Fog is a deject that touches the ground. Fog tin can be thin or thick, significant people have difficulty seeing through information technology. In some conditions, fog can be and so thick that information technology makes passing cars. Even monuments like London Span, in London, England, or the Gilded Gate Bridge, in San Francisco, California, are almost impossible to see in thick fog.

Fog shows up when water vapor, or h2o in its gaseous class, condenses. During condensation, molecules of h2o vapor combine to make tiny liquid water aerosol that hang in the air. You tin can see fog because of these tiny h2o aerosol. Water vapor, a gas, is invisible.

Fog happens when it'south very, very boiling. There has to be a lot of water vapor in the air for fog to form.

In order for fog to course, dust or some kind of air pollution needs to be in the air. H2o vapor condenses around these microscopic solid particles. Body of water fog, which shows upwards near bodies of salty water, is formed as h2o vapor condenses around $.25 of table salt.

Depending on the humidity and temperature, fog tin form very suddenly and then disappear simply as quickly. This is chosen wink fog.

Fog is non the same thing as mist. Fog is denser than mist. This ways fog is more massive and thicker than mist. In that location are more water molecules in the same amount of space in a fog. Fog cuts visibility down to one kilometer, pregnant it will forbid you from seeing further abroad than 1 kilometer from where you're standing. Mist can reduce visibility to betwixt 1 and 2 kilometers.

Types of Fog

There are several different types of fog, including radiation fog, advection fog, valley fog, and freezing fog.

Radiation fog forms in the evening when heat captivated by the Earth's surface during the day is radiated into the air. As heat is transferred from the ground to the air, h2o droplets form. Sometimes people utilize the term "ground fog" to refer to radiation fog. Ground fog does non reach as high as any of the clouds overhead. It usually forms at night. Fog that is said to "burn off" in the morning time dominicus is radiation fog.

Advection fog forms when warm, moist air passes over a absurd surface. This process is called advection, a scientific name describing the motility of fluid. In the atmosphere, the fluid is current of air. When the moist, warm air makes contact with the cooler surface air, h2o vapor condenses to create fog. Advection fog shows up more often than not in places where warm, tropical air meets libation body of water water. The Pacific declension of the U.s.a., from Washington to California, is ofttimes covered in advection fog. The cold California Electric current, which runs along the western coast of North America, is much cooler than the warm air along the declension.

Valley fog forms in mount valleys, unremarkably during winter. Valley fog develops when mountains forbid the dumbo air from escaping. The fog is trapped in the basin of the valley. In 1930, vapor condensed around particles of air pollution in the Meuse Valley, Belgium. More than than 60 people died as a issue of this deadly valley fog.

Freezing fog happens when the liquid fog aerosol freeze to solid surfaces. Mountaintops that are covered by clouds are frequently covered in freezing fog. As the freezing fog lifts, the ground, the copse, and even objects similar spider webs, are blanketed past a layer of frost. The white landscapes of freezing fog are mutual in places with cold, moist climates, such every bit Scandinavia or Antarctica.

Fog Catchers

Many ancient cultures collected water from fog by placing large pots nether trees and shrubs. Equally the water from fog nerveless on these objects, the pots nerveless the water. This method of water collection was constructive, but not as effective as collecting rainwater or other liquid water.

Today, engineers are working on more sophisticated means to collect water from fog. The about effective fashion has been the development of "fog catchers." Fog catchers are very large screens constructed in barren areas. Every bit fog glides in, water droplets form around the sparse screens and drip to the collection pools below. In one 24-hour interval, a single screen can collect more than a hundred gallons of water.

The village of Bellavista, Republic of peru, relies on fog catchers. Bellavista is an surface area that has little access to liquid water—no rivers, lakes, or glaciers are nearby. Wells dry out upwardly quickly. Water for irrigation and human consumption is threatened. Every year, however, huge fogs accident in from the Pacific Ocean. In 2006, the community invested in a series of fog catchers outside of town. Now, the residents of Bellavista have enough water to gargle trees and gardens, as well as provide for their ain drinking and hygiene needs.

Engineers warn that fog catchers will just work in small areas. However, engineers and politicians are working on ways to brand more powerful fog catchers that will perhaps reduce the need for people to rely so much on groundwater.

fog

A tall transport disappears into a thick fog.

Pea Souper
A "pea souper" is a type of fog that forms when water condenses effectually microscopic particles of coal. This fog is oftentimes a brownish-yellow colour, leading to the proper name. Pea soupers are common in areas that fire coal for energy.

The London Fog of 1952, which killed 12,000 people effectually the metropolis of London, England, was a pea souper. The Great Fog led to legislation that regulated the coal manufacture and air pollution in the Uk.

