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Questions tagged [geophysics]

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.

The study of the physical processes and properties of the planet Earth. Its subject matter includes

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Explain it to me like I'm a physics grad: Greenhouse Effect

What is the mechanism by which increasing $\rm CO_2$ (or other greenhouse gases) ends up increasing the temperature at (near) the surface of the Earth? Mostly what I'm looking for is a big-picture explanation of how increasing $\rm CO_2$ affects the…
Dave
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Why is there a scarcity of lithium?

One of the major impediments to the widespread adoption of electric cars is a shortage of lithium for the batteries. I read an article a while back that says that there is simply not enough lithium available on the entire planet to make enough…
Mason Wheeler
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Why don't miners get boiled to death at $4$ km deep?

The Mponeng Gold Mine is nearly $4$ km deep. It has the largest elevators in the world and is considered one of the most dangerous mines in the world. The geothermal gradient is $25$ degrees Celsius per kilometer, which would be $100$ degrees.…
Ambrose Swasey
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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?
user56903
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Why don't the Earth's oceans generate a magnetic field?

Many questions have been asked here about why the Earth has a magnetic field, e.g., What is the source of Earth's magnetic field? How does Earth's interior dynamo work? How can an electrically neutral planetary core be geodynamo? Why does the…
Thorondor
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Why is it cold on the sea floor if pressure heats things?

I was reading this and it says that Microsoft put a server farm at the bottom of the ocean because it's cooler there. Particularly it seems to imply that it get's colder as you go deeper, "Since ocean water gets pretty cold toward the sea floor..."…
user273872
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Why is dry soil hydrophobic? Bad gardener paradox

When I forget to water my plants, and their soil becomes very dry, during the next watering I can see that the soil becomes hydrophobic. I can even see pockets of air between the repelled blob of water and the soil. On the contrary, when the soil is…
user46147
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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?
Martin
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Why does CNN's ‘gravity hole’ in the Indian Ocean dip the sea level instead of raising it?

Ref. There is a ‘gravity hole’ in the Indian Ocean, and scientists now think they know why According to CNN, the 'gravity hole' is an area of decreased gravity, compared with the surroundings. This article says that the lower gravity causes to sea…
Paul Uszak
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How does the Earth's center produce heat?

In my understanding, the center of the Earth is hot because of the weight of the its own matter being crushed in on itself because of gravity. We can use water to collect this heat from the Earth and produce electricity with turbines. However, I'd…
rydwolf
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Are there tides in the atmosphere?

Analogous to the tides of Earths oceans, do the Moon and Sun cause our atmosphere to bulge in what could be described as a low and high tide?
Alex
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Why do some location on Earth have only one tidal maximum per day instead of two?

Most places in the ocean have two high tides and two low tides per "day" (~25 hours). But I remember reading that some locations only have one of each per day. This answer has some great explanations as well as helpful graphics and links. I'll…
uhoh
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Does the sea level increase if an iceberg melts?

It was claimed that if an iceberg melts in the ocean, the sea level won't change as the ice displaces as much water as there will be melted water. The other claim was that the sea level should rise because oceans contain salt, so the water in oceans…
Jaakko Seppälä
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Why can't the Earth's core melt the whole planet?

Earth core temperature is range between 4,400° Celsius (7,952° Fahrenheit) to about 6,000° Celsius (10,800° Fahrenheit). Source Why can't the Earth's core melt the whole planet? In other words, what is stopping Earth from being melted up to its…
Dean Moxley
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What is the net charge of the Earth?

This question arose in a seminar today about the solar wind... This is my vagueish understanding of the problem - please correct if you see errors! The 'classical' picture of atmospheric electricity is that the Earth as a whole is neutral, but that…
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