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1500 questions
13
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1 answer
How significant is a 5-10 mb drop in pressure over a 20 minute period?
I would be interested in seeing how significant a 5-10 mb drop in pressure would be at the surface, and 80 m in the air. The temporal scale would be 20 minutes. If the pressure starts to steadily increase after the drop in pressure, would this hint…
climatefreak
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Epicenter location of the 900-930 A.D.,7.4 Magnitude Seattle Earthquake?
I am preparing a seismic hazard map of Seattle and I was curious about the great 7.4 magnitude earthquake that occurred in the Seattle area during 900-930 A.D. On a second note, is it possible to infer the epicenters of paleoearthquakes (earthquakes…
Guru Rahul Pradhan
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13
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7 answers
Why don't errors accumulate in climate models when the time horizon increases?
First of all, I want to add the disclaimer that I am not a climate sceptic or anything. I honestly want to understand this phenomenon. Hopefully, someone can also go into the details as I do have somewhat of a statistical background.
According to…
strateeg32
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13
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3 answers
Why are there no volcanoes where continents collide with each other?
I understand that volcanoes occur where oceanic crust is subducted under continental crust such as the Andes. However, they don't occur at places like the Himalayas and Alps where continental crust is colliding with another chuck of continental…
John McCarthy
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13
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How does the sand appear on Hawaiian beaches
It's quite surprising to me that there's only one beach with black sand on Hawaii (maybe not exactly one beach, but it's only a very small fraction). The concern is, if the whole Hawaii is volcanic, therefore made of frozen lava, the sand should be…
yo'
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How does soil redox potential affect the rate of denitrification?
Denitrification requires low oxygen conditions as wells as organic carbon.
Are reduced soils (e.g gleysols) more likely to have higher denitrification rates because they have low oxygen levels?
nolisgol
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13
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3 answers
If the Bennu asteroid were to hit within a 500 mile radius of Yellowstone National Park, will it trigger a super volcano at Yellowstone?
I am curious to know if it would be highly probable that if the Bennu asteroid were to hit the Earth in 2182, and the point of impact is within a 500 mile radius of Yellowstone National Park, will it most likely trigger a super volcano at…
user57467
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13
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1 answer
Formation of limestone without living organisms?
Limestones are formed mostly from skeletal fragments of marine organisms.
However, calcium carbonate dissolves naturally in water, so the living organisms are not the only source of it in water.
Is it possible for limestone to form without living…
Danubian Sailor
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2 answers
Determining the paleoelevation of mountain ranges
In New Delhi, a lot of people say that the
Aravali range used to be as tall as the Himalayas. How do scientists know that some mountain range used to be a lot taller millions of years ago, and what is the process by which mountains erode in…
theVerma
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13
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5 answers
How will increased $\ce{CO2}$ affect forests and other vegetative areas?
Some researchers contend that increases in atmospheric CO2 (e.g., from anthropogenic emissions) will enhance plant growth in general.
What is the level of that enhancement?
Does the associated climate change simply make it easier for invasive…
f.thorpe
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13
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2 answers
Why is the deep sea cold?
Except near thermal vents, the deep ocean is generally considered to be quite cool. For instance, water temps in the Mariana Trench (~10 km deep) are 1-4 °C.
However, the geothermal gradient runs counter to that, where the lithosphere at the same…
Kenn Sebesta
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13
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1 answer
What is an "exquisitely rare pollen corona"? How can pollen produce several tight rainbow circles around the Sun, and why pollen specifically?
The Forrest Mims YouTube video An Exquisitely Rare Pollen Corona shows a pair of rings closely circled around the Sun with rainbow colors; blue on the inside.
The first annulus is easy to see, the second is faint so I've played with the color and…
uhoh
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13
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3 answers
What are the differences between implicit and explicit methods when applied to modelling Earth systems?
I am struggling to understand the difference between implicit methods and explicit methods in numerical modelling of Earth processes, particularly when applied to modelling Earth systems in 2 or more dimensions, such as in NWP (Numerical Weather…
decvalts
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13
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1 answer
Great Lakes - cookie cutter clouds
On 2014-07-10, in the afternoon, the GOES East satellite image in the visible showed a mass of cloud in central North America. However, in the middle, the Great Lakes stood out in a most extraordinary way, since they were almost completely free of…
John
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3 answers
How to determine how long ago a rock was broken?
I know that there are techniques that help scientists determine the age of a rock. But is it also possible to determine how long ago a rock was broken? For example, how could we date the formation of the fracture surface in the photograph below?
B Faley
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