ISS016-E-21564
The garden—recognizable by its light green color relative to the surrounding built materials—was originally commissioned by Catherine de Medici in 1559, and is now bounded by the Place de la Concorde to the northeast and the Louvre museum along the Seine River at the southeast end. Other, similarly colored parks and greenspaces are visible throughout the image. Farther south on the Seine is the Íle de la Cité, location of the famous Notre Dame cathedral. Perhaps most prominent is the characteristic “A” profile of the Eiffel Tower west of the Jardin des Tuileries, highlighted by morning sunlight.
ISS016-E-23196
Gray linear patches at the bottom of the image are thin clouds. Blue patches and streaks on the iceberg are melt ponds. The existence of melt ponds, combined with high summer temperatures, suggest to glaciologists that this iceberg is fast approaching the point of breaking up, probably within a few months. Ted Scambos, glaciologist and Lead Scientist at the National Snow and Ice Data Center, comments, “This is an iceberg worth watching, because, being water-saturated, it may well show a sudden, crumbling, disintegration, spreading fine blue micro-icebergs over the ocean surface.”
The top image of mega-iceberg A53a was created by stitching together two individual astronaut photos. The lower image shows A53a in the process of breaking off from the Larsen Ice Shelf in late 2004. The wider view of the ice shelf is based on the MODIS Mosaic of Antarctica image map. Some features acquired during the iceberg’s calving have been maintained in the years since.
Icebergs of the southern Atlantic Ocean contain rock material from Antarctica, eroded by the moving ice, and also wind-borne dust from deserts in Africa, South America, and Australia. The finest powdery rock material acts as nutrients for sea organisms. As the sediment-laden icebergs melt, they enrich the surrounding seawater with minerals. The area of enrichment is significantly larger when a mega-iceberg disintegrates into many small pieces.
Because of the capacity to take high-resolution photos at oblique angles through gaps in cloud cover, astronaut photography from the ISS is a unique resource for documenting the break up of major icebergs. As part of NASA’s International Polar Year activities, images of A53a and other large icebergs are being acquired from the ISS to support a study of massive icebergs.
The study is aimed at understanding the way entire ice shelves—such as those that surround Antarctica today—evolve as climate changes. When large masses of ice float into warmer waters north of their usual latitudes, they undergo change at rapidly increased rates. Changes that would take decades to occur in Antarctica can happen in a few years or even months at latitudes near 50 degrees south. Observing these changes in mega-icebergs can educate scientists about the process of ice shelf breakup.
Astronauts have observed other major icebergs in the South Atlantic Ocean, for example, the berg identified as A22a.
ISS016-E-23197
Gray linear patches at the bottom of the image are thin clouds. Blue patches and streaks on the iceberg are melt ponds. The existence of melt ponds, combined with high summer temperatures, suggest to glaciologists that this iceberg is fast approaching the point of breaking up, probably within a few months. Ted Scambos, glaciologist and Lead Scientist at the National Snow and Ice Data Center, comments, “This is an iceberg worth watching, because, being water-saturated, it may well show a sudden, crumbling, disintegration, spreading fine blue micro-icebergs over the ocean surface.”
The top image of mega-iceberg A53a was created by stitching together two individual astronaut photos. The lower image shows A53a in the process of breaking off from the Larsen Ice Shelf in late 2004. The wider view of the ice shelf is based on the MODIS Mosaic of Antarctica image map. Some features acquired during the iceberg’s calving have been maintained in the years since.
Icebergs of the southern Atlantic Ocean contain rock material from Antarctica, eroded by the moving ice, and also wind-borne dust from deserts in Africa, South America, and Australia. The finest powdery rock material acts as nutrients for sea organisms. As the sediment-laden icebergs melt, they enrich the surrounding seawater with minerals. The area of enrichment is significantly larger when a mega-iceberg disintegrates into many small pieces.
Because of the capacity to take high-resolution photos at oblique angles through gaps in cloud cover, astronaut photography from the ISS is a unique resource for documenting the break up of major icebergs. As part of NASA’s International Polar Year activities, images of A53a and other large icebergs are being acquired from the ISS to support a study of massive icebergs.
