A long time ago when people lived mostly out-of-doors, they were close to nature. They noticed that plants, mammals, insects, and birds sensed the coming of storm sooner than people did. All living things have a natural instinct to save their own lives, and so they look for shelter just before a storm. When ancient people saw animals seeking shelter, they did, too.
Of course, plants and animals do not actually forecast weather, but they are good weather indicators. The elements that make up weather-atmospheric pressure, moisture, temperature, and wind-affect living things in special ways, and their reactions give clues to weather changes. The people of long ago called these clues “weather sings”, and those who knew how to read the sings were often just as correct in their predictions as modern meteorologists, the scientists who study weather and collect weather information with complicated scientific instruments.
Meteorologists tell us that during fair weather the air usually contains very little moisture. But just before a rain the air becomes damp and has a higher relative humidity. Humidity is the amount of moisture in the air compared to how much it could hold. When the air has all the moisture it can hold, it is saturated. You might compare it to a sponge. When a sponge is damp it is wet, but has relatively little moisture in it. When it is dropping wet, it is saturated.
Now meteorologists use special instruments to measure relative humidity, but in earlier times, people relied on nature to tell them when the humidity was high. Spiders were one of their best humidity indicators.
Normally, spiders spin their webs between 6 and 7 p. m. During calm, clear weather they don’t bother to make large webs or to take in. But when there is high humidity and a drop in air pressure spiders work overtime building more and larger dragnets. Somehow they seem to know that insects will be easier to catch when the humidity is high. The moisture in the air soaks the insects “wings, making it difficult for them to fly. However, since a heavy rain would ruin the net and wash away the bugs caught in it, spiders will take down their nets before a storm. An old saying warns:
When spiders take in their net,
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Frogs and toads come out and feast on the easily caught insects when the air is cool and moist. Toads seldom come out when the air is dry. This is also true of frogs, and it is another reason why you can hear more of them before a rain.
III. Answer the questions:
1. Why were people in old times closer to nature?
2. Who sence the coming of storm sooner?
3. What do usually anomals, birds and insects look for before a storm?
4. What elements make up weather?
5. When do the spiders spin large werbs?
6. Why do they spin large werbs before a storm?
7. What other weather sings’ do you know? (give an example).