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1500 questions
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Is it true that "All life on earth gets its energy from the sun"? How much biomass is not derived from photosynthesis?
In helping my son with his college biology I ran across some statements that I think are wrong according to updated data. The copyright is 2017 so it is supposed to reflect the most current knowledge.
It makes the following assertion
"All life on…
0tyranny0poverty
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Is there a special name for along-course elevation profiles of rivers, and where you can you find them?
Was discussing the terrain and rivers of Europe today with my father and it became apparent that a graph of the elevation versus course of a river would offer interesting insight, including a quick summary into the elevation of various cities of…
JeopardyTempest
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How much heat flow is needed to maintain plate tectonics?
The Earth is emitting about 47 terawatts of heat energy, producing a heat flow of 0.0921 W/m$^2$ due to radiogenic and primordial heat energy. The heat flow drives mantle convection which in turn drives plate movement. The radiogenic energy declines…
Anders Sandberg
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Changes in Earth's orbital and rotation speeds
What are the Earth's maximum and minimum orbital speeds around the Sun?
Is there any way to calculate orbital speed at any point of Earth's orbit? Is there a way to relate this to the calendar?
Does the change in speed during an orbit around the Sun…
PSA
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Volcanoes in the Alps and Himalayas and the subduction of Tethys Sea
Geologist have theorized that the Tethys Sea subducted under Eurasian plates. But where are the volcanoes that would have resulted due to this? Where are the volcanoes in the Alps and the Himalayas?
Porcupine
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Where did the daily temperature variation go?
Currently central and northern Europe are experiencing a very cold, false-spring like weather phenomenon.
When i look at local weather charts, the daily temperature cycle seems to be completely gone, and replaced by a constant -8°C to -10°C, see…
AtmosphericPrisonEscape
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Correct phrase for a 'forgetful' natural system?
This is a rather general question: assume I have a system that has a certain 'forgetful' property, which means that while I can offset its current state for a moment, it will eventually return to its undisturbed state. An example would be a length…
C.Miller
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Is the iron on Earth's crust a leftover of the Iron catastrophe, or it was brought back by volcanoes?
When pondering the hypothesis of the Iron catastrophe, that seem to be widely accepted nowadays. It surprises me that currently the crust still contain a significant amount of Iron (5.6% in weight).
I wonder if that much Iron is what didn't sink in…
Camilo Rada
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Is the Arctic ice dissapearing faster than IPCC models say?
Are observations of Arctic sea ice in accord with what the IPCC forecasts says they should be? And as such is the ice reducing in an exponential or linear way?
For instance, from…
Jimmy Widdle
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Why is carbon pollution given more importance than Sulfur pollution or Nitrogen pollution?
Nitrous oxide ($N_2O$) - primary greenhouse gas
Carbon dioxide ($CO_2$) - primary greenhouse gas
Methane ($CH_4$) - primary greenhouse gas, explosive
Nitrogen monoxide ($NO$) - secondary greenhouse gas, toxic
Nitrogen dioxide ($NO_2$) - secondary…
Neel
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What is the consensus among geologists about climate change being caused by humans?
I'm terribly frustrated with the way that climate change has been debated in Europe. I live in the Netherlands and members of one of the biggest parties here, the Party for Freedom (PVV), frequently deny climate change and use terms like "climate…
titusAdam
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What conditions could produce 50 km long lava tubes?
Detection of a new 50 km long lava tube in the Moon has just been reported. See JAXA probe finds 50-km cavern under surface of the moon, this JAXA news page (the English page has not yet been updated, stay tuned) and Detection of intact lava tubes…
uhoh
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Will global warming lead to agriculture in the Arctic?
From what I understand, global warming will make growing food a lot harder in areas like the American Midwest because temperatures will become too high for most crops. At the same time, Arctic (and Antarctic) regions will heat up and permafrost will…
sbl
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Can we predict which annular modes existed during the time of Pangaea?
Some examples of annular modes include ENSO, NAM, and SAM.
I think one of the major mysteries of them is how they formed to begin with.
I'm just curious - do we have any idea of whether or not these annular modes existed in paleoclimates,…
InquilineKea
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Is every space group realized by some mineral?
Every mineral has it's own internal building scheme, a lattice on which it's atoms lie. Mathematically, this can be described by the space group of the mineral. From mathematical considerations it's known that there are exactly 230 symmetry groups…
agb
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