78 votes

How do 'greenhouse gases' let heat in, but not let it out?

In a nutshell: The radiation that enters is shortwave radiation from the sun. Solar radiation is dominated by visible (as well as UV and near infrared) radiation with a wavelength mostly between 0.2 ...
  • 11.4k
45 votes

Why doesn't the 71% water of the earth dry or evaporate?

There are two ways this problem needs to be looked at. The first is more astronomy than Earth science. The Earth as an entire system is largely contained. Its gravity and magnetic field retains ...
  • 5,747
39 votes
Accepted

Why were both the sun and the moon red today?

Smoke. There was significant smoke across the USA, which attenuated the light from the sun/moon due to increased scattering. The smoke particles effectively cause the light to reflect in different ...
  • 12.9k
35 votes

Why is the temperature *still* rising?

"So much work"? Actually, compared to the global rate of greenhouse gas emissions, it's a case of "so little work"! From a scientific perspective the 'economists' solution' of carbon trading was ...
35 votes

Why aren't weather balloons left in the atmosphere permanently?

In addition to radiosondes that do a single ascent over a few hours, there are also driftsondes that stay in atmosphere for days or weeks, typically with their buoyancy set up to track a particular ...
  • 3,791
30 votes
Accepted

Why are mornings cooler than nights?

The Earth is always radiating heat to the space. But in the day the Sun delivers some heat. The net heat flux is then defined as the sum of those two factors. If the energy delivered by the Sun is ...
  • 628
28 votes
Accepted

Where is the calmest place on Earth?

The main resistance that winds have to their movements comes from the topography and surface obstacles. Therefore, as a general rule the closer to the surface the less wind you will find. But I guess ...
  • 17.3k
25 votes

Why doesn't the 71% water of the earth dry or evaporate?

Why doesn't 71% water of the earth dry or evaporate? The simple answer: Because it rains. The not so simple answer: By some estimates, the Earth has already lost about a quarter of its water, and it ...
  • 22.4k
25 votes

How do 'greenhouse gases' let heat in, but not let it out?

Gerrit's got the technical answer; I'm going to answer for a layperson. There are two ways objects lose heat. The first, and the way people are most familiar with, is conduction. Something touches ...
  • 351
25 votes

Why aren't weather balloons left in the atmosphere permanently?

It depends on what each weather balloon is measuring; what data they are capturing. Most weather balloons are released as specific times during a 24 hour cycle. Such balloons measure altitude, ...
  • 23k
24 votes
Accepted

What is the fastest the Earth has ever spun?

The speed of rotation of Earth is controlled by its angular momentum. And the conservation of angular momentum is a very serious law of physics (perhaps even stricter than conservation of mass). So in ...
  • 17.3k
23 votes

Why is the temperature *still* rising?

Your premises are flawed due to the lack of two critical details: Population rise; the sheer number of people on the planet that are consuming resources has risen to 7 billion people. Standard of ...
  • 12.9k
22 votes

How do 'greenhouse gases' let heat in, but not let it out?

To add to Gerrit's excellent answer, I'd like to add a couple more Images. Images always help clarify things for me. Firstly, this one shows the spectrum light coming from the sun in red. The peak is ...
  • 317
19 votes

Why are there no CO2 snowfalls on Earth?

There is more to phase change than just what you see on that graph. At temperatures and pressures that support multiple states (e.g. solid and gas) you have to look at the saturation vapor pressure ...
  • 14k
19 votes

Is the Unified Theory of Climate (Nikolov & Zeller) compatible with the AGW/GHG theory in any respect?

The paper you linked lists as its first reference Volokin and ReLlez, 2014; a paper that addresses the magnitude of the Earth's greenhouse effect. The validity of the paper you found largely hinges on ...
  • 3,334
18 votes
Accepted

What woud happen to me if I touched the aurora?

The lowest reaches of an aurora is ~100 km in the air. Your problem won't be the ionized gas, it'll be that the air pressure is close to zero. Also, aurora are very diffuse, with at most a few ...
  • 296
17 votes
Accepted

Why is WRF most often configured at 3:1 nesting ratio?

To understand why the nesting ratio of 3 is preferred to the nesting ratio of 2, it is important to understand the following two features of WRF: 1) Grids are Arakawa C-staggered: mass points are at ...
  • 4,953
17 votes
Accepted

Where do bad smells eventually go?

If you are smelling something, you are inhaling gases, particles, or a combination of the two. They don't normally build up in the atmosphere because of three reasons: transport/dilution (which you ...
  • 12.9k
16 votes

Why do greenhouse gases affect ocean temperature so much?

No, greenhouse gases do not absorb infrared radiation from the sun... the Earth is really the source of infrared. The amount of infrared energy from the sun that reaches Earth is insignificant. ...
  • 12.9k
16 votes

How to tell if a single day of weather is an anomaly or due to climate change?

I am interested in understanding how to tell if a single day of 'abnormal' weather is due to climate change or not. You can't. The day-to-day, locale-to-locale variations in weather are huge compared ...
  • 22.4k
16 votes
Accepted

Does rain (temporarily) deplete the surrounding atmosphere of carbon dioxide?

Here is the mass-calculation. We will consider a column of the atmosphere with a footprint of 1m × 1m. This column weighs about 10,000 kg (per square metre). In these days of climate change we will ...
16 votes
Accepted

Why snow is white?

Normal ice (as in refrigerated ice cubes) mostly has uniform crystalline structure - water molecules are in a perfect hexagonal grid, which enables it to be transparent. Not all ice is like that - ...
16 votes

Why does warm air "hold" more moisture?

Saying that warm air "holds" more moisture is technically incorrect, but is a common colloquialism. Let's break it down to the technicalities. Let's consider a glass of water with a vacuum (no air) ...
15 votes

Weak flashes of light in the sky

You were most likely seeing lightning (to be sure, a date/time and your location would be necessary). Lightning can be visible from quite a distance and storms can be incredibly active with lightning ...
  • 14k
15 votes

What keeps the different gases mixed in the atmosphere?

It's because gases also diffuse. If you separate two gases of different densities by a horizontal membrane, and then slowly remove the membrane, then the interface will diffuse. You can try this with ...
15 votes

Why snow is white?

Snow has a very high albedo. Actually, it reflects all wavelengths of the visible spectrum, whilst absorbing no particular wavelength. Hence the eye averages out the multiple reflected wavelengths as '...
15 votes
Accepted

Why (actually) is the night sky so bright in the city? How far up is that happening?

What's actually happening is scattering of light, both off of aerosol particles and nitrogen and oxygen molecules. For a review of quantitative models of light pollution as a function of distance ...
  • 5,922
14 votes
Accepted

What causes these banded clouds?

These are most certainly boundary layer rolls and not gravity waves. While there exists a visual similarity between the two phenomena, and both may exist in similar atmospheric conditions, they can be ...
  • 4,953
14 votes
Accepted

What causes a rainbow, its colours and its shape?

Short answer: A rainbow is formed when light enters a drop of water or an ice crystal and gets refracted and reflected back into an observer's eye. Longer Answer: Light travels at different ...
  • 2,157

Only top scored, non community-wiki answers of a minimum length are eligible