Introduction
This paper looks at the different types of fog in the United States, the conditions needed to produce fog, the measures the government takes to reduce fog related accidents and their effectiveness. The purpose of this paper is to bring awareness to people who reside in places with fog as well as continue the conversation on how to better reduce fog related accidents.
Types of Fog Fog is moisture trapped close to the ground when warm air cools and becomes saturated with moisture. The locations and circumstances that created the fog are what differentiate between the types. The five different types of fog that this paper will look at are Radiation, Advection, Freezing, Evaporative and Hail.
Radiation
Radiation Fog is formed as
…show more content…
This can occur inland over a lake or river, but it is very much a staple of coastal living. Four of the foggiest places in the United States have advection fog, Point Reyes California, San Francisco California, Cape Disappointment Washington and Mistake Island Maine. For example off of the California coast off shore winds blow warm moisture filled air across the colder Pacific Ocean shoreline and when the moisture condenses it creates fog with a horizontal movement from the wind. Advection fog can form very quickly if the air mass moving in has been preconditioned. In this type of fog anti cyclones play a larger role. They create an inversion or a cap over the surface, which means that as the warm air rises it hits the cap, cools and returns back to the surface condensing all the moisture it carried. Anticyclones also contribute to wind shear, which is when the wind changes with elevation.
Freezing
Freezing Fog is when water droplets condense towards the surface where the temperature supercools the moisture and once the water droplets settle on a surface they freeze. This type of fog is most common up in the mountains where the temperature drops to freezing. This fog is especially dangerous because it can coat the roads in ice, which contributes to dangerous road conditions. This has been seen in Louisville Kentucky and other similar locations. Due to the temperatures needed to create Freezing Fog it is more likely to occur in the Polar Regions.
The concept of lake-effect snow is rather simple. It starts when cold arctic air from Canada moves southwest across the great lakes, which are warmer than the air. As the air moves across the lakes evaporation occurs. The moist air is cooled as it is lifted up and then turned into snow. This snow does not stop until the cold arctic winds stop drifting across the lakes. Hills and valleys on the shore of the lakes intensify the amount of snow an area receives. The shore of the lakes as well as, any hills or valleys, cause the masses of moist air to slow down and “pile up”.
Ocean currents have been known to change direction or slow down. The heat that escapes from the oceans is in the form of water vapor, the most abundant greenhouse gas on Earth. Yet, water vapor also contributes to the formation of clouds and has a net cooling effect.
There are numerous stages that take place simultaneously in the hydrologic cycle and this includes evaporation. This is when the water alters from a liquid state into a gas. The damp air from the water rises into the atmosphere and when it cools, the vapor condenses and shapes into clouds. But those billows are not the only form the vapors make; it can also materialize as dew, fog and mist, which blanket the Earth, characteristically on a rainy or humid day. Evaporation takes place when water changes from a liquid state into a gaseous state, and ascents out of the pores of the earth and into the atmosphere as a vapor (“How”). While evaporation is taking place, condensation is also occurring. When the temperature in the air plunges, the clouds become heavy and as a result they relieve themselves of the extra weight, which is called precipitation. This produces rain, hail, snow and sleet, conditioned upon the temperate. As the precipitation falls, it enters the surface of the ground and percolates into the soil, which is called infiltration. The more porous the land is, the more the infiltration can take place. However, the ground cannot hold all of that water and floods. The excess rainfall, which is also called runoff that has not been absorbed makes its way into bodies of water, such as small ponds, rivers, lakes and parts of the ocean (“Summary”).
Furthermore, weather is conditions that occurred very recently or are currently happening at a particular location. For example, people might say, “The sky is really clearing up!” or maybe, “It snowed 6 inches last night.” The current temperature, dew-point, relative humidity, cloud cover, and precipitation all have to do with the weather. The fundamental cause of weather is the effect of the Sun and the Earth due to the fact that
Lake effect snow is a very interesting mesoscale convective phenomenon that occurs mostly during the heart of the winter season and adds greatly to the annual snowfall that areas
Hurricanes form over the ocean. Easterly waves, what hurricanes develop from, are long, narrow regions of low pressure which occur in ocean winds called trade winds. At first, these easterly waves can grow into something called, a tropical depression. A tropical depression occurs when winds are up to 31 mph. Then tropical depressions can be upgraded into a tropical storm if the winds reach speeds of 74 mph or less. Then finally a the storm can be bumped up into a hurricane if the winds reach 75 mph.
