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CADGIS
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Map, CAD, GIS, Science informations
Map, CAD, GIS, Science informations

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Google 街景無極限,前進國際太空站! - INSIDE 硬塞的網路趨勢觀察
https://www.inside.com.tw/2017/07/21/google-street-view-lands-on-the-international-space-station/amp

Googleストリートビューがついに宇宙に進出、自宅から国際宇宙ステーション(ISS)を探索可能に - GIGAZINE
http://gigazine.net/amp/20170721-google-streetview-iss

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Historical Maps at Your Fingertips: TopoView can now be accessed through various portable devices like smartphones and tablets.(Public domain.) TopoView 2.1 is a modern web application built on an open source mapping platform that is free of charge. The highly interactive service provides tools and procedures that allow users to easily find historic map scans from USGS’s Historical Topographic Map Collection and even compare those with modern day maps. The new version is full of improvements and advancements based on hundreds of user comments and suggestions. Upgraded features include: new user interface that’s faster and  easier to use, access and download maps from a variety of search terms intuitive tools to compare historical maps with maps of the present. ability to preview maps within the interface filters and searches that work seamlessly with the map records table to get you the info you want with just a few clicks. To further assist users with these features, the TopoView team has released a “how to” video to walk through the download and comparison process. TopoView highlights one of the USGS's most important and useful products, the topographic map. In 1879, the USGS began to map the Nation's topography. This mapping was done at different levels of detail, in order to support various land use and other purposes. As the years passed, the USGS produced new map versions of each area. The most current maps are available from The National Map and US Topo quadrangles. TopoView shows the many and varied older maps of each area, and so is useful for historical purposes—for example, the names of some natural and cultural features have changed over time, and the 'old' names can be found on these historical topographic maps.  TopoView was created by the National Geologic Map Database project, in support of topographic mapping program managed by the National Geospatial Program.  Geologic mapping and topographic mapping at the USGS have a long tradition together. ​Comparing modern-day Philadelphia to the historical map of the area in 1891. TopoView lets users easily visualize changes to areas that were mapped by the USGS throughout history.(Public domain.)     #usgs #news

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New App Shows Aquifer Level Change and Subsidence in Relation to Groundwater Withdrawals in Houston-Galveston Area: Regional groundwater-level altitude contours and groundwater-level altitude at wells for the Chicot aquifer; and cumulative compaction data, Houston-Galveston region, Texas, 2016.A new interactive web application illustrates how groundwater, sediment compaction and land-elevation change are related in the Houston-Galveston region in Texas. (Public domain.) The Houston-Galveston region represents one of the largest areas of land-surface elevation change, or subsidence, in the United States. Most of the land subsidence in this region has occurred as a direct result of groundwater withdrawals for municipal supply, commercial and industrial use and irrigation. This new tool can help resource managers make informed decisions on water usage. “The water-level and compaction data provided by the USGS is absolutely critical for water managers and planners to make informed resource management decisions throughout the region,” said Mike Turco, general manager of the Harris Galveston and Fort Bend Subsidence Districts. “This information is used by the District to provide a better understanding of the impact of our regulatory plan on aquifer water levels and subsidence.” The new USGS viewer shows how water levels have changed over time and how groundwater demands have affected land subsidence in the region. Scientists created this tool using the largest subsidence data set in the US with more than 40 years of groundwater and compaction observations. This long-term data was essential to the project, and was collected in cooperation with the Harris-Galveston Subsidence District, City of Houston, Fort Bend Subsidence District, the Lone Star Groundwater Conservation District and the Brazoria County Groundwater Conservation District. “This is the first time that groundwater and subsidence data have been put together to illustrate the story of what is happening to our land and water resources in the region,” said Sachin Shah, USGS chief of Gulf Coast hydrologic studies and research. “The ability to explore, visualize and compare how groundwater levels are changing over time in an easily accessible and uniform format is a tool that we hope will effectively communicate this information to area cooperators, stakeholders, and the public.” To access previous publications on subsidence in the Houston-Galveston region, visit the USGS Texas Gulf Coast Groundwater and Land Subsidence website. Split screen view of regional groundwater-level altitude contours for the Chicot aquifer, 2016 and 1977, Houston-Galveston region, Texas. (Public domain.) USGS hydrologist Jason Ramage collects a groundwater-level measurement using a steel tape in Freeport, Texas. (Credit: Sachin Shah, USGS . Public domain.) #usgs #news

