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1500 questions
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Esker vs. Kame vs. Drumlin - what's the difference?
In researching glacial features, I came across the terms esker, drumlin, and kame. I know that they are all depositional features that are shaped like a mound. My impression is that an esker is longer than a drumlin, which is longer than a kame.…
Cyclopropane
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Did climate cool down when underground hydrocarbons stocks formed?
As far as I understand, the dominant theory of modern climate change says that recent warming is mainly caused by the massive burning of hydrocarbons that used to be stored in solid form mostly underground as petroleum, coal, etc.
This suggests that…
Martin Van der Linden
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10
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1 answer
How much worse is the typical subway air, compared to street-level air pollution, in a typical city?
An excerpt from a section about the capital of Taiwan, in an article I wrote about Air pollution in Taiwan:
Further more, in greater Taipei, the outdoor PM2.5 concentration in
the air at ground-level up until the height of three-stories is…
O0123
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9
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How is geological time divided into units?
Earth's history is divided into eons, which are divided into eras, which are divided into periods etc. Consecutive time units differ in their geology and/or fossil species. But what events are the basis for dividing time into discrete bands?
Roughly…
J.G.
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What geological processes can cause local biases in the fossil record?
What are the main geological processes that can cause local biases in the fossil record, e.g. when comparing species diversity or species occurances in different areas from the same time period? I know that there exists several processes for…
fileunderwater
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9
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For how long has the Earth been habitable for humans?
Let's imagine that a human (male or female) could be sent to the
past, anytime after the birth of our planet. What would be their survival
probability over time?
If this question is too hard to answer, I would also be interested in the first time…
Martin Drozdik
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9
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1 answer
What is the geologic origin of Cryolite, and could there be more?
Cryolite is a mineral of aluminum (Na$_3$AlF$_6$). The only known natural deposit was found in Ivittuut, Greenland. It was mined from 1854 to 1987 and yielded 3.7 Mt of Cryolite ore.
Basically my question is, why is this the only cryolite deposit…
DrZ214
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9
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4 answers
Do divergent tectonic plates destroy mountains?
Tectonic plates meeting (convergent plates) form mountains. But if those plates change direction (which I am just assuming they can over time, I have no idea if it's true) and start pulling apart (divergent plates), will the mountains automatically…
Henry Stone
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9
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Is there a quick way to roughly estimate how quickly a flood will move downstream?
At the time of this post, there was urgent danger of spillway failure at the Oroville Dam in California, with evacuations in place for hundreds of thousands, and even larger populations further downstream in the Sacramento metro area. There's 300…
JeopardyTempest
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9
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2 answers
Why did it take so long to discover the volcanic nature of mid-oceanic ridges?
I just read this article and was astonished to see the following:
Oceanographers stumbled on [the mid-oceanic ridges'] volcanic nature in 1973.
What I find surprising is how recent that is.
Considering that
the history of geology in general goes…
pr1268
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9
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2 answers
How to compute du/dx and dv/dy in moisture flux convergence?
I have $u$-wind, $v$-wind and specific humidity. I would like to compute moisture flux convergence at a grid point. So I need to compute the value of $q(\frac{du}{dx} + \frac{dv}{dy})$
My question is how to compute $\frac{du}{dx}$ and…
Kay
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9
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1 answer
Dataset for expected sea level rise in case of massive meltdowns (Greenland/Antarctica)
Around the time climate change became a 'public issue' (let's say shortly after An inconvenient truth came out), figures started getting published about the expected (global) sea level rise in case of 'catastrophic' meltdowns of the large land ices…
Jan Doggen
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9
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4 answers
Temperature rise when snowing
Why does the temperature rise when it is snowing? Is it due to:
cloud cover
snow requires humid air and warmer air can carry more humidity (so in this case it would be the other way around, i.e. it snows because it is warmer)
something else?
user1583209
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In quasi-geostrophic frontogenesis, what happens if the potential vorticity is negative?
In particular, what happens if the Sawyer–Eliassen equation cannot be solved? I know that a condition for the Sawyer–Eliassen equation to have a solution is $F^2 N^2 - S^4 >0$, which means that the potential vorticity is positive.
I was wondering…
Alex
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What is the current equilibrium surface temperature of Earth, i.e. without the sun?
Without the sun to keep the Earth's temperature topped up to something comfortable, what would be the equilibrium surface temperature range. It would obviously be a balance between outgoing radiation and geothermal conduction to the surface. This…
Gordon Stanger
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