This quote simply means that it's one of those days when fog is followed by
One of the most dangerous environment issues Southern California is facing today is air pollution. This includes the burning of fossil fuels and natural disasters. Los Angeles is one of the most polluted cities in the world, and the most polluted city in the United States. I will research information about the causes, the effects, and the history of air pollution in the Los Angeles. For my research, I have relied mostly on, the school’s database and library, as well as current events.
Wind tunnel and flight tests have shown that frost, snow, and ice accumulations (on the leading edge or upper surface of the wing) no thicker or rougher than a piece of coarse sandpaper can reduce lift by 30 percent and increase drag up to 40 percent. Larger accretions can reduce lift even more and can increase drag by 80 percent or more. (AOPA, 2002, 2).
A simple definition of precipitation is any form of water that falls from clouds in the sky. Precipitation includes rain, snow, sleet, freezing rain, and hail. So with that being said let's take a look at these different forms of precipitation.
Photochemical smog is an environmental problem that develops when primary pollutants interact under the presence of sunlight to produce a mixture of many different and hazardous chemicals known as secondary pollutants. Photochemical smog is formed by the reactions of automobile exhaust in the presence of sunlight. The term “smog” is derived from the words smoke and fog. It is also known as Los Angeles smog.
in), but high humidity results in fog and dew. In the north deeep canyons have
Rain forms when water vapor condenses and falls, the more it condenses the more it falls. Some raindrops are not pure and are filled with other materials, this is known as acid rain. Acid rain is a huge problem all over the world. Acid rain is mixture of chemicals, like fossil fuels and the atmosphere, it then comes down as rain, snow, hail, and sleet. The burning of fossil fuels is the main cause of acid rain. When oil and coal are burned they create sulfur dioxide, nitric oxide, and nitrogen dioxide. (" Acid Rain | US EPA") The mixture of all the chemicals and heavy winds blow the compounds across many borders.
Air is composed of molecules. Air is matter. It has mass and takes up space. Air is composed of different gases such as nitrogen, oxygen, carbon dioxide, water vapor, and other gases. Air molecules are in constant motion. As they move, they come in contact with surfaces. Air molecules push and press on the surfaces they contact. The amount of force per unit area that air molecules exert on a surface is called air pressure. (What is Air Pressure 6) Air pressure is caused by all of the air molecules in the Earth's atmosphere pressing down on the Earth's surfaces. We can measure air pressure to help us predict weather conditions around the world. Temperature also affects air pressure because air contracts when it cools and expands when it is heated. So if air above a region of Earth cools, it does not extend to as high an altitude as the surrounding air. In this case, its pressure at higher temperature is lower than in the surroundings even when the pressure at the surface is the same as in surrounding areas. Then air flows into the cooler region at high altitude, making the total weight of air above the region greater than in the surroundings. This is a "high". The cool air descends to the earth's surface. Near the surface, the falling air spreads out,
A thunderstorm that produces large amounts of precipitation which reaches the ground should have deep moisture stratums in unstable conditions, causing enough convection to be restricted to the electrification level of the atmosphere, or being lifted by orographic or frontal systems (Rorig and Ferguson, 1999). However, some thunderstorms produce small amounts of precipitation or none. Colson (1960) explained this phenomenon as a result of high-level thunderstorms with high cloud bases where the appropriate conditions for triggering lightning flashes accompanied by precipitation are situated in the upper levels. Rorig and Ferguson (1999) analysed the synoptic patterns of dry thunderstorms and concluded that low moisture levels in the inferior part of the atmosphere coupled with high instability, leads to the evaporation of precipitation prior to reaching the ground level, this way reducing the moisture content of the underlying surface.