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• Wind – Moving air is called wind
• Global winds – different patterns of winds are observed due to temperature variations and earths rotation.
• Location on earth can be found out by latitude and longitude coordinates. It is measured from centre of the earth in degrees.
• Trade Winds – The warm air at equator rises up leaving behind the low pressure area. The air from the 0°to 30° latitude belt is relatively cooler and therefore it is under higher pressure. The pressure difference causes air to move towards the equator generating winds. Because of the rotation of earth these winds undergo change in direction from east to west and so these winds are also called tropical easterlies.
• Polar Easterlies: Air at the poles is colder than that at latitudes about 60 degrees. Here also rise in warm air creates low pressure area which is filled by colder wind from the poles, these are polar easterlies. These winds flow from 60°to 90° latitudes. Here also the rotation of earth causes these winds to change their direction from east to west.
• Prevailing Westerlies: These winds exists in 30 to 60 degrees latitude in the northern and southern hemispheres. They blow from west to east direction.
• Local winds – these winds occurs due to uneven heating of land and water
• Sea breeze, Land breeze – During day land heats up faster than ocean as a result the warm air at the land rises up creating low pressure area. The cooler air from oceans rush towards the land to fill its place producing wind. Such wind is called sea breeze. The picture is exactly opposite at night. At this time the land cools down early than oceans. Now the cool air from land rush towards the oceans producing wind called land breeze.
• Monsoon winds – these are similar to sea breeze and land breeze and occur seasonally. During summer, heating of land especially the desert regions is higher and so the cooler ocean winds blow from ocean towards the land in southwest direction. During this time heating of offshore is higher and so the air at this place contain a lot of moisture. Monsoon winds carry the moisture and causes rainfall in land. Similarly, during winter, land surface cools down faster than oceans and so monsoon winds blow from northwest colder region towards the oceans. They also carry little moisture and thus causes small amount of rain during winter.
• Thunderstorm – storms with thunder i.e. loud sound with lightning.
• Watch complete video on thunderstorm and lightning here
• Dos and donts in thunderstorm
  • During thunderstorms, open vehicles, like motorbikes, tractors, construction machinery or open cars, open fields, tall trees, elevated places, shelters in park are also not safe.
  • Donot carry umbrella in thunderstorm
  • Do not take shelter below trees, stay away from poles or other metal objects
  • You should sit with knees bent and heels close to buttocks i.e. in squat position, and place your hands on your knees with your head between the hands
  • Stay away from telephone cords, electric wires and metal pipes
  • Avoid bathing in thunderstorm as well as avoid contact with running water
  • Unplug electrical appliances like computers, television, refrigerator. You can keep electric lights on.
  • For the protection of buildings from the effect of lightning, a metallic rod can be installed in the walls during construction, which is taller than building height. One end in free while other is buried deep into the ground. This prevents building from lightning stroke.
• Cyclones – Cyclones are formed ocean water. it has a centre called the eye of the storm. It is a calm and clear area where there is no rain. It covers diametre between 10 to 30 km. High speed winds spiraling around the eye forms ‘eyewall’ of cyclone. This is the ring of thunderstorms where speed of wind is highest and most of the rain happens. The outer part of the cyclone is called ‘rain bands’. It is formed by clouds that spin around the eye making the cyclone bigger. It is known for sudden bursts of rain.
• Tornadoes – It is rapidly rotating column of air which extend from the thunderstorm to the ground forming dark funnel-shaped cloud. Most of the tornadoes are weak but the stronger tornadoes can travel at about 300 km/hr.