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29

The clouds can be seen moving but of course it's subtle at first glance. Frame 16: Frame 20:


27

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 Pacific Ocean near North America. The North Pole is in the upper left corner of the image, reflecting the orbital tilt of Earth from the vantage point of the ...


24

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. Light that would otherwise not make it to your eye enters an ice crystal and then exits at an angle of approximately 22 degrees. This produces the arc of light ...


20

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 up moisture from evaporation. After it passes the coast, the mountains cause the air to rise. As it does so it cools. Colder air can hold less water vapour than ...


17

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 condense on). The invisible part of clouds that you cannot see is water vapor and dry air. The majority of the cloud is just plain air in which the invisible ...


16

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 alone. Clouds are not "weightless" in that sense, since they are not far enough away from the Earth to escape its gravitational pull. The reason that clouds ...


15

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. Nighttime radiative cooling is greatest under clear skies, low relative humidity, and light or no winds. The temperature drop (in degrees per hour) can be a factor of ...


15

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 photons can still scatter off of them to you. As cumulus develop into towering cumulus and cumulonimbus they become horizontally widespread and quite high (the ...


14

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). The wind is often strongest in the upper troposphere (there are no clouds in the upper atmosphere), so upper tropospheric clouds will move faster than near-...


11

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, reducing its buoyancy, which will alter the heights at which clouds will form and inhibit lift for surface parcels to achieve that height. That helps explain the ...


11

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 they found that there was a 1.8 degree celsius increase across the US during this time frame compared to the three days before and after that time frame. ...


11

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 distinguished by two key characteristics: Unlike gravity waves, which develop in the downwave direction (perpendicular to the crest), boundary layer rolls ...


10

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 to float. Clouds are not always static blobs -- if you watch some clouds you will see that air can flow through them, condensing into new cloud where it goes in ...


10

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 called L1, more than one million kilometers away!!!. The rotation of the Earth in the animation makes it difficult to distinguish the movement of the clouds, but ...


10

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, moist air is forced upward by both wind from behind and the mountain barrier in front. The upward movement forces cooling and condensation of vapor into clouds. ...


10

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 altitudes are strong and flow over the cold air from below. The combination of the warm air and the moisture is usually unevenly distributed hence the trail of fine ...


9

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 appears to be horizontal in the image below appears to magically appear near the left end of the image. That's what you are seeing in your image, but in this ...


9

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 approximation of a pyrocumulus cloud by putting a very strong heat source at the surface in an environment otherwise favorable for severe convection. What you'll ...


8

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 activity. They could form elsewhere and get blown into a dry region. Also with an OLR map students would not be distracted with the shapes of the clouds. AIRS ...


8

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, they can signal the presence of strong winds behind the gust front. These clouds can often be associated with strong convection -- squall lines, supercells,...


8

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 little ways west of the mountain is ocean. The location is the mid-latitudes and the prevailing wind is from the west. Air along the surface travels above ...


8

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 and measure the air pressure. Fog is a cloud, and pressure likely hasn't changed as much as it does in the vertical direction. As far a forming a cloud, it is ...


8

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 moisture, they can occur on their own (as in this case), apart from other cloud features. All cloud growth depends on the condensation of water resulting from air ...


7

These are some of the most recent areal photographs taken of this phenomenon. The Morning Glory clouds are the visible manifestation of atmospheric Internal Solitary Waves (see the schematic in (b) below). They propagate on a sharp interface between a relatively dry layer ambient air above and a layer of sea water laden air pushed in from the night before ...


6

This is an interesting question and I feel the best answer is "a little bit of both". Consider your picture without the overshooting top and just the anvil. The tropopause is clearly defined as the anvil spreads out horizontally against the static stability of the stratosphere. Now let us consider a single parcel in the updraft, accelerating upward due ...


6

Noctilucent clouds form during summer at high latitudes, such as between 50 and 70°N. They are noctilucent because at their high elevation (80 km), the sun is still shining, although the sun is below the horizon at ground level. Due to this high elevation, you can see them from several 100s of km south of their actual location. This means the ideal ...


6

I don't believe such a formula or table exists (but admittedly, I have not attempted a lit review in this subject). Sky coverage (cloudy, mostly cloudy, etc) is a the fraction of the sky covered by clouds, not how much light penetrates to the surface. Even with a mostly cloudy day, all it takes is one break in the clouds between the sun and your instrument ...


6

There's no hole. Are you referring to the sky inside the halo looking darker than the sky outside? If so, the same phenomenon, known as Alexander's band, happens with rainbows. The reason is that light can only deviate through a certain range of angles when it passes through the ice crystals that cause the halo. In particular, light can spread outwards from ...


6

It can be measured in units of energy per surface area, for example, kWh/m2. The official SI name would be radiant exposure but I haven't seen that phrase used in a climate or weather context. For example, here is a map by NREL of average radiation per day in the US for July: (Source: National Renewable Energy Laboratory) And here is a map for Sweden for ...


6

A cloud isn't solid any more than a bunch of dust picked up by the wind is solid. It's mostly air, but what you see is tiny suspended particles, so it's no more a liquid than a bunch of dust blowing in the wind is solid. The entire cloud needs another definition because it's so diffuse. Suspended very tiny drops of water or ice crystals is probably the ...


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