This is an interactive graph that involves records of ice cover in two Wisconsin lakes - Lake Mendota and Lake Monona - from 1855-2010.

This short video illustrates the phenomena of El NiÃo and La NiÃa: their relationships to tradewinds and surface water temperatures, and their effects on precipitation in North America.

This animation illustrates how the hardiness zones for plants have changed between 1990 and 2006 based data from 5,000 National Climatic Data Center cooperative stations across the continental United States.

This multi-part activity introduces users to normal seasonal sea surface temperature (SST) variation as well as extreme variation, as in the case of El NiÃo and La NiÃa events, in the equatorial Pacific Ocean. Via a THREDDS server, users learn how to download seasonal SST data for the years 1982 to 1998. Using a geographic information system (GIS), they visualize and analyze that data, looking for the tell-tale SST signature of El NiÃo and La NiÃa events that occurred during that time period. At the end, students analyze a season of their own choosing to determine if an El NiÃo or La NiÃa SST pattern emerged in that year's data.

This NOAA visualization on YouTube shows the seasonal variations in sea surface temperatures and ice cover from 1985 to 2007. The visualization is based on data collected by NOAA polar-orbiting satellites. El NiÃo and La NiÃa are easily identified, as are the trends in decreasing polar sea ice.

This lesson explores El NiÃo by looking at sea surface temperature, sea surface height, and wind vectors in order to seek out any correlations there may be among these three variables using the My NASA Data Live Access Server. The lesson guides the students through data representing the strong El NiÃo from 1997 to 1998. In this way, students will model the methods of researchers who bring their expertise to study integrated science questions.

This is a sequence of 5 classroom activities focusing on the El NiÃo climate variability. The activities increase in complexity and student-directedness. The focus of the activities is on accessing and manipulating real data to help students understand El NiÃo as an interaction of Earth systems.

In this activity, students analyze data maps of sea surface temperature anomalies for a 14-year interval and create an ENSO time line in a case study format. Based on their findings, students determine the recurrence interval of the ENSO system.

In this activity, students are introduced to tree rings by examining a cross section of a tree, also known as a 'tree cookie.' They discover how tree age can be determined by studying the rings and how ring thickness can be used to deduce times of optimal growing conditions. Next, they investigate simulated tree rings applying the scientific method to explore how climatic conditions varied over time.

In this activity, students work with climate data from the tropical Pacific Ocean to understand how sea-surface temperature and atmospheric pressure affect precipitation in the tropical Pacific in a case study format.