Topic: Hydrology

20-Year Map of Global Rainfall
This visualization from NASA shows global rainfall patterns over a 22-year span. It incorporates data from a combination of remote-sensing and ground-based sources.

Antarctic Ice Movement: Part I
This video segment adapted from NOVA explains why ice sheets move. To find out how fast they move, scientists carve a tunnel through a glacier.

Antarctic Ice: Sea Level Change
What would happen if a portion of the Antarctic Ice Sheet were to melt? This video segment adapted from NOVA uses animations to show the effect of a 6-meter sea-level rise on coastal cities across the world.

Arctic Sea Ice Satellite Observations
In this interactive activity produced for Teachers' Domain, learn how Arctic sea ice has changed over the past 25 years in terms of maximum winter extent, concentration, and the timing of breakup each spring.

Changing Arctic Landscape
In this video adapted from the Arctic Athabaskan Council, learn how warmer temperatures in the Arctic are transforming the landscape, triggering a host of effects such as permafrost thawing and insect infestations.

Compare the Poles
Explore the defining features of the Arctic and the Antarctic in this interactive activity adapted from the Woods Hole Oceanographic Institution.

The Disappearing Aral Sea
This visualization adapted from NASA features satellite images showing how more than 60 percent of the Aral Sea has disappeared during the last 30 years.

Documenting Glacial Change
This collection of comparative glacier images adapted from the National Snow and Ice Data Center shows substantial changes in five Alaskan glacier positions over periods of 60 to 100 years.

Earth’s Albedo and Global Warming
In this interactive activity adapted from NASA and the U.S. Geological Survey, learn about Earth's albedo (the ratio of reflected vs. incident solar radiation), how pollution alters albedo, and how ice-albedo feedback may accelerate global warming.

Earth's Cryosphere: The Arctic
In this video segment adapted from NASA, take a tour of the cryosphere in North America and the Arctic using satellite imagery.

Earth System: El Niño
This video segment adapted from NASA's Goddard Space Flight Center describes El Niño, how it forms, and the chain reaction of consequences it triggers around the globe.

Fastest Glacier
In this video segment adapted from NOVA scienceNOW, scientists in western Greenland explain how a glacier there is shrinking and moving faster due to increased melting.

Glaciers
Featuring images of glacier formations, this interactive resource adapted from the National Park Service explains what glaciers are, where they are found, how they form, and how they move.

The Grand Canyon: Conservation and Development
This video segment adapted from NOVA explores the effects of the Glen Canyon Dam on the beaches, wildlife, and vegetation of the Colorado River.

Hoover Dam and Hydroelectric Power
How does a dam generate electricity and what are the environmental impacts of operating these mammoth structures? Find out in this video segment adapted from Building Big.

How Do Avalanches Form?
In this video segment adapted from NOVA, dramatic footage of avalanches and animations of ice crystals illustrate how a layer of weakly-bonded snow can contribute to a devastating avalanche.

Hurricanes: New Orleans Under Threat
This video segment adapted from NOVA scienceNOW exposes how decades of development and geography combined to make the potential damage from a hurricane uniquely devastating in New Orleans, Louisiana.

The Mississippi River Delta
These images from NASA, the Lunar and Planetary Institute, and U.S. Geological Survey illustrate the effects of severe storms and decades of river management on the size and shape of the Louisiana coastline and the Mississippi River Delta.

Observations of Climate Change
In this media-rich activity, students learn how data gathered through surveys with local residents and data collected by remote satellites are complementary tools that help deepen our understanding of the effects of climate change in the Arctic and elsewhere.

Sound Waves Underwater: The Loch Ness Monster
This video segment, adapted from NOVA follows a team of enthusiasts and scientists who attempt to find a trace of the Loch Ness monster by scouring the lake with sonar.

Water Conservation: Denver, CO
This video segment adapted from Last Oasis explores the use of new dams as a way to provide or store water. In the 1990s, the city of Denver was looking for a new source of water for its growing population, and its plan to build a new dam suddenly became highly controversial.

Water Conservation: Mexico
This video segment adapted from Last Oasis shows the challenges Mexico City faces in providing enough water for its growing population. As a result of over pumping of its ground water, some parts of the city are sinking 12 inches a year.