The study of the physical processes and properties of the planet Earth. Applicable to many subjects about Earth, such as its shape, its magnetic field, and ocean currents.

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Why does Earth behave like Natural Bar Magnet?

What is the reason for the Earth to behave like a bar magnet and have poles (North and South poles)?
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393 views

Upper limit on the earthquake magnitude

From the Gutenberg-Richter law we know that the frequency of an earthquake is a power law, so virtually any magnitude is possible on earthquake event. But the earth has a finite size so there must be ...
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3answers
2k views

Is there evidence to support that the Earth has a molten core?

I am told the Earth has an molten core. Is this a theory or has this been proven?
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1answer
55 views

How much heating Earth inner core provide to the surface?

Compare to the energy that the Earth surface receives from the sun, how much power comes from the inner melted core ? How important is this contribution to the surface temperature ?
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375 views

Earth's core electric charge

Forgive my limited knowledge, but the Earth's magnetic field is created by the conductive liquid in the core and to the best I can tell organizing itself (which means separating charges?). Would this ...
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22 views

Betatron vs Fermi acceleration

According to the reference below, the plasma in a planetary radiation belt increases its temperature anisotropy through radial diffusion; temperature perpendicular to the background magnetic field ...
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2answers
84 views

Will the day/night cycle change when the poles melt?

I want to know what will happen to day and night if poles melt i think it will change but I don't know why? ^_^
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At what energy consumption would we get a 1 degree rise in the Earth's temperature?

If energy consumption continues to rise at (say) 4% per year, how long before the heat dissipation seriously impacts climate?
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34 views

Can surface waves exist near a fixed surface

(I'll phrase this question in terms of waves in an elastic medium, but this is a more general question.) Surface waves are waves near the surface of a medium whose amplitude decreases as you go away ...
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1answer
67 views

What is the longitudinal difference between the sub­solar point and the magnetic poles at time $t$ (hours)?

I'm trying to convert geomagnetic coordinate to geographic, but there are some steps in the paper which I'm reading, that I don't understand. I have the geomagnetic latitude centered around the ...
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If the gravity at the center of the Earth is zero, why are heavy elements like iron there?

If gravity is zero at the center of the earth, why is there a core of heavy elements, such as iron? Alternate question for the opposite hypothesis: If gravity is greatest at the center of the ...
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1answer
76 views

What happens if the Russians decide to nuke the Kola borehole?

I recently came across research on the Kola Superdeep Borehole in Russia. It's one of the world's deepest at 12 km (7.5 mi) down. If someone decided to hoist a nuclear weapon all the way down and set ...
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1answer
2k views

What if the earth's core goes cold?

What effects would occur if the earth's core goes cold? Would the planet stay liveable after this happens?
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5answers
1k views

Is the earth expanding?

I recently saw this video on youtube: http://www.youtube.com/watch?v=oJfBSc6e7QQ and I don't know what to make of it. It seems as if the theory has enough evidence to be correct but where would all ...
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4answers
4k views

Why has Earth's core not become solid?

The Earth is billions of years old, yet its core has not yet cooled down and become solid. Will this happen in the foreseeable future?
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4answers
598 views

How is wind created?

I know that 'blowing air is called wind', but what I don't know is, how is wind created? And I don't want the answer from Google Search. I want to know more about wind at the atomic or molecular ...
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1answer
295 views

What is the temperature of the clear night sky from the surface of Earth?

Before you all jump in with 2.73 K or thereabouts, this is more of an experimental question. It will obviously depend on humidity and radiation being scattered back towards the surface of the Earth. ...
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2answers
312 views

Where did the energy released due to gravitational binding energy of the Earth go?

The gravitational binding energy of the Earth is $2×10^{32} J $, so the same amount of energy must have been released during the Earth's history. According to this and this, the current internal ...
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522 views

Why do clouds appear black?

I have noticed clouds appearing black during rain. But I don't know what makes clouds to acquire that colour. This phenomenon doesn't appear every rainfall. There has to be distinction to white ...
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4answers
2k views

Why does the sky change color?

Why the sky is blue during the day, red during sunrise/set and black during the night?
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2answers
42 views

Calculating altitude without refering to atmospheric pressure?

Is the only way of calculating altitude to try to guess using the atmospheric pressure? Couldn't an electronic device analyze the force of gravity and conclude from that at what altitude it is ...
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2answers
7k views

In the earth's crust, why is there far more uranium than gold?

In parts per million in the Earth's crust Uranium is around 1.8ppm and Gold 0.003ppm. Given that it takes far more energy to create Uranium than Gold, why is this?
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139 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 ...
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1answer
85 views

How do wind turbines cause lightning?

I saw this paper about Lightning discharges produced by wind turbines More lightning strikes wind turbines than comparable non-moving structures. What would be the physical cause of this? Does it ...
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4answers
5k views

Why is Earth's climate so stable?

Earth wasn't always the only water-world in the solar system. Mars also appear to have started out wet but, as conditions changed, Mars lost its oceans. So, how has Earth managed to avoid a ...
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2answers
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Estimating the force needed to increase height of a mountain?

