Today it is foggy again. It came in quickly from the valley below and in minutes, the house was enveloped in a haze. It's a good day to stay inside and enjoy a strong cup of coffee. Ahhhhh.....cheers; let's blog!*Fog is a cloud that is in contact with the ground. Fog is defined as cloud which reduces visibility to less than 1 km, whereas mist is that which reduces visibility to less than 2 km.
The foggiest place in the world is the Grand Banks off the island of Newfoundland, Canada. Fog is frequent there as the Grand Banks is the meeting place of the cold Laborador Current from the north and the much warmer Gulf Stream from the south. The foggiest land areas in the world are Point Reyes, CA and Newfoundland, both with over 200 foggy days a year.
The foggiest place in the world is the Grand Banks off the island of Newfoundland, Canada. Fog is frequent there as the Grand Banks is the meeting place of the cold Laborador Current from the north and the much warmer Gulf Stream from the south. The foggiest land areas in the world are Point Reyes, CA and Newfoundland, both with over 200 foggy days a year.
*Fog forms when the difference between temperature and depoint is 5 °F (2.8 °C) or less.
Fog begins to form when water vapor(a colorless gas) condenses into tiny liquid water droplets in the air. Conversely, water vapor is formed by the evaporation of liquid water or by the sublimation of ice. Since water vapor is colorless, it is actually the small liquid water droplets that are condensed from it that make water suspended in the atmosphere visible in the form of fog or any other type of cloud.
Fog begins to form when water vapor(a colorless gas) condenses into tiny liquid water droplets in the air. Conversely, water vapor is formed by the evaporation of liquid water or by the sublimation of ice. Since water vapor is colorless, it is actually the small liquid water droplets that are condensed from it that make water suspended in the atmosphere visible in the form of fog or any other type of cloud.
*Fog normally occurs at a relative humidity near 100%. This can be achieved by either adding moisture to the air or dropping the ambient air temperature. Fog can form at lower humidities, and fog can sometimes not form with relative humidity at 100%. A reading of 100% relative humidity means that the air can hold no additional moisture and the air will then become supersaturated if additional moisture is added.
*Fog formation does require all of the elements that normal cloud formation requires with the most important being condensation nuclei. When the air is saturated, additional moisture tends to condense rather than stay in the air as vapor. Condensation nuclei must be present in the form of dust, aeresols, pollutants, etc. for the water to condense upon. When there are exceptional amounts of condensation nuclei present, especially hydroscopic (water seeking such as salt) then the water vapor may condense below 100% relative humidity.
*Fog reduces visibility and thus contributes to accidents, particularly with modes of transportation. Today, I had less thatn two car link of visibility. Notable examples of accidents due to fog include the July 28, 1945 crash of a B-25 Mitchell into the empire State Building, and the July 25, 1956 collision of the ocean liners: SS andrea Doria and the MS Stockholm.
*taken from WIKIPEDIA
A POEM: (I found this poem online; beautiful)
The Breathing - by Denise Levertrov
An absolute patience.
Trees stand up to their knees in fog.
The fog slowly flows uphill.
White cobwebs, the grass leaning where deer have looked for apples.
The woods from brook to where the top of the hill looks over the fog,
send up not one bird.
So absolute,
it is no other than happiness itself,
a breathing too quiet to hear.
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