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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160 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 ...
5
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2answers
86 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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4answers
578 views

Can a small change in the Earth temperature give rise to large-scale climate changes?

Earth's atmosphere is a chaotic system. In such systems arbitrarily small changes the conditions can give rise to very large effects. There are many rumors about the physical and large scale ...
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1answer
100 views

What physical phenomena underly the shape of this graph of diurnal UV index?

When I dig up a graphs of UV index versus time-of-day, most graphs are characteristically shaped like one of the plots shown here: That graph is from this site. What physical phenomena underly ...
13
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1answer
191 views

What is the current physical theory of what causes the 'Morning Glory' roll cloud over Northern Australia?

The Morning Glory roll cloud (pictured below): from this Wikipedia page, which briefly describes the landform and meteorological causes, but states The Morning Glory cloud is not clearly ...
3
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1answer
120 views

Why does the airflow in the mid-stratosphere of the northern hemisphere rotate FASTER than the earth?

I have been playing around with this nice visualisation and noticed that in the mid-stratosphere (P=10hPa), the airflow around the equator and south of it is in the opposite direction to the earth's ...
8
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1answer
56 views

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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0answers
75 views

Mathematical approaches to atmospheric refraction

Understanding atmospheric refraction, particularly of ultraviolet, and into the blue part of the visible spectrum is of great interest to me. Although, I have a strong background in trigonometry and ...
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2answers
489 views

Why did they used to make the mill chimneys so tall?

Why did they used to make the mill chimneys so tall? This question was asked in an Engineering Interview at Cambridge University.
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1answer
33 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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2answers
90 views

Relative velocity decomposition

In my fluid dynamics course notes is stated a change in relative velocity can be decomposed: $$\delta \mathbf{v} = \left\{ \begin{pmatrix} \Delta & 0 \\ 0 & \Delta \end{pmatrix} + ...
5
votes
1answer
399 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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0answers
55 views

What are the physics challenges of rain farming [closed]

Rain farming is an engineering concept, employing the technology of industrial cooling towers, to deliver vast amounts of water to the lower levels of the troposphere as warm moist air. This question ...
20
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1answer
526 views

Causes of hexagonal shape of Saturn's jet stream

NASA has just shown a more detailed picture of the hexagonal vortex/storm on Saturn: http://www.ibtimes.com/nasa-releases-images-saturns-hexagon-mega-storm-may-have-been-swirling-centuries-1496218 ...
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2answers
107 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 ...
5
votes
1answer
107 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 ...
8
votes
1answer
140 views

'Hole in the clouds' in the Sarychev Peak eruption

One of my favourite ever pictures taken from space is a picture of the 2009 eruption of Sarychev Peak (Ostrov Matua island, Japan) taken by an ISS astronaut during a lucky fly-over. Image Source: ...
2
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0answers
131 views

How Temperature, Pressure and Altitude are related in the atmosphere?

I'm looking for an approximation for the temperature of the atmosphere at any height and pressure. Both altitude and pressure are known variables, I've derived this equation using maxwell's ...
2
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1answer
103 views

Whirlwind/tornado/dust devil in the middle of nowhere

I live in area which have many properties similar to desert. Many times when I drive by I see a whirlwind/tornado/dust devil of sand or other garbage parts. I would like to ask how this was normally ...
7
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4answers
3k views

Does the moon affect the Earth's climate?

So, this morning I was talking to a friend about astronomical observations, and he told me that lately there has only been good weather when there was a full moon in the sky, which was a shame. I ...
2
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0answers
31 views

What is the mean ionospheric height?

I am reading some articles about the ionosphere and I am a little bit confused about the terms mean ionospheric height and effective height of the ionosphere. Are these the same thing? I would ...
2
votes
2answers
177 views

Cloud Microphysics - Does It contain Ice Or Water Or Both?

I'm not sure if this is the right site to post this on but I have a project where I have some cloud microphysical properties: ...
8
votes
1answer
109 views

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 ...
2
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1answer
93 views

What confines atmosphere around earth?

Exactly the title. There needs to be a pressure to prevent gases from perpetually expanding, right? Bear with me, I'm not a physicist or studying to be one.
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2answers
1k views

Why England is 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?
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3answers
1k views

Calculating Atmospheric Pressure on an Imaginary Planet

I am planning a series of science fiction novels that take place on an imaginary binary planet system. Both planets have a lower surface gravity than the Earth and one has slightly more mass than the ...
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1answer
132 views

Why do planets other than earth have colours?

