Why do we experience seasons

Toggle Close. Search calacademy. Search the Educators section. Suggested Unit Progression. Download script. Activity 1: Longer Days, Shorter Nights grades View lesson. Activity 2: Photosynthesis Seen From Space grades Activity 3: Why Do Birds Migrate?

Connections to Standards. A: The Universe and Its Stars Patterns of the apparent motion of the sun, the moon, and stars in the sky can be observed, described, predicted, and explained with models. B: Earth and the Solar System 5 The orbits of Earth around the sun and of the moon around the Earth, together with the rotation of Earth about an axis between its North and South poles, cause observable patterns. These include day and night; daily changes in the length and direction of shadows; and different positions of the sun, moon, and stars at different times of the day, month, and year.

The seasons are a result of that tilt and are caused by the differential intensity of sunlight on different areas of Earth across the year. C: Organization for Matter and Energy Flow in Organisms Plants, algae including phytoplankton , and many microorganisms use the energy from light to make sugars food from carbon dioxide from the atmosphere and water through the process of photosynthesis, which also releases oxygen.

A: Interdependent Relationships in Ecosystems: Organisms, and populations of organisms, are dependent on their environmental interactions both with other living things and with nonliving factors. In this reaction, carbon dioxide and water combine to form carbon-based organic molecules and release oxygen.

Cellular respiration in plants and animals involve chemical reactions with oxygen that release stored energy. In these processes, complex molecules containing carbon react with oxygen to produce carbon dioxide and other materials. California's Environmental Principles and Concepts Principle III: Natural systems proceed through cycles that humans depend upon, benefit from, and can alter.

Concept a: Students need to know that natural systems proceed through cycles and processes that are required for their functioning. Vocabulary for Students. Recommended Resources. Data Sources. More Clips from Habitat Earth. How Did Human Civilization Spread? So, here we are, orbiting the Sun, but tilted a bit and always with the axis pointed in the same direction. Hence, the seasons. It is summer in June in the Northern Hemisphere because the Sun's rays hit that part of Earth more directly than at any other point in Earth's orbit - or, in other words, more directly than at any other time of the year.

It is winter in December in the Northern Hemisphere, because that is when it is the South Pole's turn to be tilted toward the Sun. During the summer, the Sun tracks more directly overhead, rising in the east, overhead at noon, and setting in the west.

If you live in the Southern Hemisphere, the Sun will be more northerly in the sky during the winter that is, June, July, and August. More recently, this thought became fixed to the time of the spring equinox. The underlying assumption relating to standing eggs on end is that there must exist some special gravitational balance. There are many forces acting on an egg when you try to stand it on end on a flat surface.

Some people think that the gravitational pull of the Sun becomes balanced with that of the Earth to allow for this phenomenon to occur. However, the Moon exerts a much stronger gravitational effect on the Earth than the Sun, dominating the ebb and flow of the ocean tides.

The Moon's effects are different at each of the equinoxes however. The most dominant force of gravity on a standing egg is the one between the Earth and the egg itself.

This is determined by the weight of the egg and the force pulling the egg to the counter top. If you want to prove this to yourself, take a fresh, uncooked egg and hold it with the larger end resting on a table or counter top.

Wait for the fluid content of the egg to settle, then carefully test the balance. Be patient as you find the point where you can ever so gently let it go to remain standing on end. Please Contact Us. Please try another search. Multiple locations were found. Please select one of the following:. Location Help. News Headlines. Customize Your Weather. Privacy Policy. Why Do We Have Seasons? Current Hazards. Local Radar. Rivers and Lakes. Climate and Past Weather. Why Do We have Seasons?

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