c. Climate change is a significant and persistent change in an area's average climate conditions or their extremes. Seasonal variations and multi-year cycles (for example, the El Niño Southern Oscillation) that produce warm, cool, wet, or dry periods across different regions are a natural part of climate variability. They do not represent climate change.

This lesson sequence guides students to learn about the geography and the unique characteristics of the Arctic, including vegetation, and people who live there. Students use Google Earth to explore the Arctic and learn about meteorological observations in the Arctic, including collecting their own data in hands-on experiments. This is the first part of a three-part curriculum about Arctic climate.

This video reviews how increasing temperatures in the Arctic are affecting the path of the jet stream, the severity of storms, and the length of individual weather events (rain, storms, drought).

In this jigsaw activity, students explore meteorological data collected from Eureka, Canada to try to decide when would be the best time for an Arctic visit.

This activity introduces students to stratigraphic correlation and the dating of geologic materials, using coastal sediment cores that preserve a record of past hurricane activity.

The activity takes a hands-on approach to understanding El NiÃo by physically showing and feeling the process. It consists of an El NiÃo demo to be performed by the teacher and observed by the class as well as an experiment to be conducted by the students themselves individually or in pairs to illustrate the connection between water temperature and atmospheric temperature. Students are asked to make conclusions based on their findings and then examine the chain of events stemming from El NiÃo.

This video shows 15 years of data obtained via Polar-orbiting satellites that are able to detect subtle differences in ocean color, allowing scientists to see where there are higher concentrations of phytoplankton - a proxy for the concentration of chlorophyll in the ocean.

This National Geographic video explains the origins of the El NiÃo Southern Oscillation using animations and shows the impacts on humans, wildlife and habitat, particularly in the United States.

This video describes the impact of extreme heat on Philadelphia in the summer of 2011 and how the city is adapting to new expectations about its weather. It uses this example to introduce the new national climate normals, released by NOAA's National Climatic Data Center (NCDC) that summer.

In this lesson, students examine and interpret varied observational datasets and are asked to determine whether the data supports or does not support the statement: climate change is occurring in Colorado.