COLD WAVE: What is Cold Wave | How Cold Waves are Formed | How Long Cold Wave Last | Effects of Cold Wave | Precautions to be Taken During Cold Wave.

Man Walking on a Road During Cold-Wave.

Written by Prevail Dias

COLD WAVE

1) What is Cold Wave?

It is a weather phenomenon that is recognized when there is a rapid and considerable fall in temperature within a 24 hours period. It is also called a cold snap or cold spell in some regions.

2) How Cold Waves are Formed?

During winter in the northern hemisphere, the sun shines vertically over the tropic of Capricorn in the southern hemisphere, this happens because of the tilt of the earth axis. In the northern hemisphere Due to this, there is very low or sometimes even zero solar radiation which enhances cold air masses during autumn & winter. The cold wave forms when cold air masses near the surface moves out from its source region in northern Canada and northern Asia. The core of a cold wave at the surface consists of a strong high-pressure center that forms during winter in the higher latitudes. The high pressure is associated with slow-moving winds. When these cold air masses get accumulated in any region there is a rapid fall in the temperature within 24 hours and the cold wave is formed.

3) What Causes Cold Wave in India?

During winter, the winds start blowing from north/ northeast to the south in India, this is because of the high-pressure system that develops north of the Himalaya & low-pressure system that develops south of India. Winds move from high-pressure to low-pressure. The western disturbance which gives precipitation in the form of rain, hail & snow is followed by a cold wave in northern India as when western disturbance moves away the winds start continuously moving from north to south over the region. Due to the continuous presence of these cool & icy winds and no disturbance in the flow of their direction cold wave forms in India. 

4) How Long Cold Wave Last?

The core of the cold wave at the surface consists of a strong high-pressure center. This system transmits cold air masses which are slow-moving as a result cold waves can last for several days. They are terminated when any disturbance changes the direction of the wind.

5) How Long Cold Wave Last in India?

Western disturbance plays a huge role in the formation and dissipation of cold waves in India. When western disturbance approaches north India the southeasterly winds begin to flow that causes a rise in temperature which in turn can eliminate cold wave. When it moves away, again the northerly winds start to flow which causes the temperature to fall and cold waves may form. Therefore cold waves can last longer in the absence of western disturbance.

6) Effects of Cold Wave

• Demand for electrical power and fuel increases by manifold.
• Due to low temperatures, some metals may become brittle.
• It causes death and injuries to humans and wildlife.
• Results in the failure of the transportation system.
• It causes hypothermia and frostbite.
• It can cause famines.
• It causes water to freeze inside the pipeline giving rise to many problems.

7) Precautions to be Taken During Cold Wave

• Always listen to the weather forecast before going out.
• Make a safety plan before going out.
• Dress in layers, it's better to wear multiple clothes.
• Wear a hat, mask, gloves, etc:-. All the body parts must be covered with warm clothes.
• It is highly recommended to stay indoor.
• Watch for the signs of hypothermia and frostbite.