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  1. 3 points
    Our objective is to provide the scientific and civil communities with a state-of-the-art global digital elevation model (DEM) derived from a combination of Shuttle Radar Topography Mission (SRTM) processing improvements, elevation control, void-filling and merging with data unavailable at the time of the original SRTM production: NASA SRTM DEMs created with processing improvements at full resolution NASA's Ice, Cloud,and land Elevation Satellite (ICESat)/Geoscience Laser Altimeter (GLAS) surface elevation measurements DEM cells derived from stereo optical methods using Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) data from the Terra satellite Global DEM (GDEM) ASTER products developed for NASA and the Ministry of Economy, Trade and Industry of Japan by Sensor Information Laboratory Corp National Elevation Data for US and Mexico produced by the USGS Global Multi-resolution Terrain Elevation Data 2010 (GMTED2010) developed by the USGS and the National Geospatial-Intelligence Agency (NGA) Canadian Digital Elevation Data produced by Natural Resources Canada We propose a significant modernization of the publicly- and freely-available DEM data. Accurate surface elevation information is a critical component in scientific research and commercial and military applications. The current SRTM DEM product is the most intensely downloaded dataset in NASA history. However, the original Memorandum of Understanding (MOU) between NASA and NGA has a number of restrictions and limitations; the original full resolution, one-arcsecond data are currently only available over the US and the error, backscatter and coherence layers were not released to the public. With the recent expiration of the MOU, we propose to reprocess the original SRTM raw radar data using improved algorithms and incorporating ancillary data that were unavailable during the original SRTM processing, and to produce and publicly release a void-free global one-arcsecond (~30m) DEM and error map, with the spacing supported by the full-resolution SRTM data. We will reprocess the entire SRTM dataset from raw sensor measurements with validated improvements to the original processing algorithms. We will incorporate GLAS data to remove artifacts at the optimal step in the SRTM processing chain. We will merge the improved SRTM strip DEMs, refined ASTER and GDEM V2 DEMs, and GLAS data using the SRTM mosaic software to create a seamless, void-filled NASADEM. In addition, we will provide several new data layers not publicly available from the original SRTM processing: interferometric coherence, radar backscatter, radar incidence angle to enable radiometric correction, and a radar backscatter image mosaic to be used as a layer for global classification of land cover and land use. This work leverages an FY12 $1M investment from NASA to make several improvements to the original algorithms. We validated our results with the original SRTM products and ancillary elevation information at a few study sites. Our approach will merge the reprocessed SRTM data with the DEM void-filling strategy developed during NASA's Making Earth System Data Records for Use in Research Environments (MEaSUREs) 2006 project, "The Definitive Merged Global Digital Topographic Data Set" of Co-Investigator Kobrick. NASADEM is a significant improvement over the available three-arcsecond SRTM DEM primarily because it will provide a global DEM and associated products at one-arcsecond spacing. ASTER GDEM is available at one-arcsecond spacing but has true spatial resolution generally inferior to SRTM one-arcsecond data and has much greater noise problems that are particularly severe in tropical (cloudy) areas. At one-arcsecond, NASADEM will be superior to GDEM across almost all SRTM coverage areas, but will integrate GDEM and other data to extend the coverage. Meanwhile, DEMs from the Deutsches Zentrum für Luft- und Raumfahrt Tandem-X mission are being developed as part of a public-private partnership. However, these data must be purchased and are not redistributable. NASADEM will be the finest resolution, global, freely-available DEM products for the foreseeable future. data page: https://lpdaac.usgs.gov/products/nasadem_hgtv001/ news links: https://earthdata.nasa.gov/esds/competitive-programs/measures/nasadem
  2. 2 points
