Unit 5: The atmosphere and the Environment

Biofuels like ethanol might help fight climate change. But they can contribute to food insecurity and greenhouse gases in ways that might surprise you.

These two “point-counterpoint” videos provide arguments for and against using nuclear energy to generate electricity.

15 images of various instruments such as rain gauges, wind vanes and weather satellites used to inform us about the weather

What is the nitrogen cycle? How do human activities such as using fertilizer affect the nitrogen cycle? How can this cause greenhouse gases?

5 images of cirrus clouds that are wispy or feather-like clouds at high level, made of ice crystals and may indicate an approaching storm

11 images that illustrate some daily weather conditions such as cold, hot and windy

Temperature is an important part of life on Earth and life in space. This backgrounder explains what temperature is, how it affects people and how it is controlled on the International Space Station.

One-third of all food produced is wasted. Learn about the environmental consequences of food waste, and what you can do about it.

One of the greatest hazards that humans in space face is cosmic radiation. Learn what cosmic radiation is, why it's dangerous, and ways that we are looking at protecting humans in deep space.

How will arctic ice melt from climate change affect exploration, scientific research and geopolitics?

In a few decades, some of the electricity you use might be generated by bacteria.

Did you know that too much carbon dioxide in the classroom can affect your body, and even your grades?

Hydrogen’s tendency towards combustion is what makes it both a dangerous chemical element and a useful energy source.

When a species ends up outside of its natural zone, the consequences on other species, ecosystems and human industries can be severe. Climate change and human activities can introduce species into new zones.

Learn how to make a pH indicator and test water samples.