The study is aimed at understanding the way entire ice shelves—such as those that surround Antarctica today—evolve as climate changes. When large masses of ice float into warmer waters north of their usual latitudes, they undergo change at rapidly increased rates. Changes that would take decades to occur in Antarctica can happen in a few years or even months at latitudes near 50 degrees south. Observing these changes in mega-icebergs can educate scientists about the process of ice shelf breakup.
Astronauts have observed other major icebergs in the South Atlantic Ocean, for example, the berg identified as A22a.
ISS016-E-18493
Originally known simply as “Amboy,” “Perth” was added to the name in honor of the Earl of Perth when the city became the capital of East Jersey in 1686. Together with South Amboy across the Raritan River, both cities are collectively known today as “the Amboys.” Perth Amboy is currently undergoing urban renewal and redevelopment to resume its former status as a resort destination. Raritan Bay also provides a source of local income through clam fishing. However, the unwillingness of clams to observe the political border between Staten Island (New York) and New Jersey has led to occasional friction between both states’ clammers.
ISS016-E-27426
As water in the rising air mass condenses and changes from a gas to a liquid state, it releases energy to its surroundings, further heating the surrounding air and leading to more convection and rising of the cloud mass to higher altitudes. This leads to the characteristic vertical “towers” associated with cumulonimbus clouds, an excellent example of which is visible in this astronaut photograph. If enough moisture is present to condense and heat the cloud mass through several convective cycles, a tower can rise to altitudes of approximately 10 kilometers at high latitudes and to 20 kilometers in the tropics before encountering a region of the atmosphere known as the tropopause—the boundary between the troposphere and the stratosphere.
The tropopause is characterized by a strong temperature inversion. Beyond the tropopause, the air no longer gets colder as altitude increases. The tropopause halts further upward motion of the cloud mass. The cloud tops flatten and spread into an anvil shape, as illustrated by this astronaut photograph. The photo was taken from a viewpoint that was at an angle from the vertical, rather than looking straight down towards the Earth’s surface. The image, taken while the International Space Station was located over western Africa near the Senegal-Mali border, shows a fully formed anvil cloud with numerous smaller cumulonimbus towers rising near it. The high energy levels of these storm systems typically make them hazardous due to associated heavy precipitation, lightning, high wind speeds and possible tornadoes.
ISS016-E-30337
The town of Avezzano (top right), near the drainage outlet of the basin, lies 80 kilometers east of Rome. The “circumference road” runs around the edge of the former lake; it roughly follows the boundary between green, vegetated fields around the basin and tan fallow fields within. This recent astronaut photograph shows a dusting of snow along mountain ridges to the south (upper and lower left).
The basin of Fucine Lake has no natural outlet. Consequently the level of the original lake fluctuated widely with any higher-than-average rainfall. In Roman times, this variability caused flooding of the fishing communities around the lake. (Some of these towns, with their distinctive red tile roofs, are located around the margin of the lake floor.) Emperors Claudius and Hadrian achieved limited draining of the original lake—to control both flooding and malaria—by digging and then expanding a tunnel through the hills near Avezzano at the top of the image. Claudius used 30,000 workers over a span of ten years to dig the 5.6-kilometer-long tunnel. This engineering work reduced the size of the lake from an original area of about 140 square kilometers to about 57 square kilometers.
After the Roman Empire collapsed and maintenance failed, the tunnel was blocked up with vegetation and sediment. An earthquake—possibly the same event that damaged the Coliseum, somewhat before 508 CE—dropped the lake bottom by 30-35 centimeters. Drainage slowed, and the lake expanded; water filled the basin for the next 1,000 years. A serious draining effort was commissioned by Prince Alessandro Torlonia in 1862. That effort achieved complete emptying of the lake, giving it the modern appearance.
