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29 votes

Why clouds are not moving in NASA's video of the Moon passing in front of the Earth?

The clouds can be seen moving but of course it's subtle at first glance. Frame 16: Frame 20:
Adam Caviness's user avatar
27 votes
Accepted

Why One Side of Mountain Range is Lush

The Cascade Mountain Range in the US Pacific Northwest is a good example to use to explain this. The predominant wind direction is from the West - over the Pacific Ocean. The air over the ocean picks ...
haresfur's user avatar
  • 4,429
27 votes
Accepted

Why clouds are not moving in NASA's video of the Moon passing in front of the Earth?

They are moving, but not fast enough to notice at the distance shown. From the NASA page: These images were taken between 3:50 p.m. and 8:45 p.m. EDT on July 16, showing the moon moving over the ...
gerrit's user avatar
  • 11.6k
23 votes
Accepted

Why aren't lenticular clouds moved by the wind?

Clouds form when particular conditions of temperature and humidity intersect. In the case of lenticular clouds, those conditions occur at specific locations slightly downwind from the tops of ...
Spencer's user avatar
  • 3,548
12 votes
Accepted

What is this spaceship-shaped cloud?

The image shown is a lenticular cloud, a type of cloud often observed around significant topographical features such as the mountain peaks shown in the photo. Depending on the local atmospheric ...
dplmmr's user avatar
  • 1,144
12 votes

Why are the clouds white and Australia black in weather satellite infrared images?

I had a very similar question in a job interview! The only difference is that it was an image from SEVIRI on Meteosat. The imager on HIMAWARI is called the Advanced Himawari Imager (AHI). The AHI ...
gerrit's user avatar
  • 11.6k
12 votes
Accepted

What is this narrow band of clouds?

Given the weather patterns, it looks like Google Earth is generating those cloud overlays from some recent (i.e., the current day) satellite images. That line is suspiciously close to the edge of ...
Deditos's user avatar
  • 3,940
11 votes

Why clouds are not moving in NASA's video of the Moon passing in front of the Earth?

The image is real, and the clouds are moving, they just move slow, as clouds do. The unnatural appearance arise because they are taken by DSCOVR at an extraordinarily large distance, from a place ...
Camilo Rada's user avatar
  • 17.6k
11 votes

Why are the clouds white and Australia black in weather satellite infrared images?

It is likely because there is already a conversion from the raw data to the grayscale image posted on the CWB website. From this online course (emphasis mine): [...] using the mathematics behind ...
Jean-Marie Prival's user avatar
10 votes
Accepted

Are these clouds exhibiting gravity waves?

These are rotor clouds, and are manifestations of "Lee Waves", a particular kind of internal "gravity wave" (better defined as "buoyancy effect"). Forced convection helps form these clouds as warm, ...
Knob Scratcher's user avatar
10 votes

How do these cloud forms grow?

Looks like Cirrus Fibratus (Ci fib) to me. See e.g. Wolkenatlas or Clouds Online. Regarding the formation of Ci fib, Name of Clouds says: Cirrus fibratus clouds are formed when winds at high ...
FuzzyLeapfrog's user avatar
9 votes

Why One Side of Mountain Range is Lush

I'll augment the other answer with an example. Consider a theoretical north-south oriented mountain range that rises 2000 m above sea level and the land on either side of the range is at sea level. A ...
casey's user avatar
  • 14.1k
9 votes
Accepted

What is this ring of cloud?

It might be a smoke ring, but it's not known for sure. There have been several sightings of similar objects over the past few years. A ring was seen in Leamington Spa in 2014. Theories about its ...
HDE 226868's user avatar
9 votes

Why is there a clear space between the ground and the cloud base?

In my recently updated answer to the question: What the humidity metric is hiding? I cite a news article, originally dated 31 January 2020 : Oppressive, humid conditions for southern Australia as ...
Fred's user avatar
  • 24.6k
9 votes

Can clouds be formed without a pollen particle's role?