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"Our Advise is... Bring your car to Cuba as part of your personal baggage." A perspective we hadn't seen before from c. 1950 that hints at the freedom and exhilaration of exploring the island that you can find by taking your own car to Cuba. Drive the "Magnificent Central Highway" #oldmapgallery #CUBA! #oldmaps #cubanos 
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When people think of "old maps" this might be close to what they first imagine, an old chart that is weathered and has some "character". Showing the "Atlantic or Western Ocean" and the "Florida Stream" that can speed you to Europe its a good early 19th century view of the passage between the continents. #oldmapgallery #antiquemaps #oldmaps #HAPPYFRIDAY! 
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Ice on the Move in Patagonia

“The glaciers of Patagonia are some of the most temperate, fastest, and most erosive glaciers on Earth,” notes Michele Koppes, a glaciologist from the University of British Columbia. “The moist, warm climate drives very fast flow and allows the glaciers to do a lot of work on the landscape, carving deep fjords in one one-hundredth the time it takes similar glaciers in the polar regions to create the same landscapes.”

Scientists have long wondered: how fast is Patagonia’s ice changing? Over the years, they have mapped the velocities of a few of the outlet glaciers. (These ring the perimeter and drain the icefields.) Then in 2015, Jeremie Mouginot of University of California, Irvine, and Eric Rignot of NASA’s Jet Propulsion Laboratory published the first thorough, high-resolution mosaic of ice speed across the icefields.

The results of their work are shown in the map above. The ice velocities were derived from radar interferometry observations collected from multiple satellites between 1984 and 2014. Interferometry is a technique that uses precise measurements of changes in distance between the satellite and points on the ground to calculate the speed of relatively slow-moving features on Earth. Because the map is a mosaic of data that spans two decades, it can be interpreted as a general representation of conditions at the median year (2004). Large local changes, however, can occur between season and years.

“The only way we could map entirely the ice speed of the ice fields was to put together acquisitions from six different space satellites operated during the last 30 years,” Mouginot said. “The result actually revealed a very different picture of ice velocities. By completely redefining the glacier extents into the ice fields, we showed that the glaciers may have a more significant and widespread influence on the mass balance of the region than previously thought.”

Ice is moving at a huge range of speeds across Patagonia, from as little as a few centimeters to as much as 10,000 meters per year. In this map, yellow areas are moving the fastest and purple areas are the slowest. Notice the significant amount of green; almost half of the ice is moving at speeds faster than 100 meters per year.

“The difference in the waters—warm and salty in the west, and colder and fresher in the east—also controls the calving and internal dynamics of the outlet glaciers,” Koppes said. She notes that melting at the ice fronts due to ocean heat can draw down western glaciers at 5 to 10 times the rate of glaciers in the east.

San Rafael is the fastest moving glacier on the north icefield. It was flowing at about 7.6 kilometers per year in 1994, and has since decelerated. Perhaps the most notable glacier of the south icefield is Jorge Montt. Data show that the speed of this glacier more than doubled between 1986 and 2000. It then slowed down by 30 percent between 2000 and 2008, and accelerated again by 115 percent between 2008 and 2014.

“The spectacular retreat of Jorge Montt in the 1990s is explained by the bathymetry: the glacier retreated along a reverse bed during these years; that is, a bed that is getting deeper inland,” Rignot said. “This is an unstable configuration for the glacier, causing it to retreat rapidly until it reaches higher ground.”