I know Mars has many red rocks and mountains. But since it does not have any atmosphere, it shouldn't have any color. So, why does it appear red?
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3answers
2k 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. ...
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5answers
2k views

Can Helium Disappear from Earth?

Can Helium disappear? As we know Helium is lighter than air, so basically Helium fly off from Earth. Is it possible that in the future we will run out Helium?
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vote
1answer
62 views

What is the height of breeze/wind?

How high does a breeze/wind blow? (If you are out in the open and can feel the breeze blowing, till how high is this breeze felt?) And what are the factors that affect it?
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votes
1answer
658 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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3answers
847 views

Are the air particles in today's wind on earth (more or less) the same as the air 2/3 billion years ago?

So the air pressure on earth remains relatively constant, right? Is there air gained or lost through transitions of any sort? e.g. plumes going out into space, earth gaining new air particles with ...
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2answers
401 views

Hot Air Balloons: how is the Lift related to environmental conditions?

I'd like to build a small hot air balloon big enough to carry 0.8kg (a camera). The first thing I need to know is: once I have a big enough plastic bag and a big enough source of fire, how much will ...
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2answers
150 views

Does gravity affect radiation incident on the planet?

Just curious ... Known facts: When outside the atmosphere levels of radiation are higher Typically such radiation is CBR, Solar Radiation Question: If the matter of the atmosphere and ...
2
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2answers
79 views

Can be the ionosphere described as an elecro-magnetic field?

I read that the ionosphere can be defined as plasma. it has its plasma frequency it has its Debye length it is overall neutral As it is overall neutral it does not produce any electric field. ...
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vote
1answer
115 views

What is the necessary amount of energy to propel a 100g from ground to orbit ? (Slingatron)

I would like to know what is the energy needed considering the air resistance to shoot from ground to the orbit a 100g object (even if it vaporizes in the process). Variables to make approx ...
7
votes
1answer
621 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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1answer
550 views

What's the altitude of the flat base of Cumulus clouds?

Is there a formula that describes the altitude of clouds with respect to the local temperature? I think of the flat bases of Cumulus clouds. Thanks...
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4answers
5k views

What is the difference between air pressure and atmospheric pressure?

I know that air pressure and temperature are inversely proportional. Now I saw in a book that "Atmospheric pressure decreases as we go higher and higher." But at greater heights the temperature ...
4
votes
1answer
129 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 ...
2
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3answers
396 views

Why does the wind direction vary locally?

If the air is flowing with the earth, as it rotates, how do we feel a breeze and strong winds at times, as everyone has experienced, the wind shifts as if from many directions.
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0answers
55 views

Why stars twinkle but planets don't? [duplicate]

I am not from a physics background. I came to know this while studying probability? Is this because the planets are nearer than the stars so we get average behaviour rather than random. Is law of ...
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0answers
138 views

seemingly impossible query

While on an expedition to a lake, it was noticed that the wind speeds gusted violently in seemingly periodic wakes and the proposed explanation was Von Karman vortex shedding off of nearby mountains ...
4
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1answer
310 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 ...
2
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2answers
5k views

In an ideal gas, if temperature increases, will pressure or volume increase?

This question came up when I was talking about the atmosphere. Someone had mistakenly claimed that as temperature increases, the density of the atmosphere should increase as well. I reasoned from the ...
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2answers
1k views

Why is getting a tan in the evening less likely than getting a tan in the morning?

When I was young I read one book in which is written that you get more tan on the morning than on evening even light angle from Sun to Earth is the same. Don't remember exact reason, I think because ...
14
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2answers
264 views

Why do clouds form in lumps?

What forces drive the water vapor to form the shapes every child draws? Why isn't water vapor forming an uniform mist layer consistently (which it some times does)? I have two general ideas how this ...
3
votes
2answers
111 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
98 views

Rate of twinkling of stars

According to "Why do stars flicker?", the twinkling of stars (stellar scintillation) is caused by the thick layers of turbulent air in the Earth's atmosphere. While the explanation is convincing, it ...
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1answer
5k 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 ...