Chapter 1 what is a season In many parts of the world people swim in lakes during summer And they ice skate on those same lakes during winter But they cannot ice skate in the summer and they would not want to swim in the winter Why is the weather so different during summer and winter The same lakes people skate on in the winter turn to liquid water in the summer all thanks to Earth's cycles What is a cycle
These changes happen because of Earth's seasonal cycle The natural world has many different cycles A cycle is a pattern that repeats over time in a predictable way A boy jumps into a lake on a hot summer day
Measuring the Seasons What is a season We think of summer as warm and winter as cold But suppose there is a warm day in winter That does not mean it is summer The seasons begin and end on specific dates These dates are based on the position of the sun and Earth This is the astronomical definition of seasons It takes 365 24 days or about one year for Earth to make one trip around the sun 6
But not everyone measures the seasons in this way Meteorologists are scientists who study the weather They base seasons on the temperature at different times of year This system does not depend on the sun's position It depends more on the climate or long term weather patterns A METEOROLOGIST TAKES A READING OF WEATHER SENSING EQUIPMENT
