ather-forecasting.measuring temperatures three different scales can be used:
the scientifically used Kelvin-scale, also referred to as the absolute scale;
the commonly used Celsius-scale, which measures a temperature in centigrades; В»- the obsolete Fahrenheit-scale.
Humidityrefers to the amount of water vapour in the air. Warm air is capable to contain a higher grade of moisture, or humidity, than cold air. The maximum amount of moisture that air can hold at a specific temperature is known as "saturation". Clouds are the result of a rising mass of cool air. When the temperature of air falls, water vapour in the air will condense into droplets or ice crystals, thus forming clouds or fog.very often indicate an imminent change of weather. Rising clouds is an indication that the weather is about to clear; lowering or thickening clouds will indicate precipitation.is a cloud that touches the ground. Dense fog will reduce visibility considerably and is referred to as "thick weather". Is formed when the droplets or ice crystals in clouds have become sufficiently large to fall to the ground. Precipitation may take a variety of forms, for example rain, snow, drizzle, hail or sleet.is the most important factor that determines the condition of the weather. Wind is merely an amount of air that moves in a horizontal motion over the earth from an area of ​​high barometric pressure towards an area of ​​low barometric pressure.barometric pressure generally indicates that a gale or storm is approaching; rising pressure indicates the approach or continuation of fair weather.area of ​​low pressure is called a cyclone. A high-pressure area is an anticyclone.of the rotation of the earth, the circulations of winds in the northern hemisphere tend to be clockwise around areas of high pressure, and anti-clockwise around low-pressure areas.the southern hemisphere the directions of circulation are the opposite.is always named after the direction it is coming from, not blowing in.force is indicated by the Beaufort-scale numbers. These numbers, ranging from zero to force 12, refer to the wind-speed measured in nautical miles per hour.the navigator the wind direction and force are the most important aspects of meteorological conditions that are forecast in weather reports by weather stations.must always include an increase or decrease in force and any change in wind-direction. A change of direction is usually indicated by the terms "veering" and "backing". Veering wind changes in a clockwise direction. A backing wind changes in anti-clockwise direction.2. Answer the questions:
Why is the weather so important for mariners?
How can you measure the temperature? Do you know the difference between the scales mentioned above?
How does humidity depend on the temperature of the air?
How can you predict weather judging on the clouds?
What is the name for a cloud that touches the ground?
What kinds of precipitation do you know? What is the difference between them?
What is the influence of barometric pressure upon the weather-conditions?
Why is it so important to consider the place you are in while predicting the wind's movement?
How are the winds named?
10. How is the force of the wind measured?
. Exercise 3. Fill in the necessary word:
1. A change of in a clockwise direction is indicated by the word
"veering".
+2. is announced by a lowering or thickening cloudiness.
A change in is the most significant aspect in weather forecasting.
Saturation refers to the maximum amount of in air at a specific
temperature.
5. Circulation of is anti-clockwise around low pressure areas in the
Northern Hemisphere.
An irnminent change of weather is often indicated by .
The amount of air that moves from one area to the other is referred to as
8. can be ...