    A new set of 10 ArcGIS Pro lessons empowers GIS practitioners, instructors, and students with essential skills to find, acquire, format, and analyze public domain spatial data to make decisions. Described in this video, this set was created for 3 reasons: (1) to provide a set of analytical lessons that can be immediately used, (2) to update the original 10 lessons created by my colleague Jill Clark and I to provide a practical component to our Esri Press book The GIS Guide to Public Domain Data, and (3) to demonstrate how ArcGIS Desktop (ArcMap) lessons can be converted to Pro and to reflect upon that process. The activities can be found here. This essay is mirrored on the Esri GeoNet education blog and the reflections are below and in this video. Summary of Lessons: Can be used in full, in part, or modified to suit your own needs. 10 lessons. 64 work packages. A “work package” is a set of tasks focused on solving a specific problem. 370 guided steps. 29 to 42 hours of hands-on immersion. Over 600 pages of content. 100 skills are fostered, covering GIS tools and methods, working with data, and communication. 40 data sources are used, covering 85 different data layers. Themes covered: climate, business, population, fire, floods, hurricanes, land use, sustainability, ecotourism, invasive species, oil spills, volcanoes, earthquakes, agriculture. Areas covered: The Globe, and also: Brazil, New Zealand, the Great Lakes of the USA, Canada, the Gulf of Mexico, Iceland, the Caribbean Sea, Kenya, Orange County California, Nebraska, Colorado, and Texas USA. Aimed at university-level graduate and university or community college undergraduate student. Some GIS experience is very helpful, though not absolutely required. Still, my advice is not to use these lessons for students’ first exposure to GIS, but rather, in an intermediate or advanced setting. How to access the lessons: The ideal way to work through the lessons is in a Learn Path which bundle the readings of the book’s chapters, selected blog essays, and the hands-on activities.. The Learn Path is split into 3 parts, as follows: Solving Problems with GIS and public domain geospatial data 1 of 3: Learn how to find, evaluate, and analyze data to solve location-based problems through this set of 10 chapters and short essay readings, and 10 hands-on lessons: https://learn.arcgis.com/en/paths/the-gis-guide-to-public-domain-data-learn-path/ Solving Problems with GIS and public domain geospatial data 2 of 3: https://learn.arcgis.com/en/paths/the-gis-guide-to-public-domain-data-learn-path-2/ Solving Problems with GIS and public domain geospatial data 3 of 3: https://learn.arcgis.com/en/paths/the-gis-guide-to-public-domain-data-learn-path-3/ The Learn Paths allow for content to be worked through in sequence, as shown below: You can also access the lessons by accessing this gallery in ArcGIS Online, shown below. If you would like to modify the lessons for your own use, feel free! This is why the lessons have been provided in a zipped bundle as PDF files here and as MS Word DOCX files here. This video provides an overview. source: https://spatialreserves.wordpress.com/2020/05/14/10-new-arcgis-pro-lesson-activities-learn-paths-and-migration-reflections/
  3. 2 points
    Stop me if you’ve heard this before. DJI has introduced its latest enterprise powerhouse drone, the DJI Matrice 300 RTK. We learned a lot about the drone earlier this week due to a few huge leaks of specs, features, photos, and videos. But it’s worth looking at the drone again now that it’s official – and an incredible intro video. Also called the M300 RTK, this drone is an upgrade in every way over its predecessor, the M200 V2. That includes a very long flight time of 55 minutes, six-direction obstacle avoidance, and a doubled (6 pound) payload capability. That allows it to carry a range of powerful cameras, which we’ll get to in a bit. The drone is also built for weather extremes. IP45 weather sealing keeps out rain and dust. And a self-heating battery helps the drone to run in a broad range of temperatures, from -4 to 122 Fahrenheit. The DJI Matrice 300 RTK can fly up to 15 kilometers (9.3 miles) from its controller and still stream 1080p video back home. That video and other data can be protected using AES-256 encryption. The drone can also be flown by two co-pilots, with one able to take over for the other if any problem arises or a handoff scenario. A workhorse inspection drone All these capabilities are targeted to the DJI Matrice 300 RTK’s purpose as a drone for heavy-duty visual inspection and data collection work, such as surveys of power lines or railways. In fact, it incorporates many advanced camera features for the purpose. Smart inspection is a new set of features to optimize data collection. It includes live mission recording, which allows the drone to record every aspect of a flight, even camera settings. This allows workers to train a drone on an inspection mission that it will repeat again and again. With AI spot check, operators can mark the specific part of the photo, such as a transformer, that is the subject of inspection. AI algorithms compare that to what the camera sees on a future flight, so that it can frame the subject identically on every flight. An inspection drone is only as good as its cameras, and the M300 RTK offers some powerful options from DJI’s Zenmuse H20 series. The first option is a triple-camera setup. It includes a 20-megapixel, 23x zoom camera; a 12MP wide-angle camera; and a laser rangefinder that measures out to 1,200 meters (3,937 feet). The second option adds a radiometric thermal camera. TO make things simpler for operators, the drone provides a one-click capture feature that grabs videos or photos from three cameras at once, without requiring the operator