Rio de Janeiro

Published April 14, 2002

A dengue fever outbreak has plagued Rio de Janeiro since January 2002. Dengue fever is a mosquito-borne disease. The elimination of standing water, which is a breeding ground for the mosquitoes, is a primary defense against mosquito-borne diseases like dengue. Removing such water remains a difficult problem in many urban regions.

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Ash and Steam, Soufriere Hills Volcano, Monserrat

Published April 7, 2002

International Space Station crew members are regularly alerted to dynamic events on the Earth’s surface. On request from scientists on the ground, the ISS crew observed and recorded volcanic activity from the summit of Soufriere Hills on March 20, 2002.

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Glacial Retreat in Chilean Patagonia

Published March 31, 2002

The San Quintín Glacier is the largest outflow glacier of the Northern Patagonian Ice Field in southern Chile. Like many glaciers worldwide during the twentieth century, San Quintín appears to be losing mass and possibly retreating.

Image Transformations-Montserrat

Published March 27, 2002

An Earth Observatory reader used widely available software to correct the oblique perspective of an earlier photograph of Montserrat and to adjust the color. The story of how he modified the image includes step-by-step instructions that can be applied to other photographs.

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Kiritimati, Kiribati (Christmas Island)

Published March 24, 2002

Pronounced “Ki-ris-mas,” Kiritimati Island has a large in-filled lagoon that gives it the largest land area (125 square miles, 321 square kilometers) of any atoll in the world. Captain Cook named the atoll Christmas Island when he arrived on Christmas Eve in 1777. Used for nuclear testing in the 1950s and 1960s, the island is now valued for its marine and wildlife resources. It is particularly important as a seabird nesting site—with an estimated 6 million birds using or breeding on the island, including several million Sooty Terns. Rainfall on Kiritimati is linked to El Ni&ntidle;o patterns, with long droughts experienced between the wetter El Ni&ntidle;o years.

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Tsunami Vulnerability in Camana, Peru

Published March 17, 2002

A tsunami washed over the low-lying coastal resort region near Camaná,southern Peru, following a strong earthquake on June 23, 2001. The earthquake was one of the most powerful of the last 35 years and had a magnitude of 8.4. After the initial quake, coastal residents witnessed a sudden draw-down of the ocean and knew a tsunami was imminent. They had less than 20 minutes to reach higher ground before the tsunami hit. Waves as high as 8 meters came in four destructive surges reaching as far as 1.2 kilometers inland. Thousands of buildings were destroyed, and the combined earthquake and tsunami killed as many as 139 people.

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Shiveluch—Kamchatkan volcanoes

Published March 10, 2002

Shiveluch volcano anchors the northern end of a volcanic chain of more than 100 volcanoes covering the Kamchatkan Peninsula. It is one of the most active volcanoes along the Pacific Rim. In 2001, astronauts aboard the International Space Station Alpha looked north toward Shiveluch’s scarred southern slope to get a unique perspective of the impressive cluster of volcanoes in the Klyuchevskaya group and Shiveluch.

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Mesopotamian Marshes

Published March 3, 2002

The Al Hawizah Marshes comprise the largest remaining tract of wetlands in the Mesopotamian Marshlands of Iran and Iraq. In the last 10 years, damming and diversion of waters from the Tigris and Euphrates Rivers, and draining of wetlands has led to a loss of 85% of wetlands that once covered about 20,000 square km (7,725 square miles).

Santa Maria Volcano, Guatemala

Published February 24, 2002

The eruption of Santa Maria volcano in 1902 was one of the largest eruptions of the 20^th century, forming a large crater on the mountain’s southwest flank. Since 1922, a lava-dome complex, Santiaguito, has been forming in the 1902 crater. Growth of the dome has produced pyroclastic flows as recently as the 2001—they can be identified in this image. The volcano is considered dangerous because of the possibility of a dome collapse such as one that occurred in 1929, which killed about 5000 people. A second hazard results from the flow of volcanic debris into rivers south of Santiaguito, which can lead tocatastrophic flooding and mud flows.

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Anti-Atlas Mountains, Morocco

Published February 10, 2002

The Anti-Atlas Mountains of northern Africa and the nearby Atlas mountains were created by the prolonged collision of the African and Eurasian tectonic plates, beginning about 80 million years ago.

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Northern Patagonian Ice Field, Chile

Published February 2, 2002

The Northern Patagonian Ice Field (NPIF), centered near 47°S, 73.5°W, is the smaller of two remnant ice masses crowning the Andes Mountains of lower South America. The NPIF is a vestige of an extensive ice sheet that covered much of Patagonia just over a million years ago. Today, with its glaciers largely in retreat and only an area of 4,200 sq km, it is still the largest continuous mass of ice outside of the polar regions.

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Shrimp Farms and Mangroves, Gulf of Fonseca

Published January 27, 2002

For decades, astronauts on space missions have documented land use changes around the world. Here, astronauts track the development of shrimp farming along the Honduran coastline of the Gulf of Fonseca between 1989 and 2001.

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