The study of the composition or dynamics of the gaseous layers around planets.

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Why is the surface of Venus so hot?

Whenever I have seen Venus described, its high surface temperature is attributed to an intense greenhouse effect. This seems to make sense, as its atmosphere is roughly 96% CO2. But on Earth, the ...
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235 views

Where in the atmosphere is the blue light scattered?

I have searched Wikpedia and the Physics Stack Exchange archieves, and I cannot find the answer to these two related questions. If it is, please guide me to where this information is located. If ...
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The Density of Clouds

Clouds are made up of tiny water or ice droplets, depending on temperature. This implies that cloud density is greater than that of dry air. Why don't clouds sink through their surrounding atmosphere ...
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174 views

Do hail stone fall down just when it is created?

Density of ice is much higher than air. Then how can hail stone remain in earth atmosphere before they fall down ?
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66 views

How can I estimate confidence intervals around the forecasted temperatures for future days?

Weather.com will happily give me temperature predictions for the next ten days, but no indication of how reliable those predictions are. So if I want to plan something for a week from today, or four ...
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908 views

Why does the sun “shine brighter” some days?

Today, the sun seems extremely bright; more dazzling than usual, and even the roads seem to be brighter so it's not just when you look up in the sky. Is more light actually getting through (perhaps ...
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2k views

Atmospheric pressure experiment using a cup with a fluid to hold a glass plate

When I was in high school, my teacher did an experiment to show the power of atmospheric pressure. Experiment: Prepare a glass bottle, fill with water, put a glass plate on the bottle, make sure ...
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147 views

Physical interpretation of the Lorenz system

The Lorenz equations $$ \frac{dx}{dt} = \sigma(y-x);\\ \frac{dy}{dt} = x(\rho-z)-y;\\ \frac{dz}{dt} = xy - \beta z $$ were (I believe) the first set of nonlinear equations known to exhibit chaotic ...
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Why don't different air masses mix immediately?

In meteorology, the atmosphere is considered to be divided into air masses, regions of relatively uniform temperature and humidity with fronts on their borders. But why doesn't the air from different ...
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164 views

Weather forecasting with coffee bubbles

The other day I saw this life-hack: And I was wondering how true it is. First of all, I always thought(listening to weather forecasts) that low-pressure atmosphere is what correlates with rain; ...
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316 views

Keeping air in a giant gravitationally-bound space balloon

Let's say a space-faring society wants to make a space station that has a large volume filled with air (or other gas), but no gravity. Using normal pressure tanks will require gathering an amount of ...
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464 views

Estimating hydrogen loss by Jeans escape

I'm looking at Jeans (thermal) escape of hydrogen from the early Earth's atmosphere. I understand how to calculate the rate in (g cm^-2 s^-1) using the number density, average particle velocity, and ...
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67 views

How about retrodiction, if climate prediction is difficult?

What I mean by the question is if retrodiction has been attempted back to, say, 50 or 100 years starting with the presently known state of climate as initial conditions using the same equations and ...
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83 views

Predominant light frequency over the day?

I'm not well-versed in physics, so I hope you'll forgive me if this question is significantly off the mark. I'm interested in the predominant frequencies of light over the course of one day. My ...
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404 views

Mean optical depth in plane parallel atmospheres

I have the second edition of Houghton's "The Physics of Atmospheres". In section 2.2 he says one can do simple radiative transfer calculations in a plane parallel atmosphere by assuming that there ...
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41 views

Stratospheric ship

Let's assume that we build a giant steel hull in a shape of cube with open top (2km long edge) and lift it to the top of stratosphere and then pump air out of it. Would it float on the outer layer of ...
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How does the atmospheric UVB attenuation of terrestrial planets compare?

On Earth, UVB (280nm - 315nm or 320nm depending on the source) undergoes extensive attenuation through the atmosphere, when observed at the planet's surface, as illustrated below: Image source ...
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288 views

Can a hovering helicopter travel half the globe in 12 hours? [duplicate]

Suppose we have a helicopter that is able to stay stationary in flight for extended periods of time. If such a helicopter stayed at point A in the sky for 12 hours straight, would it reach the other ...
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What does the phrase “limb of the earth” or “atmospheric limb” mean?

What does the term limb of the earth (see this question, for example) or atmospheric limb mean? The phrase strikes me as very odd, since earth is nearly spherical. Do other planets with atmospheres ...
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717 views

Can extra-solar gamma rays reach the Earth's surface?

Can gamma rays of high enough energy entering our planet's atmosphere reach the surface (50% probability)? Or, in other words, is there a window for extremely high-energy gamma rays like for the ...
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132 views

The visibility of air

For pilots of gliders or sailplanes, the 'thermal' is the most important phenomena of the air. A thermal is classically described as an upward flow of air caused by ground level heating of air that ...
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105 views

Why can spacecraft observe terrestrial gamma rays, but terrestrial observers not observe extraterrestrial galactic rays?

For the observation of solar or galactic gamma rays, one should ideally be above the atmosphere. Quoting the Wikipedia article on Gamma-ray astronomy: Most gamma rays coming from space are ...
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121 views

Why does air contain $Ar$ specifically?

Air consists roughly of $N_2$, $O_2$ and $Ar$. Why is $Ar$ the relatively common noble gas compound and not for example the lighter ones $He$ or $Ne$?
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How can I calculate Vapor Pressure Deficit from Temperature and Relative Humidity?

I have a series of measurements of temperature and relative humidity (RH), together with mosquito capture data. Because mosquitoes are sensitive to desiccation, it's reasonable that RH may be useful ...
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31 views

What weathering mechanism leads to reduction of Carbon Dioxide in the atmosphere?

