This press release examines recent evidence that the rate of global warming is accelerating, and that in the past twenty-five years it achieved the rate of two degrees Celsius per century, a rate that had been predicted for the twenty-first century. Full description.

In this lab activity students will use cloud cover data from five cities (real data from NASA's TRMM instrument) to prepare a data table and graph using any available software. After downloading the data from the S'COOL homepage, they will prepare a spreadsheet and graph, and write sentences describing the dependent and independent variables and describing each cloud group. The site features text, ... Full description.

This resource provides a network of links related to a wide variety of images, photographs, and other multimedia resources from NASA archives. The site is browsable by subject, NASA Center (Goddard, Johnson, etc.), and by keyword. It also includes links to other NASA images sites. Full description.

In this module, students learn about the physical features, properties, and hazards associated with thunderstorms. Topics include dangers associated with thunderstorms, types and components of thunderstorms, and tornadoes. An additional section discusses the use of computer modeling to understand the formation and lifecycle of storm systems and in forecasting severe weather. Links to additional information ... Full description.

At this site, users can read a basic explanation of the greenhouse effect, which is accompanied by a diagram illustrtating the concept. Links to additional information and to related topics are included. Full description.

Major volcanic eruptions alter the Earth's radiative balance, as volcanic ash and gas clouds absorb terrestrial radiation and scatter a significant amount of the incoming solar radiation, an effect known as "radiative forcing" that can last from two to three years following a volcanic eruption. This results in reduced temperatures in the troposphere, and changes in atmospheric circulation patterns. ... Full description.

This site provides general information on hurricanes, including how they form, where and when conditions favorable to hurricane formation exist, how wind speeds are classified, and what conditions cause hurricanes to diminish and decay. It features text, scientific illusrations, and links to related topics in other parts of the Earth Observatory website. Full description.

This collection of links to EPA information on atmospheric ozone depletion covers topics such as the causes of ozone depletion, possible effects of ultraviolet radiation and how to protect from it, information on chlorofluorocarbons in air conditioning systems and metered dose inhalers, and lists of ozone-depleting substances. Full description.

This database contains imagery from geosationary satellites. Visitors can access daily images or archived imagery form GOES-9, METEOSAT, and other satellites. The imagery features hemispheric and whole-disk views of Earth, water vapor maps, and images of storms and other special events. Links to satellite homepages and to other related topics are included. Full description.

Located in Camp Springs, Maryland, the Volcanic Ash Advisory Center (VAAC) produces volcanic ash advisories and ash forecast and transport models. Real-time ash adivisories, volcano graphics and imagery, and links to related topics are available at the website. Full description.