# Tagged Questions

Meteorology is the interdisciplinary scientific study of the atmosphere.

17 views

### Precise timing for a meteor impact [on hold]

Do we have the tech to change a meteors path to use the moon as a shield? We may not be able to steer it away but slow or speed it up to hit the moon instead of the Earth?
42 views

### Wind Flow Simuation Equation

I have a data that contains pressure measurements in difference locations. Now i want to do wind flow simulation based on the pressure difference between these places. The problem is i want to do this ...
44 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 ...
45 views

### What is the explanation of the glory (optical phenomenon)?

Yesterday, I took the following picture. I was looking downwards from within an aircraft and I saw the 'glory' around the shadow of the plane on the clouds below. Wikipedia has an entry on the ...
23 views

### How could I calculate the Heat Index with low humidity?

The formula shown in the Heat Index(HI) requires that the relative humidity should be equal to or greater than 40%, so how to calculate the heat index when the humidity is less than 40%? Or is there ...
29 views

### Dispersion parameters for Pasquill–Gifford stability class G (extremely stable)

Gaussian plume models are often used to model atmospheric dispersion because they are simple and computationally efficient. When not constrained by the ground or by inversion layers, the Gaussian ...
30 views

Adiabatic lapse rate is defined as $$\Gamma_a \equiv -\left(\frac{dT}{dz}\right)_{\rm parcel}=-\frac{R_{\rm a} T}{c_p \,p}\left(\frac{dp}{dz}\right)_{\rm parcel} = \frac{g}{c_p}$$ $R_a$ is gas ...
80 views

### How to estimate wind speed from a pressure difference?

Does a formula (or a rule of thumb) exist to estimate the wind speed between a high pressure area and a low pressure area given the pressure difference between the two areas? Only the wind resulting ...
21 views

### How are homogeneity or heterogeneity of materials decided?

How is the homogeneity or heterogeneity of materials decided? What kind of measurement or assessment exists for inferring when e.g. the density of the material of an object is uniform across the ...
60 views

### Why is it always foggy on new years eve?

I live in Hamburg in northern Germany and a few years ago I started to notice this: It is always foggy on new years eve. Yesterday there even was a sight distance of about 10 meters at some point. ...
121 views

### Hyperbolic flow / vector field - irrotational and divergence-free?

My text book on meteorology claims that a hyperbolic flow pattern is both divergence-free and irrotational: (d) Hyperbolic flow that exhibits both diffluence and stretching, but is ...
87 views

### Why lightning most likely occure in night?

This is a question based on my experience. I am not going to prove that lightning (succeed by thunder) never occure in day, but it seems it most likely occure in night. May the humidity of air become ...
64 views

### How do you see a rainbow?

I know that we observe rainbows from light being reflected off of water in the atmosphere. So, what angle of incidence must exist between an observer and the sun in order to see the colors of the ...
81 views

### Here's a fun question, what would happen if Venus was thrown off in a highly elliptical orbit? [closed]

I'd like to know what would happen if Venus was flung into a highly eccentric orbit like Sedna (except maybe with its current perihelion) with an orbital period measured in thousands of years by a ...
60 views

### Is there a theoretical maximum speed for wind?

What we call wind is actually molecules moving into an area of lower particle density due to their thermal motion. A lower particle density offers less collisions (resistance), so more molecules move ...
27 views

### calculating air humidity from air temperature and specific humidity

Is it possible to calculate air humidity in mb from measurements of specific humidity (kg/kg) and air temperature (degC)? I'm trying to run a model (http://www.flake.igb-berlin.de/sourcecodes.shtml#...
38 views

### Weather Meridians

Are there meridians that effect cloud movement? While observing radar images of moisture bearing cloud movements (at my location in Florida), I've noticed a splitting of the cloud formations a ...
120 views

### Why do nuclear bomb explosions create an array of visible electric discharges in the form of lightening in the upper atmosphere?

I've seen videos on the internet, showing nuclear bomb test explosions, and there appears to be a large amount of visible lightening discharging numerous times over the development of the mushroom ...
47 views

### How much does barometric pressure change over minutes?

I have to correct an ongoing experiment for atmospheric pressure. This means that during the experiment I must read a chip that measures barometric pressure. The question becomes one of how rapidly I ...
146 views

### How much atmospheric pressure (CO2) is required to carry iron oxide dust in the wind?

It is common knowledge that there are dust devils and dust storms on Mars. But can we demonstrate that the atmospheric pressure on Mars, which is 0.6% of the pressure we experience on Earth, provides ...
58 views