to switch back and forth. Eyes and ears ready for danger With its flight time and range, the DJI Matrice 300 RTK could be flying some long, complex missions, easily beyond visual line of site (if its owner gets an FAA Part 107 waiver for that). This requires some solid safety measures. While the M200 V2 has front-mounted sensors, the M300 RTK has sensors in six directions for full view of the surroundings. The sensors can register obstacles up to 40 meters (98 feet) away. Like all new DJI drones, the M300 RTK also features the company’s AirSense technology. An ADS-B receiver picks up signals from manned aircraft that are nearby and alerts the drone pilot of their location. It’s been quite a few weeks for DJI. On April 27, it debuted its most compelling consumer drone yet, the Mavic Air 2. Now it’s showing off its latest achievement at the other end of the drone spectrum with the industrial grade Matrice 300 RTK. These two, very different drones help illustrate the depth of product that comes from the world’s biggest drone maker. And the company doesn’t show signs of slowing down, despite the COVID-19 economic crisis. Next up, we suspect, will be a revision to its semi-pro quadcopter line in the firm of a Mavic 3. It is available at DJI.It’s been quite a few weeks for DJI. On April 27, it debuted its most compelling consumer drone yet, the Mavic Air 2. Now it’s showing off its latest achievement at the other end of the drone spectrum with the industrial grade Matrice 300 RTK. These two, very different drones help illustrate the depth of product that comes from the world’s biggest drone maker. And the company doesn’t show signs of slowing down, despite the COVID-19 economic crisis. Next up, we suspect, will be a revision to its semi-pro quadcopter line in the firm of a Mavic 3. It is available at DJI. source: https://dronedj.com/2020/05/07/dji-matrice-300-rtk-drone-official/
  4. 2 points
    @intertronic, thanks for your input. I found a solution that suite my case better due to the fact that we are using both version of QGIS and also because I was looking for interoperability. Therefore I have decided to use QSphere. Most probably not well known around the globe. https://qgis.projets.developpement-durable.gouv.fr/projects/qsphere GUI quiete ugly but at least is doing the job. 😉 darksabersan
  5. 2 points
    DRONE MAKER DJI announced an update to its popular Mavic Air quadcopter today. The Mavic Air 2 will cost $799 when it ships to US buyers in late May. That's the same price as the previous Mavic Air model, so the drone stays as DJI's mid-range option between its more capable Mavic 2 and its smaller, cheaper Mavic Mini. The Mavic Air 2 is still plenty small, but the new version has put on some weight. DJI says that testing and consumer surveys suggested that most people don't mind lugging a few extra grams in exchange for a considerable upgrade in flight time and, presumably, better handling in windy conditions. Even better, thanks to a new rotor design and other aerodynamic improvements, DJI is claiming the Mavic Air 2 can remain aloft for 34 minutes—a big jump from the 21 minutes of flight time on the original Mavic Air. The Camera Eye he big news in this update is the new larger imaging sensor on the drone's camera. The Mavic Air 2's camera ships with a half-inch sensor, up from the 1 2/3-inch sensor found in the previous model. That should mean better resolution and sharper images, especially because the output specs haven't changed much. The new camera is still outputting 12-megapixel stills, but now has a bigger sensor to fill that frame with more detail. There's also a new composite image option that joins together multiple single shots into a large, 48-megapixel image. On the video side, there's some exciting news. The Mavic Air 2 is DJI's first drone to offer 4K video at 60 frames per second and 120 Mbps—previous DJI drones topped out at 30 fps when shooting in full 4K resolution. There are also slow-motion modes that slow down footage to four times slower than real life (1080p at 120 fps), or eight-times slower (1080 at 240 fps). Combine those modes with the more realistic contrast you get with the HDR video standard, and you have considerably improved video capabilities in a sub-$1,000 drone. More interesting in some ways is DJI's increasing forays into computational photography, which the company calls Smart Photo mode. Flip on Smart Photo and the Mavic Air 2 will do scene analysis, tap its machine intelligence algorithm and automatically choose between a variety of photo modes. There's a scene recognition mode where the Mavic Air 2 sets the camera up to best capture one of a variety of scenarios you're likely to encounter with drone photography, including blue skies, sunsets, snow, grass, and trees. In each case, exposure is adjusted to optimize tone and detail. The second Smart Photo mode is dubbed Hyperlight, which handles low-light situations. To judge by DJI's promo materials, this is essentially an HDR photography mode specifically optimized for low-light scenes. It purportedly