The study of the composition or dynamics of the gaseous layers around planets, often applied to questions on Earth's atmosphere but can be applicable to all planets & moons in the solar system.

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2answers
880 views

Why is there lightning where there are no clouds? [on hold]

Recently my family and I went onto the balcony to observed the stars in the night sky. We started to see flashes in the sky and we realized that it was lightning (non-fork lightning). I looked around ...
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0answers
20 views

Clarification regarding atmospheric opacity

I have taken a look at the related questions Can someone explain to me the concept of atmosphere opacity? and Why can spacecraft observe terrestrial gamma rays, but terrestrial observers not ...
6
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2answers
4k views

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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5answers
1k views

Is the atmospheric pressure the cause of a planet's surface temperature or is it the temperature the cause of a planet's atmospheric pressure?

I heard a climatologist on a talk show saying that one of the widely known arguments used by climate scientists to exemplify what a runaway greenhouse effect could cause to Earth's temperature and ...
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1answer
106 views

What does “downshear” mean?

I occasionally read descriptions such as "downshear of the vortex" in meteorological publications. What does this mean?
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1answer
55 views

Are lighter molecules in the air more affected by earth gravity?

Or: Why are raindrops falling? In vacuum a heavy (big mass) object is attracted by gravity with the same speed as a light object as shown on the moon with the hamer and the feather. But on earth ...
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1answer
63 views

what is the relation between heat capacity and mixing ratio

I am supposed to derive an expression for the specific heat capacity $c_p$ for air with a water vapour mass mixing ratio of $\mu$. The hint is: (Use the fact that $c_p= (\frac{\partial H}{\partial T})...
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2answers
365 views

What is atmospheric stratification?

In the context of atmospheric stability, what are the meanings of stable or unstable stratification? What is stratification?
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2answers
4k 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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0answers
19 views

Change in volumetric energy density

I we have an insulated system (i.e. $dQ = 0$, where $Q$ is the heat), then the first law of theormodynamics says $$dU = -pdV.$$ If there system changes volume while there are no other sources of ...
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2answers
38 views

Why would El Niño affect atmospheric CO2 measurements?

Starting with this article in Gizmodo: El Niño Has Pushed Our Planet Past a Major Climate Milestone and then to this commentary in Nature Climate Change El Niño and a record CO2 rise there seems to ...
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0answers
26 views

Sky color of a proterozoic earth with a Canfield ocean [migrated]

What would sky color be with a Proterozoic earth during the "Boring Billion (1.8 By-0.8 By) with a Canfield (Euxinic) ocean and a high atmospheric concentration of colorless hydrogen sulfide and very ...
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3answers
1k views

Could the sky on a planet theoretically be any color?

The sky on the Earth is blue. Could the color of the sky on a planet with an atmosphere be of any color theoretically? Which colors are the most likely? I think it would be really awesome to have ...
-1
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1answer
56 views

Is aviation exhaust the culprit for climate change? [closed]

The ongoing climate change is the biggest threat to the human civilization. The recent 4-year drought in California, other droughts and floods in different parts of the world are posing serious ...
10
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2answers
103 views

Why does a rolling thunder always starts with a high pitch and ends with a deep, low sound? [duplicate]

Rolling thunders always come cracking in with a high frequency, and the sound grows more deep as the rolling advances, ending with the deep sound of a roaring lion. Why? This is not the same question ...
11
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3answers
527 views

Extended sound of thunder

Why does the sound of thunder last several seconds even when lightning lasts for only fraction of a second?
3
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0answers
19 views

Ionospheric electron density measurements

I've been working on measuring total electron column density (TEC) with multi frequency GPS data. In theory, signal delay caused by TEC differences should affect the code and carrier nearly evenly in ...
0
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0answers
35 views

Ultra-cold gas giant atmospheres

In the troposphere, which has the bulk of the atmospheric mass, it's colder at higher altitudes due to adiabatic lapse. Gas giants have several different chemicals that condense into cloud decks at ...
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0answers
13 views

Generic Rayleigh effect experiment - nothing happens for water

On youtube, a bunch of Rayleigh scattering experiments (e.g this one are set up with some compound being added to water in order to invoke the effect. Why is there no Rayleigh effect for "pure" water?...
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0answers
23 views

Why are cirrus cloud those that contribute the most to climate forcing?

I read everywhere that most of the forcing produced by clouds is done by cirrus but I can't figure out why. It's obviously related to their IR absorption - emission...
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4answers
2k views

Difference between sunrise and sunset?

Other than knowing which direction is east and which direction is west, or observing for a sufficient timespan (to determine the direction of motion), is there any way of telling whether what one is ...
6
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2answers
170 views

Expression for Atmospheric Pressure with Altitude, including Tidal Forces

Is this simple to obtain? I've tried to modify the constant-gravity model to use the $GM/r^2$ form instead, but my result was shown to be wrong with some testing. Constant Gravity Model You can ...
1
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1answer
18 views

Albedo and radiative forcing

I'm a bit confused on the definitions of radiative forcing and albedo. Consider this textbook problem. Suppose that the albedo of the earth increases by 0.01 in 265 years, ie $A(t) = 0.300+\frac{0.01}...
108
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11answers
21k views

Is the butterfly effect real?

Is the butterfly effect real? It is a well known statement that a butterfly can, by flapping her wings in a slightly different way, cause a hurricane somewhere else in the world that wouldn't occur if ...
16
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2answers
8k views

Is there an upper frequency limit to ultrasound?

