All Questions

31
votes
4answers
5k views

How and why did the oceans form on Earth but not on other planets?

Earth is the only planet in our solar system that has copious amounts of water on it. Where did this water come from and why is there so much water on Earth compared to every other planet in the ...
30
votes
3answers
6k views

How would an icicle “grow” upwards?

The other day a friend of my dad's showed him a picture of an icicle that appeared to be "growing" upwards out of a crack in a sidewalk. There were no roofs, overhangs or vehicles parked near by... It ...
27
votes
6answers
6k views

How much will sea level rise if all the polar ice melts?

There are many movies about global warming, which say that melting of all polar ice would cause the whole world to suffer a huge flood. According my research (teachers, TV, Internet) people hold one ...
23
votes
3answers
31k views

Why is Earth's inner core made of an iron-nickel alloy?

This question has puzzled me for a while. I know that earth's mantle is made of different minerals, metals and rocks etc. and that has always made complete sense to me. But why is the inner core made ...
21
votes
6answers
88k views

Is there a difference between rock and stone?

I couldn't find the definitions from either source: Geology Dictionary Glossary of Geologic Terms
13
votes
2answers
45k views

Are clouds a gas, liquid, and/or solid?

Are clouds a solid, liquid, or gas? I have been looking online and they are often described ambiguously as a "mass". For instance, from NASA: A cloud is a mass of water drops or ice crystals ...
11
votes
1answer
651 views

Does the magnetic field really protect Earth from anything?

Many topics discussed here in Earth Science SE, tend to be about facts that are of consensus in the scientific community but not widely accepted by the general public. Instead, this one is widely ...
34
votes
5answers
3k views

How do we know the asteroids formed at the same time as earth?

In continuation of the question Why is Earth's age given by dating meteorites rather than its own rocks?, what evidence do we have that the asteroids indeed formed at the same time as earth? Is there ...
29
votes
2answers
6k views

Where on Earth is the magnetic field intensity stronger?

Are there places on Earth that have a strong magnetic field other than the magnetic north and south poles?
25
votes
2answers
686 views

Why do some planets have lots of $\mathrm{N_2}$ and others none?

Earth, Titan and Venus all have large amounts of $\mathrm{N_2}$ in their atmospheres. (In the case of Venus it's a small proportion, but Venus' atmosphere is very thick, and the total mass of $\mathrm{...
19
votes
2answers
309 views

Is there any consensus of what caused the Lusi Mud Volcano eruptions in Indonesia?

In May, 2006, the Lusi Mud Volcano in eastern Java, Indonesia came to life, smothering much of the surrounding land in mud. According to the article Indonesia's Infamous Mud Volcano Could Outlive ...
18
votes
1answer
354 views

How is global weather model skill measured?

The models I have in mind are the major global models such as the Global Forecast System (GFS) and the European Center for Medium range Weather Forecasting (ECMWF). These models produce numerous ...
17
votes
1answer
466 views

Why are weather kites no longer used (much) operationally?

Figure 1.12 from the IPCC AR5 WG1 report (reproduced below) illustrates the different instruments that have been used for weather forecasting. Most of the methods have been in continuous use since ...
17
votes
4answers
4k views

What would be the first thing which will render the Earth uninhabitable?

There are quite a few things which can make an otherwise habitable planet uninhabitable, and some of these will eventually happen, sooner or later: engulfed by its star when it becomes a red giant ...
16
votes
1answer
5k views

What do quasi-geostrophic and ageostrophic mean?

I know that geostrophic flow means straight wind flow that is balanced by the pressure gradient and Coriolis forces. But what do quasi-geostrophic and ageostrophic mean specifically?
15
votes
1answer
337 views

What is the predictability of El Niño/La Niña?

What is the maximum period of time into the future that an El Niño event can be forecasted with reasonable accuracy and what are the limitations in predicting the time limit?
15
votes
1answer
337 views

Can climate models reliably predict meteorological extremes?

This question is related to and extension of my previous question which was about the methodology used to predict future climatic extremes: What is the methodology to analyze future climatic extremes ...
14
votes
4answers
3k views

Why do greenhouse gases affect ocean temperature so much?