Wikipedia says: The global temperature of the Earth will climb because of the rising luminosity of the Sun, the rate of weathering of silicate minerals will increase. This in turn will decrease ...
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112 views

Do asteroids create sonic boom while entering the atmosphere?

Because of the lack of any materials to propagate sound, it can't spread in space. There's the air in the atmosphere, but its volume mass increases constantly (either linear or exponential, I don't ...
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stability of hypothetical lunar atmosphere

Assume that by some means, the moon could be given an atmosphere, of the same density and pressure at the surface as the earth's. Obviously in a stable atmosphere there are temperature variations from ...
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2k views

How do you calculate vortex shedding frequency?

I am attempting to try to find out if there is any effect of Von Karman vortices on a group of wind speed readings where it is presumed that due to a mountain nearby the data collection spot Von ...
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194 views

Attenuation mass-thickness for sunset light

We are able to look directly at the sun near sunset and sunrise, which clearly demonstrates the fact that our atmosphere attenuates visible light. Let's imagine it follows the typical attenuation ...
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247 views

Do atmospheric physics prevent hot air balloons from ascending over 60,000ft?

I was reading the altitude records for hot air balloons on Wikipedia, and noted that the max hot air balloon altitude was about 60,000ft. It didn't really say if there was a reason why. I know that ...
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337 views

How is the mechanism of greenhouse gases interacting with IR radiation?

How does atmospheric CO2 and other Greenhousgases (GHG) affect the incoming (from sun) and outgoing (from earth) radiation. I understand that at certain wavenumbers (or areas of wavenumbers) in the ...
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What is the reason of the semidiurnal pressure oscillation in the atmosphere?

It appears that in many (most) places on earth, a pressure oscillation of a 100-200 Pa takes place twice a day : that is, with maxima around 12AM and 12PM and minima around 6AM and 6PM. I've found ...
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130 views

Are there convective movements similar to those in clouds everywhere in the atmosphere?

I heard there were powerful convective movements in clouds which were responsible for increasing the size of water droplets or ice crystals. My question is: do the same movements appear outside of ...
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267 views

Hail stones in summer?

This has always puzzled me. Yesterday (in London) it started hailing despite it being about $20^oC$. A couple of years ago I experienced hail in Sicily when it was about $35^oC$ in the shade!. How is ...
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Why the shape of rainbow is semicircular after rain why not the whole atmosphere is colorful?

I have a very simple question. Everyone must have seen the rainbow after rain. According to the theory the rainbow is created due to the passing of sunlight from small drops of water in the ...
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270 views

How many oxygen molecules touch you in your lifetime?

Following up on a comment by BlueRaja to this beautiful answer of Ilmari Karonen, I would like to phrase this follow up question: How many air molecules hit your average human's skin during their ...
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138 views

Can wind currents form in the mesosphere?

Probably not the right forum for this question. How high in the atmosphere may an air-current form? Can a wind current form up in the mesosphere?
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Is CO2 really a potent greenhouse gas for planets around M dwarfs?

The thing with global warming is that it absorbs infrared (IR) radiation from the planet and reradiates much of it back to the planet (whereas the Sun's peak flux is in the visible region, that is ...
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737 views

logarithmic wind speed profile

Under some atmospheric stability condition, over flat terrain, it has been observed for a while that the ratio between wind speed at height $h_1$ above the earth and the wind speed at height $h_0$ is ...
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90 views

Can atmospheric pressure literally push electromagnetic waves?

I work for an IT company and some time ago we had an issue with our wireless internet. We are 5 miles away from the ISP's antenna. Our Sys Admin expressed the view that the electromagnetic waves are ...
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Assuming that the Sun wouldn't evolve into a red giant, how long would the Earth's atmosphere last?

It's not going to last forever - Jeans Escape is going to eventually act on the atmosphere after trillions of trillions of years: see http://faculty.washington.edu/dcatling/Catling2009_SciAm.pdf
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154 views

Keeping air in a well

Let's say I've got an Earth-like planet with no atmosphere: it's just a barren ball of rock. I want to live there, but I don't like domes, so instead I'm just going to dig a big hole and let gravity ...
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658 views

Altering Venus rotational speed to match Earth's via weather manipulation

Venus rotates approximately 6.5 km an hour Earth rotates approximately 1650 km/h how fast could we speed up Venus's rotation via only weather manipulation ( maybe a giant fractal lens between Venus ...
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102 views

Jupiter: Zonal Jets in opposite directions

I recently read that the Great Red Spot arises from the shear instability of zonal flow from zonal jets travelling in opposite directions. Is there any reason why such zonal jets travel in opposite ...
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How does a change in temperature affect relative humidity

Assume that the air pressure and the amount of water in the air stay constant. How can I figure out how much a change in temperature affects the relative humidity?
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120 views

Reference request: statistical inference with real world (chaotic) data, e.g. climate/weather data

I'm interested in the process that goes from, for example, huge data sets of temperature, pressure, precipitation etc readings to a model of the atmosphere. I'd like to know about how much relies on a ...
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83 views

Local real-time lightning tracker site?

Is there a site that tracks lightning strikes at a local level in real-time? Google results for "lightning tracker" yield several sites, but none do this. It seems easy enough to set up. Have ...
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1answer
82 views

image distortion when taking a picture from space

I'm trying to understand if there is a distortion of an image taken from space (i.e. from a satellite), and if there is, then how to model it mathematically (depending on the angle in which we take ...
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For the long-term evolution of atmosphere/orbit, when is perihelion more important than mean distance?

When we want to figure out the long-term evolution of a planet's atmosphere/orbit, when is perihelion more important than mean distance? E.g. some processes (like Jeans Escape and escape of ...
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620 views

x-ray interaction with atmosphere

Why x-ray are stopped by atmosphere while they are more energetic than UV or IR? They certainly interact with atmosphere but I can't understand which phenomenon stop them.