Wikipedia has this diagram of the acoustic frequency spectrum: Is there an upper limit to the frequencies you can transmit through the air? Are they absorbed more and more at higher frequencies, ...
11
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5answers
5k views

How does humidity affect the path of a bullet?

Background Last night, I was reading the FM 23-10 (The U.S. army official field manual for sniper training), and I've noticed that they're potentially teaching snipers incorrect information. ...
11
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3answers
442 views

What is the safe distance to a supernova explosion?

In other words, what stars near the Sun may have an impact on the Solar system equilibrium or the Earth life if they become supernova ? Is SN 1987 A too far ?
3
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2answers
505 views

How does rogue planet PSO J318.5-22 stay 800ºC?

According to this article, the rogue planet (meaning a planet which does not orbit a star) PSO J318.5-22 has a surface temperature of 800ºC and weather that features molten iron rain. Without a star ...
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0answers
20 views

Velocity Profile of the Upper Atmosphere

Consider an Earth-Centered Inertial (ECI) frame in which the tangential (to Earth's surface) velocity is measured. Now consider obtaining constant average velocity profiles of the atmosphere as a ...
5
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2answers
2k views

Why does the Sun turn red near sunset?

At daytime the Sun's light is yellowish if not near white. Why when the Sun starts to go down that it's light turn more red. I don't think the earth's rotation is so rapid to cause a red shift. Why ...
16
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4answers
10k views

How Earth protected from the gamma rays generated by Sun?

Sun is generating energy by nuclear fusion. And nuclear fusion will emit energy in the form of gamma rays. Normally earth's ozone filtering the Ultraviolet radiation. And magnetic fields of earth ...
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2answers
59 views

How fast could you suck up the atmosphere [closed]

So kind of a strange question, but if i had a 1000 foot wide hose with endless storage space, whats the quickest possible time it could be used to suck up the entirety of the Earth's atmosphere. Edit:...
2
votes
2answers
10k views

If blue light has a higher energy than red light, why does it scatter more?

As $E=hf=\frac{hc}{\lambda}$, blue light - with a smaller wavelength - should have a higher energy. However, it is the case that blue light scatters the most. Why is it that higher energy rays scatter ...
1
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1answer
53 views

Would 10 metres of liquid air be as effective against cosmic radiation as Earth's atmosphere? [closed]

Assuming ballpark figures which give a depth of 10m if the Earth's atmosphere was liquefied, would that be as effective a protection against ionizing radiation from space as the gaseous atmosphere is?
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1answer
25 views

Why Nitrogen is still (almost) 3 times as abundant as Oxygen in Troposphere? [duplicate]

I learned that our atmosphere has ~78% Nitrogen and ~21% Oxygen. If I fill a glass with 21% water and 78% Canola Oil, the more dense (and thus heavier) water will take a full bottom later and Canola ...
1
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0answers
54 views

Maximum temperature possible on earth

What is maximum temperature that can we have on earth on a single day? Lets say an air mass is static over an area and there is no way for air mass to move, sun warming it up would increase ...
7
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4answers
274 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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1answer
38 views

Atmospheric pressure question [closed]

I'm asked to find at what altitude atmospheric pressure falls to 10% of the mean sea level value. I have found the expression for the variation of pressure with altitude to be $$p = p_0e^{-h \over a}$...
3
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2answers
74 views

Ideal gas equation and atmosphere of Venus

I'm teaching myself some basics of the ideal gas law and working out simple density equations for atmospheric gases at various altitudes. When I applied the gas law to Venus' atmosphere at its ...
3
votes
2answers
2k views

Why is the atmosphere transparent in the visible spectrum?

One of the great 'coincidences' in physics is that the Sun happens to shine most brightly at exactly the wavelengths our eyes can see; it's an easy explanation that our eyes evolved to make the most ...
1
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2answers
36 views

How to combine albedos

I have estimations of the Earth's surface albedo for a region (0.13), as well as an estimation of the atmosphere albedo (0.3 at a solar zenith angle of 1 rad). My question is, how do I find the ...
4
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3answers
1k 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 ...
2
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2answers
7k views

Why is England so cloudy?

Why, physically, some regions of the globe are affected by a noticeable cloudiness respect to others? Is the reason why some places are also rainy the same?
6
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5answers
7k views

Why is the sky of the moon always dark?

Why is the sky of the moon always dark compared to the sky of the earth, doesn't it have day and night like earth?
0
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0answers
20 views

If Earth's atmosphere would be cooled, how would its pressure change relative to its temperature?

I have a feeling it would not behave like an ideal gas? For example, if the atmosphere were to cool down at a constant 1 atm to 90 K, oxygen would liquefy. If changing of pressure would be considered,...
4
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1answer
54 views

Why does the composition of the air does not change with altitude?

Air contains about 78% nitrogen and 21% oxygen independent of altitude (up to 100 km). Why is this? Shouldn't the concentration of nitrogen increase with higher altitudes since nitrogen has a lower ...
0
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1answer
80 views

What height is atmospheric pressure half that at sea level?

$PV = NT$, where T is a constant $P = \rho g h$ but I don't think this equation can hold in this form as the density is most definitely not constant as we go up in the atmosphere $\rho = \frac{M}{V}$...
1
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3answers
789 views

How can planes land on a rotating Earth?

If the earth is rotating (e.g. at 1000km per hour, at the equator), how can planes safely land on a moving runway?
4
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3answers
928 views

Why is the current atmosphere made of nitrogen (75.5%)?

As I read a book on meteorology, 4 billion years ago, atmosphere was made by steam, carbon dioxide, carbon dioxide and a few nitrogen. Then photosynthesis came, run by underwater organisms, which led ...