Pollen is one of many types of cloud condensation nuclei (CCN). So can you make clouds without pollen? Yes, but you still need other sources of CC. Don’t fall into the false dilemma that pollen is a ...
BarocliniCplusplus's user avatar
8 votes
Accepted

Making clouds for science project

To form a cloud, generally speaking, pressure does not play a significant factor (with the exception of the effect on temperature). If you want to prove that to yourself, go outside when it is foggy ...
BarocliniCplusplus's user avatar
8 votes

Could this cloud be artificially formed?

There's not much context, but my guess is that this was a cavum cloud (a.k.a. punch hole or fallstreak), that was caused by an aircraft. The UK Met Office describe how these form: They form in ...
Deditos's user avatar
  • 3,940
8 votes
Accepted

Why does Earth's atmosphere have a whiter color near the horizon?

The reason is that the horizon is paler is that we are seeing all wavelengths of sunlight equally scattered into our eye from along the line-of-sight to (and beyond) the horizon, so the horizon ...
David Bailey's user avatar
7 votes

What would a planet's sky look like with different chemical compositions, such as low nitrogen, high methane etc?

Except for Rayleigh scattering (Is the color of the sky the same everywhere on earth?) gases typically do not add any color to atmospheres, they are usually transparent in visible light. The Halogen ...
Eubie Drew's user avatar
  • 1,207
7 votes

Estimate cloudbase height

You are right, you can't get cloudbase height without 3D data. You can do that using radiosondes. However, if your weather station has a ceilometer, then you don't actually need many calculations. ...
BarocliniCplusplus's user avatar
7 votes

Why do clouds dissipate when mixing with dry air?

You may be assuming cloud droplets are in a "rest" state or some finite ordered state. Cloud droplets are actually growing/shrinking continuously as each molecule of water reacts to its ...
f.thorpe's user avatar
  • 13.5k
6 votes
Accepted

Calculate the Top of a Cloud

The formula you found comes from the barometric formula. It assumes a hydrostatic atmosphere (no vertical accelerations), a constant temperature with height (or a mean temperature) and uses the ideal ...
Lukas's user avatar
  • 438
6 votes
Accepted

Have these optical satellite ground station locations been chosen for clear skies?

Yes, mean cloud cover is routinely measured from satellites. Like all satellite data (and in fact all measurements), it does have an uncertainty, but for the purpose of this question the satellite ...
gerrit's user avatar
  • 11.6k
6 votes

What mechanism leads to these spectacular iridescent patterns in clouds labeled as a "Fire Rainbow"?

The top two pictures are of iridescence in a pileus (AKA "cap cloud") above a growing thunderstorm. Pileus clouds form when a storm updraft pushes up through a layer of moist air, and lifts ...
Mike Kavulich's user avatar
6 votes
Accepted

What might cause these "wave clouds" near the horizon? Could it be gravity waves?

Identification of the phenomenon based solely on the photograph is unfortunately inconclusive, although several reasonable possibilities exist. While a wavelike structure is apparent, exact ...
dplmmr's user avatar
  • 1,144
6 votes

There are cloud identification guides, are there also (guided) rock identification websites?

I looked through your step-by-step cloud identification guides, and they seem pretty easy. The overwhelming criterion for which cloud it is is "how does it look", with the addition of the obvious "is ...
Gimelist's user avatar
  • 23.1k
6 votes

How to tell the difference between real rain and fake rain (cloud seeding)?

What differences exist between natural rain and human “rain”? The only physically measurable difference between rain from seeded clouds and unseeded is in the seeds/ cloud condensation nuclei/ ...
Communisty's user avatar
  • 1,064
6 votes
Accepted

Are these plane trails seen from satellite

Under the right conditions (in a basic sense, locally high relative humidity; see also this discussion on this site regarding contrail formation), the clouds initially formed by contrails may persist ...
dplmmr's user avatar
  • 1,144
5 votes

Have these optical satellite ground station locations been chosen for clear skies?

This is just supplemental information to the accepted answer by @gerrit I took the ESA cloud cover fraction map provided there, and added dots that represent the approximate locations of the ground ...
uhoh's user avatar
  • 7,074

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