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1500 questions
13
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How did CO₂ originate on Earth before there was life?
To start life there has to be $\ce{CO2}$.
$\ce{Solar energy + 6CO2 + 6H2O -> C6H12O6 (sugars) + 6O2}$
$C_6H_{12}O_{6} + O_2 \longrightarrow H_2O + {CO}_2 + \text{Energy}$
So to start this cycle, life needs $\text{CO}_2$.
Where did the $\text{CO}_2$…
Marcel Plan B
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13
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Why does Earth have two kinds of crusts?
Why does Earth have two clearly differentiated kinds of crusts, namely continental and oceanic? How did they differentiate initially and why don't they get mixed up over time?
Stephane Bersier
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13
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What is the loudest thunder ever recorded (dB) at ground level and where did it occur?
Sound travels fastest through warm air and conditions such as temperature inversions can help to amplify the sound of thunder (source). Conversely, during a thundersnow event the falling, and accumulated, snow can act as an acoustic suppressor…
user11318
13
votes
2 answers
Did the formation of Panama trigger the beginning of Ice Ages?
I have been studying ocean currents and associated energy flows in the eastern Pacific and western Atlantic oceans. I also looked at El Nino cycles.
I also noted when the large glacial periods started 3 million years ago and noticed that these…
0tyranny0poverty
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13
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How are giant sinkholes filled up?
There are a few impressive photographs of giant sinkholes that appeared in cities, such as this one:
However, followup information (e.g. Guatemalan sinkhole) or photographs on how these kind of sinkholes are filled up is hard to find. What…
Armfoot
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13
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3 answers
What are the distinguishing features of an "artificial seismic wave" (e.g. a large underground explosion)
IN the NPR news item North Korea Possibly Conducts Sixth Nuclear Test, South Korea Says:
The U.S. Geological Survey says it detected a 6.3 magnitude "possible explosion" near Sungjibaegam, North Korea Sunday afternoon, "located near the site where…
uhoh
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13
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2 answers
Which are the biggest methodological differences between the archaeological and geological approaches to stratigraphy?
Stratigraphy, or study of rock or soil layers (strata), was originally introduced as a branch of geology. However, it is often applied in other disciplines, especially in archaeology and paleonthology. As an archaeologist (though not a field…
Pavel V.
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13
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1 answer
Carbon Dioxide levels appear to be linked to the Milankovitch cycles according to Ice Core data but what is the mechanism?
As in ice core data shows that $CO_2 $ levels have fluctuated on levels correlating to the temperature and ice levels, but I couldn't think of a mechanism for what might be the link between the release of carbon dioxide and other gases, and…
AlexLipp
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13
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2 answers
What are the guidelines for constructing variable names that follow CF conventions?
I am attempting to develop variable names following Unidata's climate forecasting (CF) variable naming guidelines, but for biological variables used to parameterize and evaluate land surface and ecosystem models (See a first draft on Google drive).…
David LeBauer
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13
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1 answer
Why does halite have perfect cleavage at the (110) plane?
Why doesn't it cleave nicely along the (100) or (010) or any other planes? What determines its cleavage plane? I know it has something to do with the fact that it crystallizes in face centered cubic system but I don't understand why things happen…
Tamás
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0 answers
How are scatterometer observations standardised before being fed into reanalysis models?
This very basic question occurred to me during a talk on reanalysis data sets. Often we know the observations produced by a particular instrument, say rain radar, are biased from one year to the next because of changes in how the instrument has been…
Ewan
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13
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2 answers
What are those arrowlike underwater structures for?
Looks like it has something to do with fishing: Google maps link
ZuOverture
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13
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What causes the beautiful Auroras on the north and south magnetic poles?
What is the scientific reason for the majestic sights of the northern and southern lights, otherwise known as Auroras near the magnetic poles, and why do the northern lights differ from the southern lights?
Kenshin
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13
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Is Mars' mantle homogeneous or heterogeneous and what might this say about mantle convection?
A supervisor of mine made an off-hand comment about the fact that Mars used to have plate tectonics, and there is evidence that Mars used to have plate tectonics, however now it does not. The theory that she mentioned was that Mars is either…
AlexLipp
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13
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1 answer
Is there a standard definition of the term "mountain"?
Is there any standard internationally recognizable definition of the term "mountain"?
If international texts describe some terrain as mountains, do they use some international definition of the term, or do they use the local definitions?
For…
Danubian Sailor
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