The acceleration and retreat of Patagonia’s glaciers can have a multitude of effects on the landscape. The glaciers produce mounds of sediment that clog the rivers, fjords, and waterways; this alters aquatic habitats and reroutes water resources, according to Koppes. And along the western margin of the South Patagonian Icefield, ships that pass through the fjords must contend with the numerous icebergs that calve from the glacier fronts.

Koppes added: “Given ongoing climate change, the glaciers of the north and south Patagonia icefields are important predictors of what we expect to occur in the coming decades in other glaciated, high-latitude regions, such as the Antarctic Peninsula and the Canadian Arctic, which are experiencing some of the most rapid warming on the planet.”

https://go.nasa.gov/2tTYnZq
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Landsat 8 Looks at Iceberg A-68

Early on July 12, 2017, satellites captured imagery of the new, massive iceberg that broke away from Larsen C—an ice shelf on the east side of the Antarctic Peninsula. Later that day, the Landsat 8 satellite acquired a more detailed look.

The false-color image was captured by Landsat’s Thermal Infrared Sensor (TIRS). It shows the relative warmth or coolness of the landscape. Orange indicates where the surface is the warmest, most notably the mélange between the new berg and the ice shelf. Light blues and whites are the coldest areas, including the ice shelf and the iceberg.

On July 13, the U.S. National Ice Center issued a press release confirming the new iceberg and officially naming it A-68.

Read the full post:
https://earthobservatory.nasa.gov/NaturalHazards/view.php?id=90574

See more satellite imagery of iceberg A-68:
https://earthobservatory.nasa.gov/NaturalHazards/view.php?id=90557
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7/13/17
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Island Rises Up off of Cape Hatteras

The waters off of North Carolina’s barrier islands have been called a “graveyard of the Atlantic.” Countless ships have wrecked here, due to the area’s treacherous weather and currents and its expansive shoals. These shoals are, by definition, usually submerged. But occasionally parts of them can rise above sea level.

These natural-color images, acquired by the Operational Land Imager (OLI) on the Landsat 8 satellite, show the shoal area off of Cape Point at Cape Hatteras National Seashore—the site of a newly exposed shoal nicknamed “Shelly Island.” The first image was captured in November 2016. When the second image was acquired in January 2017, waves were clearly breaking on the shallow region off the cape’s tip. The site of those breakers is where the island eventually formed, visible in the third image captured in July 2017. The new island measures about a mile long, according to news reports.

“What exactly causes a shallow region to become exposed is a deep question, and one that is difficult to speculate on without exact observations,” said Andrew Ashton, a geomorphologist at the Woods Hole Oceanographic Institution. “A likely process would be a high tide or storm-driven water elevation that piled up sediment to near the surface, and then water levels went down exposing the shoal. Waves then continue to build the feature while also moving it about.”

While the exact mechanism for the formation of Shelly Island this year is mostly unknown, the phenomenon is not uncommon. Cape Lookout, the next cape down the barrier islands (to the southwest, beyond this image) has had several islands form on its shoal over the past decade or two.

The shoreline and cape tips along North Carolina’s barrier islands are constantly in motion. Cape tips are sculpted by waves and currents that hit from all directions. Meanwhile, sediment is carried up and down the coastline and often deposited near the cape tips. Each cape has a so-called “cape-associated shoal” lurking underwater. These submerged mounds of sand can extend for tens of kilometers. They are also very shallow, rising to anywhere from 10 meters to a few meters below the surface in places.

“Tidal flows moving up and down the coast are diverted by the capes and result in a net offshore current at cape tips and deposition at the shoals,” Ashton said. “Occasionally, a portion of the shoal becomes exposed and forms an island.”

https://go.nasa.gov/2ueoFYh
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Mapping Climate Science

This interactive map from Carbon Brief plots scientific studies of extreme climate events to determine if they have been caused by human activity or not.

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