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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:
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27 votes
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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 ...
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24 votes
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Why do clouds sometimes form a ring around the Sun?

This optical phenomenon is called a 22° halo which is a subset of other halos. This arises from sunlight refracting through hexagonal ice crystals, which can be found in high level cirrus clouds. ...
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22 votes
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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 ...
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18 votes

Why are clouds darker before it rains?

Fair weather cumulus clouds are white because there is a clear path for sunlight to reflect off the cloud and into your eye. Even when there are many of them, they are not vertically developed and ...
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18 votes
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Are clouds a gas, liquid, and/or solid?

The cloud that you see is a mixture of solids and liquids. The liquid is water and the solids are ice, cloud condensation nuclei and ice condensation nuclei (tiny particulates that water and ice ...
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17 votes
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Weight vs. Mass of Clouds

There are different senses of weight used within branches of physics and engineering. In the strictest physical sense "weight", is given by W = mg. i.e. weight is the force on an object due to gravity ...
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16 votes
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Are cloudy nights warmer than nights without clouds?

Is there a correlation between temperature and cloud, during the night? Very much so. It's called radiative cooling. Three factors come into play: cloudiness, relative humidity, and windiness. ...
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14 votes
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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 ...
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14 votes

What determines how fast clouds move?

Cloud particles are suspended in air, and their movement is governed by: Wind; whichever way the wind blows, the clouds go (with some exceptions such as lenticular clouds; thanks jamesqf comment). ...
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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 ...
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11 votes
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Great Lakes - cookie cutter clouds

There are a couple reasons for this. First, Lake Michigan is still cold this time of year, relative to the land that surrounds it. Warm air flowing over the lake will exchange heat and cool, ...
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11 votes
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What atmospheric radiative effects, if any, do contrails cause?

We had a surprising opportunity to study this very question during the period of September 11-14, 2001, when all air traffic was grounded across the United States. The research was inconclusive, but ...
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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 ...
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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 ...
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11 votes
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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 ...
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10 votes
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Snow from Fire: Could graupel, or even snow, fall from pyrocumulus clouds?

It is likely snowing somewhere in these clouds and graupel exist transiently on their way to becoming hail, but its not likely that you will see either at the surface. You can make a first order ...
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10 votes
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Do clouds float on anything?

Clouds are made up of very tiny liquid water droplets that have small fall speeds. This means that with just a little bit of upward velocity in the wind, the cloud water can remain aloft and appear ...
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10 votes
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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, ...
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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 ...
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9 votes
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What atmospheric phenomenon am I seeing in this photo?

You are seeing an older jet contrail and its shadow. You can also see some newer contrails, and maybe even some older ones. Contrails are not necessarily continuous. For example, the contrail that ...
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9 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 ...
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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 ...
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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 ...
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8 votes
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What are the advantages in looking at an OLR map versus looking at IR satellite imagery?

First OLR map is usually graded in flux units (W/m2) thus it is quantitative data, not just a visual picture. Clouds themselves are not a very reliable indicator of high convection and thunderstorm ...
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8 votes
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What is this cloud formation?

This a type of arcus cloud called a shelf cloud and is caused by moist air rising over cool thunderstorm outflow. These clouds can look quite dramatic but do not pose any threats themselves. However,...
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8 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 ...
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8 votes
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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 ...
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8 votes
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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 ...
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