b. Environmental observations are the foundation for understanding the climate system. From the bottom of the ocean to the surface of the Sun, instruments on weather stations, buoys, satellites, and other platforms collect climate data. To learn about past climates, scientists use natural records, such as tree rings, ice cores, and sedimentary layers. Historical observations, such as native knowledge and personal journals, also document past climate change.

This interactive visualization from the NASA Earth Observatory website compares Arctic sea ice minimum extent from 1984 to that of 2012.

In this activity, students review techniques used by scientists as they analyze a 50-year temperature time series dataset. The exercise helps students understand that data typically has considerable variability from year to year and to predict trends, one needs to consider long-term data.

In this activity, students explore how the timing of color change and leaf drop of New England's deciduous trees is changing.

In this intermediate Excel activity, students import US Historical Climate Network mean temperature data into Excel from a station of their choice. They are then guided through the activity on how to use Excel for statistical calculations, graphing, and linear trend estimates. The activity assumes some familiarity with Excel and graphing in Excel.

In this activity students work with real datasets to investigate a real situation regarding disappearing Arctic sea ice. The case study has students working side-by-side with a scientist from the National Snow and Ice Data Center and an Inuit community in Manitoba.

A detailed Google Earth tour of glacier change over the last 50 years introduces this topic in an engaging way. Students are then asked to select from a group of glaciers and create their own Google Earth tour exploring key characteristics and visible changes in that glacier.

This lab exercise is designed to provide a basic understanding of a real-world scientific investigation. Learners are introduced to the concept of tropospheric ozone as an air pollutant due to human activities and burning of fossil fuels. Students analyze and visualize data to investigate this air pollution and climate change problem, determine the season in which it commonly occurs, and communicate the results.

In this role-playing activity, learners are presented with a scenario in which they determine whether the Gulf Stream is responsible for keeping northern Europe warm. They must also address the potential future of the Gulf Stream if polar ice were to continue melting. The students work in small groups to identify the issue, discuss the problem, and develop a problem statement. They are then asked what they need to know to solve the problem.

This activity engages learners to make a model of sediment cores using different kinds of glass beads and sand. They learn how to examine the types, numbers, and conditions of diatom skeletons in the model sediment cores and tell something about the hypothetical paleoclimate that existed when they were deposited. The students get to be climate detectives.