Grand Banks
The foggiest identify in the world is Grand Banks, a spot in the Atlantic Ocean off the island of Newfoundland, Canada. The cold Labrador Current from the due north and the warm Gulf Stream current from the due east create prime conditions for thick fog to form almost every mean solar day.

advection

Substantive

process of an air mass moving horizontally.

advection fog

Noun

water vapor that condenses as warm, moist air passes over a cool surface.

Noun

harmful chemicals in the atmosphere.

blanket

Verb

to cover entirely.

California Electric current

Noun

common cold body of water electric current that flows south in the Pacific Bounding main from British Columbia, Canada, to Baja California, Mexico.

climate

Noun

all atmospheric condition atmospheric condition for a given location over a menstruum of time.

Substantive

visible mass of tiny h2o droplets or ice crystals in Earth's atmosphere.

Noun

nighttime, solid fossil fuel mined from the world.

Substantive

process past which h2o vapor becomes liquid.

condense

Verb

to turn from gas to liquid.

dumbo

Adjective

having parts or molecules that are packed closely together.

Noun

tiny, dry particles of material solid plenty for wind to comport.

engineer

Substantive

person who plans the building of things, such as structures (construction engineer) or substances (chemical engineer).

flash fog

Substantive

h2o vapor that condenses and evaporates very quickly.

Noun

clouds at ground level.

fog catcher

Noun

device that collects water from fog.

freezing fog

Substantive

water vapor that freezes to solid surfaces.

Noun

thin coat of ice covering objects when the dew point is beneath freezing.

gas

Noun

state of matter with no stock-still shape that will fill any container uniformly. Gas molecules are in constant, random motility.

Substantive

mass of ice that moves slowly over land.

Gilded Gate Span

Noun

(1937) suspension bridge connecting the strait between the San Francisco Bay and the Pacific Bounding main.

ground fog

Noun

water vapor that condenses in a higher place land every bit the air cools following sunset. Too called radiation fog.

Noun

water found in an aquifer.

Gulf Stream

Noun

warm current that starts in the Gulf of Mexico and travels along the eastern coast of the U.S. and Canada earlier crossing the North Atlantic Ocean.

humid

Adjective

air containing a large amount of h2o vapor.

hygiene

Substantive

science and methods of keeping make clean and healthy.

industry

Substantive

activeness that produces goods and services.

Noun

watering state, normally for agriculture, past artificial means.

Noun

body of land surrounded by water.

Labrador Current

Substantive

cold ocean current that flows south from the Arctic Sea along the eastern declension of Canada. Also called the Arctic Current.

Substantive

the geographic features of a region.

London Bridge

Noun

bridge crossing the Thames River in London, England. There has been a bridge on the site for more than ii,000 years.

microscopic

Adjective

very pocket-size.

Substantive

clouds at basis-level, merely with greater visibility than fog.

moist

Adjective

damp or slightly moisture.

molecule

Substantive

smallest physical unit of a substance, consisting of 2 or more atoms linked together.

particle

Noun

pocket-size piece of material.

pea souper

Noun

fog that forms as water condenses around microscopic particles of coal.

prime number

Adjective

ideal or very expert.

radiation fog

Noun

h2o vapor that condenses above state as the air cools following sunset. Also chosen ground fog.

rainwater

Noun

atmospheric precipitation that falls as liquid water.

reduce

Verb

to lower or lessen.

common salt

Noun

(sodiumchloride,NaCl)crystalline  mineral often used as a seasoning or preservative for food.

Scandinavia

Noun

region and name for some countries in Northern Europe: Iceland, Norway, Sweden, Republic of finland, and Denmark.

bounding main fog

Substantive

water vapor that condenses effectually particles of sea common salt.

sophisticated

Adjective

knowledgeable or circuitous.

sunset

Noun

fourth dimension when the sun descends behind the horizon.

tropical

Adjective

existing in the tropics, the latitudes between the Tropic of Cancer in the north and the Tropic of Capricorn in the south.

urban heart

Noun

densely populated area, unremarkably a city and its surrounding suburbs.

valley fog

Noun

cloud that is trapped in a valley at ground level.

vapor

Noun

visible liquid suspended in the air, such every bit fog.

Substantive

move of air (from a loftier pressure zone to a low pressure zone) caused by the uneven heating of the Earth by the sun.

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    Writers

    Kim Rutledge
    Tara Ramroop
    Diane Boudreau
    Melissa McDaniel
    Santani Teng
    Erin Sprout
    Hilary Costa
    Hilary Hall
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    Kara W

    Educator Reviewer

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    Caryl-Sue, National Geographic Society

    Sources

    Dunn, Margery M. (Editor). (1989, 1993). "Exploring Your World: The Adventure of Geography." Washington, D.C.: National Geographic Gild.

    Last Updated

    Jan. 21, 2011

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