In the mid-1980s, the winter sea ice pack in the Arctic was dominated by multi-year ice—ice that had survived at least one summer melt. Today, less than half of the sea ice at winter maximum has survived at least one summer.

An expert on climate conditions in East Africa describes the climate factors behind the 2011 drought, which has contributed to food insecurity and famine.

Near the Earth’s equator, solar heating is intense year round. Converging trade winds and abundant water vapor all combine to produce a persistent belt of daily showers known as the Intertropical Convergence Zone.

The ocean is the largest solar energy collector on Earth. More than 90 percent of the warming that has happened on Earth over the past 50 years has occurred in the ocean. Not all of that heating is detectable at the surface because currents move some of the heat to deeper layers of water, where it can "hide" for years or decades.

We can have record-setting blizzards and global warming at the same time. NOAA scientists explain climate variability, how it influenced our weather this winter, and how it differs from climate change.

In this activity students work with data to analyze local and global temperature anomaly data to look for warming trends. The activity focuses on the Great Lakes area.

This collection of photos from the NASA Climate website features images related to global change. Not all images show change caused directly by climate change and energy use, and descriptive captions indicate causes for change in most of the images.

In this activity students learn how Earth's energy balance is regulating climate. This activity is lesson 4 in the nine-lesson module Visualizing and Understanding the Science of Climate Change.

This webinar will examine how variations in the tropical Pacific can affect high-latitude regions such as Alaska.