist air cools as it ascends, condensing to form clouds. The warm air keeps cycling upward like a giant chimney, coiling the clouds into a swirling mega-storm.
In the northern hemisphere, hurricanes always spin in a counterclockwise direction, whereas in the southern hemisphere, they spin clockwise. The reason is that as the warm air rises, the Earth’s rotation creates a Coriolis effect. It’s a bit like trying to draw a straight line on a spinning record — the line will end up curved.
“If the Earth wasn’t spinning at all, winds would blow from high pressure to low pressure,” Knaff said. But because the Earth is spinning, “It causes winds in the northen hemisphere to rotate counterclockwise and the winds in the southern hemisphere to rotate clockwise around low pressures.”
Hurricanes need a reservoir of warm water to fuel them, which is why they only form in lower latitudes. Often they’re caused by “easterly waves” off Africa, small weather systems triggered by the continent’s heavy summer rains. During the summer months, these weather patterns are created every few days.
Once a hurricane has formed, there are several things that can kill it. When you have different wind speeds at different altitudes, known as vertical wind shear, “that kind of knocks the storm over,” Knaff said. As storms migrate northward, another hurricane-stopper is cold water, which lacks the heat energy to keep driving the storm. And when a hurricane hits land, the same thing happens.
When scientists track hurricanes by satellite, they look for features that provide clues about the storm’s strength. For instance, ones with an eye are stronger than ones without, and ones with greater curvature are stronger than ones with less curvature.
So although hurricanes may appear similar at first glance, Knaff said, “They do look different in satellite pictures to a trained eye.”

Why All Hurricanes Look the Same from Space

Every satellite photo of a hurricane looks a lot like the last one. The images above, taken with NASA Goddard Spaceflight Center’s MODIS instrument aboard the Terra and Aqua satellites, are a case in point.

The striking similarity has to do with how hurricanes form, said meteorologist John Knaff of the National Oceanic and Atmospheric Administration. Hurricanes are a type of tropical cyclone, a rotating system of thunderstorms and heavy winds. They form over warm ocean water near the equator. When warm, moist air rises, it creates a low-pressure area in its place, which sucks in more warm air from nearby. The moist air cools as it ascends, condensing to form clouds. The warm air keeps cycling upward like a giant chimney, coiling the clouds into a swirling mega-storm.

In the northern hemisphere, hurricanes always spin in a counterclockwise direction, whereas in the southern hemisphere, they spin clockwise. The reason is that as the warm air rises, the Earth’s rotation creates a Coriolis effect. It’s a bit like trying to draw a straight line on a spinning record — the line will end up curved.

“If the Earth wasn’t spinning at all, winds would blow from high pressure to low pressure,” Knaff said. But because the Earth is spinning, “It causes winds in the northen hemisphere to rotate counterclockwise and the winds in the southern hemisphere to rotate clockwise around low pressures.”

Hurricanes need a reservoir of warm water to fuel them, which is why they only form in lower latitudes. Often they’re caused by “easterly waves” off Africa, small weather systems triggered by the continent’s heavy summer rains. During the summer months, these weather patterns are created every few days.

Once a hurricane has formed, there are several things that can kill it. When you have different wind speeds at different altitudes, known as vertical wind shear, “that kind of knocks the storm over,” Knaff said. As storms migrate northward, another hurricane-stopper is cold water, which lacks the heat energy to keep driving the storm. And when a hurricane hits land, the same thing happens.

When scientists track hurricanes by satellite, they look for features that provide clues about the storm’s strength. For instance, ones with an eye are stronger than ones without, and ones with greater curvature are stronger than ones with less curvature.

So although hurricanes may appear similar at first glance, Knaff said, “They do look different in satellite pictures to a trained eye.”

(Source: Wired)