Climate Change
Drought, heat, and demand for irrigation have been shrinking Iran’s salty Lake Urmia over the past few decades.
USGS and NASA
Climate is the long-term pattern of weather in a particular area. Weather can change from hour to hour, day to day, month to month or even from year to year. For periods of 30 years or more, however, distinct weather patterns occur. A desert might experience a rainy week, but over the long term, the region receives very little rainfall. It has a dry climate.
Global warming is often linked to the burning of fossil fuels—coal, oil, and natural gas—by industries and cars. Warming is also linked to the destruction of tropical forests. Such human activity has increased the amount of carbon dioxide in the atmosphere by more than 20 percent in the past 100 years.
The climate has changed many times during Earth’s history, but the changes have occurred slowly, over thousands of years. Only in the past several centuries have human activities begun to influence climate—and scientists are still struggling to understand what the consequences will be.
Classroom Activities
Climate change is a complex and multi-faceted issue, with global and local implications. Let us help you tackle it in the classroom with activities designed to make it both relevant and understandable for students across grade levels.
Find even more climate change-related activities here.
Mapping Climate Change
Head over to MapMaker Interactive to create your own visualizations of climate change using our pre-formatted layers. Get started with the "Human Footprint" layer, and dive deeper with "Alternative Energy Use," "Climate Zones," and "CO2 Emissions."
Climate Change in the News
Encyclopedia: Climate Change
Climate change is a long-term shift in global or regional climate patterns. Often climate change refers specifically to the rise in global temperatures from the mid 20th century to present.