cuts noise and produces more detailed images. The final smart mode is HDR, which takes seven images in rapid succession, the combines elements of each to make a final image with a higher dynamic range. One last note about the camera: The shape of the camera has changed, so if you have any lenses or other accessories for previous DJI drones, they won't attach to the Air 2. Automatic Flight for the People If you dig through older YouTube videos there's a ton of movies that play out like this: unbox new drone, head outside, take off, tree gets closer, closer, closer, black screen. Most of us just aren't that good at flying, and the learning curve can be expensive and steep. Thankfully drone companies began automating away most of what's difficult about piloting a quadcopter, and DJI is no exception. The company has added some new automated flight tricks to the Air's arsenal. DJI's Active Track has been updated to version 3.0, which brings better subject recognition algorithms and some new 3D mapping tricks to make it easier to automatically track people through a scene, keeping the camera on the subject as the drone navigates overhead to stay with them. DJI claims the Point of Interest mode—which allows you to select an object and fly around it in a big circle while the camera stays pointed at the subject—is better at tracking some of the objects that previous versions struggled with, like vehicles or even people. The most exciting new flight mode is Spotlight, which comes from DJI's high-end Inspire drone used by professional photographers and videographers to carry their DSLR cameras into the sky. Similar to the Active Track mode, Spotlight keeps the camera pointed a moving subject. But while Active Track automates the drone's flight, the new Spotlight mode allows the human pilot to retain control of the flight path for more complex shots. Finally, the range of the new Mavic Air 2 has been improved, and it can now wander an impressive six miles away from the pilot in ideal conditions. The caveat here is that you should always maintain visual contact with your drone for safety reasons. However, you aren't going to be able to see the Mavic Air 2 when it's two miles away, let alone six. Despite a dearth of competitors, DJI continues to put out new drones and improve its lineup as it progresses. The Mavic Air 2 looks like an impressive update to what was already one of our favorite drones, especially considering several features—the 60 fps 4K video and 34 minute flight time—even best those found on the more expensive Mavic 2 Pro. links: https://www.dji.com/id/mavic-air-2
  6. 2 points
    I like drones but just got more interested in this,
  7. 2 points
    Interesting application of WebGIS to plot Dinosaur database, and you can search how is your place in the past on the interactive globe Map. Welcome to the internet's largest dinosaur database. Check out a random dinosaur, search for one below, or look at our interactive globe of ancient Earth! Whether you are a kid, student, or teacher, you'll find a rich set of dinosaur names, pictures, and facts here. This site is built with PaleoDB, a scientific database assembled by hundreds of paleontologists over the past two decades. check this interactive webgis apps: https://dinosaurpictures.org/ancient-earth#170 official link: https://dinosaurpictures.org/
  8. 1 point
    for those like me who are not English mother tongue I recommend this site for translations (English - French - German - Italian - Spanish - Portuguese - Russian - Chinese - Japanese etc.)... fantastic and intuitive that is based on artificial intelligence https://www.deepl.com/ another interesting website https://www.linguee.com/
  9. 1 point
    GRASS GIS was, for a long time, something I dismissed as ‘too complex’ for my everyday geospatial operations. I formulated any number of excuses to work around the software and could not be convinced it had practical use in my daily work. It was ‘too hard to set-up’, ‘never worked well with QGIS’, and ‘made my scripting processes a nightmare’. In this example we will: part 1: 1. Download a small piece of elevation data from the LINZ Data Service 2. Build a GRASS environment to process these data 3. Build a BASH script to process the catchments 4. Import the elevation into the GRASS environment 5. Perform some basic GRASS operations (fill and watershed) 6. Export raster format for viewing 7. Export the vector catchments to shapefile part 2: 1. Creating multiple watershed boundaries of different sizes with GRASS and using a basic loop in BASH for the process. 2. Clipping the original raster by the watershed boundaries using GDAL and SQL with a basic loop in BASH. links: part 1: https://xycarto.com/2020/05/03/basic-grass-gis-with-bash/ part 2: https://xycarto.com/2020/05/05/basic-grass-gis-with-bash-plus-gdal/ source code: https://github.com/xycarto/xycarto_code/tree/master/scripts/grass/GRASS_BASH_blog
  10. 1 point
