Background Lessons for Journey North Global Climates and Seasons Temperature (Back to Lesson >>) What Scientists Think Did you notice that temperatures seem to get cooler as you go north or south from the equator? Did the temperature bands seem to move north in the first half of the year and south in the second half of the year? Here's why: Because the earth is tilted on its axis, the sun heats it unevenly. Areas closest to the equator (tropical and subtropical zones) get more direct sunlight all year. They are the hottest zones. Areas farther from the equator (temperate and polar zones) get less direct sunlight, and the number of hours of sunlight per day changes a great deal throughout the year.) They are colder regions. During our summer, the Northern Hemisphere leans toward the sun in its revolution. There are more daylight hours, and the sun’s angle is more direct than at other times of year. So it's warmer. The opposite happens in the winter when we are tilted away from the sun. Its rays are slanted (less intense) and we have fewer daylight hours. As we move from summer to fall and winter (as the earth revolves and is eventually tipped away), days get shorter and the temperatures get cooler. The opposite happens from winter to summer. But the Southern Hemisphere is tilted away from the sun when we are tilted toward it. So they have opposite seasons and temperature patterns. That's why the temperature lines on the map seem to move north and south with the seasons. These global temperature differences cause our different climates (including factors such as winds, humidity, and precipitation)! Journaling Questions How do you think temperature changes over the course of a year affect the animal you're studying and its migration? How do they affect your animal's ability to meet its basic needs? Do you think everyone throughout the United States and Canada experiences four seasons? If you have friends and family in other parts of the country, ask about their seasons. How different is each one? Once you've thought about this, read the box below. Seasons in the United States and Canada? Seasons are often defined as the major divisions of the year that are based on temperature and/or precipitation changes. In parts of the South, the average temperatures may only change from 75 degrees in the winter to 90 degrees in the summer. But to someone from the Midwest, where average temperatures could range from -20 in the winter to 80 in the summer, the Southern seasons hardly count! In general, places farther to the south and closer to water have smaller seasonal variations. It's a matter of opinion and just might depend on how you define "seasons." Related Links See a climate zone chart >> Also learn about Global Precipitation >> Back to Lesson >> Facebook Pinterest Twitter © 1997 – 2019 Journey North. All rights reserved.