### Difference between mixing ratio and mole fraction

I have been reading 'The Atmosphere of Venus' by V.I. Moroz which is available here. I am confused about the term 'mixing ratio' which is used on discussions in chemical composition. From what I ...
252 views

### Will the upcoming solar eclipse stress the European electrical grid?

From an article in the Financial Times today, about a solar eclipse on March 20th, 2015: An eclipse of the sun next month could disrupt Europe’s power supplies because so many countries now use ...
84 views

### On quantum randomness, the longest weather predictions and perfect macroscopic caos

Which is the maximum number of days we can predict future weather conditions with a reasonable degree of accuracy if we knew all of the initial conditions of everything that effects the weather down ...
24 views

### Hildring - Influence of vertical temperature gradient on light beam curvature

In special atmospheric condition it is possible to see coastline that normally is behind the horizon. It is apparently lifted to become visible. In Scandinavian the phenomenon is called 'hildring', a ...
116 views

### What does “downshear” mean?

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

### How would we explain meteorological phenomena in an inertial reference frame?

The Coriolis effect is used to explain the formation of typhoons, hurricanes, and cyclones and other phenomena where we take the Earth as a rotating reference frame. How could we explain this ...
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 ...
33 views

### What does “shortwave radiation” mean to a meteorologist?

I'm have an empirical model developed using surface observations of radiation (400-1100nm). I tend to think of this as visible, near infrared, and a little bit of shortwave infrared. I now need to ...
15k views

### Why is the sky never green? It can be blue or orange, and green is in between!

I, like everybody I suppose, have read the explanations why the colour of the sky is blue: ... the two most common types of matter present in the atmosphere are gaseous nitrogen and oxygen. ...
8k views

### Lux and W/m2 relationship?

I am reading a bit about solar energy, and for my own curiosity, I would really like to know the insolation on my balcony. That could tell me how much a solar panel could produce. Now, I don't have ...
60 views

I used to live in Italy, and when it was sunny, well, as expected it was pretty hot. Both under the direct light of the sun through the atmosphere, and in the shade, where the temperature was of ...
1k views

### Can rain evaporate?

Are there any atmospheric condition under which a visible raindrop can fail to hit the ground by evaporating first? I imagine this would require a large vertical temperature difference, and possibly ...
55 views

There are spectacular rotating towers of fire that can be seen in recent television images of fire in California. In this video, we see that these fire towers can rotate either clockwise or counter ...
229 views

### First law of thermodynamics applied to atmospheric fluid

I was reading an article that talks on a climate prediction model. This article proposes the following equation (energy balance): \rho_0 c_v\left( \frac{\partial T}{\partial t} + \sum^{3}_{j=1} ...
36 views

### How does atmospheric pressure work? [duplicate]

I heard that yesterday the atmospheric pressure at my location was exceptionally higher than normal and that explained why I had such a terrible headache all day. But what remained unclear was... How ...
8k views

### Without seeing the lightning, can you tell how far away it struck by how the thunder sounds?

Is there any way to tell how far away a lightning strike is by how its thunder sounds? I thought one way might be by using the fact that higher frequencies travel faster than lower frequencies. Would ...
349 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 ...
747 views

### Does an object's movement affect the likelihood of being struck by lightning?

Does the state of whether an object if moving or stationary affect the likelihood of it being struck by lightning? I suppose some things that could be considered would be: Whether the movement ...
235 views

### Why can't we see clouds everywhere around us?

We see clouds at a particular height,and not everywhere near the ground.I am not really well versed in the concept of cloud,but I felt the clouds would be lighter by the way they look.So,they should ...
8k 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?
154 views

### How is the energy of a lightning calculated?

I was wondering how is the energy of a lightning measured? Is it based on the luminous intensity and/or the generated sound? What about the generated heat and energy spent in the production of ozone? ...
390 views

### Weather difference on Mars compared to Earth

How the weather on Mars differs from here on Earth? In here you see that weather on Earth is Hurricanes, typhoons and tornadoes a real problem. Disgustingly interminable fog in coastal California....
1k 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...
417 views

### Why was the conversion factor of the metric unit bar chosen the way it was?

The unit bar for pressure is clearly a metric unit, but its order of magnitude is a bit strange. In the centimeter–gram–second system of units we have: ...
692 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.
97 views

### why does air temperature change with density?

As hot air in the atmosphere rises it expands and cools at the same time. If the air cools though, shouldn't its density increase?
175 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 ...
356 views

### How to derive a physical model of temperature above the earth surface?

At a point on the surface of the Earth, if I go straight "up" a distance $z$ (radially outward from the Earth), I'd observe a temperature profile $T(z)$. The conventional wisdom from the meteorology ...