How would you estimate the force required by a tectonic plate to make the height of a mountain increase when it pushes against another? I've used a method to try and do it for Mt Everest and have ...
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1answer
339 views

Would days be longer as the polar ice caps melt? [duplicate]

I got question in my mind striking for several days but not able to prove it, suppose polar ice on earth melt, would the days be longer? My friend said it was due to moment of inertia of the earth ...
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1answer
639 views

live Kp index data

I need to create an online service displaying latest Kp index. Where I can take the data? The data should be in machine-readable format, i.e. text files, XML, or CGI gateways, for instance. No ...
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0answers
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Richter scale equation

According to Wikipedia, the equation for finding magnitude according to the Richter scale is $M_\mathrm{L} = \log_{10} A - \log_{10} A_0(\delta)$. However, it is rather ambiguous as to the effect of ...
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1answer
56 views

Geophysical Effects of Supernova Neutrino Pulse

While neutrinos are generally totally harmless, a supernova produces enough of them at once that the neutrino flux would kill you if you could stand close enough (and not be killed by other means ...
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2answers
208 views

Earth's Temperature

I have a question regarding earth's temperature... How come the average temperature in the middle east (Israel, Saudi Arabia, Sudan or lower) is always so much significantly higher than in Europe ...
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1answer
249 views

Amplitude decrease during geometrical spreading of a seismic pulse

I'm looking at amplitude decrease of a seismic pulse as a result of geometrical spreading. Starting with the energy contained in a unit area, $I = E / (4 \pi r^2)$, where $E$ is the original energy ...
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1answer
120 views

Why does absorption cause seismic pulses to increase in length over distance?

The specific question I'm trying to answer is "How does the progressive loss of higher frequencies in a propagating seismic pulse lead to an increase in pulse length?" I understand how the higher ...
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124 views

Does the geomagnetic field rotate?

The Earth rotates about it's own axis. Do the geomagnetic field lines rotate due to this rotation or not?
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4answers
493 views

How does water carve rock?

How does water carve rock? And more generally, how does a soft material carve a hard material? Obviously it happens, but is it a continual process (every drop of soft water carries away a minute ...
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39 views

Geophysics with earth science [closed]

I am a communications engineering student. I am interested in doing a project on geophysics. The concept is for a hole-digging robot with a camera and sensors and wireless transmitter that is made of ...
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5answers
1k views

Why the water remains on the surface of the Earth?

What makes the water stay on the surface? Why the earth does not absorb the water in it?
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54 views

Sun radiation in England

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 ...
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2answers
154 views

Does the Earth's core have tides?

Does the moon produce a measurable tidal-effect on the Earth's (liquid) core? If so, how strong is it? Would it play a factor in other geological effects like earthquakes, volcanoes, etc?
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1answer
171 views

Could we obtain free electrical energy from the Earth's magnetic field? [duplicate]

If there exists a natural magnetic field due to the metallic core of the earth... could we then extract and get free energy from the earth core ??
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1answer
129 views

Tidal Forces from the Moon on the Earth's Crust

How do we determine how much the surface of the Earth deflects due to tidal forces from the Moon (and Sun)?
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Does the conversion of crude oil to greenhouse gases have any measurable effect on earth's gravitational pull?

Oil underground is much denser than greenhouse gas in the atmosphere. Does the conversion in anyway effect the gravitational force from earth.
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3answers
9k views

Is the Earth negatively or positively charged?

The Earth carries a negative electric charge of roughly 500 thousand Coulombs. Does that mean the Earth is negatively charged?
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385 views

Radio-dating and the age of the earth

I understand there are a few radio-dating methods to determine the age of the earth, uranium-lead to name one (maybe not the best though). The ratio Pb206 + Pb207 to U allows you to find when the ...
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1answer
56 views

Effect of CO2 on the environment, besides greenhouse effect and ocean acidification [closed]

What effects does the raising level of CO2 in the atmosphere have, besides being a greenhouse gas and responsible for the increased acidity of the oceans? What other environmental damages does it ...
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3answers
486 views

Calculating the mass of a wave of water

I am assuming it is possible to calculate the mass of water if the volume is known. My assumption is that doing this for stagnant water, in a container perhaps, is easy. However I want calculate, ...
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0answers
52 views

Earth as a conductor and emf produced? [closed]

Since about 73% of total surface of Earth is occupied by water, its internal is also occupied largely by hot molten mass.Let,the whole earth is considered a conductor.Sun is a source of gravitational ...
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6answers
729 views

Tsunami dampening mechanisms

Encouraged by the zeitgeist let me ask the following: Is it feasible (now or in the future) to build systems a certain distance of a vulnerable coastline which can serve to dampen a tsunami before it ...
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4answers
2k views

How do we know that earth is not perfect sphere?

I've just read here that: Equatorial radius = 6378.16 kilometers. Polar radius = 6356.78 kilometers, so the difference in circumference is 71.1 kilometers. It is not a perfect sphere, but kind ...
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225 views

Why is the geomagnetic north pole at a different location from the magnetic north pole?

According to this site Magnetic North, Geomagnetic and Magnetic Poles The Geomagnetic poles (dipole poles) are the intersections of the Earth's surface and the axis of a bar magnet hypothetically ...