As I understand it, greenhouse gases absorb infrared radiation from the sun. Much of that radiation would otherwise continue and be absorbed on the planet surface in the ocean or on land. If CO2 ...
11
votes
1answer
495 views

What generates the microseism?

Looking at seismic noise around the Earth there is commonly a peak in the seismic noise around a frequency of 200 mHz. This peak is typically referred to as the microseism (an example is shown below)....
10
votes
1answer
107 views

Rainbow dynamics?

How would steam refract light compared to fog and how would the rainbow appear? Does the temperature of the water drop or ice crystal effect the rainbow in any way? I know the size of the water drop ...
9
votes
1answer
222 views

How are thermals really released?

Sailplane, paraglider or hang-glider pilots are used to say 'thermal is released by trigger'. The zones with contrasting albedos (land/water, plowed field/forest) or locations where terrain profile ...
7
votes
2answers
169 views

Does Earth risk losing its oceans to space due to global warming?

I read that we are facing the very real possibility of Earth's average temperature rising by more that 2 degrees Celsius by the end of the century. As I understand our planet is constantly loosing ...
7
votes
1answer
388 views

How will global warming affect climate systems like the ENSO or the MJO?

How will global warming influence climate systems such as the Madden–Julian Oscillation (MJO) or the El Niño Southern Oscillation (ENSO)?
5
votes
1answer
63 views

What actually happens to reduce the perceived color in a 'white rainbow“ or ”fog-bow"?

The image below is included in the BBC article Amazing white rainbow snapped over Scottish moor. Apparently this phenomenon is sometimes called a "fog-bow" and is characterized by the washing out of ...
4
votes
2answers
3k views

Interpolate Gaussian grids to regular fixed grids using bilinear interpolation?

I want to regrid GCM data available on Gaussian grids to regular grids, say at 1 deg X 1 deg. How to do this using CDO or Python ...
29
votes
1answer
2k views

What is the status of the Raymo & Ruddiman idea that Tibet cooled the Earth?

What is the current status of the Raymo & Ruddiman hypothesis that the uplift of the Tibetan Plateau during the Cenozoic cooled the Earth, resulting the current ice age(*)? cf. Raymo, M.E. and W....
28
votes
2answers
444 views

What would it take to confirm or refute the Snowball Earth Hypothesis?

Since Harland's sedimentary work and Budyko's models in the 1960s, geologists have hypothesized that the Earth may once have been completely frozen. There are various lines of evidence for this event. ...
25
votes
1answer
8k views

How much of a mountain is below the surface?

Is there some kind of math rule for how much does a mountain extend (depth) below the surface? I found an article like this http://www.livescience.com/6595-depth-himalayan-mountain-roots-revealed....
23
votes
3answers
21k views

Why are alpine river water green - blue?

I recently visited Slovenia where I saw several rivers with a strong blue-green color. Here is an example from one of the tributaries of the Soča river near Kobarid. The locals refer to it as an "...
21
votes
2answers
3k views

How do tropopause folds form and do they have any impact on synoptic scale weather?

What is the process that creates a tropopause fold? Do these features have any significant impact(s) on weather patterns or the atmosphere?
19
votes
1answer
58k views

Why are oceanic plates denser than continental plates?

In the theory of tectonic plates, at a convergent boundary between a continental plate and an oceanic plate, the denser plate usually subducts underneath the less dense plate. It is well known that ...
18
votes
4answers
1k views

Why does Earth have abundant oxygen in the atmosphere?

Because of photosynthesis, obviously. But then it's not actually that obvious after all, because photosynthesis is mostly balanced by respiration. We can summarise the processes of photosynthesis ...
17
votes
3answers
28k views

Why does the earth spin clockwise?

Why does earth rotate in a clockwise direction? Did a large meteor collide with earth causing earth to rotate? If that is what happened, could another, larger meteor cause earth to reverse its ...
16
votes
5answers
1k views

Is global warming being moderated by latent heat of melting polar ice?

I've only had a secondary education in physics, so bear with me, but with the greenhouse effect and all, wouldn't we be much hotter already if the ice melt-rate wasn't increasing, since more (heat) ...
16
votes
6answers
6k views

How to quickly or easily prove the world is spherical?

