NASA
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A new study by NASA scientist Joey Comiso has found that the oldest and thickest Arctic sea ice is disappearing at a faster rate than the younger and thinner ice at the edges of the ice cap. The rapid disappearance of older ice makes the Arctic Ocean's sea ice cap more vulnerable to further decline. Arctic multi-year ice “extent”—which includes all areas where at least 15 percent of the ocean surface is covered by multi-year ice—has been vanishing at a rate of –15.1 percent per decade, Comiso found. Over the same period, the “area” covered by multi-year ice—which discards open water among ice floes and focuses exclusively on regions that are completely covered—has been shrinking by –17.2 percent per decade.
Oldest Arctic Sea Ice is Disappearing : Image of the Day
Southeastern USA at Night : Image of the Day
The southern United States is known for its distinctive cultural and historical identity within the country, including distinct music, cuisine, literature, and social customs. The U.S. Census Bureau defines “The South” as including the states of Alabama, Arkansas, Delaware, Florida, Georgia, Kentucky, Louisiana, Maryland, Mississippi, North Carolina, Oklahoma, South Carolina, Tennessee, Texas, Virginia, and West Virginia. This astronaut photograph from the International Space Station highlights the southeastern part of the South at night, including the eastern Gulf of Mexico and lower Atlantic Seaboard states. The view is part of a time-lapse series of images that extends from just southwest of Mexico to northeast of Newfoundland, Canada. New sequences from the Space Station are regularly posted on the Crew Earth Observation videos page.
A new satellite instrument is sending back detailed information about the health of Earth's ozone layer, the atmospheric gas that shields life from harmful levels of the Sun's ultraviolet radiation. The Ozone Mapper and Profiler Suite, or OMPS—one of five new instruments on the Suomi National Polar-orbiting Partnership (NPP) satellite—will add to a record of space-based ozone monitoring that dates back to 1978. The images above show the concentration of ozone in Earth's atmosphere above the South Pole on January 27, 2012. Measurements are expressed in Dobson Units, the number of molecules required to create a layer of pure ozone 0.01 millimeters thick at a temperature of 0 degrees Celsius and a pressure of 1 atmosphere (the air pressure at the surface of the Earth). The ozone layer’s average thickness is about 300 Dobson Units, a layer that is 3 millimeters thick, or the height of two U.S. pennies stacked together.
Extending the Ozone Monitoring Record : Image of the Day
A clearly visible line marks about 50 kilometers of the international border between Egypt and Israel in this astronaut photograph. The area shown lies between 10 to 60 kilometers (from left to right) from the Mediterranean Sea, which is beyond this image to the northwest. This image from the International Space Station shows the characteristic sand dune morphology of the region and the poor soils which mark the southern limit of agriculture. The different colors of the land surface are the result of trampling by humans and their livestock. Trampling disturbs the dark-colored soil crusts on the Egyptian side of the border, allowing lighter-colored dune sand beneath the crusts to be exposed by winds. A road also follows the border, making the demarcation more prominent.
Israel-Egypt-Gaza border region : Image of the Day
Suguta Valley, Kenya : Image of the Day
The Suguta Valley is one of the driest places in Kenya, and may be one of the driest places near Earth's Equator. The remote location limits field studies, but data indicate that annual precipitation is less than 300 millimeters (12 inches) a year, while evaporation ranges from 3,000 to 4,000 millimeters (120 to 160 inches). And yet, as recently as 8,000 years ago, this arid valley was a vast lake.
Polynyas and the Pine Island Glacier, Antarctica : Image of the Day
Though far distant from any permanent settlement, Antarctica is poised to impact human life around the globe. Sea levels are rising in part because land-based ice is melting. Rising sea levels increase coastal erosion and flooding. And one of the largest single contributors to sea level rise in recent years is Antarctica’s Pine Island Glacier. Shrinking at a rate of 100 meters (300 feet) per year, the Pine Island Glacier is responsible for seven percent of the world’s recent sea level rise. Why is the Pine Island Glacier melting so quickly?
Nyamuragira Volcano Erupts : Image of the Day
On November 6, 2011, after more than a year of relative peace, the Nyamuragira volcano in the Democratic Republic of Congo surged to life. Lava has erupted spectacularly from a fissure low on one of the volcano's flanks and spilled northward, away from populated areas. Nyamuragira is a shield volcano and one of Africa's most active. For more than a week, cloud cover mostly obscured the view from space until the Advanced Land Imager on NASA’s EO-1 satellite captured images on November 12, 2011.
