# All Questions

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8 views

### How many supercontinents have there been?

With plate tectonics, supercontinents split up into smaller continents, and then the smaller continents get mashed up together to form a new supercontinent. There used to be a single supercontinent ...
12 views

### Discharge waste water - content allowed, most strict, universal rule set

Where can I find non-country specific, general or most strict set of rules that would pass in most countries, about allowed content of waste water that is allowed to be released into the environment, ...
25 views

### Is there a physical limit to the heights of mountains? [duplicate]

I am reading a fantasy novel where there is a mountain range where the average mountain height is 10 miles, so some higher some lower, but all extremely high. This got me wondering if such a mountain ...
32 views

### How to properly distinguish a transversal valley from a longitudinal valley?

I'm confused about how to distinguish the two. Prior to making this question. I've read the wikipedia entry on the subject but it mentions that for example a transverse valley makes 90 degrees with ...
60 views

### map projections that minimises differences

I have an odd map projection requirement, but I would like a world map projection where even very small countries, like Luxembourg or Belgium are still visible when also showing China and Canada on ...
23 views

### How to specify a certain place in a (CDS) weather data query?

I am trying to get time series data for a specific place (latitude and longitude) for different weather elements from the CDS datapool. Therefore, I am using the cdsapi package and can run queries ...
81 views

### How to get the exact temperature from 1880 to 2020? [closed]

Wherever I look, I find "Temperature Anamolies" which I assume is an annual temperature change relative to the previous year. If I wanted to find the exact temperatures (based on NASA's ...
128 views

### Can the absorbtion of infrared around the 650 wavenumber in water be a substantial cause of converting that spectrum into other spectra?

CO2 absorbs around the 15 microns wavelenght or wavenumber 650, and radiates in the same but also a somewhat wider range. However, the top layer of the oceans seem to also convert that spectrum. ...
36 views

### sulfur hexafluroide as a greenhouse gas and its atmospheric journey

Maybe a simple question, but if sulfur hexafluoride is 6 times heavier than air then how does it get into the high atmosphere. All be it in low quantities now, but there is a large stock of the stuff ...
45 views

### Can air be slowed down by Fricton? [closed]

Can wind/air that is moving at average speeds be slowed down by the cause of Friction? Also, Can Air bubbles in water be slowed down because of Friction? Please cite your sources.
17 views

### Horizontal slowness in seismology

I am working on a seismology assignment and it starts with the fundamentals of seismology such as the wave equation, the slowness... such as the question below: write an equation describing the ...
75 views

### Why does relative humidity drop if I open the window in winter? What about the temperature drop?

I understand that 40% rel. hum. at 0 °C is less absolute humidity than 40% at 20 °C. However, assume that we have 2$~m^3$ of air. Both are 40% humid at 20 °C. Now we exchange 1$~m^3$ with air that is ...
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### Are pycnocline zones formed by or after mixing of sea and fresh water?

I trying to study Estuaries and Brackish water. A pycnocline is a layer of water that has the greatest density gradient in a body of water. Are they formed by or after mixing sea and fresh water?
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### PM1.0, 2.5 and 10 laser test values 1-5 ug/m3 but dust visible under sunlight. Does it make sense?

I wonder if household dust is visible and/or harmful. At home, it is visible under sunlight and it is small pieces the size of human hair or slightly smaller. The density by looking at it is ...
42 views

### What effect does river channelization have on the surrounding water table?

Correct me if I'm wrong, but most rivers lie where the water table protrudes into open air. In other words, the water table level is exactly the same as the river water level. (Wikipedia has a good ...
7 views

### Maintaining piping system for water recirculation on mini aquaponics project

I am thinking of demonstrating aquaponics system in my science project but i am little confused about piping system? What diameter of pipe would it be beneficial for continuous water recirculation. ...
17 views

### Why is the mean meridional mass stream function multiplied by g/2π?

I was reading this material on the mean atmospheric meridional circulation and the definition of the meridional mass streamfunction: http://www.geo.cornell.edu/geology/faculty/Cook/Hadley_book.pdf (...
68 views

### Relation between Magnitude of Greenhouse Effect and the Concentration of GHGs like $CO_2$

The Average Surface Temperature of the Earth is calculated by the following equation: $$\sigma T_s^4=\frac{(1-A)\Omega}{4}+\Delta E$$ where, $\sigma$= Stefan-Boltzmann Constant $T_s$= Average Surface ...
75 views

### Why are there so many “horseshoe lakes”, and are they really mostly in the US?

The Wikipedia disambiguation page Horseshoe lake lists 31 of them, of which 27 are in the US. Question: Why are there so many "horseshoe lakes"? Are they usually horseshoe-shaped, (or full ...
21 views

### Coarse grains in a sample of Rhyolite suggest that it formed by

Coarse grains in a sample of Rhyolite suggest that it formed by …… A-rapid cooling of molten rock materials at the Earth’s surface. B-slow cooling of molten rock materials at the Earth’s surface. C-...
482 views

### Why are January and February the coldest months although 21 December is the shortest day? [duplicate]

My question deals with the northern hemisphere only, obviously. It seems to me that January and February are the coldest months of the year. Water temperature is even more 'retarded': the seas are ...
30 views

### Are ocean waves diminished, enhanced or unaffected by underwater obstacles

Suppose you have a wave heading towards the beach, and under the water the surface rises suddenly then drops again back to the typical average slope of the coastline, does this have a muting affect on ...
85 views

### Is it possible to kickstart an hypothetical frozen earth with 0.6 ice albedo to an earth with an atmosphere, with just the sun at current distance?

