7.ESS3.2 - Engage in a scientific argument through graphing and translating data regarding human activity and climate.

Ice Age - time in Earth's history during which glaciers covered large parts of the surface.

Aerosols - solid particles or liquid droplets in the atmosphere.

Sunspot - a dark area of gas on the sun's surface that is cooler than surrounding gases.

Greenhouse gases - gases in the atmosphere that trap energy.

Fossil fuels - energy-rich substances formed from the remains of organisms.

Global Warming - a gradual increase in the average temperature of the atmosphere, thought to be caused by an increase in greenhouse gases from human activities.

In studying ancient climates, scientists follow n important principle: If plants and animals today need certain conditions to live, then similar plants and animals in the past also required those conditions. Possible explanations for major climate changes include movement of continents, variations in the position of Earth relative to the sun, major volcanic eruptions, and changes in the sun's energy output. Many human activities are increasing the level of greenhouse gases in the atmosphere, causing global temperatures to rise. The effects of global warming include melting glaciers, rising sea levels, drought, desertification, changes in the biosphere, and regional changes in temperature. Solutions for limiting global warming include finding clean, renewable sources of energy, being more energy efficient, and removing carbon from fossil fuel emissions.