Most Popular
1500 questions
17
votes
2 answers
What geophysical events can (temporarily) increase the Earth's rate of rotation?
My understanding is that the dominant factor behind the slowing of the Earth's rotation (i.e. the lengthening of the day) is tidal friction induced by the Moon's gravity. As seen on the graph below, the general trend is towards slower rotation of…
senshin
- 1,885
- 11
- 27
16
votes
1 answer
When a tectonic plate subducts, does any of the subducted material melt, or is it just the mantle above the subducted slab that melts?
I know that water released from oceanic crust causes melting of the mantle in subduction zones, but does any part of the subducted slab melt as well - such as the sediments on the slab or the basalt? If so, how do we know what material was melted…
Inkenbrandt
- 1,055
- 1
- 8
- 16
16
votes
3 answers
How much water is the atmosphere losing to space?
Up until recently, I was under a (wrong) impression that the amount of planetary cumulative water resources was finite as I believed its escape from the atmosphere was impossible. I believed that, unlike other planetary resources, it was impossible…
amphibient
- 263
- 1
- 2
- 9
16
votes
2 answers
Why is the inside of the Earth so hot?
I have heard that the Earth is made up of four layers, being the crust, the mantle, the outer core and the inner core. I have also heard that the Earth's temperature increases as you move from the crust to the inner core, with the inner core having…
Kenshin
- 7,576
- 12
- 42
- 81
16
votes
1 answer
Is the poleward migration of the maximum intensity of cyclones a result of tropical expansion or are there some other contributing factors?
In the recently published article by Kossin et al. (Nature, 2014, dx.doi.org/10.1038/nature13278), they show that there is a trend toward poleward migration of the location of tropical cyclone (hurricanes and typhoons) maximum intensity in most…
arkaia
- 15,447
- 4
- 52
- 122
16
votes
3 answers
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 have a more specific question.
The chart says…
Aaron Rotenberg
- 263
- 3
- 8
16
votes
1 answer
Why (actually) is the night sky so bright in the city? How far up is that happening?
The recent news reported by the New York Times, the BBC and the NPR web sites (for example) as well as in the Iceland Review and Iceland Magazine sites, about the shutting-off of Reykjavik's streetlights in order to better enjoy the Aurora (northern…
uhoh
- 7,105
- 2
- 30
- 91
16
votes
6 answers
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 fluctuate?
If it does, what would cause this…
Ben A. Noone
- 1,524
- 2
- 14
- 22
16
votes
2 answers
Great Pacific Garbage Patch Equilibrium Points
I was watching the science channel yesterday and the program mentioned the Great Pacific Garbage rim. I was struck by the illustration (and pretty much every subsequent animation/picture I've seen now has the same basic illustration) below:
Unless…
user153582
- 435
- 3
- 8
16
votes
2 answers
Are the processes of the rock cycle currently in dynamic equilibrium?
The standard representation of the rock cycle usually looks like this:
Does each stage of the rock cycle currently balance? That is, are the various processes in dynamic equilibrium, so that the proportions of the different rock types remain…
Poomrokc The 3years
- 1,171
- 3
- 11
- 18
16
votes
2 answers
Is spectrum of sunlight the same in the summer as in the winter?
Of course we receive less sunlight in winter, because the sun is lower in the sky, so the light has to travel through more atmosphere, and loses strength. Does this mean that the blue light is more scattered out?
Are the frequencies we receive in…
Marijn
- 2,513
- 5
- 19
- 35
16
votes
3 answers
Is 2015's record average temperature evidence that we are now experiencing runaway climate change?
2015 had the highest global temperatures on record, as discussed in this question, beating the last record ... in 2014.
Are we now in a runaway climate change regime, where zero further human impact on the environment will not prevent change to…
christopherlovell
- 459
- 3
- 9
16
votes
1 answer
Impact craters under water
What would be the resulting impact crater of a meteorite hitting bodies of water on Earth?
Let's take for example the impactor that resulted in Meteor Crater, Arizona. What would the impact look like if it hit a shallow sea? A deep ocean? Is there…
Gimelist
- 23,122
- 4
- 68
- 133
16
votes
2 answers
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 suspended in the
atmosphere. Clouds form when water…
neuronet
- 263
- 1
- 2
- 9
16
votes
3 answers
Why is the Ozone Layer 'hole' more pronounced in the Southern Hemisphere?
Lots of people comment that you have to use more sunscreen in Australia compared to European countries due to the hole in the ozone layer. (Even for roughly equivalent latitudes).
What would cause this imbalance? It can't be gravity, since that…
hawkeye
- 915
- 7
- 13