Our World: What is Weather?

Watch the following video about weather. Answer the questions below after you’ve viewed the video.

Video Source: YouTube | NASAeClips | Our World: What is Weather?

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Okay, guys let's talk about weather. Basically, weather is the daily condition of the Earth's atmosphere. Weather is produced by the interaction of several factors, which include heat, air pressure, winds, and moisture.

Let's briefly look at each one of those factors.

Heat, transferred from the Sun, is absorbed by the Earth and spread through the atmosphere. Air temperature varies from place to place because the sun's rays strike the earth at different angles.

Air pressure is the measure of the force of the air pressing down on the Earth's surface. Air pressure depends on the density of the air. Denser air exerts more pressure than less dense air. Air pressure on the earth can vary considerably from location to location, due to unequal heating of the atmosphere. These air pressure differences cause the movement of air, which we call wind.

Finally, the amount of moisture in the air called relative humidity also influences weather moisture in the atmosphere condenses, causing clouds to develop and precipitation to fall to the Earth.

So have you come up with the difference between weather and climate?

I said earlier that weather is the daily condition of the Earth's atmosphere. But, what about climate?

Well for most of us, climate means a location is hot, cold, wet, or dry. You see, climate is the average weather conditions for a specific region over an extended period of time. The climate of any place is determined by two main factors: temperature and precipitation. The earth is divided into three major climate zones, based on the average temperature of these zones. They are the tropical, temperate, and polar zones.

Can you determine what climate zone you live in?

Have you ever been in a situation where the weather forecast called for sunny skies, yet it ended up raining all day long? You think, oh if I only had my umbrella.

But you know guys, the job of predicting weather accurately is a difficult one because our atmosphere it's constantly changing. You see, in order to predict the weather accurately for the hours and days ahead, weather forecasters must analyze information they receive from a number of sources including local weather observers, weather balloons, weather stations, and satellites.

What do you think?

  • List and describe some factors that contribute to the weather in an area.
  • Explain the difference between weather and climate.
  • Why is predicting weather such a difficult task?