ISS016-E-19394
The Al Wadj Bank (a bank is an underwater hill) includes a healthy and diverse reef system, extensive seagrass beds, and perhaps the largest population of dugong—a marine mammal similar to the North American manatee—in the eastern Red Sea. The portion of the Bank in this image illustrates the complex form and topography of the reef system. Several emergent islands (tan) are visible, surrounded primarily by dark green seagrass; the largest is at top left. Only the islands are above the waterline; over the reefs, the water color ranges from light teal (shallow) to turquoise (increasing depth). The southern edge of the reef is well defined by the deep, dark blue water of the Red Sea (top).
In recent years, countries that border the Red Sea have cooperated to form a regional conservation plan for reef ecosystems. The plan includes the designation of several Marine Protected Areas (MPAs), integrated coastal management plans, improved pollution controls, reef health monitoring, and public education efforts. The Al Wadj Bank is one of the areas designated as a MPA.
ISS016-E-19239
The approximately 4-kilometer-wide Dendi Caldera includes some of this silica-rich volcanic rock: the rim of the caldera, visible in this astronaut photograph, is mostly made of poorly consolidated ash erupted during the Tertiary Period (approximately 65–2 million years ago). Two shallow lakes have formed within the central depression (image center). This image also highlights a radial drainage pattern surrounding the remnants of the Dendi volcanic cone. Radial drainage patterns commonly form around volcanoes, as rainfall can flow down slope on all sides of the cone and incise channels. There are no historical records of volcanic eruptions at Dendi, but the Wonchi Caldera, 13 kilometers to the southwest (not shown), may have been active as recently as AD 550.
ISS016-E-10784
The lavas erupted quickly (in about one million years) 31 million years ago, as the tectonic plate carrying Ethiopia passed above what is known as the Afar hotspot, a localized spot of intense heat or magma production that is not at a tectonic plate boundary. As the tectonic plate passed over the hotspot, the general region of Ethiopia rose in elevation. The uplift encouraged the erosion that cut the highly dramatic canyons that ring the plateau.
Although the plateau lies in the latitude of the Sahara-Arabia deserts, its high altitude makes for a cool, wet climate. In fact, the Semien Mountains are one of the few places in Africa to regularly receive snow, and they receive plentiful rainfall (more than 1,280 millimeters, or 55 inches). The moderate climate is shown by light green vegetation on the mountains, compared with the brown canyons, which are hot and dry. The green tinge on the biggest escarpment (trending across the bottom third of the image) is also vegetation, showing that this part of the escarpment also receives more rain than other parts of the escarpment wall. A major canyon cuts the flatter plateau surface (image center), with several more surrounding the plateau. These canyons are hot because they reach low altitudes, more than 2,000 meters below the plateau surface.
The Semien Mountains National Park has been declared a World Heritage Site by the United Nations Educational, Scientific and Cultural Organization for its rugged beauty. In addition, several extremely rare species are found here, such as the Gelada baboon, which has a thick coat to protect against the cold; the critically endangered Walia ibex, which has long, heavy scimitar-like horns; and the Ethiopian wolf, also known as the Semien jackal, which is one of the rarest, and perhaps most endangered canid on Earth.
ISS016-E-34524
Harrat Khaybar contains a wide range of volcanic rock types and spectacular landforms, several of which are represented in this astronaut photograph. Jabal (“mountain” in Arabic) al Qidr is built from several generations of dark, fluid basalt lava flows. Jabal Abyad, in the center of the image, was formed from a more viscous, silica-rich lava classified as a rhyolite. While the 322-meter high Jabal al Qidr exhibits the textbook cone shape of a stratovolcano, Jabal Abyad is a lava dome—a rounded mass of thicker, more solidified lava flows. To the west (image top center) is the impressive Jabal Bayda’. This symmetric structure is a tuff cone, formed by eruption of lava in the presence of water. The combination produces wet, sticky pyroclastic deposits that can build a steep cone structure, particularly if the deposits consolidate quickly.
White deposits visible in the crater of Jabal Bayda’ and two other locations to the south are sand and silt that accumulate in shallow, protected depressions. The tuff cones in the Harrat Khaybar suggest that the local climate was much wetter during some periods of volcanic activity. Today, however, the regional climate is hyperarid—little to no yearly precipitation—leading to an almost total lack of vegetation.