Phase change of water at different pressures and temperatures tell us that with no atmospheric pressure 200 Kelvin (minus 73 Celcius) is enough to turn ice into vapor directly Wouldn't that suggest ...
40 views

### Would ultrasound be a valid method of mapping ocean floors given the perceived “gel” is ocean water?

I am a scuba diver, with a big idea that would require me to map various dive sites as I went to them and dove in them. The typical size and other implications of sonar technology would essentially ...
12 views

### How to calculate the specific humidity based on the saturated specific humidity?

I am using ERA5 data to drive the land surface model. One of the forcing required by LSM is specific humidity. We want to use the 2-m specific humidity. So how can I calculate the specific humidity ...
27 views

### Cleavage of minerals

What is the difference between 3-dimensional cleavage and cubic cleavage? I think, they are the same, but I am not sure about if I was right or not.
38 views

### How to identify a metallic rock that when wet 2 pieces of same rock coming into close contact caused an explosive [closed]

Nearly round metallic rock found in Arkansas, inside is marbled with shining metallic. After cleaning with dawn, water and soft tootbrush I matched 2 parts together and turned my back, heard a loud ...
27 views

Is there a good chart of the geothermal gradient but near the surface? I haven't been able to find one because they are primarily studied at larger depths, but I would like to know the equilibria at ...
38 views

### puzzling statement on earth history!

A Geology proffessor recently told me that around 200,000 years ago, when homo sapiens emerged, that "...all of civilisation can now fit on the width of a single strand of human hair." I am ...
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### If the earth's surface is negatively charged, why aren't objects close to the surface polarized?

A lot of misinformation about earth and it being a sink is spread everywhere, including what I was taught in school, I hope you well-informed folk can help me out. A sort of side-note, if anyone has a ...
24 views

### What was the oxygen concentration in the air during the late miocene period?

As the title says, I'd like to know what the O2 concentration was during the late Miocene period. I've tried to look this up but I'm having a hard time finding any conclusive data on it, or even any ...
28 views

I would like to know are questions on earthquakes on-topic on this site? For example, the devastating Earthquake of ASSAM INDIA in 1950 is rarely mentioned in Newspapers nowadays. The book "CODE ...
70 views

### Relationship between rainwater and solar radiation

I am an enthusiast in this area and reading some scientific articles on precipitation forecasting and solar irradiation, I was wondering if these two variables have any direct correlation or ...
33 views

### Question regarding an ice age caused by impact event(s)

If a hypothetical series of debris were to collide into a planet like Earth, I'm aware that dust could very well be sent into orbit, causing global cooling. If this were to happen, exactly how would ...
57 views

### Arabian Desert rock formation

I'm interested about this rock formation in Arabian desert. The rock looks like melting chocolate. Not sure where the exact Location, the source says it around Al-Ula, Saudi Arabia. Here the image ...
33 views

### What instrumentation and/or measurement is likely being shown in this video of giant Siberian craters/sinkholes?

The RT video The Permafrost Mystery: scientists explore giant Yamal Sinkhole (with English subtitles) shows scientists exploring the formation. In one scene after about ...
13 views

### What pollutants can be next to a wood processing plant with formaldehyde factory?

I used to live in an are with a large factory that processes timber then uses the splinters to create OSB and other wood composites. They also have a formaldehyde factory for producing their own ...
43 views

### Would it be possible, from the earth’s creation or during its various geomorphological changes, for all the following hypotheses to be probable?

I’m designing a fictional world setting for a game, and I would like to know whether it has a relative coherence based on science. (Don’t mind if it is an almost improbable scenario). Would it be ...
137 views

### Why is the average 1 Bar temperature on planets with a thick atmosphere proportional to the distance of the sun?

The temperature of a planetary body in space varies with the fourth-root of the power incident upon it, this is derived from the Stefan-Boltzmann Law. This is understandable when applied to a black ...
24 views

### How do geologists measure green house gass emmissions from large regions

I read here that volcanoes release about "0.6 billion metric tons of carbon dioxide per year". I wonder though, how scientists can estimate the emissions from large regions with geological ...
58 views

### Why is it that “With higher CO2, the dry gets drier and the wet gets wetter”?

The Phys.org article CO2 dip may have helped dinosaurs walk from South America to Greenland quotes Dennis Kent, "adjunct research scientist at Columbia University's Lamont-Doherty Earth ...
110 views

### How do we know the Arctic is just ice?

If I look at an Earth's map, the Arctic/North Pole always appears just like water. Evidently this is actually covered by ice, with an area depending on the time of the year. If this area is bigger ...
55 views

### What is oldest known coal source?

I read coal form in all geologic times but what is oldest know coal source?
22 views

### Hydrocarbon resources extension. How?

Pardon my naive question. But I heard this argument quite sometimes. One can find at the Schlumberger careers page the particularly interesting FAQ: “We are often told that oil is running out. Why ...
29 views

### High vertical resolution atmospheric sounding data

I'm currently doing some analysis using atmospheric sounding data available at University of Wyoming (I assume these are from the GTS network). But, the vertical resolution of the sounding data ...
2k views

### Other than tectonic activity, what can reshape a world's surface?

Take our world and look at its surface geography: we have continents and oceans, mountains ridges and canyons, and so on. To my knowledge, most of it has been shaped by tectonic activity (feel free to ...
32 views

### As small streams freeze solid, how can big rivers continue to carry water?

In areas of very cold temperatures (-20°C and below), it is not uncommon for small streams to freeze completely (as in, from top to bottom) and larger rivers to develop thick ice covers. However, ...
22 views

### Understanding certain phrases in the article “Footwall topographic development during continental extension”

I am currently attempting to read the article "Footwall topographic development during continental extension". The article and its abstract can be found here. When reading the abstract, I ...