    Changes in ocean circulation may have caused a shift in Atlantic Ocean ecosystems not seen for the past 10,000 years, new analysis of deep-sea fossils has revealed. This is the striking finding of a new study led by a research group I am part of at UCL, funded by the ATLAS project and published in the journal Geophysical Research Letters. The shift has likely already led to political tensions as fish migrate to colder waters. The climate has been quite stable over the 12,000 years or so since the end of the last Ice Age, a period known as the Holocene. It is thought that this stability is what allowed human civilisation to really get going. In the ocean, the major currents are also thought to have been relatively stable during the Holocene. These currents have natural cycles, which affect where marine organisms can be found, including plankton, fish, seabirds and whales. Yet climate change in the ocean is becoming apparent. Tropical coral reefs are bleaching, the oceans becoming more acidic as they absorb carbon from the atmosphere, and species like herring or mackerel are moving towards the poles. But there still seems to be a prevailing view that not much has happened in the ocean so far – in our minds the really big impacts are confined to the future. Looking into the past To challenge this point of view, we had to look for places where seabed fossils not only covered the industrial era in detail, but also stretched back many thousands of years. And we found the right patch of seabed just south of Iceland, where a major deep sea current causes sediment to pile up in huge quantities. To get our fossil samples we took cores of the sediment, which involves sending long plastic tubes to the bottom of the ocean and pushing them into the mud. When pulled out again, we were left with a tube full of sediment that can be washed and sieved to find fossils. The deepest sediment contains the oldest fossils, while the surface sediment contains fossils that were deposited within the past few years. One of the simplest ways of working out what the ocean was like in the past is to count the different species of tiny fossil plankton that can be found in such sediments. Different species like to live in different conditions. We looked at a type called foraminifera, which have shells of calcium carbonate. Identifying them is easy to do using a microscope and small paintbrush, which we use when handling the fossils so they don't get crushed. A recent global study showed that modern foraminifera distributions are different to the start of the industrial era. Climate change is clearly already having an impact. Similarly, the view that modern ocean currents are like those of the past couple of thousand years was challenged by our work in 2018, which showed that the overturning "conveyor belt" circulation was at its weakest for 1,500 years. Our new work builds on this picture and suggests that modern North Atlantic surface circulation is different to anything seen in the past 10,000 years – almost the whole Holocene. The effects of the unusual circulation can be found across the North Atlantic. Just south of Iceland, a reduction in the numbers of cold-water plankton species and an increase in the numbers of warm-water species shows that warm waters have replaced cold, nutrient-rich waters. We believe that these changes have also led to a northward movement of key fish species such as mackerel, which is already causing political headaches as different nations vie for fishing rights. Further north, other fossil evidence shows that more warm water has been reaching the Arctic from the Atlantic, likely contributing to melting sea ice. Further west, a slowdown in the Atlantic conveyor circulation means that waters are not warming as much as we would expect, while furthest west close to the US and Canada the warm gulf stream seems to be shifting northwards which will have profound consequences for important fisheries. One of the ways that these circulation systems can be affected is when the North Atlantic gets less salty. Climate change can cause this to happen by increasing rainfall, increasing ice melt, and increasing the amount of water coming out of the Arctic Ocean. Melting following the peak of the Little Ice Age in the mid 1700s may have triggered an input of freshwater, causing some of the earliest changes that we found, with modern climate change helping to propel those changes beyond the natural variability of the Holocene. We still don't know what has ultimately caused these changes in ocean circulation. But it does seem that the ocean is more sensitive to modern climate changes than previously thought, and we will have to adapt. source: https://www.sciencealert.com/fossils-reveal-our-ocean-is-changing-in-a-ways-it-hasn-t-for-10-000-years
  11. 1 point
    6x open positions (as of 24.04.2020) French site (simple put "GIS" or "Swisstopo" in the search area) https://www.stelle.admin.ch/stelle/fr/home/stellen/stellenangebot.html German https://www.stelle.admin.ch/stelle/de/home/stellen/stellenangebot.html
  12. 1 point
    or another swiss/french site : https://www.camptocamp.com/en/jobs/
  13. 1 point


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