Weather Factors (Understanding the Weather continued)
They can either be grouped in large clumps but separated by blue sky during a sunny day or they can come in giant clumps with a somewhat darkened blue sky. Based on the appearance of clouds, we can more or less tell whether or not we will have good weather for the day. This is likely to be the same method people used before the development of weather instruments. But what if we want to know what the weather will be like tomorrow? Or the day after? In order to predict what the weather will be like farther into the future, we have to look beyond the clouds!
It was mentioned earlier that to accurately understand and predict the weather, we will have to understand other factors as well. The first of those is air pressure, which is the weight of the air that presses down onto the earth. This pressure can change depending on time and place. Usually, air moves from areas of high pressure to areas of lower pressure, causing the air to move and make wind. We measure air pressure by using a barometer.
The wind is the movement of the air around the earth in a horizontal motion. The vertical movement of wind creates clouds. Horizontal movement is due to the atmosphere's natural attempt to relieve pressure. Sometimes wind blows furiously. This happens when there is a big difference in pressure from one high point to the next low point. Other times, when the difference is less, the wind blows softly. There are several types of winds in our weather system and these are due to certain factors that affect it. We measure wind speed with an anemometer.
Next on our weather factors is temperature. The definition of temperature tells us that it is the measurement of how hot or cold something is. When it comes to weather, we measure the temperature of the air. If the air temperature is hot, the moisture of the air is evaporated and brought upwards towards the clouds. If the air temperature is low, then the vapor remains and the air stays cool. We measure temperature using a thermometer.
Moisture is the final factor looked at when predicting the weather. The air that surrounds the earth is filled with moisture, or tiny bits of water that we cannot see. We measure the amount of moisture in the air by its humidity through an instrument known as a hygrometer. We can notice humidity by ourselves, though. Often if it's very humid, our hair may appear wet or damp.
When the air is hot and moisture rises upwards, it condenses and forms clouds. When enough moisture or condensation builds in the clouds, they come down as water, what we know as rain. Sometimes when the air cools on earth, we see air condense as dew. This is best noticed in the morning and on the leaves of plants. The amount of moisture in the air at a given time and place can help us predict the weather.
Next Article: Make a Weather Station: Rain Gauge