In the summer of 1988, lightning- and human-ignited fires consumed vast stretches of Yellowstone National Park. More than 25,000 firefighters cycled through the park combating 50 wildfires, seven of which became major wildfires. By the time the first snowfall extinguished the last flames in September, 793,000 of the park’s 2,221,800 acres had burned.
World of Change: Burn Recovery in Yellowstone : Feature Articles
On a sunny spring day in November 2011, the clouds parted over coastal Argentina to reveal a massive bloom of phytoplankton coloring the ocean. Phytoplankton are microscopic, plant-like organisms that harness sunlight to turn carbon dioxide and water into sugars and oxygen (photosynthesis). They are the primary producers of the ocean and the center of the marine food web, providing food for everything from zooplankton to whales. The Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Aqua satellite captured this natural-color image on November 5, 2011.
Blooming Waters off Argentina : Image of the Day
A massive cloudbank sprawled over central Europe in early November 2011, with clouds extending from the North Sea to the foothills of the Alps. Over the crescent-shaped mountain range, skies remained clear. The Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra satellite acquired this natural-color image on November 10. Along the southern margin of the cloud bank, Alpine foothills predominate. Only the valleys hold the low-elevation clouds, or fog, and surrounding hillsides rise above it.
Low Clouds over Central Europe : Image of the Day
Re-entry of Progress Spacecraft 42P : Image of the Day
Have you ever wondered how the astronauts and cosmonauts onboard the International Space Station (ISS) take out the trash? Several times a year, robotic spacecraft carrying a variety of items—including food, water, fuel, oxygen, medical supplies, replacement parts, and research materials—are launched from Earth to dock with the ISS. These spacecraft are built and launched by ISS international partners in Russia, Japan, and the Europe . After the cargo has been transferred to the ISS, the spacecraft is refilled with refuse, and then undocked and de-orbited—essentially using the Earth’s atmosphere as an incinerator for both the spent spacecraft and the refuse. This astronaut photograph highlights the reentry plasma trail of one such spacecraft, the ISS Progress 42P supply vehicle (Russian designation M-10M). The Progress is based on the Soyuz design, and can fly autonomously or under remote control from the space station.Since it began in 1983, the eruption of Kilauea Volcano has usually been centered at Pu’u ’O’o. Gray and brown lava flows radiate from the crater, with the varying shades due to differences in weathering, composition, and the lava’s initial temperature. Photographs of Pu’u ’O’o from the U.S. Geological Survey reveal the remarkable variety of colors and textures in the lava. The overlapping flows form a record of the evolving eruption. The extent of change since early September 2011 is remarkable.
Fresh Lava Flows Surround Pu'u 'O'o : Image of the Day
Eleven days after its launch into Earth orbit, the new satellite known as NPP sent back its first science data on November 8, 2011, part of a series of instrument startups and checkouts that will take place before the satellite goes into full operational mode. The National Polar-orbiting Operational Environmental Satellite System Preparatory Project (NPP) carries five instruments that will improve day-to-day weather forecasting while extending the record of many long-term observations of Earth's climate. This image from the Advanced Technology Microwave Sounder (ATMS) depicts the location and abundance of water vapor in the lower atmosphere, from the surface to 5 kilometers altitude.
First Light for NPP : Image of the Day
Powerful Storm hits Alaska : Image of the Day
A rare, extremely powerful winter storm hit northwestern Alaska on November 8 and 9, 2011, bringing hurricane-force winds, high seas, and heavy snow. Nome, the largest community affected by the storm, was buffeted by winds gusting to 66 miles per hour and a 10-foot storm surge. The National Weather Service reported wind gusts up to 85 miles per hour in Wales, northwest of Nome. Coastal flood warnings were still in effect throughout northwest Alaska on November 10. The storm was like a hurricane in many ways. The air pressure dropped to 945 millibars, comparable to a Category 3 hurricane.Greenland’s Jakobshavn glacier has the potential to influence sea level rise more than any other single feature in the Northern Hemisphere. Like a funnel, the large glacier channels ice from much of the Greenland ice sheet into the Atlantic Ocean, at a rate of about 15 kilometers per year. It is the world’s fastest flowing glacier. Why do some glaciers, like Jakobshavn, feed ice into the ocean so quickly while others barely move at all? Answering that question is crucial because if we are to predict how much sea levels will rise as Earth warms, we have to know how much ice glaciers will deliver to the ocean. The key to predicting glacier flow is to map the ground beneath the ice—a concept described in the Earth Observatory’s new feature, IceBridge: Building a record of Earth’s changing ice, one flight at a time.