A relative of mine has recently introduced me to the modern flat earth theory, which she believes in. Setting aside for the moment that it is ridiculous, and that sending up some balloons with cameras ...
16
votes
2answers
12k views

Coriolis effect and Cyclones

The Coriolis force predicts that winds in the northern hemisphere should be deflected in a clockwise pattern and winds in the southern hemisphere should be deflected in an anti-clockwise pattern. Why ...
15
votes
4answers
10k views

What would be the effect of bringing seawater pipes to the Sahara desert?

This is a childhood dream. What would happen if pipes were installed (similar in principle to the Great Man-Made River, but for seawater) to continuously pump seawater into the Sahara desert. Let'...
15
votes
6answers
701 views

Does volcanic activity fluctuate?

According to this person's surmises, volcanic activity appers to be increasing. However, according to this report, volcanic activity is probably not increasing. My question is: Does Volcanic activity ...
15
votes
1answer
2k views

Why does glacier ice look blue?

The color of the ice observed in glaciers, icebergs and crevasses is often blue. However, ice cubes and industrial ice blocks are perfectly transparent or white if not. So. Why does glacier ice look ...
15
votes
2answers
892 views

How do the known abrupt climate change events fit into the xkcd Earth temperature timeline?

The xkcd "Earth Temperature Timeline" depicts the global average temperature during the past 20,000 years, based on the known data. We already have a question about the chart's general accuracy, but I ...
13
votes
3answers
3k views

Is it possible for Earth to experience Polar Shift?

Many accounts claim that the Magnetic Field of the Earth has been seriously degrading for the past centuries and we are currently in the process of the so called Polar Shift. How likely would it be ...
13
votes
3answers
2k views

What causes these banded clouds?

A set of banded clouds can be seen in MODIS imagery during several days in January and February over the Gulf of Maine. They tend to occur with very cold winds from the NW following storms. There are ...
13
votes
2answers
2k views

How to interpret hourly precipitation forecast?

How should I interpret the hourly precipitation forecasts? Most of the time, when there is rain in the forecast, the maximum Probability of Precipitation (PoP) in the hourly forecast is about the ...
12
votes
1answer
2k views

Should one extract wavelet from seismic or well log for the generation of synthetic traces?

Synthetics are generated by convolving reflectivity series with the known wavelet. I have seen most of the wavelet are extracted from seismic data itself. Is there any hard and fast rule, or can one ...
12
votes
2answers
4k views

What are baroclinic and barotropic waves?

I have a basic understanding of what baroclinic and barotropic mean but cannot seem to get my head around baroclinic waves and barotropic waves.
12
votes
2answers
1k views

When will glaciation resume? Has global warming delayed return to global cooling?

As far as I understand, we are currently living in the Holocene, an interglacial period of the Quaternary glaciation, i.e. the current ice age that has so far lasted 2.6 million years. The Holocene ...
12
votes
1answer
402 views

How is the Rossby Radius used to determine that synoptic weather systems are 1000-2000km across?

In one of his presentations, Sandy MacDonald (of NOAA and ESRL) talks about the Rossby Radius of Deformation in connection with the size of synoptic weather systems: he describes how it sets the ...
11
votes
1answer
213 views

What caused a fall in atmospheric oxygen about 1.9 billion years ago?

Using chromium isotopes geochemistry, Frei et al. 2009, describe in the article Fluctuations in Precambrian atmospheric oxygenation recorded by chromium isotopes that after the Great Oxidation Event (...
11
votes
1answer
215 views

What happens to the higher frequency content of the tremors associated with a volcanic eruption?

From [1]: The main characteristics of volcanic tremor depend strongly on whether a volcano is erupting explosively and on the intensity of the event. Long before an eruption, tremor is ‘narrow-...
11
votes
1answer
985 views

Why is ocean surface velocity around 3% of wind velocity?

Many introductory level textbooks suggest that, as a rule of thumb, the velocity of the ocean surface is around 3% the wind velocity at 10 meters above the sea surface. For instance, Ocean ...

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