Starship Asterisk*

At last, I am able to tell you why you haven’t heard from me since August. It’s [b]that[/b] thing in this APOD.

I am currently visiting family in the states, but it’s soon back to the land of no Internet and limited mobile.

I wonder if his house survived. Even without GW though, that's been a risky place to own a home. The amount of time it's going to take to prove this guy wrong will be enough he'll be dead. Maybe if he is so sure about it he'll will his great-grandchildren the house and they'll have a nice piece of ocean floor to wonder about.

[youtube]https://www.youtube.com/watch?v=Klgp_qDiRhQ[/youtube]

[quote="neufer"]

Heating due to water vapor condensation produces a high pressure center with outward flow in the [b][u]upper[/u][/b] troposphere.

This is compensated for by a low pressure center with inward flow in the [b][u]lower[/u][/b] troposphere.

The eye wall occurs where centrifugal force from spin up of inward flow just cancels the low pressure in the lower troposphere.

Damp air can only get into the eye by first rising, dumping its water vapor as rain and then falling in from the top as warm dry air.[/quote]

Put it to music and you've got a new dance craze.

[quote="ronterf"]

The spinning cylindrical force is spinning the heavy wet air outward while cooler air from above is falling into the void thus creating added outward pressure increasing the eye size. water is the key factor to the hurricane having an eye, that is why they dissipate over land.[/quote]
[b][u]Water vapor condensation[/u][/b] is the key factor to the hurricane having an eye:

Heating due to water vapor condensation produces a high pressure center with outward flow in the [b][u]upper[/u][/b] troposphere.

This is compensated for by a low pressure center with inward flow in the [b][u]lower[/u][/b] troposphere.

The eye wall occurs where centrifugal force from spin up of inward flow just cancels the low pressure in the lower troposphere.

Damp air can only get into the eye by first rising, dumping its water vapor as rain and then falling in from the top as warm dry air.

The spinning cylindrical force is spinning the heavy wet air outward while cooler air from above is falling into the void thus creating added outward pressure increasing the eye size. water is the key factor to the hurricane having an eye, that is why they dissipate over land.

Likewise, Holy Cowabunga! I was going to say great vid, but keep in mind it is already a killer of 20 people, and that number likely will go up. Thoughts are of the Floridians, stay safe. And the Puerto Ricans and the other islanders affected.

"O Grammar!" crater ladle gull historically, "Water bag icer gut! A nervous sausage bag ice!"

"Battered lucky chew whiff, sweat hard," setter bloat-Thursday woof, wetter wicket small honors phase.

[quote="Boomer12k"] Just my lousy opinion...
*[/quote] Your opinion sounds good to me! There are wispy tornados on Mars. And I've watched whirlwinds often in a corner of buildings at my job. There are complex phenomena for which there is no compact explanation - the most interesting being the jets out the poles of both new stars being 'born' and quasars. As our mathematical models of such phenomena improve, one expects the same behavior to emerge, that's all. Just no simple equation for it. Oh and BY THE WAY: is the fact that Irma is hitting Florida caused by our password?

Holly Cowabunga !!

It is a Vortex...they have a more hollow central area...from the spinning...just like whirlpools, and some eddy currents....a whirlwind...dust devil, tornado, etc...
I assume the rising air that goes up over the top also helps the separation, and the formation of the eye... but I don't think is the whole story. Just my lousy opinion...

Awesome video...

:---[===] *

[url=https://apod.nasa.gov/apod/ap170910.html][img]https://apod.nasa.gov/apod/calendar/S_170910.jpg[/img] [size=150]Swirling Around the Eye of Hurricane Irma[/size][/url]

[b] Explanation: [/b] Why does a hurricane have an eye at its center? No one is yet sure. [i]What[/i] happens in and around a hurricane's eye is well documented, though. Warm air rises around the eye's edges, cools, swirls, and spreads out over the large storm, sinking primarily at the far edges. Inside the [url=https://en.wikipedia.org/wiki/Eye_(cyclone)]low-pressure eye[/url], air also sinks and warms -- which causes [url=https://www.youtube.com/watch?v=BHmUx0ylg-A]evaporation[/url], calm, and clearing -- sunlight might even stream through. Just at the [url=https://apod.nasa.gov/apod/ap161009.html]eye's edge[/url] is a [url=https://www.youtube.com/watch?v=eT5K6FR_eVs]towering eyewall[/url], the area of the highest winds. It is particularly dangerous to go outside when the [url=https://www.livescience.com/15805-calm-hurricane-eye.html]tranquil eye[/url] passes over because you are soon to experience, again, [url=http://media3.s-nbcnews.com/i/msnbc/Components/Photos/060516/060516_towergraphic_bcol_11a.jpg]the storm[/url]'s violent eyewall. [url=https://weather.msfc.nasa.gov/sport/]Featured[/url] is one of the most [url=https://wattsupwiththat.com/2017/09/06/the-most-fantastic-eyewall-video-of-a-hurricane-ive-ever-seen-irma/amp/]dramatic video[/url]s yet taken of an eye and rotating eyewall. The [url=https://twitter.com/NASA_SPoRT/status/905169228000583681]time-lapse video[/url] was taken from space by NASA's [url=http://www.goes-r.gov/]GOES-16 satellite[/url] last week over one of the [url=https://en.wikipedia.org/wiki/List_of_the_most_intense_tropical_cyclones]most powerful tropical cyclones[/url] in recorded history: [url=https://en.wikipedia.org/wiki/Hurricane_Irma]Hurricane Irma[/url]. Hurricanes can be [url=https://www.youtube.com/watch?v=dA5qYrboTUE]extremely dangerous[/url] and their perils are [url=http://www.nhc.noaa.gov/surge/]not[/url] confined to the storm's center.

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