Meteorology: Condensation

What is the condition for dew formation at night?

Dew forms if the earth’s surface goes below the dew point.

What is the term used when the dew point temperature is below freezing?

Frost point.

What are Cloud Condensation Nuclei (CCN) larger than 0.1 mm used for?

They are favorable for producing clouds.

How many CCNs are there roughly for each 1 cm³ of air?

There are roughly 100 - 1000 CCNs.

What is the difference between hygroscopic and hydrophobic CCNs?

Hygroscopic CCNs cause condensation at RH < 100%, while hydrophobic CCNs cause condensation at RH > 100%.

What happens to visibility under haze conditions?

Visibility is reduced due to a lot of particulate matter in the air.

What is the visibility threshold for haze to become fog?

Visibility becomes fog when it drops below 1 km.

What is dry haze characterized by?

Small particles that scatter blue light better than red.

What is wet haze characterized by?

Large particles that scatter all wavelengths of light equally.

What is radiation fog?

Fog that forms at the earth’s surface due to infrared cooling.

When is radiation fog most common?

More common in late fall and winter.

What causes advection fog?

Moist air is advected over a cold surface.

What phenomenon forms evaporation fog?

Cold air moving over warm water.

What is a stratus cloud?

A cloud that is a uniform layer, Latin for 'layer'.

What type of clouds are Cirrus clouds?

High clouds that are thin and wispy, known as Mare's tails.

What defines the appearance of altostratus clouds?

A gray layer of clouds covering the entire sky, making the sun appear watery.

What are the characteristics of nimbostratus clouds?

Dark gray, wet-looking clouds associated with precipitation; visibility below is usually poor.

What is the appearance of cumulus clouds?

Clouds resembling cotton puffs with sharp outlines and a flat base.

What type of cloud is a cumulonimbus?

A thunderstorm cloud known for its vertical development.

How is sky coverage categorized when there is less than 1/10 cloud cover?

Clear (CLR).

What are geostationary satellites used for?

To determine clouds, moisture, and surface temperature.

Under infrared imaging, how do low clouds appear compared to high clouds?

Low clouds appear darker than high clouds.