The water vapor or ice crystals coalesce, or come together, to form clouds. The particles in the atmosphere scatter more blue light than other colors which is why the sky appears blue but the small particles of clouds, scatter all the colors of light equally, which make up white light. So the gray hue is all about how thick the clouds are and how high up they are. The larger the water drops the more gray and the droplets are the biggest right before they fall as rain or snow.
This is because light gets absorbed versus being scattered, which means less light getting through. That is, a cloud gets thicker and denser as it gathers more water droplets and ice crystals — the thicker it gets, the more light it scatters, resulting in less light penetrating all the way through.
Skip to content. Watch Live. I Bridge Shutdown. Back to School. The air starts to cool as it rises higher into the sky, causing the water vapor to condense onto atmospheric dust from volcanoes, car exhaust and other sources. The resulting water droplets and ice crystals coalesce, or join together, to form clouds.
Unlike atmospheric particles that scatter more blue light than other colors making the sky blue , the tiny cloud particles equally scatter all colors of light, which together make up white light.
This movement produces clouds as the moist air is cooled across the entire front. The presence of stratus clouds usually means a chilly, overcast day. If precipitation falls from stratus clouds, it is usually in the form of drizzle or light snow. Cumulus clouds are large and lumpy. Their name comes from the Latin word meaning "heap" or "pile. Cumulus clouds are created by strong updrafts of warm, moist air. Most forms of heavy precipitation fall from cumulus clouds.
The weather they bring depends on their height and size. The higher the base of a cloud is, the drier the atmosphere and the fairer the weather will be. Clouds located close to the ground mean heavy snow or rain. Variations Clouds are also classified according to how high they are in the atmosphere and what kind of weather they produce.
The prefix "cirro-" refers to clouds that lie more than 6, meters 20, feet above the Earth. The prefix "alto-" indicates clouds whose bases are between 2, and 6, meters 6,, feet above the Earth, such as altocumulus and altostratus clouds. They are considered "mid-level" clouds and are mostly made of liquid water droplets, but can have some ice crystals in cold enough temperatures. The prefix "nimbo-" or the suffix "-nimbus" are low-level clouds that have their bases below 2, meters 6, feet above the Earth.
Clouds that produce rain and snow fall into this category. Nimbostratus clouds bring continuous precipitation that can last for many hours. These low-level clouds are full of moisture. Cumulonimbus clouds are also called thunderheads.
Thunderhead s produce rain, thunder, and lightning. Many cumulonimbus clouds occur along cold fronts, where cool air is forced under warm air. They usually shrink as evening approaches, and moisture in the air evaporate s. Cumulonimbus clouds gradually become stratocumulus clouds, which rarely produce rain. Clouds and Weather Certain types of clouds produce precipitation. Clouds also produce the bolt of electricity called lightning and the sound of thunder that accompanies it.
Lightning is formed in a cloud when positively charged particles and negatively charged particles are separated, forming an electrical field. When the electrical field is strong enough, it discharges a superheated bolt of lightning to the Earth. Most of what we consider to be single lightning strikes are in fact three or four separate strokes of lightning. The sound of thunder is actually the sonic shock wave that comes when the air, heated by the lightning bolt, expands very rapidly.
Thunder sometimes sounds like it comes in waves because of the time it takes the sound to travel. Because the speed of light is faster than the speed of sound, lightning will always appear before its thunder is heard. Meteorologist s measure cloud cover, or the amount of the visible sky covered by clouds, in units called okta s. An okta estimates how many eighths of the sky octo- is covered in clouds. Discover World-Changing Science. Thicker clouds look darker than thinner ones, which let more light through and so appear white.
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