H
urricanes spin. Floodwaters rise.
Droughts bake the ground. Heat waves and deep freezes grip the planet. What’s up with the weather? It’s not normal. Or is it? It will take time to find answers.
Weather patterns change over a long period of time. So one bad storm may not mean anything. Lots of extreme weather may be a sign that something is changing, though. T at’s why meteorologists are asking questions.
Weather Patterns Meteorologists are weather scientists.
T ey know that weather oſt en follows a pattern. It’s formed by how the sun, ocean, and wind interact. T e sun warms the ocean. T e
warm water evaporates. It becomes vapor. T e vapor rises into the air. Strong winds push the vapor in
diff erent directions. In time, the vapor cools. It turns into rain or snow. It falls to the ground as precipitation. T is is called the water cycle. It helps cause weather patterns. Meteorologists depend on this
pattern to predict the weather. Now, though, it’s getting harder to predict. Here are some examples.
18 NATIONAL GEOGRAPHIC EXPLORER
Warm water evaporates, forming a vapor that rises into the air.
Rising Water One day in May, it began to rain in
a city in the southern United States (U.S.). It oſt en rains in this city in the spring. So no one was surprised. Yet this storm wasn’t normal.
T e rain didn’t stop for two days. Puddles turned into lakes. Creeks became rivers. Water flooded streets and buildings. No one had ever seen anything like it. T is kind of flooding was rare. In
fact, it only happens in this part of the world once in 1,000 years. It wasn’t the only unusual flood.
Soon aſt er, Pakistan flooded. T en part of Australia flooded. T ere, crocodiles swam in the streets!
Water Ways Follow the water cycle.
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